Preventing Cognitive Decline in Black Individuals With Mild Cognitive Impairment: A Randomized Clinical Trial.

Importance: Mild cognitive impairment (MCI) is a transition state between normal cognitive aging and dementia that increases the risk for progressive cognitive decline. Preventing cognitive decline is a public health priority. Objective: To determine whether behavioral activation prevents cognitive and functional decline over 2 years in black individuals with MCI. Design, Setting, and Participants: Single-center, single-masked, attention-controlled randomized clinical trial. Participants were enrolled from June 21, 2011, to October 3, 2014, and follow-up ended December 13, 2016. Community-based recruitment and treatment of black individuals older than 65 years with amnestic MCI. Volunteer sample of 1390 persons with memory complaints were screened. Overall, 536 individuals had baseline assessment, and 315 (58.8%) were ineligible, most often owing to normal cognition (205 of 315 [65%]) or dementia (59 of 315 [18.7%]); 221 fully eligible participants were randomized. Analyses were intention to treat. Interventions: Participants were randomized to behavioral activation, which aimed to increase cognitive, physical, and social activity (111 [50.2%]), or supportive therapy, an attention control treatment (110 [49.8%]). Main Outcomes and Measures: The prespecified primary outcome was a decline of 6 or more recalled words on the total recall score of the Hopkins Verbal Learning Test-Revised assessed at 6, 12, 18, and 24 months. The secondary outcome was functional decline. Results: Of 221 randomized participants (mean [SD] age, 75.8 [7.0] years, 175 women [79%]), 77 behavioral activation participants (69.4%) and 87 supportive therapy participants (79.1%) had 2-year outcome assessments. After baseline, behavioral activation participants engaged in significantly more cognitive activities than supportive therapy participants. The 2-year incidence of memory decline was 1.2% (95% CI, 0.2-6.4) for behavioral activation vs 9.3% (95% CI, 5.30-16.4) for supportive therapy (relative risk, 0.12; 95% CI, 0.02-0.74; P = .02). Behavioral activation was associated with stable everyday function, whereas supportive therapy was associated with decline (difference in slopes, 2.71; 95% CI, 0.12-5.30; P = .04). Rates of serious adverse events for behavioral activation and supportive therapy, respectively, were: falls (14 [13%] vs 28 [25%]), emergency department visits (24 [22%] vs 24 [22%]), hospitalizations (36 [32%] vs 31 [28%]), and deaths (7 [5%] vs 3 [4%]). Conclusions and Relevance: Behavioral activation prevented cognitive and functional decline, but this finding requires further investigation. Black individuals have almost twice the rate of dementia as white individuals; behavioral activation may reduce this health disparity. Trial Registration: ClinicalTrials.gov Identifier: NCT01299766.