Vitamin D and clinical symptoms in First Episode Psychosis (FEP): A prospective cohort study.

Background: There is a paucity of longitudinal research investigating vitamin D in people with early psychosis.

Method: Vitamin D levels were measured in 168 patients (64% (n = 108) male, mean age 29.3 (9.8) years) with first episode psychosis (FEP), along with measures of clinical state at baseline and at 12 months follow up. We assessed the a) cross sectional, and; b) longitudinal relationships between continuous and categorical 25-hydroxyvitamin D (25(OH)D) levels and clinical symptoms at first contact for psychosis and at 12 months.

Results: In FEP, 80% (n = 134) at baseline, and 76% at 12 months follow up, had suboptimal vitamin D levels (<20 ng/ml). Suboptimal levels of 25 (OH) D at baseline were not cross-sectionally associated with clinical symptoms. Higher vitamin D levels at baseline (n = 77) were significantly associated with better visual reproduction-immediate recall (β = 0.249, 95%CI = -0.012-0.871, p = 0.044). Higher baseline vitamin D levels were prospectively associated with lower total PANSS (β = -0.24, 95%CI = -0.47-0.01, p = 0.04) and PANSS negative symptom scores (β = -0.12, 95%CI = -0.23-0.01, p = 0.04) at 12 months.

Conclusion: We identified a prospective association between higher baseline serum Vitamin D levels and lower total psychotic symptoms and negative symptoms of psychosis at 12 months after first contact for psychosis. The results of this study require replication in larger prospective studies, and highlight the need for large randomised trials to assess the effect of vitamin D supplementation on symptoms of psychosis in FEP.