A mortality prediction rule for non-elderly patients with community-acquired pneumonia

Masato Tashiro, Kiyohide Fushimi, Takahiro Takazono, Shintaro Kurihara, Taiga Miyazaki, Misuzu Tsukamoto, Katsunori Yanagihara, Hiroshi Mukae, Takayoshi Tashiro, Shigeru Kohno, Koichi Izumikawa

No mortality prediction rule is suited for non-elderly patients with community-acquired pneumonia. Therefore, we tried to create a mortality prediction rule that is simple and suitable for non-elderly patients with community-acquired pneumonia. Because of low mortality at young age, we used information from an administrative database that included A-DROP data. We analysed the rate and risk factors for in-hospital community-acquired pneumonia-associated death among non-elderly patients and created a mortality prediction rule based on those risk factors. We examined 49,370 hospitalisations for patients aged 18-64 years with community-acquired pneumonia. The 30-day fatality rate was 1.5 %. Using regression analysis, five risk factors were selected: patient requires help for feeding, the existence of malignancy, confusion, low blood pressure, and age 40-64 years. Each risk factor of our proposed mortality risk scoring system received one point. A total point score for each patient was obtained by summing the points. The negative likelihood ratio for the score 0 group was 0.01, and the positive likelihood ratio for the score ≥4 group was 19.9. The area under the curve of the risk score for non-elderly (0.86, 95 % confidence interval: 0.84-0.87) was higher than that of the A-DROP score (0.72, 95 % confidence interval: 0.70-0.74) (P < 0.0001). Our newly proposed mortality risk scoring system may be appropriate for predicting mortality in non-elderly patients with community-acquired pneumonia. It showed a possibility of a better prediction value than the A-DROP and is easy to use in various clinical settings.