A study of serum brain-derived neurotrophic factor level in individuals with obsessive compulsive disorder and their first-degree relatives as compared to the healthy population

BACKGROUND: The nosological tradition in psychiatry defines diagnostic criteria for disorders based on expert consensus than objective biological markers reflecting underlying neurobiological correlates. Endophenotypes have been researched as heritable biological markers that can be quantified and defined to represent intermediate measures of a psychiatric illness. In obsessive-compulsive disorder (OCD), various putative biomarkers such as neuropsychological, neurophysiological, neuroradiological, brain-derived neurotrophic factor (BDNF), etc., have been explored. AIM: The study aimed to compare levels of serum BDNF in individuals with OCD and their unaffected first-degree relatives (FDR) with healthy controls (HC). METHODS: This cross-sectional study compared serum BDNF levels in medication-free/naive individuals with OCD (n = 30) to their FDR (n = 30) and age-sex matched HC (n = 30). Intergroup comparison was done using analysis of variance (ANOVA) and post-hoc Tukey’s test. Correlation analysis was conducted to find the relationship of sociodemographic and clinical correlates to serum BDNF as well as dimensional subtypes of OCD. RESULTS: No significant difference in BDNF levels was observed between OCD and HC (P = 0.13) but a significantly higher level was found in the FDR group compared to age-sex matched HC (P = 0.02). CONCLUSION: BDNF levels may have a complex interplay influencing the genetic inheritance and clinical manifestations of OCD. Further research is required before considering it a viable biomarker.