Nighttime and day-night compound heatwaves linked to faster biological ageing in Chinese adults aged 45+
In a Chinese national cohort of adults aged 45+, longer exposure to nighttime and day-night compound heatwaves was associated with greater biological age acceleration, more strongly than daytime heatwaves. These are associations, not proof of cause. [1]
Automatic summary · not editorially reviewed
The key findings
Biological age was estimated from 11 clinical biomarkers at baseline (2011) and follow-up (2015). [1]
The study used parallel cross-sectional (n = 8223) and longitudinal (n = 5047) designs. [1]
Nighttime heatwaves showed the largest current-year biological age acceleration estimates in both analyses. [1]
The source at a glance
- Study type / format
- National cohort study with parallel cross-sectional and longitudinal analyses (abstract).
- Population / context
- Adults aged 45 and older from 125 prefectural cities across China; 8223 in the cross-sectional and 5047 in the longitudinal analysis.
- Summary based on
- Study abstract
- Original publication
- October 16, 2026
Heatwave subtypes and biological ageing in Chinese adults 45+
The researchers asked whether different kinds of heatwaves relate differently to biological ageing. They studied a national cohort of adults aged 45 and older from 125 prefectural cities in China. Biological age was estimated from 11 clinical biomarkers using the Klemera-Doubal method, measured at baseline in 2011 and at follow-up in 2015. Heatwaves were split into daytime, nighttime and day-night compound subtypes, based on daily maximum and minimum temperatures at several thresholds and durations.
Supporting source [1]
Cross-sectional and longitudinal analyses of heatwave exposure days
Two parallel designs were used: a cross-sectional analysis with 8223 participants and a longitudinal analysis with 5047. The researchers estimated how biological age acceleration changed per one additional day of cumulative heatwave exposure, using linear mixed-effects models. Subgroup and sensitivity analyses checked whether results held across different populations and heatwave definitions.
Supporting source [1]
Nighttime heat showed the largest biological age acceleration estimates
Longer heatwave exposure was consistently associated with greater biological age acceleration in both analyses. Under one definition (95th percentile, 3 days), nighttime heatwaves showed the largest current-year estimates: 0.0206 years in the cross-sectional and 0.0147 years in the longitudinal analysis. Day-night compound heatwaves were also positively associated and showed more persistent associations across extended exposure windows. Daytime heatwaves showed weaker, less consistent associations. Associations were stronger among women and urban residents. These are associations, not causes; the abstract does not report full-text details.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. The abstract reports associations, not causes. Details on confounder adjustment, exposure modelling and follow-up are not given in the abstract.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Wang J, Liu Y, Lin Q, Yuan Y, Zhang Y. · europepmc.org · October 16, 2026