Objective: We evaluated the effects of three cognitive training interventions on depressive symptoms at 1 and 5 years.
Methods: Advanced Cognitive Training for Independent and Vital Elderly is a multisite randomized controlled trial (age >or= 65 years), with four groups (memory, reasoning, speed-of-processing, and no-contact control). Complete data were available for 2,014 (72%) and 1,516 (54%) of 2,802 participants at 1 and 5 years. Separate propensity score models adjusted for potential attrition bias. Clinically important increases in depressive symptoms were defined as: (a) Center for Epidemiological Studies-Depression scale (CES-D)-12 score increases >or=0.5 SD and (b) CES-D-12 score increases >or=1.0 SD. Multivariable logistic regression was used.
Results: The speed-of-processing group (vs the no-contact control group) was 30% less likely to experience clinically important increases in depressive symptoms at 1-year (adjusted odds ratio [AOR] = 0.700, p = .012) and 5-year (AOR = 0.698, p = .023) posttraining for the >or=0.5 SD threshold. Similar results (AOR = .669 with p = .039 at 1 year; AOR = 0.651 with p = .059 at 5 years) were obtained for the >or=1.0 SD threshold. No differences were observed among the control, memory, or reasoning groups at either time period or at either threshold.
Conclusion: The speed-of-processing intervention reduced the risk of clinically important increases in depressive symptoms at 1- and 5-years postbaseline.