Comprehensive assessment of lifetime cigarette smoking and its association with health-related quality of life among older US adults

Cigarette smoking has a modest association with health-related quality of life (QOL), largely due to its causal role in cancer, cardiovascular disease, and chronic lung disease. However, prior studies have often underestimated exposure by using limited measures of smoking, by including young adults, and by adjusting for smoking related diseases—which mediate the association. We aimed to examine the association between a comprehensive index of lifetime cigarette smoke exposure (LCSEI) and QOL among older adults in the USA. We analyzed data for 7,001 U.S. adults ≥ 40y from an available US sample (wave 5 of the Population Assessment of Tobacco and Health Study). The 11-point LCSEI included heaviness of smoking, pack-years, childhood smoking, and second-hand smoke exposure. QOL measures included PROMIS global physical and mental health (GPH, GMH) scores. We estimated the multivariable association between LCSEI scores and mean GPH or GMH, adjusting for sociodemographics, BMI, and weekly exercise but not smoking-related diseases. Regarding lifetime smoking, 6.7% smoked during childhood, and 16.9% currently smoked. In the multivariable analysis, high vs. low LCSEI was associated with significant reductions in mean GPH (−14.5%) and GMH (−15.2%), significantly more than reductions for extremes of education (−3.0% and −5.3% respectively) and comparable to extremes of income (−10.9% and −11.4% respectively). Sensitivity analysis found that associations were greatly attenuated but remained significant even after further adjustment for smoking-related diseases. Among older adults, reducing lifetime cigarette smoking could yield gains in QOL similar in magnitude to those associated with narrowing socioeconomic inequalities, highlighting importance of eliminating cigarettes to promote healthy aging. For the poor, disadvantage delivers a double blow to QOL: directly, through the material hardships of poverty, and indirectly, through greater lifetime exposure to cigarette smoke.