Abstract
BACKGROUND: The relationship between the time from waking to first cigarette (TWFC) and premature mortality remains unclear. This study aims to assess the association between TWFC and the risk of premature mortality, and to explore the role of accelerated biological aging in this relationship.
METHODS: A total of 309,308 participants from the UK Biobank were included in this study. We used the Klemera-Doubal method biological age (KDM-BA) and the phenotypic age (PhenoAge) algorithms to assess accelerated biological aging. The Cox proportional hazards regression model was performed to calculate the hazard ratio (HR) and 95 % confidence interval (CI) of premature mortality with TWFC.
RESULTS: During a median follow-up of 12.85 years, 14,725 premature deaths were identified. We observed that the shorter TWFC was associated with a higher risk of premature mortality (P trend < 0.001). Compared with subjects who never smoked, the adjusted HR (95 % CI) of premature mortality was 2.54 (2.28, 2.84) among subjects with TWFC < 5min. Similarly, participants whose TWFC < 5min had 8.955 (95 % CI, 8.951-8.958) months less time to premature death than those who never smoked at 12 years of follow-up. Moreover, accelerated biological aging partially mediated 10.35 %-24.57 % of the relationships between TWFC and risk of premature mortality.
CONCLUSIONS: A shorter TWFC is associated with an increased risk of premature mortality, and the association may be mediated by accelerated biological aging.