Vitamin D as potential antidepressant in outpatients with musculoskeletal pain

Objective: To determine the incidence of vitamin D deficiency, anxiety, and depression disorders in an outpatient population with musculoskeletal pain (MSP), and to evaluate the effects of correcting a vitamin D deficiency on MSP and psychological symptoms. Materials and methods: A total of 261 outpatients with MSP and 100 controls were involved. The Hospital Anxiety and Depression Scale (HADS) was used to assess psychological symptoms. Serum vitamin D was measured. Outpatients with vitamin D insufficiency and deficiency received oral vitamin D supplementation. Pain severity and psychological symptoms were evaluated before and after vitamin D supplementation plus dairy products. Results: Vitamin D deficiency was found in 88.7% of participants in the MSP group and 69% of controls. Clinical anxiety was reported by 38.3% of participants in the MSP group and 9% of controls, while clinical depression was reported by 31.8% of participants in the MSP group and 2% of controls. Multisite pain was significantly and positively associated with anxiety, depression, and pain severity, and was inversely associated with daily calcium intake. Anxiety was inversely associated with vitamin D level, daily calcium intake, and age. A similar pattern was observed for depression. MSP was the most significant independent predictor of anxiety (OR = 7.84) and depression (OR = 5.89). Relative to baseline, all measured outcome parameters significantly improved after vitamin D supplementation plus increased intake of dairy products. Conclusion: Low serum vitamin D is associated with MSP along with low calcium intake, depression, and anxiety. Supplementation with vitamin D improved MSP and associated disorders.