Definition:

Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterized by recurrent, intrusive and disturbing thoughts as well as by repetitive stereotypic behaviors. OCD is a complex disorder and its pathogenesis is most likely influenced by both genetic and environmental factors. Although more than 140 candidate gene studies have been conducted, the findings have been inconclusive due to small sample size and few study replications. Many studies suggest that abnormal serotonergic neurotransmission is one of the most consistent biological findings in OCD. Studies have also reported dopaminergic abnormalities in the basal ganglia and nucleus accumbens, as well as altered glutamate transmission. First line treatments for this disorder are cognitive behavioral therapy (exposure and response prevention) and selective serotonin reuptake inhibitors (SSRIs). In recent years, one of the promising novel treatment strategies developed to improve the efficacy of treatment for patients with OCD is acceptance and commitment therapy (ACT). Recent studies have suggested that age of onset is an important factor in subtyping OCD. Early-onset OCD has been proposed to be associated with greater symptom severity, a higher prevalence of tic-related disorders, a more familial form of the condition, and a greater prevalence of psychiatry disorders in first-degree relatives as compared to late-onset OCD.