Smoking status, physical health-related quality of life, and mortality in middle-aged and older women.

INTRODUCTION: Women who smoke, particularly older women, have been relatively neglected in smoking research. There is a lack of knowledge concerning the relation of level of smoking to quality of life and mortality among middle-aged and older women smokers.
METHODS: This study examined the relation of smoking status to physical health-related quality of life (PHRQL) and total mortality in women in the Women's Health Initiative (WHI) Observational Study. Participants were 90,849 postmenopausal women, who were an average age of 63.6 years at baseline. Analyses used multiple linear and Cox proportional hazards regression and controlled for age, educational level, and ethnicity. Never-smokers were the reference group.
RESULTS: We found that smoking status was significantly related to PHRQL cross-sectionally at baseline and prospectively at a 3-year follow-up, with those who smoked having lower PHRQL. Heavier smokers showed large, clinically meaningful associations with PHRQL and light smokers showed small associations. In addition, we found that the smoking status at baseline was significantly related to 10-year total mortality. Both light and heavier smoking at baseline significantly correlated with higher mortality risk; however, the relationship of smoking to mortality was dose dependent. Among former smokers, those who had smoked longer showed significantly lower PHRQL and significantly increased mortality risk.
CONCLUSIONS: Findings suggest that the risks of smoking may not be evident to light smokers and that educational interventions targeted to middle-aged and older women stressing the consequences of light smoking may be particularly beneficial.