Purpose: To review information on the implications of insulin resistance for type II diabetes mellitus (non-insulin-dependent diabetes mellitus) and coronary heart disease, and to derive guidance from this information for the management of these conditions.
Data sources: A MEDLINE search of English-language articles published between 1985 and July 1996, and review of the bibliographies of articles obtained through the MEDLINE search and textbooks.
Study selection: Primary research articles, reviews and perspectives on the epidemiology of diabetes and cardiovascular diseases and on intervention outcomes in these diseases.
Data extraction: Study design and quality were assessed, with particular attention to methods, study population size and other characteristics. Conclusions of review articles and perspectives were analyzed critically.
Data synthesis: Type II diabetes is associated with a two- to fourfold excess of coronary heart disease, compared to nondiabetic populations. In most studies, glycemia and duration of clinical diabetes were found to be only weak risk factors for coronary heart disease. Conventional coronary heart disease risk factors such as dyslipidemia and hypertension have been associated with coronary heart disease in type II diabetes subjects. Hyperinsulinemia and insulin resistance have been predictive of the development of type II diabetes and, in some studies, of coronary heart disease.
Conclusion: Strategies to prevent the development of coronary heart disease in diabetic and possibly prediabetic subjects should emphasize a multifactorial approach, including: a) improved glycemic control; b) aggressive treatment of risk factors for coronary heart disease, including insulin resistance; c) primary prevention of NIDDM; and d) use of glucose lowering agents that improve insulin sensitivity and cardiovascular risk factors.