Long-Term Impacts of Diurnal Temperature Range on Mortality and Cardiovascular Disease: A Nationwide Prospective Cohort Study

Abstract

Previous studies have documented the associations between short-term diurnal temperature range (DTR) exposure and cardiovascular disease (CVD) via time-series analyses. However, the long-term impacts of DTR through a population-based prospective cohort have not been elucidated thoroughly. This study aimed to quantify the longitudinal association of DTR exposure with all-cause mortality and CVD in a nationwide prospective cohort and, by extension, project future DTR changes across China under climate change. We included 22,702 adults (median age 56.1 years, 53.7% women) free of CVD at baseline from a nationwide cross-sectional study in China during 2012–2015, and examined three health outcomes during a follow-up survey in 2018–2019. We estimated the chronic DTR exposure as baseline annual mean daily maximum minus minimum temperature. The Cox proportional hazards regression was adopted to assess the multivariable-adjusted hazard ratio and its corresponding 95% confidence interval (95% CI). We employed 31 downscaled global climate models under two shared socioeconomic pathways for future projection. During the median follow-up period of ~5 years, 1096 subjects died due to all causes while 993 and 597 individuals developed fatal or nonfatal CVD and fatal or nonfatal stroke, respectively. The cumulative incidence rates of all-cause mortality, CVD, and stroke were 10.49, 9.45, and 5.64 per 1000 person-years, respectively. In the fully adjusted models, the risks for all-cause mortality, CVD, and stroke would increase by 13% (95% CI: 8–18%), 12% (95% CI: 7–18%), and 9% (95% CI: 2–16%) per 1 °C increment in DTR, respectively. Moreover, linear positive associations for the concentration–response curves between DTR and mortality and CVD were observed. We also found significantly greater DTR-related mortality risks among rural residents than their urban counterparts. The DTR changes featured a dipole pattern across China under a warming climate. The southern (northern) China would experience increased (decreased) DTR exposure by the end of 21st century. The present study indicates that chronic DTR exposure can exert long-term impacts on mortality and CVD risks, which may inform future public health policies on DTR-related susceptible population and regions.

All-cause mortality attributable to long-term changes in mean temperature and diurnal temperature variation in China: a nationwide quasi-experimental study

“…Our stratified analyses suggested that counties with lower levels of urbanization, a higher labor force ratio, and lower education levels seem to experience an increased risk of all-cause mortality linked to annual exposure to mean temperature and temperature variability. These findings align with previous findings [44,47,48]. For instance, Hu et al [47] explored the differences in temperature-mortality relationships between rural and urban regions of Zhejiang Province, China.…”

“…In alignment with previous findings, our observations revealed a strong association between the DTR and all-cause mortality [41][42][43]. A national study conducted in China, for instance, demonstrated that a 1 • C increment in the DTR elevated the risks of allcause, cardiovascular, and stroke mortality by 13% (95% CI: 8%, 18%), 12% (95% CI: 7%, 18%), and 9% (95% CI: 2%, 16%), respectively, after adjustment for potential confounders at the individual and regional levels [44].…”

Temperature variability increases the onset risk of ischemic stroke: A 10-year study in Tianjin, China

“…This present study was the first to assess the effect of TV on stroke onset by matching temperature variability to precise stroke onset timing. In line with previous regional and national studies, which demonstrated that high diurnal temperature range (DTR) was associated with hospital admission for ischemic stroke, and for every 1°C increase in DTR, the risk of stroke increased by 9% (2-16%) (16,17), we also found a positive correlation between temperature variability and stroke morbidity, with a 4.1% (1.9-6.3%) increase in ischemic stroke onset for every 1°C increase in TV 0-1 .…”

Augmented temperature fluctuation aggravates muscular atrophy through the gut microbiota

“…Increased DTR was reported to be a risk factor of many diseases based on epidemiological data 3 – 5 . Tang et al reported a significantly positive relationship between long-term DTR exposure and all-cause mortality, with a 13% higher risk of all-cause mortality based on a 1 °C increase in the DTR exposure 33 . In our study, we chose 10–25 °C for the mouse model, based on (1) the maximum mean DTR in all the cities included were 15.55 °C; (2) the mean daily maximum temperature is 21.6 °C, and the minimum is 11.9 °C.…”