Background: The effect of glycemic control on the incidence of restenosis after percutaneous transluminal coronary angioplasty (PTCA) in non-insulin-dependent diabetes mellitus (NIDDM) has not been well analysed.
Methods: Out of 1282 consecutive patients who had undergone elective and successful PTCA over 8 years, 86 known to have NIDDM and 117 non-diabetic cases were analysed for restenosis following PTCA. Definition of restenosis is an increase from 50% to 75% diameter stenosis at the same lesion within 1 year after angioplasty. Those with familial hypercholesterolemia, renal failure, unstable angina pectoris, bypass graft surgery within 1 month were excluded. Blood pressure, body mass index, history of smoking, fasting blood glucose, post-prandial glucose, HbA1c, cholesterol, triglycerides, number of stenotic vessels, restenosis rate were studied - 6 months before PTCA and 1, 3, 6 and 12 months after PTCA.
Results: The frequency of restenosis within 1 year of PTCA was significantly greater in poorly controlled NIDDM (75%) than in well or moderately controlled NIDDM (30-40%) or non-diabetic subjects (33%). Multivariate analysis showed that the degree of control of diabetes was significantly correlated with restenosis.
Conclusion: Restenosis following elective and successive PTCA was significantly more frequent in poorly controlled NIDDM compared with moderately or well-controlled NIDDM or non-diabetic subjects. Multivariate analysis also showed the significant correlation between restenosis and glycemic control. These findings indicate that control of diabetes plays an important role in reducing restenosis after PTCA.