The impact of cognitive behavioral therapy for insomnia on cognitive performance and amyloid beta in older adults: A randomized controlled trial.

INTRODUCTION: Insomnia is associated with increased risk for Alzheimer's disease (AD). It is unknown how cognitive behavioral therapy for insomnia (CBT-I) impacts two hallmarks of AD progression, cognitive performance and beta-amyloid (Aβ) burden. METHODS: Cognitively normal older adults with symptoms of insomnia were randomized into CBT-I treatment (n = 100) or control (n = 100) groups. Cognitive performance was assessed at baseline, 6-weeks, and 1-year (1 year). Aβ burden was assessed in a subsample (n = 50). RESULTS: No differences were observed between groups in change in cognitive performance, including speed of information processing (mean difference, 0.017; 95% confidence interval [CI], -0.1036 to 0.1376; p = 0.78), executive function (-0.0881; 95% CI, -0.2945 to 0.1182; p = 0.40), and memory (0.4068; 95% CI, -2.3965 to 3.2101; p = 0.77). No group differences were observed in Aβ deposition. DISCUSSION: CBT-I did not improve cognitive performance or Aβ deposition by one year. Longer follow up is needed to understand the potential impact of CBT-I on AD risk. CLINICAL TRIAL REGISTRATION: The study was registered on clinicaltrials.gov (NCT03954210) on 5/17/2019.