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Balance Confidence Was Associated With Mobility and Balance Performance in Older People With Fall-Related Hip Fracture: A Cross-Sectional Study

      Abstract

      Portegijs E, Edgren J, Salpakoski A, Kallinen M, Rantanen T, Alen M, Kiviranta I, Sihvonen S, Sipilä S. Balance confidence was associated with mobility and balance performance in older people with fall-related hip fracture: a cross-sectional study.

      Objective

      To study the relationship between balance confidence, a concept closely related to fear of falling, mobility and balance performance, and perceived mobility limitation in older people after a fall-related hip fracture.

      Design

      Cross-sectional analyses of pretrial data of 2 randomized controlled trials of physical rehabilitation.

      Setting

      University research center.

      Participants

      Community-dwelling people aged over 60 years, 6 weeks to 7.5 years after a fall-related hip fracture (N=130).

      Interventions

      Not applicable.

      Main Outcome Measures

      The main outcome was the self-reported Activities-specific Balance Confidence (ABC) scale score. Assessments also included perceived ability to walk outdoors or climb 1 flight of stairs, and assessments of self-preferred walking speed, modified Timed-Up-and-Go test, and Berg Balance Scale.

      Results

      Higher ABC scale scores were related to better mobility and balance performance (ρ>.47) and perceived mobility function (ρ>.54). In univariate general linear models, all associations also remained significant after adjustment for age, sex, time since fracture, number of chronic diseases, and either level of physical activity or muscle strength of the fractured leg. An ABC scale score <85 points identified those with mobility and balance limitation across measures.

      Conclusions

      In people who have had a fall-related hip fracture, an independent relationship exists between balance confidence and mobility and balance performance as well as perceived mobility function. Since lack of balance confidence may compromise rehabilitation and recovery, the ABC scale may help to identify older hip fracture patients with mobility and balance limitation.

      Key Words

      List of Abbreviations:

      ABC (Activities-specific Balance Confidence), BBS (Berg Balance Scale), TUG (Timed-Up-and-Go)
      FEAR OF FALLS and lack of balance confidence, 2 closely related concepts,
      • Bandura A.
      Self-efficacy: toward a unifying theory of behavioral change.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      may exist among older people with or without a history of falls. However, those with experience of a fall or fall-related trauma are likely to adapt their behavior because of fear of a new fall. After hip fracture, older people often experience lack of balance confidence, which may be a correct appraisal of their increased risk for falls.
      • Hadjistavropoulos T.
      • Delbaere K.
      • Fitzgerald T.D.
      Reconceptualizing the role of fear of falling and balance confidence in fall risk.
      Older people who have suffered a hip fracture have a markedly increased risk for future falls and new fractures in comparison with healthy older people.
      • Lloyd B.D.
      • Williamson D.A.
      • Singh N.A.
      • et al.
      Recurrent and injurious falls in the year following hip fracture: a prospective study of incidence and risk factors from the sarcopenia and hip fracture study.
      Partly, this increased risk is due to impairments in lower-limb muscle strength, mobility, and balance performance that persist even years after the fracture.
      • Lloyd B.D.
      • Williamson D.A.
      • Singh N.A.
      • et al.
      Recurrent and injurious falls in the year following hip fracture: a prospective study of incidence and risk factors from the sarcopenia and hip fracture study.
      • Madsen O.R.
      • Lauridsen U.B.
      • Sorensen O.H.
      Quadriceps strength in women with a previous hip fracture: relationships to physical ability and bone mass.
      • Portegijs E.
      • Kallinen M.
      • Rantanen T.
      • et al.
      Effects of resistance training on lower-extremity impairments in older people with hip fracture.
      • Sihvonen S.
      • Kulmala J.
      • Kallinen M.
      • Alen M.
      • Kiviranta I.
      • Sipila S.
      Postural balance and self-reported balance confidence in older adults with a hip fracture history.
      • Visser M.
      • Harris T.B.
      • Fox K.M.
      • et al.
      Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery.
      • Sherrington C.
      • Lord S.R.
      Increased prevalence of fall risk factors in older people following hip fracture.
      Recovery to prefracture levels of functioning occurs in about one third of persons surviving hip fracture.
      • Lloyd B.D.
      • Williamson D.A.
      • Singh N.A.
      • et al.
      Recurrent and injurious falls in the year following hip fracture: a prospective study of incidence and risk factors from the sarcopenia and hip fracture study.
      • Visser M.
      • Harris T.B.
      • Fox K.M.
      • et al.
      Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery.
      • Marottoli R.A.
      • Berkman L.F.
      • Cooney Jr, L.M.
      Decline in physical function following hip fracture.
      Balance confidence may contribute to the lack of functional recovery after hip fracture. Lack of balance confidence and fear of falling are reported to have a debilitating effect on mobility and functioning in geriatric rehabilitation patients
      • Denkinger M.D.
      • Igl W.
      • Lukas A.
      • et al.
      Relationship between fear of falling and outcomes of an inpatient geriatric rehabilitation population—fear of the fear of falling.
      and residents
      • Myers A.M.
      • Fletcher P.C.
      • Myers A.H.
      • Sherk W.
      Discriminative and evaluative properties of the Activities-specific Balance Confidence (ABC) scale.
      and accelerate the decline in mobility function in relatively healthy older people.
      • Deshpande N.
      • Metter E.J.
      • Lauretani F.
      • Bandinelli S.
      • Guralnik J.
      • Ferrucci L.
      Activity restriction induced by fear of falling and objective and subjective measures of physical function: a prospective cohort study.
      • Cumming R.G.
      • Salkeld G.
      • Thomas M.
      • Szonyi G.
      Prospective study of the impact of fear of falling on activities of daily living, SF-36 scores, and nursing home admission.
      Lack of balance confidence may cause a vicious circle of further deterioration of function through avoidance of activities in which a person observes an increased fall risk.
      • Hadjistavropoulos T.
      • Delbaere K.
      • Fitzgerald T.D.
      Reconceptualizing the role of fear of falling and balance confidence in fall risk.
      Avoidance of physical activities causes the muscle strength to decrease, which further increases the risk for mobility and balance limitation and even disability.
      • Visser M.
      • Harris T.B.
      • Fox K.M.
      • et al.
      Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery.
      • Rantanen T.
      • Avlund K.
      • Suominen H.
      • Schroll M.
      • Frandin K.
      • Pertti E.
      Muscle strength as a predictor of onset of ADL dependence in people aged 75 years.
      On the other hand, engaging in physical activities through ordinary daily activities or physical rehabilitation has a training effect in more frail older people.
      • Sylliaas H.
      • Brovold T.
      • Wyller T.B.
      • Bergland A.
      Progressive strength training in older patients after hip fracture: a randomised controlled trial.
      • Binder E.F.
      • Brown M.
      • Sinacore D.R.
      • Steger-May K.
      • Yarasheski K.E.
      • Schechtman K.B.
      Effects of extended outpatient rehabilitation after hip fracture: a randomized controlled trial.
      Balance confidence is task-specific. The Activities-specific Balance Confidence (ABC) scale assesses a person's confidence to perform different tasks without losing balance or falling.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      Assessing the ABC scale takes only a few minutes and may thus be feasible in clinical practice as well.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      The ABC scale is related to different mobility and balance performance measures in relatively healthy samples of older people.
      • Talley K.M.
      • Wyman J.F.
      • Gross C.R.
      Psychometric properties of the Activities-specific Balance Confidence scale and the survey of activities and fear of falling in older women.
      • Schepens S.
      • Goldberg A.
      • Wallace M.
      The short version of the Activities-specific Balance Confidence (ABC) scale: its validity, reliability, and relationship to balance impairment and falls in older adults.
      • Reelick M.F.
      • van Iersel M.B.
      • Kessels R.P.
      • Rikkert M.G.
      The influence of fear of falling on gait and balance in older people.
      Its use in more frail older populations, such as hip fracture patients, has been questioned because of its large range of activities.
      • Visschedijk J.
      • Achterberg W.
      • Van Balen R.
      • Hertogh C.
      Fear of falling after hip fracture: a systematic review of measurement instruments, prevalence, interventions, and related factors.
      In hip fracture patients, other measures of fear of falling and balance confidence have been associated with both mobility performance and perceived mobility function.
      • Visschedijk J.
      • Achterberg W.
      • Van Balen R.
      • Hertogh C.
      Fear of falling after hip fracture: a systematic review of measurement instruments, prevalence, interventions, and related factors.
      A previous study of our group suggested that the ABC scale was feasible in people with a history of hip fracture.
      • Sihvonen S.
      • Kulmala J.
      • Kallinen M.
      • Alen M.
      • Kiviranta I.
      • Sipila S.
      Postural balance and self-reported balance confidence in older adults with a hip fracture history.
      The relationship between the ABC scale and functional balance was stronger among those with a history of hip fracture than among age- and sex-matched healthy controls.
      • Sihvonen S.
      • Kulmala J.
      • Kallinen M.
      • Alen M.
      • Kiviranta I.
      • Sipila S.
      Postural balance and self-reported balance confidence in older adults with a hip fracture history.
      Our aim was to examine the relationship between performance-based and self-reported measures of mobility and balance function in older people with a previous fall-related hip fracture. In addition, the study aimed to determine whether this relationship remained after adjustment, including potential underlying mechanisms, such as reduced physical activity level and poor muscle strength. Finally, we searched for a cutoff value for the ABC scale to identify those with mobility and balance limitation across the different measures.

      Methods

      Study Design

      This study was a joint analysis of 2 randomized controlled trials investigating health, functional capacity, and rehabilitation of people with a history of hip fracture.
      • Portegijs E.
      • Rantanen T.
      • Kallinen M.
      • et al.
      Lower-limb pain, disease, and injury burden as determinants of muscle strength deficit after hip fracture.
      • Sipila S.
      • Salpakoski A.
      • Edgren J.
      • et al.
      Promoting mobility after hip fracture (ProMo): study protocol and selected baseline results of a year-long randomized controlled trial among community-dwelling older people.
      Both studies were performed at the same research center, using the same equipment, and participants were recruited from the same health care district with identical inclusion and exclusion criteria. Data of these studies were pooled to increase sample size. Only the pretrial data are used in this cross-sectional study.

      Participants

      The methods of both trials have been described before.
      • Portegijs E.
      • Rantanen T.
      • Kallinen M.
      • et al.
      Lower-limb pain, disease, and injury burden as determinants of muscle strength deficit after hip fracture.
      • Sipila S.
      • Salpakoski A.
      • Edgren J.
      • et al.
      Promoting mobility after hip fracture (ProMo): study protocol and selected baseline results of a year-long randomized controlled trial among community-dwelling older people.
      Patient records at the Central Finland Central Hospital were reviewed (in the fall of 2004–2005 and throughout 2008–2010) to recruit community-dwelling people older than 60 years who had been operated on for femoral neck or trochanteric fracture. All potential patients were informed about the study (N=748). Those willing to participate were interviewed over the telephone or met during the inpatient period at the health care center to ensure suitability (N=268). Exclusion criteria were inability to move outdoors without assistance from another person, amputation of a lower limb, severe progressive or neurologic diseases, alcoholism, and severe memory problems (Mini-Mental State Examination score<19).
      • Folstein M.F.
      • Folstein S.E.
      • McHugh P.R.
      “Mini-mental state”: a practical method for grading the cognitive state of patients for the clinician.
      Of the 149 eligible patients, 130 were included in the present analyses on the basis of an additional criterion of having experienced a hip fracture due to a low-impact fall, which may exacerbate the perception of lack of balance confidence. The ethical committee of the local health care district approved both of the study protocols. Participants gave their written informed consent prior to the assessments. The assessments were performed 6 weeks to 7.5 years after the fracture.

      Assessment

      A physician and research nurse performed a thorough clinical examination to assess general health status. Details of the fracture and repair (internal fixation vs. arthroplasty) and the number of chronic conditions (present for at least 3 months) were confirmed according to a questionnaire and medical records. Time since fracture was calculated as the number of days between the date of fracture and the date of assessments.
      Data collection of the following measures was performed by trained research assistants. Balance confidence in carrying out activities without becoming unsteady was assessed by interview using a modified Finnish version of the ABC scale.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      In this modified version, items 14 and 15 regarding escalators in the original scale were replaced with 2 items on “riding on a bicycle in a street with light traffic/in a heavily trafficked street with no bike path.” Bicycling was a more relevant activity for Finnish older people because large malls with escalators were very uncommon until recently. Subjects were asked to report their confidence levels when carrying out 16 activities, including those performed outdoors. Each activity was rated from 1 (no confidence) to 10 (total confidence); total score ranged from 16 to 160. The ABC scale was reported to be valid and reliable in older populations.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      In addition, a close relationship between the fear of falls and the lack of balance confidence has been shown.
      • Hadjistavropoulos T.
      • Delbaere K.
      • Fitzgerald T.D.
      Reconceptualizing the role of fear of falling and balance confidence in fall risk.
      Functional balance was measured using the Finnish translation of the Berg Balance Scale (BBS),
      • Berg K.O.
      • Wood-Dauphinee S.L.
      • Williams J.I.
      • Maki B.
      Measuring balance in the elderly: validation of an instrument.
      which evaluates the ability to perform 14 tasks related to the subject's skills such as to sit down, stand up, reach forward, turn 360 degrees, and stand on 1 leg. Each task was rated from 0 (incapable) to 4 (safe and independent); total score ranged from 0 to 56. BBS had high intra- and interrater reliability.
      • Steffen T.M.
      • Hacker T.A.
      • Mollinger L.
      Age- and gender-related test performance in community-dwelling elderly people: Six-Minute Walk Test, Berg Balance Scale, Timed Up & Go Test, and gait speeds.
      Participants were categorized as having good and poorer balance performance on the basis of a cutoff point of 45 points, which has been used to predict falls.
      • Berg K.O.
      • Wood-Dauphinee S.L.
      • Williams J.I.
      • Maki B.
      Measuring balance in the elderly: validation of an instrument.
      Participants were allowed to use their assistive device commonly used for walking indoors during mobility tests. Self-preferred walking speed (m/s) was calculated from the shortest time to walk 10 meters, assessed using photocells.a Three meters was allowed for acceleration and deceleration. This test has been shown to be valid and reliable.
      • Sipila S.
      • Multanen J.
      • Kallinen M.
      • Era P.
      • Suominen H.
      Effects of strength and endurance training on isometric muscle strength and walking speed in elderly women.
      Participants were grouped into good, fair, and poorer mobility on the basis of cutoff points of 1.0 and 0.8 meters per second that have been used to predict falls.
      • Studenski S.
      • Perera S.
      • Patel K.
      • et al.
      Gait speed and survival in older adults.
      • Bohannon R.W.
      • Williams Andrews A.
      Normal walking speed: a descriptive meta-analysis.
      The modified Timed-Up-and-Go (TUG) test measures the time it takes to rise from a chair, walk 2.44 meters as fast as possible, turn around a cone, and return to the chair.
      • Podsiadlo D.
      • Richardson S.
      The timed “up & go”: a test of basic functional mobility for frail elderly persons.
      • Rose D.J.
      • Jones C.J.
      • Lucchese N.
      Predicting the probability of falls in community-residing older adults using the 8-foot up-and-go: a new measure of functional mobility.
      • Rikli R.E.
      • Jones C.J.
      Development and validation of a functional fitness test for community-residing older adults.
      The shortest time of 2 trials, measured using a stopwatch, was used for analyses. The TUG test is valid and reliable for assessing mobility.
      • Rikli R.E.
      • Jones C.J.
      Development and validation of a functional fitness test for community-residing older adults.
      Participants were grouped into good, fair, and poorer mobility on the basis of cutoff points of 8.5
      • Rose D.J.
      • Jones C.J.
      • Lucchese N.
      Predicting the probability of falls in community-residing older adults using the 8-foot up-and-go: a new measure of functional mobility.
      and 15
      • Nordin E.
      • Lindelof N.
      • Rosendahl E.
      • Jensen J.
      • Lundin-Olsson L.
      Prognostic validity of the timed up-and-go test, a modified get-up-and-go test, staff's global judgement and fall history in evaluating fall risk in residential care facilities.
      seconds that have been used to predict falls.
      Self-reported mobility was assessed using a questionnaire. Participants were asked about perceived difficulty to walk outdoors and to climb 1 flight of stairs. The response categories were as follows: (1) no difficulty, (2) some difficulty, (3) major difficulty, (4) unable without help from another person, and (5) unable even with help. Because of low frequency in categories 3 to 5, they were joined for the analyses (“major difficulty or unable”).
      • Laukkanen P.
      • Heikkinen E.
      • Kauppinen M.
      Muscle strength and mobility as predictors of survival in 75-84-year-old people.
      Present level of physical activity was assessed with a self-report scale by Grimby
      • Grimby G.
      Physical activity and muscle training in the elderly.
      with slight modifications. The highest category of the initial scale was divided into 2 categories, separating those participating in regular exercise fitness activities from those active in competitive sports. The 7-point scale ranged from 1 (mostly sitting) to 7 (participation in competitive sports). Categories 4 to 7 were combined because of low frequencies, thus leaving 4 groups: (1) mostly sitting, (2) light physical activity, such as light household tasks; (3) moderate physical activity for less than 3 hours a week, such as walking longer distance and domestic work; and (4) moderate activity for more than 4 hours a week and/or more strenuous activity multiple times a week.
      Maximal voluntary isometric knee extension strength of the fractured leg was assessed using an adjustable dynamometer chair.b The ankle was attached to a strain-gauge system with the knee angle fixed at 60 degrees from full extension. Participants were encouraged to extend the leg as forcefully as possible. After 2 to 3 practice trials, the highest force of at least 3 measurements was used for analysis. Each contraction was maintained for 2 to 3 seconds. The test has been shown to be valid and reliable.
      • Rantanen T.
      • Era P.
      • Heikkinen E.
      Physical activity and the changes in maximal isometric strength in men and women from the age of 75 to 80 years.

      Statistical Analysis

      Participants with missing variables in knee extension strength (n=15), walking (n=8), TUG (n=13), and BBS (n=6) tests were dropped from the respective analysis only. BBS score, walking speed, and TUG test values were analyzed as continuous as well as categorical variables on the basis of cutoff points used to predict falls.
      Variable distribution was tested with Kolmogorov-Smirnov tests. Group differences were tested with independent t tests and χ2 tests. Spearman (ρ) and Pearson (r) correlation coefficients were calculated for relationships between ABC scale score, measures of mobility and balance performance, and perceived mobility limitation as well as confounders. Fracture repair type was not significantly (P>.05) associated with any mobility or balance measure and was therefore not included in multivariable analyses. Univariate general linear models were used to compare groups on the basis of categorized mobility and balance performance measures and perceived mobility limitation. Each model included ABC scale score (crude model) and was adjusted for (1) age, sex, time since hip fracture, and number of chronic diseases and in addition either (2) level of physical activity or (3) knee extension strength of the fractured limb. Separate receiver operating characteristic curves were drawn for the ABC scale score to identify those with poorer mobility and balance performance, or major difficulty in perceived mobility measures. For each measure, the optimal cutoff point(s) (highest sensitivity and specificity) was determined. These cutoff points were then used in sensitivity and specificity analyses to choose the cutoff point most suitable to identify those with mobility and balance limitation across outcomes. Finally, the cutoff score identified was used to predict mobility and balance limitation in logistic regression analyses. Odds ratios and 95% confidence intervals of crude (unadjusted) models were reported. PASW Statistics 18c was used for the statistical analyses, and statistical significance was set at P≤.05.

      Results

      Table 1 shows the participants' characteristics. Their average age ± SD was 77.6±7.2 years, and the majority were women. On average, 1.5±1.9 years had passed since the hip fracture.
      Table 1Means ± SD or Prevalence of the Participant Characteristics and Spearman Correlation Coefficients of Each Measure With the ABC Scale
      CharacteristicsMean ± SDρP
      Age (y)77.6±7.2.37
      Pearson correlation coefficients.
      <.001
      Time since fracture (y)1.5±2.0.07.437
      No. of chronic diseases (n)3.4±1.9−.29.001
      Knee extension strength fractured leg (N)202.3±91.2.40
      Pearson correlation coefficients.
      <.001
      BBS score (p)43.3±9.7.72<.001
      TUG test time (s)15.0±10.3−.56<.001
      Walking speed (m/s)0.9±0.2.51
      Pearson correlation coefficients.
      <.001
      ABC scale score (p)89.2±32.51.00NA
      n (%)ρP
      Sex (female)98 (75.4)−.05.613
      Fracture repair−.03.668
       Internal fixation60 (46.2)NANA
       Hemiarthroplasty57 (43.8)NANA
       Total arthroplasty13 (10.0)NANA
      Physical activity.47<.001
       Mostly sitting32 (24.6)NANA
       Low/moderate physical activity67 (51.5)NANA
       Moderate physical activity ≤3h/wk23 (17.7)NANA
       Moderate activity ≥4h/wk or more strenuous7 (5.4)NANA
      NOTE. N=130.
      Abbreviation: NA, not applicable.
      low asterisk Pearson correlation coefficients.

      Correlation Analyses

      Correlation coefficients between the ABC scale score and continuous mobility and balance performance measures indicated that better performance (higher score; for TUG test lower score) was associated with higher balance confidence (higher ABC scale score) (see table 1). Similar correlations were found between the ABC scale score and categorized performance-based measures; ρ=.60 (P<.001) for BBS, ρ=.48 (P<.001) for TUG test, and ρ=−.47 (P<.001) for walking speed, respectively. For the self-reported measures, less difficulty was related to higher balance confidence; the correlation coefficients with the ABC scale score were ρ=−.54 (P<.001) for ability to walk outdoors and ρ=−.57 (P<.001) for stair climb ability, respectively.
      Group differences were calculated for all confounding variables (data not shown). Those with poorer walking speed, TUG test score, and BBS score and those with perceived mobility limitation were significantly older (P≤.014) and had lower levels of physical activity (P<.001) and muscle strength (P≤.005) than those with better functioning. For those with poorer walking speed, TUG test scores, and perceived limitation to walk outdoors, significantly less time had passed since the hip fracture (P≤.041). Those with poorer TUG test scores and BBS scores and those with perceived mobility limitation had a higher number of chronic diseases (P≤.029) than did those with better functioning. Lower ABC scale score correlated significantly with higher age (r=.37, P<.001) and number of diseases (ρ=−.29, P=.001) and lower level of physical activity (ρ=.47, P<.001) and muscle strength (ρ=.40, P<.001) (see table 1).

      Multivariable Analyses

      Figure 1 shows a clear gradient of decreasing ABC scale scores in groups with poorer mobility and balance performance and perceived mobility limitation. Group differences also remained significant (P<.026) after adjustment for age, sex, time since hip fracture, and the number of chronic diseases, as well as after additional adjustment for level of physical activity or knee extension strength in the fractured limb (table 2). Level of physical activity and knee extension strength attenuated the relationship between the ABC scale score and all mobility and balance measures; however, the relationships remained significant.
      Figure thumbnail gr1
      Fig 1Marginal means and 95% confidence intervals of the ABC scale in the mobility and balance groups derived from crude univariate models.
      Table 2Differences in Mean ABC Scale Tested With Adjusted Univariate Models for the Mobility and Balance Performance Groups Based on Previously Reported Cutoff Values and the Groups With Perceived Mobility Limitation
      Grouping VariableABC ScalePhysical ActivityKE
      KE is knee extension strength of the fractured leg.
      Walk outdoors
       Model 1<.001
       Model 2<.001.001
       Model 3<.001.007
      Climb stairs
       Model 1<.001
       Model 2<.001.004
       Model 3<.001.025
      BBS
       Model 1<.001
       Model 2<.001.001
       Model 3<.001.014
      TUG test
       Model 1.001
       Model 2.026.008
       Model 3.014.042
      Walking speed
       Model 1<.001
       Model 2.002.011
       Model 3.002.096
      low asterisk KE is knee extension strength of the fractured leg.

      Sensitivity Analysis

      Receiver operating characteristic curves of each mobility and balance performance or perceived mobility limitation measure with the ABC scale score suggested several potential cutoff points: 68.5 (ability to walk outdoors and walking speed), 76.5 (walking speed and TUG test), 78 (ability to walk outdoors and climb stairs), 80.5 (walking speed), 84.5 (ability to climb stairs and TUG test), and 85.5 (BBS). All were used in the following sensitivity and specificity analyses to identify those with poorer mobility and balance performance and perceived mobility limitation for each measure. Using 84.5 points for cutoff rendered good sensitivity (≥.73) and specificity (≥.70) across all measures (table 3). In logistic regression analyses, those with an ABC scale sum score <85 points had an odds ratio of 18.7 (95% confidence interval 6.0–58.0) for having major outdoors walking difficulty and 11.7 (4.6–29.9) for major stair climb difficulty. For the performance-based tests, the odds ratios were 12.6 (5.3–29.8) for BBS, 7.3 (3.0–17.8) for the TUG test, and 6.3 (2.6–15.0) for walking speed, respectively.
      Table 3Sensitivity and Specificity Analyses Using 85 Points as Cutoff Value for the ABC Scale (to Identify Those With Poorer Mobility and Balance Performance or Perceived Mobility Limitation)
      Outcome VariableABC Scale ScoreABC Scale Score <85
      <85≥85SensitivitySpecificity
      Walk outdoors.89.71
       No difficulty624
       Some difficulty2141
       Major difficulty/unable314
      Climb stairs.83.71
       No difficulty836
       Some difficulty1726
       Major difficulty/unable337
      BBS.78.78
       Good balance1554
       Poorer balance4212
      TUG test.73.70
       Good mobility625
       Fair mobility1831
       Poorer mobility2710
      Walking speed.76.70
       Good mobility1136
       Fair mobility1423
       Poorer mobility289

      Discussion

      Our study shows that balance confidence was associated with a range of measures of mobility and balance performance and perceived mobility limitation in older people after a fall-related hip fracture. The relationships found also remained significant after considerable adjustment. An ABC scale score <85 points identified most participants with mobility and balance limitation across the different measures. The ABC scale may be useful for clinicians to identify hip fracture patients with or at risk for mobility and balance limitation. Addressing lack of balance confidence together with improving mobility and balance performance by physical rehabilitation may positively affect the potential for functional recovery of hip fracture patients.
      In relatively healthy populations of older people, a reduced ABC scale score, indicating lack of confidence to perform mobility tasks without loss of balance, has been associated with reduced performance as measured in walking speed,
      • Talley K.M.
      • Wyman J.F.
      • Gross C.R.
      Psychometric properties of the Activities-specific Balance Confidence scale and the survey of activities and fear of falling in older women.
      • Reelick M.F.
      • van Iersel M.B.
      • Kessels R.P.
      • Rikkert M.G.
      The influence of fear of falling on gait and balance in older people.
      TUG test,
      • Talley K.M.
      • Wyman J.F.
      • Gross C.R.
      Psychometric properties of the Activities-specific Balance Confidence scale and the survey of activities and fear of falling in older women.
      • Schepens S.
      • Goldberg A.
      • Wallace M.
      The short version of the Activities-specific Balance Confidence (ABC) scale: its validity, reliability, and relationship to balance impairment and falls in older adults.
      and BBS.
      • Talley K.M.
      • Wyman J.F.
      • Gross C.R.
      Psychometric properties of the Activities-specific Balance Confidence scale and the survey of activities and fear of falling in older women.
      The mean ABC scale score in our study, when converted to a scale from 0% to 100% (being 55), was similar as the means in 2 studies of patients about 4 months after hip fracture (being 59 and 61, respectively).
      • Whitehead C.
      • Miller M.
      • Crotty M.
      Falls in community-dwelling older persons following hip fracture: impact on self-efficacy, balance and handicap.
      • Kline Mangione K.
      • Craik R.L.
      • Lopopolo R.
      • Tomlinson J.D.
      • Brenneman S.K.
      Predictors of gait speed in patients after hip fracture.
      In addition, the associations with BBS (r=.77)
      • Whitehead C.
      • Miller M.
      • Crotty M.
      Falls in community-dwelling older persons following hip fracture: impact on self-efficacy, balance and handicap.
      and gait speed (r>0.6)
      • Whitehead C.
      • Miller M.
      • Crotty M.
      Falls in community-dwelling older persons following hip fracture: impact on self-efficacy, balance and handicap.
      • Kline Mangione K.
      • Craik R.L.
      • Lopopolo R.
      • Tomlinson J.D.
      • Brenneman S.K.
      Predictors of gait speed in patients after hip fracture.
      were very similar. Previous studies using other measures of fear of falling or balance confidence have shown relationships with TUG test
      • Oude Voshaar R.C.
      • Banerjee S.
      • Horan M.
      • et al.
      Fear of falling more important than pain and depression for functional recovery after surgery for hip fracture in older people.
      and self-reported mobility measures in hip fracture patients.
      • Oude Voshaar R.C.
      • Banerjee S.
      • Horan M.
      • et al.
      Fear of falling more important than pain and depression for functional recovery after surgery for hip fracture in older people.
      • McKee K.J.
      • Orbell S.
      • Austin C.A.
      • et al.
      Fear of falling, falls efficacy, and health outcomes in older people following hip fracture.
      Our results showed that the association between the ABC scale score and mobility and postural balance occurred across different self-reported and performance-based measures.
      Lajoie and Gallagher
      • Lajoie Y.
      • Gallagher S.P.
      Predicting falls within the elderly community: comparison of postural sway, reaction time, the Berg balance scale and the Activities-specific Balance Confidence (ABC) scale for comparing fallers and non-fallers.
      have previously determined a cutoff score for the ABC scale. In their study, a score of less than 67% (ie, 107 points) on the ABC scale increased the risk for falls in relatively healthy older people. Our population with a previous fall-related hip fracture had lower balance confidence (two thirds scored below 107 points). Therefore, we determined a new cutoff point to identify persons with mobility and balance limitation after a fall-related hip fracture. Those with an ABC scale score <85 points had a 6 to 18 times increased risk of having poor mobility and balance performance or perceived mobility limitation than those with higher ABC scale scores. The association between balance confidence, mobility and balance performance, or perceived mobility limitation was independent of time since fracture. This may support the hypothesis that poor balance confidence may implicate poorer recovery potential from an acute event
      • Denkinger M.D.
      • Igl W.
      • Lukas A.
      • et al.
      Relationship between fear of falling and outcomes of an inpatient geriatric rehabilitation population—fear of the fear of falling.
      such as hip fracture.
      The ABC scale is a relatively quick and easy tool to administer.
      • Powell L.E.
      • Myers A.M.
      The Activities-Specific Balance Confidence (ABC) scale.
      Identifying older hip fracture patients with low balance confidence and at risk for mobility and balance limitation may be clinically relevant. In our study, the ABC scale had an independent association with all measures of mobility and balance performance and perceived mobility limitation. Early identification of hip fracture patients at risk may also have an impact on other health outcomes, such as new falls, disability, and loss of independence. The ABC scale may also be suitable in the time-pressured clinical practice.
      Early physical rehabilitation, including progressive resistance training or other physical exercises, may prevent or reduce the major functional decline associated with hip fracture.
      • Sylliaas H.
      • Brovold T.
      • Wyller T.B.
      • Bergland A.
      Progressive strength training in older patients after hip fracture: a randomised controlled trial.
      • Binder E.F.
      • Brown M.
      • Sinacore D.R.
      • Steger-May K.
      • Yarasheski K.E.
      • Schechtman K.B.
      Effects of extended outpatient rehabilitation after hip fracture: a randomized controlled trial.
      In addition, mobility and balance performance can be improved by different physical interventions in healthy older people (for review, see American College of Sports Medicine et al
      • Chodzko-Zajko W.J.
      • Proctor D.N.
      • et al.
      American College of Sports Medicine
      American College of Sports Medicine position stand: exercise and physical activity for older adults.
      ) as well as in clinical populations (for review, see Rydwik et al
      • Rydwik E.
      • Frandin K.
      • Akner G.
      Effects of physical training on physical performance in institutionalised elderly patients (70+) with multiple diagnoses.
      ). Based on the close relationship between physical performance and balance confidence, and the risk appraisal theory,
      • Hadjistavropoulos T.
      • Delbaere K.
      • Fitzgerald T.D.
      Reconceptualizing the role of fear of falling and balance confidence in fall risk.
      • Martin R.R.
      • Hadjistavropoulos T.
      • McCreary D.R.
      Fear of pain and fear of falling among younger and older adults with musculoskeletal pain conditions.
      intervention aiming to improve physical function may also improve balance confidence. In hip fracture patients attending inpatient rehabilitation, no relationship between change in the ABC scale score and change in physical function was observed
      • Petrella R.J.
      • Payne M.
      • Myers A.
      • Overend T.
      • Chesworth B.
      Physical function and fear of falling after hip fracture rehabilitation in the elderly.
      and a weak association was found with change in dynamic balance after exercise training in older people residing in retirement villages.
      • Cyarto E.V.
      • Brown W.J.
      • Marshall A.L.
      • Trost S.G.
      Comparative effects of home- and group-based exercise on balance confidence and balance ability in older adults: cluster randomized trial.
      There is some evidence that the fear of falling may be reduced by different interventions in community-dwelling older populations.
      • Zijlstra G.A.
      • van Haastregt J.C.
      • van Rossum E.
      • van Eijk J.T.
      • Yardley L.
      • Kempen G.I.
      Interventions to reduce fear of falling in community-living older people: a systematic review.
      However, systematic reviews in older hip fracture patients of multidisciplinary interventions and interventions aiming to improve both physical and psychological function were not able to demonstrate better outcomes when compared with regular care after hip fracture.
      • Crotty M.
      • Unroe K.
      • Cameron I.D.
      • Miller M.
      • Ramirez G.
      • Couzner L.
      Rehabilitation interventions for improving physical and psychosocial functioning after hip fracture in older people.
      • Handoll H.H.
      • Cameron I.D.
      • Mak J.C.
      • Finnegan T.P.
      Multidisciplinary rehabilitation for older people with hip fractures.

      Study Limitations

      Because of our inclusion criteria (community-dwelling, being able to come to our research center for measurements, being able to walk outdoors independently) participants were relatively well-functioning older people compared with hip fracture patients in general. Generalization of the results should be done with caution. We included older people with a large time range since the fall-related hip fracture (6wk to 7.5y). The time since fracture was related to performance-based mobility and balance measures; however, it did not affect the relationship between the ABC scale score, mobility and balance performance, or perceived mobility limitation. This may suggest that lack of balance confidence persistently affects mobility and balance performance in older people with a history of fall-related hip fracture. The sample size in this study allowed for considerable adjustment. We are therefore confident that the relationship between balance confidence and the different measures of mobility and balance performance and perceived mobility limitation was independent. Because of the cross-sectional study design, the chronological order of lack of balance confidence and limitations in mobility and balance performance and their relationship with the hip fracture event remain unclear. Longitudinal studies are needed to confirm associations and determine cause-effect relationships.

      Conclusions

      In older people with a fall-related hip fracture, an independent relationship exists between balance confidence and a range of performance-based and self-reported mobility and balance performance measures. In this group of older people, a score of <85 points on the ABC scale identified those with mobility and balance limitation. Identification of persons with lack of balance confidence seems clinically relevant as it may compromise functional recovery from the hip fracture. Potentially, rehabilitation may be more effective, when lack of balance confidence is taken into account or targeted. However, further study is needed to develop effective strategies to improve balance confidence and reduce the functional decline associated with hip fracture.
      • a
        Research Laboratory, Department of Health Sciences, Rautpohjankatu 8, University of Jyväskylä, Jyväskylä, Finland.
      • b
        Good Strength, MetiturOy Heinämäentie 7, Jyväskylä, Finland.
      • c
        SPSS Inc, 233 S Wacker Dr, 11th Fl, Chicago, IL 60606.

      References

        • Bandura A.
        Self-efficacy: toward a unifying theory of behavioral change.
        Psychol Rev. 1977; 84: 191-215
        • Powell L.E.
        • Myers A.M.
        The Activities-Specific Balance Confidence (ABC) scale.
        J Gerontol A Biol Sci Med Sci. 1995; 50A: M28-M34
        • Hadjistavropoulos T.
        • Delbaere K.
        • Fitzgerald T.D.
        Reconceptualizing the role of fear of falling and balance confidence in fall risk.
        J Aging Health. 2011; 23: 3-23
        • Lloyd B.D.
        • Williamson D.A.
        • Singh N.A.
        • et al.
        Recurrent and injurious falls in the year following hip fracture: a prospective study of incidence and risk factors from the sarcopenia and hip fracture study.
        J Gerontol A Biol Sci Med Sci. 2009; 64: 599-609
        • Madsen O.R.
        • Lauridsen U.B.
        • Sorensen O.H.
        Quadriceps strength in women with a previous hip fracture: relationships to physical ability and bone mass.
        Scand J Rehabil Med. 2000; 32: 37-40
        • Portegijs E.
        • Kallinen M.
        • Rantanen T.
        • et al.
        Effects of resistance training on lower-extremity impairments in older people with hip fracture.
        Arch Phys Med Rehabil. 2008; 89: 1667-1674
        • Sihvonen S.
        • Kulmala J.
        • Kallinen M.
        • Alen M.
        • Kiviranta I.
        • Sipila S.
        Postural balance and self-reported balance confidence in older adults with a hip fracture history.
        Gerontology. 2009; 55: 630-636
        • Visser M.
        • Harris T.B.
        • Fox K.M.
        • et al.
        Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery.
        J Gerontol A Biol Sci Med Sci. 2000; 55: M434-M440
        • Sherrington C.
        • Lord S.R.
        Increased prevalence of fall risk factors in older people following hip fracture.
        Gerontology. 1998; 44: 340-344
        • Marottoli R.A.
        • Berkman L.F.
        • Cooney Jr, L.M.
        Decline in physical function following hip fracture.
        J Am Geriatr Soc. 1992; 40: 861-866
        • Denkinger M.D.
        • Igl W.
        • Lukas A.
        • et al.
        Relationship between fear of falling and outcomes of an inpatient geriatric rehabilitation population—fear of the fear of falling.
        J Am Geriatr Soc. 2010; 58: 664-673
        • Myers A.M.
        • Fletcher P.C.
        • Myers A.H.
        • Sherk W.
        Discriminative and evaluative properties of the Activities-specific Balance Confidence (ABC) scale.
        J Gerontol A Biol Sci Med Sci. 1998; 53: M287-M294
        • Deshpande N.
        • Metter E.J.
        • Lauretani F.
        • Bandinelli S.
        • Guralnik J.
        • Ferrucci L.
        Activity restriction induced by fear of falling and objective and subjective measures of physical function: a prospective cohort study.
        J Am Geriatr Soc. 2008; 56: 615-620
        • Cumming R.G.
        • Salkeld G.
        • Thomas M.
        • Szonyi G.
        Prospective study of the impact of fear of falling on activities of daily living, SF-36 scores, and nursing home admission.
        J Gerontol A Biol Sci Med Sci. 2000; 55: M299-M305
        • Rantanen T.
        • Avlund K.
        • Suominen H.
        • Schroll M.
        • Frandin K.
        • Pertti E.
        Muscle strength as a predictor of onset of ADL dependence in people aged 75 years.
        Aging Clin Exp Res. 2002; 14: 10-15
        • Sylliaas H.
        • Brovold T.
        • Wyller T.B.
        • Bergland A.
        Progressive strength training in older patients after hip fracture: a randomised controlled trial.
        Age Ageing. 2011; 40: 221-227
        • Binder E.F.
        • Brown M.
        • Sinacore D.R.
        • Steger-May K.
        • Yarasheski K.E.
        • Schechtman K.B.
        Effects of extended outpatient rehabilitation after hip fracture: a randomized controlled trial.
        JAMA. 2004; 292: 837-846
        • Talley K.M.
        • Wyman J.F.
        • Gross C.R.
        Psychometric properties of the Activities-specific Balance Confidence scale and the survey of activities and fear of falling in older women.
        J Am Geriatr Soc. 2008; 56: 328-333
        • Schepens S.
        • Goldberg A.
        • Wallace M.
        The short version of the Activities-specific Balance Confidence (ABC) scale: its validity, reliability, and relationship to balance impairment and falls in older adults.
        Arch Gerontol Geriatr. 2010; 51: 9-12
        • Reelick M.F.
        • van Iersel M.B.
        • Kessels R.P.
        • Rikkert M.G.
        The influence of fear of falling on gait and balance in older people.
        Age Ageing. 2009; 38: 435-440
        • Visschedijk J.
        • Achterberg W.
        • Van Balen R.
        • Hertogh C.
        Fear of falling after hip fracture: a systematic review of measurement instruments, prevalence, interventions, and related factors.
        J Am Geriatr Soc. 2010; 58: 1739-1748
        • Portegijs E.
        • Rantanen T.
        • Kallinen M.
        • et al.
        Lower-limb pain, disease, and injury burden as determinants of muscle strength deficit after hip fracture.
        J Bone Joint Surg Am. 2009; 91: 1720-1728
        • Sipila S.
        • Salpakoski A.
        • Edgren J.
        • et al.
        Promoting mobility after hip fracture (ProMo): study protocol and selected baseline results of a year-long randomized controlled trial among community-dwelling older people.
        BMC Musculoskelet Disord. 2011; 12: 277
        • Folstein M.F.
        • Folstein S.E.
        • McHugh P.R.
        “Mini-mental state”: a practical method for grading the cognitive state of patients for the clinician.
        J Psychiatr Res. 1975; 12: 189-198
      1. Mänty M. Sihvonen S. Hulkko T. Lounamaa A. Iäkkäiden henkilöiden kaatumistapaturmat Opas kaatumisten ja murtumien ehkäisyyn. 2nd ed. Kansanterveyslaitoksen julkaisuja, 2007 (Accessed May 25, 2012)
        • Berg K.O.
        • Wood-Dauphinee S.L.
        • Williams J.I.
        • Maki B.
        Measuring balance in the elderly: validation of an instrument.
        Can J Public Health. 1992; 83: S7-S11
        • Steffen T.M.
        • Hacker T.A.
        • Mollinger L.
        Age- and gender-related test performance in community-dwelling elderly people: Six-Minute Walk Test, Berg Balance Scale, Timed Up & Go Test, and gait speeds.
        Phys Ther. 2002; 82: 128-137
        • Sipila S.
        • Multanen J.
        • Kallinen M.
        • Era P.
        • Suominen H.
        Effects of strength and endurance training on isometric muscle strength and walking speed in elderly women.
        Acta Physiol Scand. 1996; 156: 457-464
        • Studenski S.
        • Perera S.
        • Patel K.
        • et al.
        Gait speed and survival in older adults.
        JAMA. 2011; 305: 50-58
        • Bohannon R.W.
        • Williams Andrews A.
        Normal walking speed: a descriptive meta-analysis.
        Physiotherapy. 2011; 97: 182-189
        • Podsiadlo D.
        • Richardson S.
        The timed “up & go”: a test of basic functional mobility for frail elderly persons.
        J Am Geriatr Soc. 1991; 39: 142-148
        • Rose D.J.
        • Jones C.J.
        • Lucchese N.
        Predicting the probability of falls in community-residing older adults using the 8-foot up-and-go: a new measure of functional mobility.
        J Aging Phys Act. 2002; 10: 466-475
        • Rikli R.E.
        • Jones C.J.
        Development and validation of a functional fitness test for community-residing older adults.
        J Aging Phys Act. 1999; 7: 129-161
        • Nordin E.
        • Lindelof N.
        • Rosendahl E.
        • Jensen J.
        • Lundin-Olsson L.
        Prognostic validity of the timed up-and-go test, a modified get-up-and-go test, staff's global judgement and fall history in evaluating fall risk in residential care facilities.
        Age Ageing. 2008; 37: 442-448
        • Laukkanen P.
        • Heikkinen E.
        • Kauppinen M.
        Muscle strength and mobility as predictors of survival in 75-84-year-old people.
        Age Ageing. 1995; 24: 468-473
        • Grimby G.
        Physical activity and muscle training in the elderly.
        Acta Med Scand Suppl. 1986; 711: 233-237
        • Rantanen T.
        • Era P.
        • Heikkinen E.
        Physical activity and the changes in maximal isometric strength in men and women from the age of 75 to 80 years.
        J Am Geriatr Soc. 1997; 45: 1439-1445
        • Whitehead C.
        • Miller M.
        • Crotty M.
        Falls in community-dwelling older persons following hip fracture: impact on self-efficacy, balance and handicap.
        Clin Rehabil. 2003; 17: 899-906
        • Kline Mangione K.
        • Craik R.L.
        • Lopopolo R.
        • Tomlinson J.D.
        • Brenneman S.K.
        Predictors of gait speed in patients after hip fracture.
        Physiother Can. 2008; 60: 10-18
        • Oude Voshaar R.C.
        • Banerjee S.
        • Horan M.
        • et al.
        Fear of falling more important than pain and depression for functional recovery after surgery for hip fracture in older people.
        Psychol Med. 2006; 36: 1635-1645
        • McKee K.J.
        • Orbell S.
        • Austin C.A.
        • et al.
        Fear of falling, falls efficacy, and health outcomes in older people following hip fracture.
        Disabil Rehabil. 2002; 24: 327-333
        • Lajoie Y.
        • Gallagher S.P.
        Predicting falls within the elderly community: comparison of postural sway, reaction time, the Berg balance scale and the Activities-specific Balance Confidence (ABC) scale for comparing fallers and non-fallers.
        Arch Gerontol Geriatr. 2004; 38: 11-26
        • Chodzko-Zajko W.J.
        • Proctor D.N.
        • et al.
        • American College of Sports Medicine
        American College of Sports Medicine position stand: exercise and physical activity for older adults.
        Med Sci Sports Exerc. 2009; 41: 1510-1530
        • Rydwik E.
        • Frandin K.
        • Akner G.
        Effects of physical training on physical performance in institutionalised elderly patients (70+) with multiple diagnoses.
        Age Ageing. 2004; 33: 13-23
        • Martin R.R.
        • Hadjistavropoulos T.
        • McCreary D.R.
        Fear of pain and fear of falling among younger and older adults with musculoskeletal pain conditions.
        Pain Res Manag. 2005; 10: 211-219
        • Petrella R.J.
        • Payne M.
        • Myers A.
        • Overend T.
        • Chesworth B.
        Physical function and fear of falling after hip fracture rehabilitation in the elderly.
        Am J Phys Med Rehabil. 2000; 79: 154-160
        • Cyarto E.V.
        • Brown W.J.
        • Marshall A.L.
        • Trost S.G.
        Comparative effects of home- and group-based exercise on balance confidence and balance ability in older adults: cluster randomized trial.
        Gerontology. 2008; 54: 272-280
        • Zijlstra G.A.
        • van Haastregt J.C.
        • van Rossum E.
        • van Eijk J.T.
        • Yardley L.
        • Kempen G.I.
        Interventions to reduce fear of falling in community-living older people: a systematic review.
        J Am Geriatr Soc. 2007; 55: 603-615
        • Crotty M.
        • Unroe K.
        • Cameron I.D.
        • Miller M.
        • Ramirez G.
        • Couzner L.
        Rehabilitation interventions for improving physical and psychosocial functioning after hip fracture in older people.
        Cochrane Database Syst Rev. 2010; (CD007624)
        • Handoll H.H.
        • Cameron I.D.
        • Mak J.C.
        • Finnegan T.P.
        Multidisciplinary rehabilitation for older people with hip fractures.
        Cochrane Database Syst Rev. 2009; (CD007125)