Olfactory identification impairment in early-and late-onset obsessive-compulsive disorder.

Background: Early-onset obsessive-compulsive disorder (EOCD) is a comparatively severe subtype of obsessive-compulsive disorder (OCD). Olfactory dysfunction is a common symptom of OCD, but all previous studies have focused on late-onset OCD (LOCD).

Methods: The current study compared olfactory identification ability in EOCD patients and age-matched and sex-matched LOCD patients and healthy controls.