Elderly heat stroke risk indirectly caused by COVID-19

Coronavirus disease 2019 (COVID-19) pandemic has direct and indirect health effects. This study analyzed the emergency transport data in Tottori Prefecture, which has the lowest number of infection cases in Japan, to evaluate the indirect impact of COVID-19 on heat stroke risk.

This study included 429 cases of emergency transported as heat stroke in Tottori Prefecture from April to October 2020. Moreover, the mean age, age structure, and the incidence situation were compared for 1,465 heat stroke transport cases from 2017 to 2019 (the control period before the COVID-19 pandemic). Descriptive statistics, one-way analysis of variance, and the χ² test were used in the analysis. The significance level was set at 5%.

The mean age ± standard deviation of emergency transport patients in 2020 was 66.2 ± 24.0 years, which was significantly higher than in 2017 (60.0 ± 27.9, p = 0.004), 2018 (57.4 ± 27.9, p < 0.001), and 2019 (57.6 ± 26.9, p < 0.001). The percentage of those <18 years old was 8.0% in 2020, which was lower than in other years (14.9%–18.0%). However, the percentage of those over 75 years old was 47.7%, which was higher than in other years (35.6%–44.2%, p < 0.001). Of the cases in 2020, 36.9% was picked up at home, which was higher than in other years (26.6%–29.3%). Moreover, 11.3% of the cases in 2020 were associated with exercise, which was lower than in other years (18.2%–20.4%, p < 0.001).

Thus, COVID-19 control measures, such as “stay-at-home” requests and the cancellation of events, may be reasons for some positive results. However, restricted outings may further increase elderly heat stroke risk for those who are typically more susceptible to heat stroke in the residence.