Longitudinal coupling of obsessive-compulsive symptoms with depressive and anxiety symptoms: A cross-domain latent...

Obsessive-compulsive (OC) symptoms frequently co-occur with depressive and anxiety symptoms, yet the covariation of these symptoms over time is understudied. In this study, 2364 young adults (18-30 years) from a public university in Singapore were followed across five waves over 2.5 years. Latent growth curve models were estimated for OC, depressive, and anxiety symptoms, and parallel-process models examined cross-domain coupling, with regression models testing the unique influence of growth factors on OC symptom change. Results showed significant longitudinal coupling, primarily as co-improvement with steeper declines in depressive/anxiety symptoms associated with steeper declines in OC symptoms. A small subset of the sample (n = 21) showed co-worsening of OC and depressive symptoms. Higher baseline depressive and anxiety symptoms predicted slower OC improvement, highlighting the adverse impact of co-occurring internalizing symptoms. Only depressive trajectory uniquely predicted OC change beyond anxiety symptoms, suggesting that depressive symptoms may be a key influence in OC symptom progression. OC symptoms showed the greatest stability over time relative to depressive and anxiety symptoms. Overall, linked changes support shared etiological processes and underscore the role of comorbidity in maintaining OC symptoms, while also suggesting potential benefits of targeting transdiagnostic mechanisms or depressive symptoms in interventions. Longitudinal research tracking subclinical OC symptoms in community samples can further inform early identification and intervention strategies for OCD.