Vitamin D Levels in Lebanese Patients with Schizophrenia: A Case-Control Study

Objectives: To compare the vitamin D status in schizophrenics to that of healthy controls; secondary objectives were to assess the correlation between severe vitamin D deficiency and the severity of schizophrenia symptoms and to evaluate the potential factors influencing this status. Methods: A case-control study, conducted between March and July 2016, recruited 100 patients with schizophrenia and 100 controls with no known psychiatric disorders and matched for age and sex. Results: Schizophrenic patients had a more severe vitamin D deficiency compared to healthy controls (9% vs. 3%). Vitamin D insufficiency was found in 28% of schizophrenic patients compared to 37% in healthy controls (p=0.053). BCRS and MRSS scales were significantly associated with a more severe vitamin D deficiency (p=0.006). We couldn't detect any association between the total PANSS score and its three subscales with vitamin D deficiency (p>0.05). Sun exposure, intermediate and high socioeconomic levels would significantly increase the odds of having an increased level of vitamin D as compared to low socioeconomic level (OR=1.046, OR=141.919 and OR=132.110) respectively. Higher MRSS scores would significantly increase the odds of having a more severe vitamin D deficiency by 15.2% (OR=0.848, CI 0.731 - 0.984, p=0.029). Conclusion: Vitamin D insufficiency is prevalent in patients with schizophrenia. Further work is needed to answer the question of causality. Is vitamin D deficiency the result or the cause of schizophrenia? Future cohort studies may investigate the association with longer follow-up. Spreading awareness among health care professionals for routine serum vitamin D testing, along with patient education, are necessary to avoid this problem.