Race and gender differences in the effects of smoking on lung function.

STUDY OBJECTIVE: To assess the extent to which the relationship between smoking and lung function in adults varies by gender and race/ethnicity.

DESIGN: A random-effects metaregression analysis to synthesize results from common cross-sectional regression models fit to participants in each of 10 gender-race strata in each of eight large population-based observational studies or clinical trials.

SETTING: Source data collected as part of the most recently completed examination cycle for each of the participating studies.

PARTICIPANTS: Participants ranged in age from 30 to 85 years, although the age, race, gender, and general health characteristics of each of the populations varied greatly.

INTERVENTIONS: Most of the studies were observational in nature, although some did involve lifestyle interventions. All treatment assignments were ignored in the analysis.

MEASUREMENTS AND RESULTS: All studies measured lung function using standardized methods with centrally trained and certified technicians. Study findings confirm statistically significant, dose-related smoking effects in all race-gender groups studied. Significant gender differences in the effects of cigarette smoking were seen only for blacks; black men who smoked had greater smoking-related declines in FEV(1) than did black women. This effect was present in only one of two smoking models, however. Significant racial differences in the effects of smoking were seen only for men, with Asian/Pacific Islanders having smaller smoking-related declines than white men in both models.

CONCLUSIONS: In summary, this analysis generally failed to support the hypothesis of widespread differences in the effects of cigarette smoking on lung function between gender or racial subgroups.