Patterns of suicidal behaviour in a metro subway system - A study of 306 cases injured by the Munich subway, 1980-1999

Background: As a basis for preventive strategies to reduce subway suicides, an investigation was undertaken to determine if there was a distinct pattern of subway suicidal behaviour. Methods: Data were taken from the Municipal Munich Subway System case registry (southern Germany) for all suicidal incidents on the track: purposely inflicted; date, time and location of incident, sex of victim, outcome. The analysis covered a 20 year observation period between 1980 and 1999, for which the Munich Municipal Office for Statistics also provided data of all deaths due to suicides within the city area of Munich. Suicide mortality was classified by the International Classification of Diseases, Ninth revision (codes E950-E959). Results: A total of 306 incidents were documented with an annual mean of 16.5 cases. Case fatality was 66% (n=202). It was highest in winter and in higher aged groups. No significant time trend for incidences was observed. Median age of suicide attempters was 38 years. Most incidences (24.2%) were recorded for persons aged 20-29 years. The male: female ratio was 1.15 : 1. The peak time of day for incidences in women was during the late morning hours while significantly more men committed subway suicides during evening hours (p=0.001). No consistent seasonal variation was observed. Conclusions: In comparison to average suicide attempters, subjects committing subway suicides are markedly younger and they follow to a lesser extent established seasonal or circadian time patterns. More women are involved in subway suicides than would be expected. However, similarities to reports on behavioural patterns of subway suicides in other communities are striking.