Psychiatric illness among adults adopted as infants.

In an epidemiological study of 2,323 adopted adults, the registrations about sick-leave, diagnoses and hospitalization (F-cards) from the National Health Insurance were studied. There was a significantly higher frequency of psychiatric illness among the adoptees compared with non-adopted controls. A classification into different diagnostic groups from the records of psychiatric hospitals showed an over-representation due to alcohol and drug abuse and personality disorders in both male and female adoptee groups compared with non-adopted controls. There was also an over-representation in the male adoptee group due to neuroses.