Effect of vitamin D supplementation on depression in elderly patients: A randomized clinical trial.

Treatment of depression in elderly population is a crucial issue. The effect of vitamin D supplementation on treatment of depression in older adults was investigated in this clinical trial. It was an 8-week, randomized clinical trial of vitamin D supplementation and placebo in the treatment of depression in 3 psychiatric clinics. The study sample included 78 older adults aged over 60 years with moderate to severe depression. Subjects were randomly allocated to receive 50,000 U vitamin D3 pearl weekly for 8 weeks or placebo (39 subjects in each group). Main outcome measures comprised Geriatric Depression Scale-15 (GDS-15) questionnaire and 25-hydroxyvitamin D3 [25(OH)D3]. The analysis utilized Mann Whitney U test, Wilcoxon signed ranks test, chi-square and multiple regression analysis. The mean baseline 25(OH)D3 concentration was 22.57 ± 6.2 ng/ml in vitamin D group and 21.2 ± 5.8 ng/ml in placebo group (p = 0.16). The Vitamin D increased to 43.48 ± 9.5 ng/ml in vitamin D and 25.9 ± 15.3 ng/ml in placebo group. The depression score decreased from 9.25 to 7.48 in vitamin D group (p = 0.0001), while there was a non-significant increase in depression score in placebo group. The multiple regression analysis showed that the vitamin D group and the score of depression before study were the variables that could explain 81.8% of depression score after intervention. The findings indicated that vitamin D supplementation can improve the depression score in persons aged 60 and over.