The purpose of the study is to determine the extent to which suicidal behavior and psychiatric disorder is found in the relatives of adolescents who complete suicide compared with those who attempt and nonpsychiatric community controls. The proposed study is designed to extend an existing study of adolescent suicide victims. The extension will allow for the examination of lifetime histories of suicidal behavior and psychiatric disorder in the biological parents and siblings as well as in the more distant relatives of the adolescents. The study will provide information on (1) the likely importance of genetic factors that bear on youth suicide; (2) familial predispositions to youth suicide which may aid in early identification and prevention; (3) the distinguishing features of youth suicide which has shown a selective increase in incidence. Each biological parent of the adolescent completer, attempter, and nonpsychiatric control will be administered a modified version of the SADS-L in order to ascertain his/her lifetime history of psychiatric disorder and suicidal behavior prior to the death of the proband. Parents will also be administered a modified family history interview through which a lifetime history of psychiatric symptoms in the parent's first and second degree relatives (the adolescent's second and third degree relatives; e.g. grandparents, uncles, cousins) will be elicited. In order to ascertain psychiatric histories in the siblings, those younger than 19 will be administered the KSADS-E and those 19 and older, the modified SADS-L. The adjusted (to take into account the relative's age and other confounding variables) rates of suicidal behavior and psychiatric disorder in the relatives of the three adolescent groups will be compared.
