IntroductionMajor depressive disorder (MDD) is a prevalent burdensome disease, which frequently remains untreated. The duration of untreated illness (DUI) is modifiable parameter and a valid predictor of outcome. Previous investigation in patients with MDD revealed a DUI of different years, while recent reports have documented a reduction of DUI across time, in patients with different psychiatric disorders.Objectives/aimsThe present study was aimed to investigate potential differences in terms of DUI and related variables in patients with MDD across time.MethodsAn overall sample of 188 patients with MDD was divided in two subgroups on the basis of their epoch of onset (onset before and after year 2000). DUI and other onset-related variables were assessed through a specific questionnaire and compared between the two subgroups.ResultsThe whole sample showed a mean DUI of approximately 4.5 years, with a lower value in patients with more recent onset compared to the other subgroup (27.1 ± 42.6 vs. 75.8 ± 105.2 months, P < .05). Moreover, patients with onset after 2000 reported higher rates of onset-related stressful events and lower ones for benzodiazepines prescription (65% vs. 81%; P = 0.02; 47% vs. 30%; P = 0.02).ConclusionsThe comparison of groups with different epochs of onset showed a significant reduction in terms of DUI and benzodiazepines prescription, and a higher rate of onset-related stressful events in patients with a more recent onset. Reported findings are of epidemiologic and clinical relevance in order to evaluate progress and developments in the diagnostic and therapeutic pathways of MDD in Italian and other countries.Disclosure of interestThe authors have not supplied their declaration of competing interest.