Smoking cessation and glycaemic control in type 2 diabetic patients

Aim: To elucidate the relationship between glycaemic control, blood pressure and body-weight change after smoking cessation in type 2 diabetic patients. Methods: We examined HbA(1c), blood pressure and body weight in 15 type 2 diabetic patients before, 6 and 12 months after quitting smoking. Sixteen type 2 diabetic patients who did not quit smoking served as control. Results: Body weight slightly increased after quitting smoking. Although HbA(1c) levels showed no change in the control group, those in patients who quit smoking significantly increased (6.8+/-0.3% before quitting smoking; 7.4+/-0.3% 6 months after quitting smoking, p<0.05; 7.8+/-0.4% 12 months after quitting smoking, p<0.001). Fasting blood glucose also increased in patients who quit smoking. The increase in body weight after quitting smoking did not correlate with the deterioration of glycaemic control. Diastolic blood pressure showed no change in control, whereas that in patients who quit smoking increased at month 12 (69 +/- 3 vs. 76 +/- 3 mmHg, p<0.01). The increase in HbA(1c) at month 12 after quitting smoking correlated with body mass index before quitting smoking (r=0.72, p<0.005) and serum triglyceride before quitting smoking (r=0.68, p<0.01). Conclusions: Glycaemic control and diastolic blood pressure deteriorated in type 2 diabetic patients after quitting smoking. Type 2 diabetic patients who want to stop smoking need a caution to prevent deterioration of glycaemic control and blood pressure after quitting smoking.