Preterm birth and psychiatric medication prescription in young adulthood: a Swedish national cohort study.

BACKGROUND: Recent studies suggest an increased risk of adverse mental health outcomes among young adults who were born preterm. These studies have been based mainly on hospital data, thus missing large numbers of mental health problems that do not require inpatient treatment. We used national outpatient and inpatient pharmacy data to evaluate whether individuals who were born preterm were more likely to be prescribed psychiatric medications during young adulthood than individuals who were born full term. METHODS: A national cohort of all infants born in Sweden from 1973 through 1979 [N = 635 933, including 28 799 who were born preterm (