The Effect of Vitamin D Supplementation on Primary Depression: A Meta-Analysis
Introduction
This meta-analysis examined the effect of vitamin D supplementation on primary depression, with a particular focus on how baseline 25-hydroxyvitamin D [25(OH)D] levels influence treatment outcomes. The study aimed to clarify conflicting results from previous meta-analyses by conducting more precise subgroup analyses based on baseline vitamin D status.
Background and Rationale
Depression as a Global Health Challenge
Depression is one of the top ten causes of disability worldwide, with incident cases increasing from 172 million in 1990 to 258 million in 2017—a 49.86% increase. The high prevalence affects quality of life and places significant burden on social economies, making effective treatment strategies crucial.