Effects of Vitamin D and Marine Omega-3 Fatty Acids Supplementation on Indicated and Selective Prevention of Depression in Older Adults: Results From the Clinical Center Sub-Cohort of the VITamin D and OmegA-3 TriaL (VITAL).

To test vitamin D and omega-3 fatty acids (omega-3s) for late-life depression prevention under the National Academy of Medicine framework for indicated (targeting subthreshold depression) and selective (targeting presence of high-risk factors) prevention. The VITamin D and OmegA-3 TriaL (VITAL) is a 2 × 2 factorial trial of vitamin D (2,000 IU/d) and/or omega-3s (1 g/d) for cardiovascular and cancer prevention (enrollment: November 2011-March 2014; end date: December 31, 2017). In this targeted prevention study, we included 720 VITAL clinical sub-cohort participants who completed neurobehavioral assessments at baseline and 2 years (91.9% retention). High-risk factors were subthreshold or clinical anxiety, impaired activities of daily living, physical/functional limitation, medical comorbidity, cognitive impairment, caregiving burden, problem drinking, and low psychosocial support. Coprimary outcomes were incident major depressive disorder (MDD), adjudicated using (, Fourth Edition), and change in mood (Patient Health Questionnaire-9 [PHQ-9]). We used exact tests to determine treatment effects on MDD incidence and repeated-measures models to determine treatment effects on PHQ-9. A total of 11.1% had subthreshold depression, 60.8% had ≥ 1 high-risk factor, MDD incidence was 4.7% (5.1% among completers), and mean PHQ-9 score change was 0.02 points. Among those with subthreshold depression, the MDD risk ratio (95% confidence interval) was 0.36 (0.06 to 1.28) for vitamin D and 0.85 (0.25 to 2.92) for omega-3s, compared to placebo; results were also null among those with ≥ 1 high-risk factor (vitamin D vs placebo: 0.63 [0.25 to 1.53]; omega-3s vs placebo: 1.08 [0.46 to 2.71]). There were no significant differences in PHQ-9 score change comparing either supplement with placebo. Neither vitamin D nor omega-3s showed benefits for indicated and selective prevention of late-life depression; statistical power was limited. ClinicalTrials.gov identifier: NCT01696435.