Objectives: To examine the effects of age and depressive symptom severity on changes in positive affect among older adults randomly assigned to a Mindfulness-Based Stress Reduction (MBSR) program or a Waitlist Control group. Drawing from the Motivational Theory of Life-Span Development, we hypothesized that lower levels of depressive symptom severity and older age would be associated with greater positive affect in response to the MBSR intervention.
Methods: Data were collected from a sample of community-dwelling English-speaking adults (n = 200) aged ≥ 65, randomly assigned to an eight-week MBSR program or a Waitlist Control group. Our main outcome variable was a five-item measure of positive affect, which was measured at study entry as well as eight weeks and six months later.
Results: At the six-month follow-up, we observed group by baseline depressive symptom severity (β = -.17, p = .02) and group by baseline depressive symptom severity by age (β = -.14, p = .05) interactions. Among MBSR participants, greater baseline depressive symptom severity was also associated with less improvement in positive affect at the six-month follow-up (β = -.30, p = .003). Findings were qualified by a significant depressive symptom severity by age interaction (β = -.25, p = .01), such that MBSR participants who were 70 and over with lower baseline depressive symptom severity having the greatest improvement in positive affect at the six-month follow-up.
Conclusion: MBSR improves positive affect for older adults with lower depressive symptom severity, perhaps because it capitalizes on naturalistic changes in control strategies.