BACKGROUND:
Obsessive-compulsive disorder (OCD) is a chronic mental health condition characterized by intrusive thoughts and repetitive behaviors. Anonymous digital peer support groups like r/OCD, which has 180,000+ visitors weekly, may connect users with support and resources but may also enable compulsive behaviors like disclosure and reassurance‑seeking. Identifying patterns of user activity on r/OCD may help elucidate its benefits and harms.

METHODS:
All posts and comments added to r/OCD between October 12 and December 12, 2025 were extracted using Reddit API. A Gaussian mixture model identified latent user profiles based on activity times of each user with >1 post and/or comment. Then, sentiment analyses were used to compare posts/comments from each user profile.

RESULTS:
2,282 posts and 29,894 comments were added by 4,138 users. A six-class model was selected using AIC and BIC. The three largest user classes commented but never posted; they primarily shared OCD experiences (n=1,372; 10.1% of all comments) or provided encouraging replies sporadically (n=1,261; 47.3%) or regularly (n=799; 9.4%). Two smaller classes primarily shared distressing OCD experiences regularly (n=19; 3.1% of all posts, 0.1% of all comments) or in bursts during crises (n=442; 36.9%, 13.5%). The most active class (n=245) exhibited a broad range of activity and was responsible for 59.9% of all posts and 19.5% of all comments.

CONCLUSIONS:
80% of active users only comment on the forum occasionally, engaging in supportive or neutral ways; however, clinicians should be aware 10% of users appear to visit r/OCD for crisis support, displaying potentially compulsive sporadic activity that may hinder recovery. Most forum contributions come from a highly active 6% of users sharing diverse content. Further linguistic analyses may clarify adaptive and maladaptive activity signatures.