A 3-year retrospective analysis of elderly patients with heat illness

Abstract

Background: Heat illness in elderly patients has frequently occurred. Because of the difficulties in diagnosis and treatment, it is necessary for us to understand the clinical characteristics of elderly patients with heat illness. Objective: This study presents the demographic, clinical, and laboratory data for elderly patients who presented to our emergency department with heat illness and compares elderly group and non-elderly group to find out characteristics of elderly patient. Methods: We retrospectively analyzed the data of the elderly heat illness patients who had been presented to the emergency department of Jinshan Hospital, Fudan University, between 1 July 2014 and 1 October 2016. Results: There were 64 patients in the study in total and 25 elderly patients (39.1%). The mean age of the elderly patients was 72.8 ± 6.7 years; 18 cases (72%) were male and 7 cases (28%) were female. There were 5 mild cases (20%) and 20 severe cases (80%) in the elderly, which included 1 with heat cramps (5%), 4 with heat exhaustion (20%), and 15 with heat stroke (75%). Lactate dehydrogenase and creatine kinase were significantly higher in the elderly than in the non-elderly (p < 0.0001; t-value = −3.915 and −5.134, respectively). The Acute Physiologic Assessment and Chronic Health Evaluation II score and Modified Early Warning System score were significantly higher in the elderly than in the non-elderly (p < 0.0001; t-value = −6.411 and −4.705, respectively). Age was positively correlated with the Acute Physiologic Assessment and Chronic Health Evaluation II score and Modified Early Warning System score (r 2 = 0.4939 and 0.3317, respectively; p value all <0.0001). The Acute Physiologic Assessment and Chronic Health Evaluation II score was positively correlated with lactate dehydrogenase and creatine kinase (r 2 = 0.4103 and 0.4520, respectively; p value all <0.0001). The Modified Early Warning System score was positively correlated with lactate dehydrogenase and creatine kinase (r 2 = 0.4759 and 0.5850, respectively; p value all <0.0001). There were 19 patients (76%) who improved and 6 patients (24%) who died in the elderly group. Conclusion: Chronic diseases and complications have increased rates in the elderly, who are also more likely to acquire severe heat illness, especially heat stroke. Lactate dehydrogenase and creatine kinase are positively correlated with Acute Physiologic Assessment and Chronic Health Evaluation II scores and Modified Early Warning System scores, which indicates that lactate dehydrogenase and creatine kinase could be good predictors of the severity of heat illness.