epidemiology

Last reviewed 01/2018

  • the life-time risk for schizophrenia is 1%.

  • the annual incidence if 0.1-0.5 per 1000 of the population.

  • incidence is highest between the ages of 35 and 39 in both males and females.

  • the prevalance of schizophrenia in the population is 2.5-5.3 per 1000.

  • risk for first-degree relatives of also being affected by the disorder is 10%. The risk of children being affected is 40%. Concordance in monozygotic twins is 40 to 50%; in dizygotic twins the concordance is 10%.

  • there is an excess of winter births among people in whom schizophrenia develops (by about 8%). The significance and mechanism associated with this risk factor are unknown.

  • there is an increased prevalence of gestational and birth complications in patients who subsequently develop schizophrenia.