A novel early risk assessment tool for detecting clinical outcomes in patients with heat-related illness (J-ERATO score): Development and validation in independent cohorts in Japan

Kei Hayashida, Yutaka Kondo, Toru Hifumi, Junya Shimazaki, Yasutaka Oda, Shinichiro Shiraishi, Tatsuma Fukuda, Junichi Sasaki, Keiki Shimizu

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Background We sought to develop a novel risk assessment tool to predict the clinical outcomes after heat-related illness. Methods Prospective, multicenter observational study. Patients who transferred to emergency hospitals in Japan with heat-related illness were registered. The sample was divided into two parts: 60% to construct the score and 40% to validate it. A binary logistic regression model was used to predict hospital admission as a primary outcome. The resulting model was transformed into a scoring system. Results A total of 3,001 eligible patients were analyzed. There was no difference in variables between development and validation cohorts. Based on the result of a logistic regression model in the development phase (n = 1,805), the J-ERATO score was defined as the sum of the six binary components in the prehospital setting (respiratory rate22 /min, Glasgow coma scale<15, systolic blood pressure100 mmHg, heart rate100 bpm, body temperature38C, and age65 y), for a total score ranging from 0 to 6. In the validation phase (n = 1,196), the score had excellent discrimination (C-statistic 0.84; 95% CI 0.79–0.89, p<0.0001) and calibration (P>0.2 by Hosmer-Lemeshow test). The observed proportion of hospital admission increased with increasing J-ERATO score (score = 0, 5.0%; score = 1, 15.0%; score = 2, 24.6%; score = 3, 38.6%; score = 4, 68.0%; score = 5, 85.2%; score = 6, 96.4%). Multivariate analyses showed that the J-ERATO score was an independent positive predictor of hospital admission (adjusted OR, 2.43; 95% CI, 2.06–2.87; P<0.001), intensive care unit (ICU) admission (3.73; 2.95–4.72; P<0.001) and in-hospital mortality (1.65; 1.18–2.32; P = 0.004). Conclusions The J-ERATO score is simply assessed and can facilitate the identification of patients with higher risk of heat-related hospitalization. This scoring system is also significantly associated with the higher likelihood of ICU admission and in-hospital mortality after heat-related hospitalization.

Original languageEnglish
Article numbere0197032
JournalPLoS One
Issue number5
Publication statusPublished - 2018 May 1


ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

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