Mutual Associations of Healthy Behaviours and Socioeconomic Status with Respiratory Diseases Mortality: A Large Prospective Cohort Study

Little cohort evidence is available on the effect of healthy behaviours and socioeconomic status (SES) on respiratory disease mortality. We included 372,845 participants from a UK biobank (2006–2021). SES was derived by latent class analysis. A healthy behaviours index was constructed. Participants were categorized into nine groups on the basis of combinations of them. The Cox proportional hazards model was used. There were 1447 deaths from respiratory diseases during 12.47 median follow-up years. The hazard ratios (HRs, 95% CIs) for the low SES (vs. high SES) and the four or five healthy behaviours (vs. no or one healthy behaviour) were 4.48 (3.45, 5.82) and 0.44 (0.36, 0.55), respectively. Participants with both low SES and no or one healthy behaviour had a higher risk of respiratory disease mortality (aHR = 8.32; 95% CI: 4.23, 16.35) compared with those in both high SES and four or five healthy behaviours groups. The joint associations were stronger in men than in women, and in younger than older adults. Low SES and less healthy behaviours were both associated with an increased risk of respiratory disease mortality, which augmented when both presented together, especially for young man.