Cardiovascular health, sleeping duration, and risk of mortality in current and former smokers

To investigate the associations of ideal cardiovascular health metrics (ICVHMs) with all-cause mortality among former and current smokers compared with never smokers.

A total of 378,147 participants [mean age (SD) years: 56.3 (8.1); 47.2 % men] were included from the UK Biobank cohort. The ICVHMs were combined Life's simple 7 from the American Heart Association and sleep duration time. The association was explored using COX regression models. During a median follow-up of 13.3 years, we documented 24,594 deaths. Compared with never smokers, among former smokers, the multivariable-adjusted hazard ratio (HR) for all-cause mortality was 1.82 (95%CI 1.71-1.92) for participants who had ≤2 ICVHMs and 1.03 (0.97-1.10) for participants who had ≥6 ICVHMs; among current smokers, the HRs for mortality were 2.74 (2.60-2.89) and 2.18 (1.78-2.67). The phenomenon was more pronounced among participants younger than 60 years [HR (95%CI), 1.82 (1.71-1.95) for ≤2 ICVHMs vs 1.04 (0.96-1.12) for ≥6 ICVHMs with age ≥60 years and 1.83 (1.62-2.06) vs 0.98 (0.88-1.11) with age <60 years among former smokers; 2.66 (2.49-2.85) vs 2.44 (1.84-3.24) with age ≥60 years and 2.85 (2.62-3.10) vs 1.96 (1.47-2.61) with age <60 years among current smokers]. In addition, the HR for mortality of each 1-number increment in ICVHMs was 0.87 (0.86-0.89) among former smokers and 0.91 (0.89-0.94) among current smokers.

Our findings indicated the importance of adherence to have more ICVHMs in the mortality risk among former smokers, and priority of smoking cessation in current smokers.

Studies have found that former smokers still have higher risks of lung cancer and all-cause mortality than never-smokers. The next question is whether the effects of previous or current smoking could be ameliorated by eight ideal cardiovascular health metrics (ICVHMs). We aim to explore whether ICVHMs may counteract the risk of all-cause mortality among former and current smokers. The results showed that only former smokers with ≥6 ICVHMs exhibited a comparable risk of all-cause mortality with never smokers. Furthermore, current smokers even having ≥6 ICVHMs still exhibited a higher risk of all-cause mortality compared with never smokers.