Objective:
Older adults are the least active population group in the U.S. Low income and ethnically diverse communities have fewer physical activity (PA) related resources and facilities, which contributes to lower PA levels and disparities in cardiovascular (CVD) risk factors and disease outcomes. This study assessed the hypothesis that low income and diverse older adults participating in the multilevel Peer Empowerment Program 4 Physical Activity (PEP4PA) would increase moderate-to-vigorous PA (MVPA), improve blood pressure (BP), perceived quality of life (PQoL), and depressive symptoms to a greater extent than older adults receiving usual senior center programming.
Methods:
In a cluster-randomized controlled trial (RCT) in 12 senior centers, 476 older adults (mean age 71.4 years, 76% female, 60% low income, 38% minority) were assigned to a PA intervention (n=267) or control (n=209) condition. The peer-led intervention included individual self-monitoring and counseling, group walks and social support, and community advocacy to improve walking conditions. Outcomes included minutes of MVPA per day (7-day accelerometer), systolic and diastolic BP (automatic cuff), PQoL (PQoL-20) and depressive symptoms (CES-D 10) at baseline, 6, 12, 18 and 24 months. To account for multiple measurement days and clustering of participants within senior centers, mixed effects regression models with random effects estimated the intervention effects on all outcomes between groups over time. Models were adjusted for imbalanced baseline covariates. A three-way interaction term assessed whether intervention effects differed by income status.
Results:
Compared to the control group, intervention participants significantly increased MVPA from baseline at 6, 12, 18 and 24 months by 8, 11, 9 and 9 minutes/day respectively (p<0.001), with increases remaining statistically significant across the 2-year period. The intervention group significantly increased mean PQoL scores from 7.2 at baseline to 7.6 (p<0.001), 7.8 (p=0.008) and 7.7 (p<0.001) at 12, 18 and 24 months, compared to control participants. No significant effects were observed for BP or depressive symptoms. Low income participants decreased minutes of MVPA, compared to higher income participants, at 12 and 24 months (β=-7.9, p=0.008 and β=-10.8, p=0.001).
Conclusions:
The multilevel RCT achieved sustained increases in MVPA and QoL in a diverse cohort of older adults across 2 years of follow up. The peer-led, community-based intervention provides a sustainable model to improve health behaviors related to CVD in an at-risk and often difficult to reach aging population. Further exploration is needed to understand what components of the intervention may be modified to address the differential effects by income status.
Meeting the Challenges of Longitudinal Cluster-Based Trials in Schools: Lessons From the Chicago Trial of Positive Action
