Several studies show as a long duration of untreated illness (DUI) is associated with poor outcome in schizophrenic patients.

Purpose of the present study was to evaluate eventual differences in terms of DUI between the diagnostic subtypes in a sample of schizophrenics coming from different geographic areas.

One hundred twenty-five schizophrenic patients of the Psychiatric Clinic of Milan (n = 51) and Moscow (n = 74) were enrolled. SCID-I was administered to all patients and information about DUI were obtained consulting clinical charts, health system databases, and performing interviews with patients and their relatives. DUI was defined as the time between the onset of symptoms and the administration of first antipsychotic. One-way ANOVAs were performed to find eventual differences in terms of DUI between the diagnostic subtypes.

Italian patients showed a longer DUI (4.14 years ± 4.95) in comparison with the Russian ones (1.16 years ±1.43). DUI was found to be longer in paranoid schizophrenics (3.47 years ± 4.19) respect to catatonic ones (0.96 years ± 0.94) (F = 3.56, p = 0.016).

The results of the present study show as the different schizophrenic subtypes can have a different DUI perhaps for the dissimilar clinical severity and social functioning. Studies with larger samples are warranted to confirm the data of the present study.