Time from waking to the first cigarette and mortality and incident cardiovascular disease.

Background: This study aimed to investigate the associations of time from waking to the first cigarette (TWFC) with all-cause mortality, cardiovascular disease (CVD) mortality and incident CVD among people smoking.

Methods: Data were from the UK Biobank, including 32 519 people smoking aged 40-70 years. TWFC was investigated using a touch-screen questionnaire. Outcomes included all-cause mortality and mortality from and incidence of CVD, ischemic heart disease (IHD) and stroke.

Results: Compared with participants reporting TWFC >120 min, those reporting TWFC between 61 and 120 min (HR, 1.30; 95% CI, 1.10-1.53), TWFC between 5 and 60 min (1.48, 1.30-1.70) and TWFC <5 min (1.65, 1.42-1.93) had a higher risk of all-cause mortality. Compared with participants reporting TWFC >120 min, those reporting TWFC between 5 and 60 min and TWFC <5 min had higher risks of CVD and IHD mortality and incident CVD and IHD, but those reporting TWFC between 61 and 120 min did not. The associations of TWFC with stroke mortality and incident stroke were not observed.

Conclusion: In this cohort study, a shorter TWFC was associated with higher risks of all-cause mortality, mortality from CVD and IHD, as well as incident CVD and IHD.