Flooding exposure accelerated biological aging: a population-based study in the UK

Abstract

Background
Floods have been the most common type of disaster and are expected to increase in frequency and intensity due to climate change. Although there is growing evidence on the impacts of floods on human health, none has so far investigated the association between flooding exposure and biological aging acceleration. 
Methods
We collected data from 364,841 participants from the UK Biobank project. Flooding data before baseline were retrieved from the Dartmouth Flood Observatory and linked to each participant. A novel index termed the "flood index" was developed for this study, which incorporates both the duration of exposure to floods and the severity of each flood event. We calculated the two biological aging measures at baseline: PhenoAge and Klemera-Doubal method biological age (KDM-BA) and assessed their associations with flooding exposure using mixed-effects linear regression models. 
Results
We observed that participants exposed to higher levels of floods were more likely to have accelerated biological aging. The risks associated with flooding exposure could last for several years, with the highest cumulative effect observed over 0–4 years. In the fully adjusted model, per interquartile increase in flood index was associated with an increase of 0.24 years (95% CI: 0.14, 0.34) in PhenoAge acceleration and 0.14 years (95% CI: 0.07, 0.21) in KDM-BA acceleration over lag 0–4 years. The associations were consistent regardless of lifestyles, demographics, and socio-economic status.
Conclusions
Our findings suggest that exposure to floods may lead to accelerated biological aging. Our work provides the basis for further understanding of the flood-related health impacts and suggests that public-health policies and adaptation measures should be initiated in the short-, medium- and even long- terms after flooding.