In Utero/Childhood/ Adolescence Exposure to Tobacco Smoke and Elderly-Onset Cataract: A Large Prospective Cohort Study.

PURPOSE

Cataract remains the primary cause of blindness in middle-income and low-income countries, with a known association with environmental factors including smoking. However, the relationship between early-life tobacco smoke exposures, including in utero tobacco smoke exposure and early initiation of smoking, and the risk of cataract incidence remains unclear. We aimed to examine the associations of early-life exposure to tobacco smoke with the risk of elderly-onset cataract.

METHODS

In this prospective study, we included 330,528 participants aged 40 years or older who were recruited between 2006 and 2010. Early-life tobacco smoke exposures, including in utero, childhood, and adolescence exposure to tobacco smoke, as well as the type of tobacco smoke, were ascertained based on questionnaires at baseline. Elderly-onset cataract was ascertained using hospital inpatient records and cataract surgery records. Multivariable-adjusted Cox proportional hazards models were used to examine the association between early-life tobacco smoke exposures and incident cataract. Additionally, the association between different types of tobacco smoke and cataract risk was also explored.

RESULTS

During a median follow-up of 12.04 years, 14,754 cases of incident cataract were documented. After adjusting confounders, the incidence of cataract significantly increased among participants with tobacco smoke exposures (hazard ratio [HR] = 1.13, 95% confidence interval [CI] = 1.09-1.18). Furthermore, individuals who were exposed to tobacco smoke in childhood (HR = 1.10, 95% CI = 1.03-1.21), adolescence (HR = 1.15, 95% CI = 1.10-1.21), and adulthood (HR = 1.12, 95% CI = 1.05-1.19) had an increased risk of cataract. Additionally, individuals who smoked cigars or pipes (HR = 1.26, 95% CI = 1.11-1.44), hand-rolled cigarettes (HR = 1.20, 95% CI = 1.05-1.36), and manufactured cigarettes (HR = 1.12, 95% CI = 1.08-1.17) were associated with an increased risk of cataract.

CONCLUSIONS

Individuals with early-life tobacco smoke exposures in childhood and adolescence significantly elevate the risks of cataract incidence in older age.

TRANSLATIONAL RELEVANCE

This study identified cataract-associated risks and suggested interventions like banning youth smoking to reduce future cataract incidence.