Diagnostic delay in ADHD: Duration of untreated illness and its socio-demographic and clinical predictors in a sample of adult outpatients

Aim: To investigate the Duration of Untreated Illness (DUI) and its socio-demographic and clinical predictors in a sample of adult ADHD outpatients. Methods: The DUI of 150 adult outpatients with a confirmed diagnosis of DSM-IV ADHD was calculated. Non-parametric tests were used to evaluate differences in DUI among subgroups and to build a correlation matrix. Subsequently, a multiple linear regression model was performed. Results: The median DUI was 17 years (interquartile range [IQR] = 14). DUI was longer in employed patients, those with a family history of ADHD, those with a history of major depressive disorder and those who had predominantly inattentive ADHD in childhood. The current age, age at administration of the first proper treatment and education level were correlated with DUI. Current age (63.3% of total variance), family history of ADHD and the presence of a predominantly inattentive type in childhood (together, 2.6% of total variance) were all predictors of DUI. Conclusions: Information programmes for caregivers and training for health care professionals should be promoted to foster the early recognition of covert inattentive symptoms and shorten DUI.