Rehabilitation in Home Care Is Associated With Functional Improvement and Preferred Discharge

Published:February 05, 2013DOI:https://doi.org/10.1016/j.apmr.2012.12.024

      Abstract

      Objective

      To investigate the impact of physiotherapy (PT) and occupational therapy (OT) services on long-stay home care patients with musculoskeletal disorders.

      Design

      Observational study.

      Setting

      Home care programs.

      Participants

      All long-stay home care patients between 2003 and 2008 (N=99,764) with musculoskeletal disorders who received a baseline Resident Assessment Instrument for Home Care assessment, 1 follow-up assessment, and had discharge or death records.

      Interventions

      PT and OT.

      Main Outcome Measures

      The effects of PT and OT services on transitions in functional state, discharge from home care with service plans complete, institutionalization, and death were assessed via multistate Markov models.

      Results

      Home care patients with deficiencies in instrumental activities of daily living and/or activities of daily living at baseline and who received home-based rehabilitation had significantly increased odds of showing functional improvements by their next assessment (for a state 3 to state 2 transition: odds ratio [OR]=1.17; 95% confidence interval [CI], 1.10–1.26; P<.0001; for a state 2 to state 1 transition: OR=1.36; 95% CI, 1.14–1.61; P=.0005). Receipt of PT/OT also significantly reduced the odds of mortality and institutionalization in this group.

      Conclusions

      With increasing numbers of older adults with chronic conditions and limited funding for health care services, it is essential to provide the right services at the right time in a cost-effective manner. Long-stay home care patients who receive rehabilitation at home have improved outcomes and lower utilization of costly health services. Our findings suggest that investment in PT and OT services for relatively short periods may provide savings to the health care system over the longer term.

      Keywords

      List of abbreviations:

      ADL (activities of daily living), CHESS (Changes in Health, End-Stage Disease, and Signs and Symptoms Scale), CI (confidence interval), CPS (Cognitive Performance Scale), DRS (Depression Rating Scale), HR (hazard ratio), IADL (instrumental activities of daily living), MSK (musculoskeletal), OR (odds ratio), OT (occupational therapy), PT (physiotherapy), RAI-HC (Resident Assessment Instrument for Home Care)
      Home care is currently the fastest growing portion of the health system in Canada.

      Commission on the Future of Health Care in Canada (Romanow commission). Building on values: the future of health care in Canada. Saskatoon: Commission on the Future of Health Care in Canada; 2002. Available at: http://publications.gc.ca/collections/Collection/CP32-85-2002E.pdf. Accessed July 12, 2012.

      With increased pressure for a more economical system—including early discharge, and reduction of alternate level of care beds and emergency department wait times—heightened morbidity is required for institutional admission, and patients with more complex medical problems are being managed within the community.

      Ontario Health Coalition. Still waiting: an assessment of Ontario’s home care system after two decades of restructuring. Toronto: Ontario Health Coalition; 2011. Available at: www.web.net/∼ohc/homecare2011finalreport.pdf. Accessed July 12, 2012.

      Shamian et al
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      suggested that a comprehensive approach to home and community care is essential to sustain this shift. The cost-effectiveness of home care has been a matter of controversy for many years,
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      The evaluation of the National Long Term Care Demonstration. 8. The effect of channeling on health and long-term care costs.
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      Hollander M, Chappell N. Final report of the national evaluation of the cost-effectiveness of home care. Victoria: Hollander Analytical Services Ltd, University of Victoria Centre on Aging; 2002. Available at: http://www.coag.uvic.ca/resources/publications/reports/hollander_synthesis.pdf. Accessed July 12, 2012.

      concluded that home care is a cost-effective alternative to residential care. Despite the recognized benefits of home care, it continues to be insufficiently funded to meet the needs of the Canadian population. Specifically, recent strains on the home care system have resulted in inadequate and rationed services, inequitable access to care, staffing shortages, and privatization of services.

      Ontario Health Coalition. Still waiting: an assessment of Ontario’s home care system after two decades of restructuring. Toronto: Ontario Health Coalition; 2011. Available at: www.web.net/∼ohc/homecare2011finalreport.pdf. Accessed July 12, 2012.

      A primary goal of providing rehabilitation services within the home is to allow individuals to maintain or improve their physical functioning, quality of life, and overall independence while remaining in the community longer.
      • Patrick L.
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      • Rexroth D.
      Medical complexity and rehabilitation efficiency in geriatric inpatients.
      With changing population demographics, community rehabilitation is a potential strategy for effective management of the aging population. In addition to direct patient benefits such as functional ability and mortality,
      • Bachmann S.
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      State of the art in geriatric rehabilitation. Part I: review of frailty and comprehensive geriatric assessment.
      it also has the potential to lead to system improvements including more appropriate resource use and avoidance of institutional placements.
      • Gill T.M.
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      • Gottschalk M.
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      • Allore H.
      • Byers A.
      A program to prevent functional decline in physically frail, elderly persons who live at home.
      • Giusti A.
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      • Razzano M.
      • et al.
      An analysis of the feasibility of home rehabilitation among elderly people with proximal femoral fractures.
      • Crotty M.
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      • Miller M.
      • Gray S.
      Patient and caregiver outcomes 12 months after home-based therapy for hip fracture: a randomized controlled trial.
      • Kuisma R.
      A randomized, controlled comparison of home versus institutional rehabilitation of patients with hip fracture.
      • Gitlin L.N.
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      • Winter L.
      • Dennis M.P.
      • Schulz R.
      Effect of an in-home occupational and physical therapy intervention on reducing mortality in functionally vulnerable older people: preliminary findings.
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      • Dennis M.P.
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      • Schinfeld S.
      • Hauck W.W.
      A randomized trial of a multicomponent home intervention to reduce functional difficulties in older adults.
      Despite these benefits, community-based rehabilitation is often not adequately funded.

      Hepburn B. Health care in Ontario is cracking under stress. Toronto Star 2010 August 5. Available at: http://www.thestar.com/article/844049-hepburn-health-care-in-ontario-is-cracking-under-stress. Accessed September 30, 2010.

      Recent cuts to home-based rehabilitation services—such as the 9% and 24% drop in home visits for physiotherapists and occupational therapists, respectively—have created concerns that there are inadequate resources to sustain increasing demands on rehabilitation services, which may lead to compromised patient care.

      Hepburn B. Health care in Ontario is cracking under stress. Toronto Star 2010 August 5. Available at: http://www.thestar.com/article/844049-hepburn-health-care-in-ontario-is-cracking-under-stress. Accessed September 30, 2010.

      A number of systematic reviews
      • Barnes M.P.
      • Radermacher H.
      Neurological rehabilitation in the community.
      • Catty J.
      • Burns T.
      • Knapp M.
      • et al.
      Home treatment for mental health problems: a systematic review.
      • Langhorne P.
      • Taylor G.
      • Murray G.
      • et al.
      Early supported discharge services for stroke patients: a meta-analysis of individual patients' data.
      • Taylor R.S.
      • Dalal H.
      • Jolly K.
      • Moxham T.
      • Zawada A.
      Home-based versus centre-based cardiac rehabilitation.
      • Stolee P.
      • Lim S.N.
      • Wilson L.
      • Glenny C.
      Inpatient versus home-based rehabilitation for older adults with musculoskeletal disorders: a systematic review.
      have been completed recently that suggest home-based rehabilitation is as good or better than inpatient rehabilitation for postacute rehabilitation in a variety of populations including neurologic, cardiac, stroke, mental health, and musculoskeletal (MSK) patients. Specifically, Stolee et al
      • Stolee P.
      • Lim S.N.
      • Wilson L.
      • Glenny C.
      Inpatient versus home-based rehabilitation for older adults with musculoskeletal disorders: a systematic review.
      systematically reviewed 12 controlled studies comparing home-based and inpatient rehabilitation (outpatient rehabilitation was excluded) for older patients with MSK disorders and found that compared with the inpatient group, patients who received rehabilitation in the home had equal or larger gains in function, cognition, quality of life, and patient satisfaction, as well as decreased mortality and health service use. However, they also found that many of the studies recruited a selective group of postacute patients for their intervention who may have been most likely to benefit from rehabilitation, and that the literature lacked the definitive empirical evidence needed to understand the effect of home-based rehabilitation services on older adults with multimorbidity who were unlikely to meet the criteria for inpatient rehabilitation or who may have indications for physiotherapy (PT) or occupational therapy (OT) services without a recent hospitalization.
      To fill this critical knowledge gap, the current study investigated the effect of home-based rehabilitation services (PT and/or OT [PT/OT]) on the functional ability and discharge disposition for patients with MSK disorders. We used the Resident Assessment Instrument for Home Care (RAI-HC)
      • Morris J.N.
      • Fries B.E.
      • Steel K.
      • et al.
      Comprehensive clinical assessment in community setting: applicability of the MDS-HC.
      data, which offered high quality and comprehensive patient records.
      • Hirdes J.P.
      Addressing the health needs of frail elderly people: Ontario's experience with an integrated health information system.
      A multistate Markov model was used to investigate the transitions from patients’ baseline status or functional “state” at the start of a course of PT/OT treatment at home and their “state” at its completion. This model process provided a useful framework for modeling changes in health status over time, and the comprehensive nature of the RAI-HC assessment provided multiple factors for use in risk adjustment including baseline physical function, activity level, falls, cognitive function, mood, and instability/frailty.

      Methods

       Source of data

      The RAI-HC is one of a suite of standardized assessment tools developed by the international interRAI consortium.
      • Morris J.N.
      • Fries B.E.
      • Steel K.
      • et al.
      Comprehensive clinical assessment in community setting: applicability of the MDS-HC.
      • Gray L.C.
      • Berg K.
      • Fries B.E.
      • et al.
      Sharing clinical information across care settings: the birth of an integrated assessment system.
      • Hirdes J.P.
      • Fries B.E.
      • Morris J.N.
      • et al.
      Integrated health information systems based on the RAI/MDS series of instruments.
      • Hirdes J.P.
      • Ljunggren G.
      • Morris J.N.
      • et al.
      Reliability of the interRAI suite of assessment instruments: a 12-country study of an integrated health information system.
      It is mandated in Ontario and other jurisdictions to collect census-type data on home care patients expected to be on service for more than 60 days. The aim of the instrument is to inform and guide comprehensive care and service planning in community-based settings. It contains more than 300 items measuring cognition, mood and behavior, informal support services, physical functioning, and other patient characteristics. The RAI-HC includes multiple embedded scales such as the Activities of Daily Living (ADL) Hierarchy Scale
      • Morris J.N.
      • Fries B.E.
      • Morris S.A.
      Scaling ADLs within the MDS.
      ; Instrumental Activities of Daily Living (IADL) Scale
      • Morris J.N.
      • Fries B.E.
      • Steel K.
      • et al.
      Comprehensive clinical assessment in community setting: applicability of the MDS-HC.
      ; Changes in Health, End-Stage Disease, and Signs and Symptoms Scale (CHESS)
      • Hirdes J.P.
      • Frijters D.H.
      • Teare G.F.
      The MDS–CHESS scale: a new measure to predict mortality in institutionalized older people.
      ; Depression Rating Scale (DRS)
      • Burrows A.B.
      • Morris J.N.
      • Simon S.E.
      • Hirdes J.P.
      • Phillips C.
      Development of a minimum data set–based depression rating scale for use in nursing homes.
      ; and Cognitive Performance Scale (CPS).
      • Morris J.N.
      • Fries B.E.
      • Mehr D.R.
      • et al.
      MDS Cognitive Performance Scale.
      The RAI-HC data used for this analysis contain all assessments done in the province of Ontario from January 2003 until September 2008. To construct the appropriate dataset we combined 3 Ontario home care and related data-holding sources: RAI-HC assessments, admission and discharge records, and service records. Linked patients (ie, patients whose information was contained on all 3 data sources) were included if they had (1) an RAI-HC baseline assessment coded for at least 1 MSK condition (specifically hip fracture, other fractures, osteoporosis, and arthritis); (2) at least 1 consecutive follow-up assessment within the same admission episode; and (3) a date of discharge or death. Table 1 includes additional information regarding the number of patients and the number of assessments included in the final dataset. Assessment times were measured from the time of start of home care (in days). The baseline assessment was defined as occurring within 3 months of admission to home care. As mandated by interRAI, follow-up assessments are completed every 6 months or earlier in the event of major clinical changes. We restricted attention to persons with an MSK diagnosis listed as the primary or an associated condition. MSK disorders are the primary cause of chronic pain and physical disability in the general population
      • Woolf A.D.
      • Pfleger B.
      Burden of major musculoskeletal conditions..
      and a common target for rehabilitation services in home care. The MSK designation refers to a group of conditions that can affect the bones, joints, muscles, or extra-articular soft tissue.
      • Beers M.H.
      • Porter R.S.
      • Jones T.V.
      • Kaplan J.L.
      • Berkwits M.
      The Merck manual of diagnosis and therapy.
      The RAI-HC requires assessors to check for the presence or absence of the following MSK conditions: hip fracture, other fractures, osteoporosis, and arthritis.
      Table 1Study population
      Steps in Dataset ConstructionNo. of PatientsNo. of AssessmentsNo. of Patient-Admissions
      To get outcome and covariates of interest:
      Total in RAI-HC assessments data file414,5461,043,700
       No. of patients with missing covariates of interest25,603
       Remove patients with missing covariates of interest and remove duplicate entries based on patient ID and assessment date.388,943980,590(1)
      To get discharge/death information:
      Total in admission and discharge records data file898,7831,901,526
       Remove duplicate entries based on patient ID, referral date, admission date, discharge date, discharge reason, and assessment outcome.898,7831,705,586
       Remove entries without discharge date.750,6621,114,550
       Further remove duplicate entries based on patient ID and discharge date.750,6621,078,273(2)
      To determine whether a patient received PT or OT:
      Total in service records data file859,67179,233,196
       Keep entries where type of service provided = 5 or 6.
      5, OT; 6, PT.
      378,4872,981,352(3)
      To combine information from different data files:
      Combine (2) and (3) first.802,2354,059,625
       Keep entries where discharge reason ID is not missing and discharge reason ID ≥0.750,6621,078,273
       Remove patients who have no entries in (1).241,790412,765
       Remove any discharge information collected before the first RAI-HC assessment date.225,920355,160(4)
      Then, combine (1) and (4).388,9431,335,750
       Remove observations that occur after first death entry.388,9431,332,546
       Remove back-to-back discharge entries.388,9431,262,178
       Remove patients with only 1 entry.305,3491,178,584
       Remove patient-admission with only 1 entry.305,3491,152,514362,403(5)
      Take (5)
       Keep patients who met the MSK criteria.175,866689,272209,741
       Keep patient-admission with at least 2 entries.99,764237,557110,497
      Abbreviation: ID, identification.
      5, OT; 6, PT.
      During the study period, some patients had multiple admissions to the home care system; these were treated as separate episodes. Within the period of January 2003 to September 2008, 90,012 (90.2%) individuals had 1 enrollment to home care, 8,852 (8.9%) had 2 engagements with home care, 830 (0.8%) had 3 engagements with home care, and 79 (<0.1%) had 4 or more engagements.
      The total sample included 99,764 long-stay home care patients with MSK disorders who received PT/OT services and had 2 or more consecutive RAI-HC assessments completed within at least 1 engagement with home care, representing approximately one third of home care patients who received RAI-HC assessments. In Ontario, long-stay home care patients are those expected to have stays of 60 days or longer; short-stay patients do not normally receive the RAI-HC assessment.

       Statistical methods

      Multistate processes provide a very useful framework for modeling changes in health status over time and identifying factors that influence these changes. Figure 1 is a state-space diagram composed of 6 states that are defined based on functional status and discharge destination. Dependence was defined using the ADL Hierarchy Scale
      • Morris J.N.
      • Fries B.E.
      • Morris S.A.
      Scaling ADLs within the MDS.
      and the IADL Capacity Scale.
      • Landi F.
      • Tua E.
      • Onder G.
      • et al.
      Minimum data set for home care: a valid instrument to assess frail older people living in the community.
      For both scales, scores greater than 0 indicate dependence in at least 1 activity.
      • Morris J.N.
      • Fries B.E.
      • Morris S.A.
      Scaling ADLs within the MDS.
      Individuals who are home care patients occupy states 1 (independent in ADL and IADL), 2 (independent in ADL but limited in IADL), or 3 (limited function in both ADL and IADL). These represent 3 levels of functional ability and are referred to as transient states because patients can exit them. Movement from state 1 to state 2, state 1 to state 3, or state 2 to state 3 all correspond to a decline in functional ability, whereas transitions in the reverse direction correspond to functional improvement. States 4, 5, and 6 represent potential reasons for discharge and are so-called absorbing states, since transitioning to one of these defines the end of the particular engagement with home care.
      Figure thumbnail gr1
      Fig 1State-space diagram reflecting possible transitions in multistate Markov model. Bolded arrows indicate statistically significant relationships (P<.05) based on multivariate analyses, all favoring improved outcomes or reduced negative outcomes (states 5 or 6). 1Completion of home care services or discharge to different community services. 2No completion of home care services or admission to either hospital or long-term care (LTC).
      To contribute to the analysis, all cases must have complete baseline covariate information at the time of entering into home care. The list of covariates includes age, sex, ADL Hierarchy Scale, falls frequency, CHESS, CPS, DRS, Charlson Crosswalk Comorbidity Index (we did not include the normally assigned points for age in our application of the Charlson Comorbidity Index, as we adjusted for age separately), information on how frequently the patient went out of the house/building in which the patient lived in per week during the last 30 days, and the number of hours of physical activities in the last 3 days. The independent variable of primary interest was whether a patient received PT or OT.
      The statistical analyses were directed at modeling changes in functional ability and were carried out based on a discrete time nonhomogeneous Markov chain model. For clarity and simplification we defined notation for a single individual. Suppose a process can be characterized with a state-space {1, 2, …, K} involving K distinct states. As described above, here each state was defined to represent a distinct health condition (ie, functional ability, discharge, death). Without loss of generality we label the assessment times, t=1, 2, …, and let C denote the last time an individual was observed; this accounts for the fact that different individuals have different durations of follow-up, and that the process ends when a subject is discharged or dies. Let Z(t) indicate the state occupied by an individual of interest at assessment t, so Z(t)=1, 2, … or K. Let Y(t)=I(tC) indicate the individual has not yet left home care or been censored by assessment time t. Let Yk(t)=I(Z(t1)=k) indicate the individual is at risk of a transition out of a particular state k at time t−1. Let Xkl(t)=(1,Xkl1(t),,Xkl,pkl(t)) denote a (pkl+1)×1 vector of possible time-dependent covariates governing the kl transition probability from assessment t-1 to t. Finally, let Nk(t)=(Nk1(t),,NkK(t)), where Nkl(t)=I(Z(t1)=k,Z(t)=l) indicates whether a kl transition occurred between t-1 and t.
      Under the first-order nonhomogeneous Markov model, we let πkl(t)=P(Z(t)=l|Z(t1)=k,Xkl(t)) denote the kl transitional probability for an individual over t-1 to t with covariate vector Xkl(t). The effect of covariates are modeled through generalized logit models
      • McCullagh P.
      • Nelder J.A.
      Generalized linear models.
      of the form
      log(πkl(t)πkk(t))=Xkl(t)βkl
      (1)


      where if lk, then the transition probability is given by
      πkl(t)=exp(Xkl(t)βkl)1+j=1,jkKexp(Xkj(t)βkj),
      (2)


      and the probability of remaining in state k is πkk(t)=1j=1,jkKπkj(t),k=1,,K.
      Two consecutive assessments are required for transitional analyses of this type since we must condition on the initial state. The likelihood is then
      Lt=2T{k=1K(l=1Kπkl(t)Nkl(t))Y¯k(t)}
      (3)


      where Y¯k(t)=Y(t)Yk(t).
      The value of T corresponds to the maximum number of assessments to be considered, and the term Y¯k(t) in the exponent terminates the product as soon as an individual is censored or he/she enters one of the absorbing states because of discharge or death.
      This is a first-order Markov model for which the regression coefficients are log odds ratios reflecting the effect of covariates on the odds of a kl transition versus the odds of remaining in state k. Consider a covariate indicating the presence of a particular condition. If k is a favorable state and l is a less favorable state, if the coefficient of this covariate is negative, then the odds of this transition to the less favorable state are lower among individuals with the condition, and the condition is therefore protective.
      If we let vklr(t)=I(t=r) indicate an assessment time is the rth assessment time, r=3, …, T, then if vkl(t)=(vkl3(t),,vklT(t)) be a (T−2) x 1 vector, we can let
      log(πkl(t)πkk(t))=Xkl(t)βkl+Vkl(t)γkl
      (4)


      where γkl measures the trend in the transition probabilities over time and hence allows for time nonhomogeneous transition probabilities. If one adds an interaction between Xkl and Vkl, then the effect of the covariates can change over time. This expanded model is most useful for checking the adequacy of the reduced model in equation 1, within which constant covariate effects are assumed.
      The precise dates of discharge and death were available, so cause-specific Cox regression models were also fit for the potential reasons for discharge (states 4–6).
      • Lawless J.F.
      Statistical models and methods for lifetime data.
      Cumulative incidence functions were also computed to estimate the probability of discharge by reason, and death as a function of time.
      • Crowder M.J.
      Classical competing risks.
      Time-dependent covariates are used here to reflect the most recent status of the patients with respect to the prognostic variables, and ADL status was carried forward at most 6 months if an assessment was missed. The covariate effects were summarized in this analysis using hazard ratios (HRs), 95% confidence intervals (CIs), and P values. The Markov chain regression analyses were carried out using SAS version 9.1.3,a and the Cox regression analyses were carried out using R version 2.10.1.b

      Results

      Table 2 gives the distribution of the baseline covariates according to the state occupied at the time of enrollment to home care and overall for all MSK patients. Among these, 74.7% were women, and 72.4% were 75 years or older. Almost 72% of patients had a baseline ADL score of 0 (indicating independence in toileting, locomotion, dressing, and eating), and 63.9% had not had a prior fall in the past 3 months. Only 18.3% of patients were receiving PT or OT at the time of admission. The mean score ± SD on the Charlson Crosswalk Comorbidity Index was 1.554±1.41 (again, note that we did not assign points for age, hence a lower comorbidity score than might be expected).
      Table 2Distribution of baseline covariates at time of entering into home care during first admission
      CovariateDomainInitial StateOverall (N=99,764)
      State 1 (n=4553)State 2 (n=66,762)State 3 (n=28,449)
      SexMen1310 (28.8)15,189 (22.8)8704 (30.6)25,203 (25.3)
      Women3243 (71.2)51,573 (77.2)19,745 (69.4)74,561 (74.7)
      Age group (y)Age <651056 (23.2)7583 (11.4)2955 (10.4)11,594 (11.6)
      65≤ Age <75906 (19.9)10,675 (16.0)4385 (15.4)15,966 (16.0)
      75≤ Age <851798 (39.5)28,443 (42.6)11437 (40.2)41,678 (41.8)
      Age ≥85793 (17.4)20,061 (30.0)9672 (34.0)30,526 (30.6)
      Baseline ADL ScaleScale = 04542 (99.8)66,419 (99.5)570 (2.0)71,531 (71.7)
      Scale ≥111 (0.2)343 (0.5)27,879 (98.0)28,233 (28.3)
      Falls frequency groupNo fall3584 (78.7)44,880 (67.2)15,288 (53.7)63,752 (63.9)
      1 falls629 (13.8)13.448 (20.1)7100 (25.0)21,177 (21.2)
      ≥2 falls340 (7.5)8434 (12.6)6061 (21.3)14,835 (14.9)
      CHESSScale = 02379(52.3)20,919 (31.3)5719 (20.1)29,017 (29.1)
      Scale = 1–22057 (45.2)39,320 (58.9)17,637 (62.0)59,014 (59.2)
      Scale ≥3117 (2.6)6523 (9.8)5093 (17.9)11,733 (11.8)
      CPSScale = 03525 (77.4)42,157 (63.1)10,060 (35.4)55,742 (55.9)
      Scale = 1–21019 (22.4)23,039 (34.5)12,521 (44.0)36,579 (36.7)
      Scale ≥39 (0.2)1566 (2.3)5868 (20.6)7443 (7.5)
      DRSScale = 03362 (73.8)44,573 (66.8)16,109 (56.6)64,044 (64.2)
      Scale = 1–2773 (17.0)14,034 (21.0)7189 (25.3)21,996 (22.0)
      Scale = 3–5287 (6.3)5914 (8.9)3587 (12.6)9788 (9.8)
      Scale ≥6131 (2.9)2241 (3.4)1564 (5.5)3936 (3.9)
      No. of days per week going out of home (last 3d)≥1d4435 (97.4)59,147 (88.6)19,316 (67.9)82,898 (83.1)
      No day118 (2.6)7615 (11.4)9133 (32.1)16,866 (16.9)
      Hours of exercise in last 3d≥2h4228 (92.9)54,869 (82.2)17,259 (60.7)76,356 (76.5)
      <2h325 (7.1)11,893 (17.8)11,190 (39.3)23,408 (23.5)
      PT/OT statusNo4153 (91.2)55,430 (83.0)21,963 (77.2)81,546 (81.7)
      Yes400 (8.8)11,332 (17.0)6486 (22.8)18,218 (18.3)
      NOTE. Values are n (%). The n indicates the number of patients at first admission. Patients must have completed baseline covariates, and these patients must contribute to the analysis.
      Table 3 contains the effects of PT/OT on transitions based on fitting a time nonhomogeneous Markov model to the data. Specifically, it presents odds ratios (ORs) obtained from the multinomial regression models formed on the transition probabilities, 95% CIs, and P values for testing the null hypothesis of no effect of PT/OT. The covariates controlled for in these analyses included age, sex, baseline ADL score, falls history, CHESS, CPS, DRS, Charlson Crosswalk Comorbidity Index, and stamina as indicated by days going outdoors and hours of physical activity.
      Table 3Multistate transition analysis for PT/OT versus none
      Current StateNext State
      State 1State 2State 3State 4State 5State 6
      State 1NA1.03 (0.83–1.28), .81311.48 (0.93–2.37), .09641.57 (1.27–1.94), <.00011.18 (0.84–1.64), .33371.38 (0.72–2.65), .3384
      State 21.36 (1.14–1.61), .0005NA0.99 (0.94–1.05), .83781.65 (1.57–1.72), <.00011.04 (0.98–1.09), .17250.92 (0.83–1.01), .0934
      State 31.17 (0.75–1.83), .47591.17 (1.10–1.26), <.0001NA1.32 (1.22–1.42), <.00010.74 (0.70–0.79), <.00010.81 (0.74–0.89), <.0001
      NOTE. Values are OR (95% CI), P.
      Abbreviation: NA, not applicable.
      The ORs in table 3 associated with individuals who were in state 3 (who needed assistance in eating, locomotion, toileting, or dressing) reveal that PT/OT interventions were associated with benefits with each outcome: increased odds of functional improvement to state 2 by the next assessment (OR=1.17; 95% CI, 1.10–1.26; P<.0001), reduced odds of a discharge to hospital or long-term care (OR=.74; 95% CI, .70–.79; P<.0001), increased odds of a discharge from home care services with a completed service plan or to a different community service (OR=1.32; 95% CI, 1.22–1.42; P<.0001), and reduced odds of death (OR=.81; 95% CI, .74–.89; P<.0001).
      For patients in state 2, PT/OT significantly increased the odds of functional improvement, reflected by a state 2 to state 1 transition (OR=1.36; 95% CI, 1.14–1.61; P=.0005), a strong and significant effect of PT/OT on a completion of home care with service plan complete (state 4) from state 2 (OR=1.65; 95% CI, 1.57–1.72; P<.0001). There was a suggestion of a protective effect for dying (OR=.92; 95% CI, .83–1.01; P=.0934), but OR=1.0 was not significant. There was no relationship observed between PT/OT services and institutionalization to either long-term care or the hospital.
      For patients in state 1, there was also a highly significant effect of PT/OT on the odds of a transitioning from state 1 to 4 (discharge from home care service with service plan complete: OR=1.57; 95% CI, 1.27–1.94; P<.0001). The relationship observed between PT/OT services and institutionalization or death was not significant, and there was no chance for improvement in functional state because patients were already considered independent in IADL and ADL.
      Figure 2 contains plots of the probabilities of the eventual outcome of discharge to state 4 (left panel), state 5 (middle panel), and state 6 (right panel) according to the state at admission to home care, by the time from admission to home care. As one might expect, patients in state 1 at the time of admission have a lower risk of being discharged to a hospital or to long-term care (state 5), and a higher probability of discharge from home care with a completed service plan or discharge to a different community service (state 4), and a lower risk of their home care service being terminated because of death (state 6).
      Figure thumbnail gr2
      Fig 2Plots of the probabilities of the eventual outcome of discharge to state 4 (left panel), state 5 (middle panel), and state 6 (right panel) according to the state at admission to home care, by the time from admission to home care. Abbreviations: ADL-H, ADL Hierarchy Scale; IADL-C, IADL Capacity Scale; LTC, long-term care.
      Table 4 reports the results of fitting Cox regression models in a competing risk framework.
      • Crowder M.J.
      Classical competing risks.
      Here we find a significant relationship between functional status (belonging to state 1, 2, or 3), along with age, sex, baseline ADL, falls status, CHESS, CPS, DRS, Charlson Crosswalk Comorbidity Index, and stamina (30d), and PT/OT utilization for transitions to both states 4 and 5. PT/OT in particular reduces the risk of discharge to a hospital or long-term care (state 5: HR=.926; 95% CI, .897–.956; P<.0001) and improves the probability of discharge from home care with services complete (state 4: HR=1.498; 95% CI, 1.447–1.550; P<.0001). PT/OT services are also associated with a significant reduction in the risk of death (state 6: HR=.905; 95% CI, .851–.964; P=.0017).
      Table 4Cox regression model
      CovariateState 4State 5State 6
      RR95% CIPGlobal, PRR95% CIPGlobal, PRR95% CIPGlobal, P
      ADL state: 2 vs 10.4690.444–0.495<.0001<.00011.1781.076–1.290.0004< .00011.2130.996–1.477.0546<.0001
      ADL state: 3 vs 10.3820.352–0.415<.00013.0120.822–3.409<.00013.4702.830–4.255<.0001
      65≤ Age <75 vs age <650.7460.712–0.782<.0001<.00011.2431.179–1.310<.0001< .00011.1601.049–1.282.0037<.0001
      75≤ Age <85 vs age <650.5810.558–0.605<.00011.4931.425–1.563<.00011.2091.106–1.322<.0001
      85≤ Age vs age <650.4670.446–0.489<.00011.7411.660–1.825<.00011.8532.693–2.028<.0001
      Sex: female vs male0.8330.806–0.861<.00010.8820.858–0.906<.00010.6410.610–0.673<.0001
      ADL score: ≥1 vs 00.9320.873–0.994.03330.5840.563–0.605<.00010.6700.624–0.718<.0001
      Falls: 1 vs 01.2220.180–1.266<.0001<.00011.1531.121–1.187<.0001<.00011.0280.970–1.088.3522.4892
      Falls ≥2 vs 01.0430.999–1.089.05721.2381.199–1.278<.00010.9830.921–1.050.6144
      CHESS: 1–2 vs 01.2501.209–1.293<.0001<.00011.2171.185–1.250<.0001<.00011.3711.296–1.451<.0001<.0001
      CHESS: ≥3 vs 01.2281.162–1.298<.00011.4031.348–1.461<.00012.1191.966–2.283<.0001
      CPS: 1–2 vs 00.8990.870–0.929<.0001< .00011.3661.332–1.401<.0001<.00010.9510.904–1.001.0537.0015
      CPS: ≥3 vs 00.7350.680–0.794<.00011.5281.464–1.594<.00011.0921.008–1.184.0320
      DRS: 1–2 vs 01.0350.999–1.073.0578.16711.0621.032–1.092<.0001<.00011.0080.953–1.065.7876.0023
      DRS: 3–5 vs 00.9980.949–1.050.95281.1251.083–1.169<.00010.9090.839–0.985.0203
      DRS: ≥6 vs 01.0520.977–1.133.18021.1061.044–1.173.00070.8220.724–0.933.0024
      Charlson Crosswalk Comorbidity Index0.9290.919–0.939<.00011.0511.042–1.059<.00011.2261.208–1.244<.0001
      No. of days per week going out of the home (last 30d): 0d vs ≥1d0.9360.895–0.978.00311.1731.138–1.209<.00011.4791.400–1.563<.0001
      Hours of exercise in last 30d (last 3d): <2h vs ≥2h0.9860.950–1.023.46410.9930.966–1.021.63101.2121.151–1.277<.0001
      PT/OT vs none1.4981.447–1.550<.00010.9260.897–0.956<.00010.9050.851–0.964.0017
      Abbreviation: RR, relative risk.

      Discussion

      This study demonstrated that long-stay home care patients have better outcomes if they receive services from physical and occupational therapists. Principally the findings demonstrate that patients who received PT/OT had increased odds of improving in ADL and IADL status regardless of their initial level of functioning. In addition to the functional improvements, PT and OT services were associated with system-level benefits, including reduced health system utilization such as reduced admissions to hospitals or long-term care. Persons in all 3 functional states were more likely to be discharged from home care services if they received 1 or both of the therapies. This can be considered a positive outcome because it represents lower costs for community home care, since personal support workers and other services are no longer necessary. Most importantly, persons with functional deficits were less likely to be sent to a hospital or long-term care. Lessening the need for institutionally based care represents positive outcomes for both the home care patients and the health system, including improved quality of life and decreased cost. By examining service utilization as well as functional improvements, this study has positioned PT and OT as key components of a cost-effective “aging at home” strategy.
      These findings are consistent with previous studies
      • Crotty M.
      • Whitehead C.
      • Miller M.
      • Gray S.
      Patient and caregiver outcomes 12 months after home-based therapy for hip fracture: a randomized controlled trial.
      • Kuisma R.
      A randomized, controlled comparison of home versus institutional rehabilitation of patients with hip fracture.
      • Stolee P.
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      • Glenny C.
      Inpatient versus home-based rehabilitation for older adults with musculoskeletal disorders: a systematic review.
      • Marchionni N.
      • Fattirolli F.
      • Fumagalli S.
      • et al.
      Improved exercise tolerance and quality of life with cardiac rehabilitation of older patients after myocardial infarction: results of a randomized, controlled trial.
      • Shepperd S.
      • Harwood D.
      • Jenkinson C.
      • Gray A.
      • Vessey M.
      • Morgan P.
      Randomised controlled trial comparing hospital at home care with inpatient hospital care. I: three month follow up of health outcomes.
      that argue that home-based rehabilitation can help to reduce overall costs to the health system by decreasing the need for institutional placement and replacing services such as in-hospital treatment with less expensive home visits without impeding the patient’s care. A recent systematic literature review
      • Stolee P.
      • Lim S.N.
      • Wilson L.
      • Glenny C.
      Inpatient versus home-based rehabilitation for older adults with musculoskeletal disorders: a systematic review.
      concluded that home-based rehabilitation may be an effective alternative for treating older patients with MSK conditions. The review found that older adults who received rehabilitation in the home had equal or higher gains than the inpatient group in function, cognition, and quality of life.
      • Stolee P.
      • Lim S.N.
      • Wilson L.
      • Glenny C.
      Inpatient versus home-based rehabilitation for older adults with musculoskeletal disorders: a systematic review.
      Our study had numerous strengths. All patients with 2 or more RAI-HC assessments and who had a primary or secondary MSK diagnosis were candidates for the study. There were a few exclusions (see table 1) because of missing information. Moreover, there were ample clinical and functional characteristics available within the RAI-HC to permit an informative comparison between persons who did and did not receive PT or OT services. The variables used in risk adjustment included individual items such as sex, age, falls, number of days going outside the home, and hours of physical activity within the past 3 days, as well as composite scales to reflect instability of condition, mood, and cognitive function. The analytic approach permitted a simultaneous comparison of competing risk including transition in functional status, death, and type of discharge while adjusting for the rich set of baseline covariates. Although we did not have a control group, we were able to assess the effect of PT/OT by comparing the rates of transitions between individuals with and without PT/OT, in the same functional state, with the same profile, as determined by the covariates we have controlled for.
      Some might argue that there is an endogeneity between those who are referred for PT/OT and those likely to improve. However Hirdes et al
      • Hirdes J.P.
      • Fries B.E.
      • Morris J.N.
      • et al.
      Home care quality indicators (HCQIs) based on the MDS–HC.
      found that 71.2% of older home care patients assessed as having rehabilitation potential did not receive any type of rehabilitation. Exploratory analyses by our group found substantial variation across home care regions in the proportion of patients who receive therapies, and failed to find clinical or functional characteristics that predicted referral to therapy. Given the regional variation, it is very likely that patients similar to those who received PT/OT did not receive therapy because of where they lived.
      The proportional hazards model illustrated that functional status is related to outcome. More independent persons were more quickly discharged from home care and took a longer time to be institutionalized or to die. There was a gradient for each outcome by level of function. Given this strong relationship with function, it is important to consider strategies and different models of care to improve function and prevent functional decline. This study supports a role for PT/OT within a broader strategy.
      Some might expect that long-term home care patients would not have the potential for improvement. Yet many chronic conditions are episodic, with fluctuations in symptoms and function. Persons may decline subsequent to inactivity caused by an injury or illness. Older adults are particularly vulnerable to skeletal muscle and functional change because of inactivity or bed rest.
      • Ikezoe T.
      • Mori N.
      • Nakamura M.
      • Ichihashi N.
      Atrophy of the lower limbs in elderly women: is it related to walking ability?.
      • English K.L.
      • Paddon-Jones D.
      Protecting muscle mass and function in older adults during bed rest.
      It is therefore important to have a good system of monitoring and signaling the need for a change in the service plan. In situations where personal support workers are regularly in the home, they have the potential to provide updates to case managers. Families should also be aware when there is a possible need for a “booster” program for patients with recent decline. Questions remain as to the amount of therapy needed to prevent decline and optimize outcomes, and how that may vary by patient characteristics. Alternate modes of delivery to provide yet more economical interventions should be examined. For example, tele-rehabilitation may both improve access and provide a less expensive option.

       Study limitations

      We recognize that this study has a number of limitations. The study population is limited to individuals receiving home care with MSK conditions. The study included long-stay patients with 2 or more RAI-HC assessments. Patients with shorter stays were not included. This limits the generalizability to all home care patients with MSK conditions but still permits comparison among long-stay patients—a group that is less often considered for referral to PT or OT. Overall, we may have underestimated the impact of PT/OT in home care by excluding postacute and short-term patients, since they may be the ones that will show the greatest amount of improvement. We also defined the outcomes for each state conservatively, using the items available in the RAI-HC instrument. Consideration of other variables in these state definitions may impact the findings.

      Conclusions

      In summary, it is important to seek cost-effective strategies to keep older adults well and at home. Rehabilitation professionals have the skills and competencies to set patients on the right course in their recovery, prevent further declines, and keep them safe and avoid falls. This study contributes to the evidence that PT/OT not only contribute by improving functional status, they also help avoid costlier services.

      Suppliers

      • a.
        SAS version 9.1.3; SAS Institute Inc, 100 SAS Campus Dr, Cary, NC 27513-2424.
      • b.
        R: a language and environment for statistical computing. Version 2.10.1. R-Development Core Team. The R Foundation for Statistical Computing, c/o Institute for Statistics and Mathematics, Wirtschaftsuniversität Wien, Augasse 2-6, 1090 Vienna, Austria. Available at: http://www.R-project.org.

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