29-04-2025
Lifestyle diseases raise heatstroke hospitalization risk by 2-5 times: Japan analysis
TOKYO -- People with lifestyle-related diseases risk hospitalization from heatstroke at a rate two to five times higher than those without such conditions, according to an analysis released this month by major Japan insurer Sumitomo Life Insurance Co.
The finding comes as the risk of heatstroke continues to rise in Japan due to extreme heat associated with global warming.
The company's "heatstroke white paper" found that heatstroke severity can differ by a person's health status. Sumitomo Life Insurance conducted the study with a firm handling big data from medical records of some 10 million people including health checkup data from health insurance associations. The relationship between heatstroke and health conditions identified in medical examinations was studied in the records for 2023 and 2024.
The analysis found that those taking medication to lower blood pressure faced a 3.5-fold higher risk, individuals using diabetes medication had a 4.9 times higher risk and those on medication for lipid disorders such as high cholesterol were 2.2 times likelier to be hospitalized for heatstroke than individuals not taking these medications.
Certain medications that increase fluid loss and lead to dehydration, as well as conditions like arterial sclerosis which worsen blood circulation and reduce the body's ability to dissipate heat, are thought to be among the major factors that heighten the risk of developing severe heatstroke.
Additionally, it was found that people were more likely to be hospitalized or require intravenous fluids due to heatstroke if they ate dinner just before bedtime, lacked proper sleep, smoked or had gained 10 kilograms or more from age 20. Getting too little sleep is thought to affect the body's ability to regulate its temperature, while smoking is another major cause of reduced heat dissipation efficiency by worsening blood circulation.
The summers of 2023 and 2024 were the hottest since the Japan Meteorological Agency began keeping records in 1898. In the Ministry of Health, Labor and Welfare's Vital Statistics, the number of deaths due to heatstroke in 2023 reached 1,651, amid a trend of temperatures hitting or exceeding 35 degrees Celsius in the daytime or remaining at or above 25 C overnight.
Sumitomo Life Insurance's report stated, "A history of hypertension, diabetes or dyslipidemia may increase the risk of heatstroke. Lifestyle modifications are also important in heatstroke prevention," while recommending people do moderate exercise, improve their health and gradually get used to the heat.
