Article Text
Abstract
Objectives To determine the predicting effect on youth suicide of prior episodes of injuries of various intent (ie, inter-personal and self-directed violence, unintentional and undetermined intent) and the extent to which any association is influenced by family socioeconomic status.
Methods A nationwide register-based cohort study was conducted covering all Swedish subjects born between January 1977 and December 1991 (N=1 616 342, male/female ratio=105). The cohort subjects were followed up from January 1998 to December 2003, when aged 726 years. Poisson regression and the likelihood ratio test (CI 95%) were used to assess the age-adjusted effect of hospitalisation for injuries of various intents on youth suicide and its effect once adjusted for family sociodemographic and social circumstances.
Results Each set of exposures independently and significantly predicted suicide mortality. Being hospitalised for self-inflicted injuries or injuries of undetermined intent was associated with a risk of suicide 36–47 times that of subjects never hospitalised in the period under study (95% CI 28.36 to 45.58 and CI 26.67 to 83.87 for self-inflicted injuries and for events of undetermined intent, respectively; overall p<0.01). Similarly, previous events of unintentional injury remarkably increased the risk of suicide (RR 3.08; 95% CI 2.26 to 4.19). These effects were solid and not substantially altered after adjustment for family demographic and socioeconomic circumstances.
Conclusion Youth suicide is predictable not only by prior suicide attempts but even by prior exposure to injurious assaults and unintentional injuries leading to hospitalisation, regardless of family socioeconomic status.