Self-inflicted burn injury is independently associated with increased mortality in a more economically developed country: A propensity score matching analysis

Self-inflicted burn accounts for considerable morbidity and mortality in more economically developed countries, and there is a substantial debate regarding the pathophysiological relevance between self-inflicted burns and unfavorable outcomes. To validate whether self-inflicted injury is an independent predictor of high mortality regardless of the severity of burn, they conducted a retrospective observational study using the Japan Trauma Data Bank, a nationwide database including over 200 major tertiary care centers. Among 2006 patients with burn who had arrived at collaborating centers between 2004 and 2016, they included patients aged ≥15 years, those who did not present with cardiopulmonary arrest upon arrival, and those who had ≥10 percent total body surface area burns. Patients with missing survival data or unknown mechanism of injury were excluded. In total, 1094 patients were eligible, of whom 222 (20.3 percent) had self-inflicted burns. The patients were divided into the self-inflicted and non-self-inflicted groups, and propensity score was calculated using the demographic information of the patients, injury variables, time from injury to hospital arrival, and other survival predictors. Via a propensity score matching, 98 pairs were selected, and the self-inflicted group had a higher mortality than the non-self-inflicted group (43.9 vs 28.6 percent, hazard ratio = 1.77; 95% confidence interval = 1.10-2.86; P =.02). Inverse probability weighting and multivariate logistic regression were performed as sensitivity analyses, and results validated that self-inflicted burn was independently associated with increased in-hospital mortality. Therefore, patients with self-inflicted burns should receive judicious management, regardless of burn injury severity.