Double suicide and homicide-suicide in Switzerland.

Double suicide and homicide-suicide are infrequent and are different in psychopathology from that of a single suicide. However, precipitating factors for double suicide and homicide-suicide are similar to these found in single suicide. Depression, borderline disturbances, and narcissistic neuroses in combination with stressors such as physical illness, isolation, and social losses can lead to homicide-suicide. Epidemiological studies indicate that double suicide and homicide-suicide are influenced by ethnicity and cultural and social background. This study explores the situation in Switzerland between 1928-48 and 1971-1990.