Cold waves carry a 40% higher death risk for people with diabetes

Extreme weather is usually discussed as a heat problem, and the health toll of heatwaves on vulnerable groups is comparatively well documented. The effects of the opposite extreme — cold waves — have received far less attention, even though people living with diabetes are considered at particular risk from severe weather events. With cold snaps a regular feature of many climates, quantifying what they do to diabetes-related illness and death matters for individuals and health systems alike. This review set out to pool the available evidence and put a number on that risk.

The researchers conducted a meta-analysis following PRISMA guidelines, searching the PubMed, SCOPUS and Web of Science databases from inception up to August 2023. They looked for studies assessing diabetes-related morbidity and mortality risks associated with cold-wave exposure, and eight studies met the inclusion criteria. Because the underlying studies differed from one another in setting and design, the team used a random-effects model to account for heterogeneity when pooling the results into overall relative risks for death and illness.

Cold-wave exposure was associated with a 40% increase in diabetes-related mortality risk — a relative risk of 1.40, with a 95% confidence interval of 1.25 to 1.58. Morbidity was also elevated, with a relative risk of 1.27, but its confidence interval of 0.99 to 1.63 crossed the line of no effect, so that finding was not statistically significant. The authors also noted that risk varied across the included studies, which they suggest reflects environmental and healthcare disparities between settings.

Heat-related harm in diabetes is relatively well documented, and this analysis extends the extreme-weather picture to the cold end of the thermometer, where evidence had been thin. The mortality signal is clear and consistent in direction, but the morbidity finding remains uncertain, and the authors flag gaps in understanding how cold waves drive illness rather than death. They also call for further work on the socioeconomic factors behind the variation between studies, since the pooled figure hides real differences in how exposed and protected different populations are.

If you live with diabetes, or someone close to you does, this is a reason to treat cold snaps as a genuinely higher-risk period rather than a mere inconvenience. The pooled evidence links cold-wave exposure to substantially higher diabetes-related mortality, even though the picture for illness short of death is less certain. It is also a reminder that weather-related health risk is not only about summer heat, and that access to warmth and healthcare during cold spells may shape how much risk any individual actually faces.