Which Impairments Are Most Associated With High Mobility Performance in Older Adults? Implications for a Rehabilitation Prescription

Abstract 

Bean JF, Kiely DK, LaRose S, Leveille SG. Which impairments are most associated with high mobility performance in older adults? Implications for a rehabilitation prescription.

Objective

To test which rehabilitative impairments are associated with higher mobility performance among community-dwelling, mobility-limited older adults.

Design

Cross-sectional analysis of baseline data from participants within a randomized controlled trial.

Setting

Outpatient rehabilitation research center.

Participants

Community-dwelling older adults (N=138; mean age, 75.4y) with mobility limitations as defined by the Short Physical Performance Battery (SPPB).

Interventions

Not applicable.

Main Outcome Measures

Balance measured via the Berg Balance Scale, leg strength, leg velocity, submaximal aerobic capacity, body mass index (BMI), and mobility performance as measured by the SPPB.

Results

Each of the 5 physiologic attributes (unipedal balance, leg strength, leg velocity, submaximal aerobic capacity, BMI) was categorized into tertiles by using lower values as reference for impairment status. Within an adjusted model, measures associated with higher SPPB performance (>9) included a BBS score greater than or equal to 54 (odds ratio [OR]=4.54; 95% confidence interval [CI], 1.11–18.60), leg strength greater than or equal to 21.5N/kg (OR=30.35; 95% CI, 5.48–168.09), leg velocity .0101 to .0129m·s⁻¹·kg⁻¹ (OR=5.31; 95% CI, 1.25–22.57), and leg velocity greater than or equal to .0130m·s⁻¹·kg⁻¹ (OR=22.86; 95% CI, 3.88–134.75).

Conclusions

Our investigation highlights the importance of rehabilitative impairments in leg strength, leg velocity, and balance as being associated with mobility status as measured by the SPPB. In our sample of participants within an exercise trial, submaximal aerobic capacity and BMI status were not associated with mobility performance. These findings suggest that the augmentation of not only leg strength and balance but also leg velocity may be important in the rehabilitative care of mobility-limited older adults.

Key Words: Aged, Strength, Velocity, Balance, Rehabilitation, Task performance and analysis

List of Abbreviations: BBS, Berg Balance Scale, BMI, body mass index, CI, confidence interval, DLP40, double leg press power measured at 40%, ETT, exercise tolerance test, OR, odds ratio, RM, repetitions maximum, SPPB, Short Physical Performance Battery