0375 Predictors of Insomnia and Depression in a Randomized Controlled Insomnia Treatment Trial in the COVID-19 Pandemic

Abstract Introduction The COVID-19 Pandemic resulted in increases in insomnia risk factors, including elevated sleep reactivity, perceived stress, loneliness, and screen time. Here, we test whether these factors predicted worse subsequent insomnia and depression symptoms as part of a randomized controlled feasibility trial of a brief insomnia intervention early in the pandemic. Methods Forty-nine participants with acute pandemic-onset insomnia symptoms were randomized to receive telehealth Cognitive Behavioral Therapy for Insomnia (CBT-I) over five weeks or to a waitlist control. Participants completed baseline measures of sleep reactivity, perceived stress, loneliness, and screen time. Outcome measures included the Insomnia Severity Index and the Patient Health Questionnaire-9 (minus the sleep item) collected at 12 and 28 weeks. As described in the protocol paper, two likelihood ratio tests (one for insomnia and one for depression) were used to test the hypothesis that the risk factors collectively contribute to subsequent insomnia and depression. Specifically, for each outcome, likelihood ratio tests compared a linear mixed effect model containing the 4-baseline risk factor measures and treatment arm as predictors against a model containing only treatment arm. Considering our joint hypothesis test does not address the significance of individual risk factors, we tested whether each risk factor was predictive in isolation using post-hoc mixed effects models (one for each risk factor across insomnia and depression while still controlling for treatment arm). Benjamini-Hochberg adjustment for multiple comparisons was used across the 8 post-hoc models. Results Collectively, the insomnia risk factors did not predict subsequent insomnia or depression (p’s>0.25, marginal ΔR2’s< 0.518) above what would be predicted by receiving CBT-I or waitlist control. However, when considered in individual models, perceived stress and loneliness were significant predictors of both outcomes (b’s>0.22, adjusted-p’s< 0.012) above and beyond treatment arm. Screen time and sleep reactivity were not significant predictors of either outcome (b’s< 0.13, adjusted-p’s>0.149). Conclusion Although this study was conducted in a relatively small sample, these results suggest that increased loneliness and perceived stress may be associated with worse insomnia and depressive symptoms several months later. Thus, loneliness and perceived stress may represent early intervention targets during periods of acute stress and disruption, like the COVID-19 pandemic. Support (if any)