Background/Objectives
Information about the safety of physical activity (PA) programs in older adults with mobility limitations is critically important to inform clinicians and others responsible for their clinical management. We conducted a safety analysis of study hospitalization data and determined whether the intervention was differentially associated with categories of hospitalizations or subgroups of participants.
Design
Multicenter RCT. Participants randomized to a PA or health education (HE) program for an average of 2.6 years.
Setting
8 field centers.
Participants
1,635 sedentary men and women aged 70-89 years with lower extremity physical limitations, but able to walk 400-m in ≤15 min.
Interventions
Structured, moderate-intensity PA (n = 818) at a center (2x/wk) and at home (3-4x/wk) that included aerobic, strength, balance, and flexibility training or HE (n = 817) of educational workshops and upper extremity stretching exercises.
Main Outcomes and Measures
All cause in-patient hospitalizations ascertained at six-month intervals.
Results
49.1% of PA and 44.4% of HE (risk difference=4.68%, 95%CI −0.18 to 9.54; HR=1.16, 95%CI 1.00 to 1.34) reported a total of 1458 hospitalizations. The intervention effect on incident hospitalization did not differ by race, sex, SPPB, age, and history of CVD/diabetes. PA was associated with an increase in the rates of hospitalization within the middle baseline gait speed category, compared to HE: <0.8m/s, HR[95%CI] 0.93[0.76-1.14]; 0.8–1.0m/s, 1.54[1.23-1.94]; >1.0m/s, 1.05[0.67-1.65]; interaction p=0.005).
Conclusion/Relevance
A PA program in older adults at risk for mobility disability did not lead to a differential risk of specific types of hospitalizations compared to a HE group, overall. Baseline gait speed may be a marker for risk of hospitalization during a PA intervention, as individuals with moderate baseline gait speed in the PA group had slightly higher rates of hospitalizations, compared to HE.