Is cigarette smoking associated with impaired physical and mental functional status? An office-based survey of primary care patients.

OBJECTIVE: To examine the relationship between cigarette smoking and self-reported physical and mental functional status.
DESIGN: Cross-sectional survey of 837 patients visiting 2 family-practice centers. Patients completed a self-administered survey about functional status, tobacco use, and demographic characteristics while waiting to be called back for their appointments.
SETTING: An inner-city family practice clinic in Richmond, Virginia, and a more affluent suburban practice outside Washington, DC. MAIN OUTCOME MEASURES: Physical and mental functional status, as measured by the SF-36 (Medical Outcomes Trust, Boston, MA); current and former cigarette use; and demographic variables (age, gender, education, income).
RESULTS: Among current smokers, self-reported functional status scores were significantly lower than those of nonsmokers in all SF-36 domains (p < or = 0.02), a pattern that was more dramatic for mental functional status domains (social function, vitality, emotional role limitations, mental health). In several SF-36 domains, a dose-response relationship between smoking and functional status was noted. After multivariate adjustment for demographic confounders and practice site, the statistical significance of these differences diminished considerably, but it remained significant for certain domains and for the overall difference across all domains (MANCOVA p = 0.017).
CONCLUSIONS: Current smokers report lower functional status than nonsmokers, in physical and especially in mental domains. The meaning of this cross-sectional relationship is unclear without further longitudinal study. Smoking may be associated with other variables that have a causal role.