Smoking habits and type 2 diabetes mellitus in women

The purpose of this case–control study was to evaluate the relationship between smoking and type 2 diabetes mellitus (T2DM) in adult females. A total of 168 women in Kaunas, Lithuania with newly diagnosed T2DM during the year 2001 and 336 controls who were women without diabetes were recruited. Participants were asked about their duration of smoking, the number of cigarettes smoked per day, pack-years, and smoking cessation. Odds ratios (OR), 95 percent confidence intervals (CI) for T2DM were calculated using conditional logistic regression. After adjustment for possible confounders, women with T2DM had a nearly threefold higher odds for smoking 10 or more cigarettes per day compared with controls and using never smokers as the referent category (OR = 2.8; 95 percent CI 1.0–7.7). Women with T2DM had over fourfold odds for having smoked for 40 years or more compared to controls (OR = 4.6; 95 percent CI 1.1–18.6). Compared to controls, women with T2DM had over a sixfold higher odds for stopping smoking for 19 or fewer years with never smokers as the referent category (OR = 6.4; 95 percent CI 1.5–27.3). The findings of our study suggest a possible relationship between smoking and T2DM in women. Also, despite smoking cessation, the association with T2DM remained for a long time.