Joint association of air pollutants and lifestyles on early-/late-onset heart failure: a population-based prospective cohort study

BACKGROUND AND AIMS: The interaction between air pollutants and lifestyles on heart failure (HF) and its variation by age of HF onset remains unclear. We aim to assess the joint association of air pollutants and lifestyles with HF and examine whether it differs between early- and late-onset HF. METHODS: : A cohort of 233,341 UK Biobank participants (2006-2010 baseline, followed up until 2023) was analyzed. Air pollution (NO2, NOx, PM10, PM2.5, PM2.5-10) and lifestyle (physical activity, smoking, sleep, diet, drinking, BMI) scores were computed, where higher scores indicated exposure to heavier air pollution or more unhealthy lifestyles. Cox models evaluated their associations with HF risk, and interactions were tested multiplicatively and additively. RESULTS: : High air pollution (scores in top tertile) and unfavourable lifestyle (scores up to 5∼6) were associated with higher HF risk independently. Joint-exposure analyses revealed that unfavourable lifestyle and high air pollution were jointly linked to HF, which appeared stronger for early-onset HF [relative excess risk due to interaction: 0.44 (95%CI:0.14∼0.74) for all HF, 1.33 (95%CI:0.03∼2.62) for early-onset HF, 0.39 (95%CI:0.08∼0.70) for late-onset HF; p-value for the early-versus-late interaction contrast=0.08]. In turn, lifestyle differences [between unfavourable (5∼6) and favourable (0∼2)] were associated with larger HF incidence differences in high than low air pollution group, especially for early-onset HF [1.62-fold (95%CI:1.42∼1.84) for all HF, 3.35-fold (95%CI:1.76∼9.79) for early-onset HF, 1.52-fold (95%CI:1.33∼1.74) for late-onset HF]. CONCLUSIONS: : Air pollutants and lifestyles are jointly associated with HF risk, with young adults in air-polluted areas potentially gaining greater benefits from lifestyle differences.