Depressive illness and aggression in Belfast.

An inverse relation has been suggested between the incidence of depressive illness and the opportunity to externalize aggressive behaviour. The riot situation in Belfast in 1969-70 provided an opportunity to study this hypothesis. The incidences of depressive illness in the city and a neighbouring peaceful rural county were compared over a number of years. Data regarding age, sex, area of the city, and type of depression were obtained. The city was divided into areas and four of these were studied in detail. Similar data were obtained for persons showing aggressive behaviour.There was a significant decrease in depressive illness in Belfast in both sexes and all age groups. This was more pronounced in males but the decrease was confined to those in social groups IV and V. The decrease was more significant in riot areas. The suicide rate fell by almost 50% and there was a noticeable increase in the rates of homicide and crimes of violence. In contrast the rural county showed a sharp increase in male depressives.