Silent Infections are not So Silent: The Emerging Role of Combined Infections, Inflammation, and Vitamin Levels in OCD.

ABSTRACT

Objective: Recent evidence highlights that different agents may trigger immune-mediated processes involved in the pathophysiology of different neuropsychiatric conditions. Given the limited information on obsessive-compulsive disorder (OCD), the present study aimed at assessing current/past infections and plasma levels of vitamin D, vitamin B12, folic acid, homocysteine and common peripheral inflammatory markers in a group of OCD outpatients. Method: The sample included 217 adult outpatients with an OCD diagnosis according to the DSM-5 criteria. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to assess the clinical phenotype and symptom severity. Laboratory blood tests measured levels of vitamin D, vitamin B12, folic acid, homocysteine, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), blood count and antibodies titers for cytomegalovirus (CMV), Epstein Barr virus (EBV), Toxoplasma gondii and antistreptolysin titer. Results: Sixty-one patients had a previous EBV infection, 46 were seropositive for CMV IgG, 24 showed positive antistreptolysin titer, 14 were seropositive for Toxoplasma gondii IgG, and four for CMV IgM. More than a half of patients showed vitamin D insufficiency. Compared to seronegative patients, patients with a past EBV infection displayed significantly higher scores on the Y-BOCS total score and compulsion subscale, and other symptoms. Vitamin D was negatively correlated with both the Y-BOCS total score and the subscales scores. Folic acid was negatively correlated with the Y-BOCS total and obsessions subscale score. Conclusions: The findings of our study show an association between Epstein-Barr infection and hypovitaminosis D and the overall severity and specific symptom patterns of OCD. The laboratory measures used in this study are useful, cheap and easy parameters that should be routinely assessed in patients with OCD. Further studies are needed to clarify their role in OCD pathophysiology and outcomes, as well as the potential therapeutic impact of vitamins and antibiotics/immunomodulatory agents in OCD and other psychiatric conditions.