Inhaled medication usage in post-menopausal women and lifetime tobacco smoke exposure: The Women's Health Initiative Observational Study.

Objective: While active smoking is a causal agent in respiratory disease, the independent role of secondhand smoke (SHS) merits further investigation. We investigated associations between lifetime active smoking and exposure to secondhand smoke - studied independently - and current use of 1 or more inhaled medications as a surrogate for prevalent pulmonary disease in post-menopausal women.

Study Design: Information on lifetime active and passive tobacco exposure and inhaled pulmonary medication usage at enrollment was collected from 88,185 postmenopausal women aged 50-79 enrolled in the Women's Health Initiative Observational Study from 1993 to 1998 at 40 centers in the United States.