Evaluation of interleukin-22 levels in obsessive-compulsive disorder patients in Bangladesh

Abstract

Obsessive-compulsive disorder (OCD) is a common neuropsychiatric disease with recurring obsessions and compulsions causing functional impairment. There is emerging literature indicating the association between immune dysregulation and cytokine profile in OCD. But there is no previous research about the Interleukin-22 (IL-22) amount present in the serum, which is pro-inflammatory as well as tissue-protective cytokine, in OCD patients. This case-control study was designed to investigate the serum level of IL-22 in OCD patients and its possible association with the disease. A total of 200 OCD patients and 176 controls with matched socio-demographic characteristics were enrolled in this study. OCD diagnosis was done using DSM-5 criteria, and Y-BOCS scale was utilized to find out the severity of the symptoms in patients. The serum level of IL-22 was estimated using ELISA method. It was found that the level of IL-22 in the serum of OCD patients (28.45 ± 0.54 pg/ml) was significantly lower when compared to healthy controls (32.22 ± 0.73 pg/ml), with p<0.001. However, considering the established knowledge concerning the involvement of IL-22 in the inflammation processes, it can be speculated that there is a certain problem in the regulatory mechanism of the immune response as well as tissue repair in patients. To the best of our knowledge, this appears to be the first study showing the IL-22 serum levels in patients with OCD in Bangladesh. Our findings indicate that the serum levels of IL-22 might be taken into account as a potential biomarker for OCD. Further research with larger sample sizes and broader cytokine panels is needed to confirm these findings and better understand the function and role of IL-22 in the disease progression in OCD.