Factors associated with diabetes control : results of a 2-year cohort study of outpatients with type 2 diabetes

Type 2 diabetes is a typical lifestyle disease. We aimed to identify the factors affecting glycemic control in 64 outpatients with type 2 diabetes over a 2-year period. We defined poor glycemic control using a change in glycosylated hemoglobin (ΔHbA1c) of ≥ 0.5% over 2 years and/or HbA1c ≥ 7.5% at the end of the study period. We used a questionnaire to collect information on oral health behavior and lifestyle, including eating and smoking habits, and analyzed the relationships between indices of diabetes control and responses to the questionnaire. The mean (SD) HbA1c of the participants was 6.87% (0.77%) at a baseline, and 6.93% (0.69%) after 2 years. Twenty-three participants (36.0%) had poor glycemic control. ΔHbA1c and the change in body mass index (ΔBMI) correlated (Spearman’s rank correlation, r = 0.350, p < 0.01). The HbA1c at baseline was associated with eating slowly / chewing well, and ΔBMI was associated with perceived oral symptoms. Binominal logistic regression analysis revealed that poor glycemic control was associated with ΔBMI and a smoking habit (odds ratio : 1.62, 95% confidence interval : 1.08–2.42 ; and 4.01, 1.12–14.36, respectively). These findings imply that weight gain and a smoking habit are associated with poor glycemic control in patients with type 2 diabetes.