Sparsity of burn centers and prolonged length of hospital stay: A nationwide study.

Abstract

The optimal distribution of burn centers remains unclear. We aimed to determine the appropriate number of burn centers per population (density) and examined a nationwide registry with the hypothesis that low-density burn centers would be associated with unfavorable outcomes. A retrospective study was conducted using the Japanese Society of Burn Injury registry (2011-2021). Burn center density was defined as the number of burn centers per one million population in each prefecture, and centers were trisected on the basis of density. Hospital-free days until day 30 were compared between patients at high-, middle-, and low-density centers. Inverse probability weighting was conducted to adjust baseline characteristics, including age, burn mechanism, and burn severity. We included 6764, 6209, and 2200 patients at high-, middle-, and low-density burn centers, respectively. After adjusting for patient demographics and burn severity, patients at high- and middle-density centers (≥0.4 centers per one million population) had longer hospital-free days compared with those at low-density centers (11 [0-23] vs 11 [0-23] vs 8 [0-22] days; p < 0.001). Low burn center density (<0.4 centers per one million population) was associated with longer hospital stay, whereas no higher limit was determined.