Key clinical point: Vitamin D deficiency is associated with the risk of developing schizophrenia in adults.

Major finding: Patients with schizophrenia had significantly lower mean vitamin D concentrations vs. controls (weighted mean difference, −4.68 ng/mL; P less than .001). Overall prevalence of vitamin D deficiency (VDD) and vitamin D insufficiency (VDI) in patients with schizophrenia was 68% and 76%, respectively. VDD (odds ratio [OR], 2.09; P = .004) and VDI risk (OR, 2.43; P = .004) were higher in patients with schizophrenia vs. controls.

Study details: Meta-analysis of 36 studies including 12,528 participants.

Disclosures: No study sponsor was identified. The authors declared no conflicts of interest.

Commentary

“A body of evidence suggests that vitamin D has a role in the central nervous system as a neuroprotective and dopamine modulating steroid. Deficiency in vitamin D is highly prevalent and may be more common among individuals with wide variety of chronic health conditions including some psychiatric illnesses. This systematic literature review, which found that vitamin D deficiency is more common in samples with schizophrenia vs. controls. lends support to findings from other reports suggesting vitamin D deficiency could be an additional risk factor for schizophrenia. An important caveat is that schizophrenia is a highly heterogenous condition and factors that contribute to risk encompass genetic and environmental risk domains. Still, given that vitamin D insufficiency is potentially modifiable, additional and prospective research that more rigorously assesses vitamin D levels in response to cumulative risk burden needs to be conducted.”

Martha Sajatovic, MD

Professor of Psychiatry and of Neurology

Willard Brown Chair in Neurological Outcomes Research

Director, Neurological and Behavioral Outcomes Center, University Hospitals Cleveland Medical Center

Case Western Reserve University School of Medicine