The association between smoking and the prevalence of intermittent claudication.

The objective of this study was to investigate the association between smoking and the prevalence of intermittent claudication (IC). Between 1995 and 1997, all residents aged 20 years or older in Nord-Trøndelag County, Norway, were invited to take part in the Nord-Trøndelag Health Study (Helseundersøkelsen i Nord-Trøndelag: HUNT 2). A total of 19748 participants aged 40-69 years attended. Responses to 12 questions on IC (including a Norwegian translation of the Edinburgh Claudication Questionnaire) had been previously tested against the ankle-brachial pressure index (ABPI < 0.9), and an algorithm of the best test properties was used to identify people with IC. Using logistic regression analysis we computed age-adjusted prevalence odds ratios (OR) for the association between smoking and IC. Both current (ORmen = 3.8, confidence interval (CI) 2.1-6.7, ORwomen = 2.2, CI 1.4-3.4) and former smokers (ORmen = 1.7, CI 0.9-3.2, ORwomen = 1.7, CI 1.1-2.7) had a higher prevalence of IC compared with those who had never smoked, and individuals who had stopped smoking more than 20 years previously had a substantially lower prevalence of IC (ORmen = 0.2, CI 0.1-0.5, ORwomen = 0.4, CI 0.2-0.8) than current smokers. We found no association between passive smoking and IC in either men or women. Current and previous smoking habits were positively associated with the prevalence of IC, and smoking cessation was negatively associated in men and women. Passive smoking was not associated with IC in this study.