RESUMO
In individuals with type 2 diabetes (T2D), comorbid depression leads to increased health care costs and unsatisfactory treatment outcomes. Supporting healthy behaviors and self-efficacy might provide means to prevent depressive symptoms. We assessed the effects of motivational interviewing (MI) - based self-care promotion that specifically targets health behaviors, on depressive symptoms in adults with T2D. We followed PRISMA guidelines and searched Pubmed, Scopus, PsycINFO, Cinahl, and Cochrane Library to find randomized controlled trials (RCTs) published up to February 2023. Eligible RCTs had to target the T2D adult population, examine MI-based interventions that focus on multiple health behaviors, and measure depressive symptoms on a validated scale. Standardized mean differences (SMD) with 95% confidence intervals were calculated using a random-effects model. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of the evidence. After the screening, eleven studies with 2,682 individuals were eligible for the narrative synthesis. A meta-analysis of nine studies favored interventions with a pooled SMD of -0.19 (95% Cl = -0.34 to -0.05, p = 0.008, I2 = 52%). Due to the indirectness and imprecision of the evidence, we assessed the certainty of evidence based on GRADE as low. MI-based self-care promotion with a focus on health behaviors and implemented by a well MI-trained person had a preventive effect on depressive symptoms among adults with T2D. However, the certainty of evidence remained low. In future trials, the effect of MI-based self-care promotion on depression should be studied in clinically depressed populations.
RESUMO
Neurosteroid and immunological actions of vitamin D may regulate depression-linked physiology. Meta-analyses investigating the effect of vitamin D on depression have been inconsistent. This meta-analysis investigated the efficacy of vitamin D in reducing depressive symptoms among adults in randomized placebo-controlled trials (RCT). General and clinical populations, and studies of ill individuals with systemic diseases were included. Light therapy, co-supplementation (except calcium) and bipolar disorder were exclusionary. Databases Medline, PsycINFO, CINAHL and The Cochrane Library were searched to identify relevant articles in English published before April 2022. Cochrane risk-of-bias tool (RoB 2) and GRADE were used to appraise studies. Forty-one RCTs (n = 53,235) were included. Analyses based on random-effects models were performed with the Comprehensive Meta-analysis Software. Results for main outcome (n = 53,235) revealed a positive effect of vitamin D on depressive symptoms (Hedges' g = -0.317, 95% CI [-0.405, -0.230], p < 0.001, I2 = 88.16%; GRADE: very low certainty). RoB assessment was concerning in most studies. Notwithstanding high heterogeneity, vitamin D supplementation ≥ 2,000 IU/day appears to reduce depressive symptoms. Future research should investigate possible benefits of augmenting standard treatments with vitamin D in clinical depression. PROSPERO registration number: CRD42020149760. Funding: Finnish Medical Foundation, grant 4120 and Juho Vainio Foundation, grant 202100353.
