Debunking the Myth of Diabetes Mellitus as Cardiovascular Disease Equivalent: What Took So Long?
Purpose of Review
Individuals with diabetes mellitus (DM) have historically been reported to have the same risk of having a future myocardial infarction (MI) as an individual with known coronary heart disease (CHD). In other words, DM has been widely accepted as a coronary heart disease (CHD) equivalent. We review the literature that established DM as a CHD risk equivalent and how over time it has become clear that DM carries a spectrum of risk.
Newer studies suggest that DM is heterogeneous, with certain subgroups such as women, those with longer duration of DM, and increased severity of disease may be more susceptible to downstream complications and cardiovascular events than those in other subgroups. The use of coronary artery calcium scoring for risk stratification in this group has now been shown to have clinical utility.
DM surely does infer increased risk of developing coronary heart disease upon an individual; however, this risk is not as high as historically presumed. Certain subgroups among the DM population may have a higher risk of CHD when identified by burden of subclinical disease; these individuals can be identified early to begin personalized management of their disease.
KeywordsDiabetes mellitus Coronary artery disease Coronary heart disease CHD risk equivalent Coronary calcium
Compliance with Ethical Standards
Conflict of Interest
Shaista Malik and Erum Iqbal Bajwa declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
- 1.• Centers for Disease Control and Prevention. National Diabetes Statistics Report, 2017. Atlanta: Centers for Disease Control and Prevention, U.S. Dept of Health and Human Services; 2017. This reference is a periodic publication from the Centers for Disease Control and Prevention (CDC) that provides updated statistics about diabetes in the USA for a scientific audience. The estimates in this document were derived from various data systems of CDC, including the Indian Health Service (IHS), the Agency for Healthcare Research and Quality (AHRQ), the U.S. Census Bureau, and published studies. The estimated percentages and the total number of people with diabetes and prediabetes were derived from the National Health and Nutrition Examination Survey (NHANES), National Health Interview Survey (NHIS), IHS National Data Warehouse (NDW), Behavioral Risk Factor Surveillance System (BRFSS), United States Diabetes Surveillance System (USDSS), and US resident population estimates. This reference was used in establishing the current statistics of diabetes and its current burden in the USA. This provided a framework for understanding the prevalence of heart disease amongst diabetics. This allowed for the further discussion of CHD equivalence in the context of a large and growing population established in the USA. Google Scholar
- 9.Vaccaro O, Eberly LE, Neaton JD, Yang L, Riccardi G, Stamler J. Impact of diabetes and previous myocardial infarction on long-term survival: 25-year mortality follow-up of primary screeners of the Multiple Risk Factor Intervention Trial. Arch Intern Med. 2004;164:1438–43.CrossRefPubMedGoogle Scholar
- 10.Hu G, Jousilahti P, Qiao Q, Katoh S, Tuomilehto J. Sex differences in cardiovascular and total mortality among diabetic and non-diabetic individuals with and without history of myocardial infarction. Diabetologia. 2005;48:656–66.Google Scholar
- 11.Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive summary of the third report of the National Cholesterol Education Program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (adult treatment panel III). JAMA. 2001;285(19):2486–97.CrossRefGoogle Scholar
- 15.Daniels LB, Grady D, Mosca L, Collins P, Mitlak BH, Amewou-Atisso MG, et al. Raloxifene Use for the Heart (RUTH) trial investigators. Is diabetes mellitus a heart disease equivalent in women? Results from an international study of postmenopausal women in the Raloxifene Use for the Heart (RUTH) trial. Circ Cardiovasc Qual Outcomes. 2013;6:164–70.CrossRefPubMedGoogle Scholar
- 16.Goff DC Jr, Lloyd-Jones DM, Bennett G, American College of Cardiology/American Heart Association Task Force on Practice Guidelines, et al. 2013 ACC/AHA guideline on the assessment of cardiovascular risk: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2014;63(25 Pt B):2935–59.CrossRefPubMedGoogle Scholar
- 18.•• Rana JS, Liu JY, Moffet HH, Jaffe M, Karter AJ. Diabetes and prior coronary heart disease are not necessarily risk equivalent for future coronary heart disease events. J Gen Intern Med. 2016;31:387–93. These authors and researchers from Kaiser Permanente Northern California health system and University of California, San Francisco, used data from the Kaiser Permanent Northern California to conduct a population-based prospective cohort analysis to revisit the concept of risk equivalence by comparing the risk of subsequent CHD events among individuals with or without history of diabetes or CHD in a large contemporary real-world cohort over a period of 10 years (2002 to 2011). They established four different groups of patients categorized by prevalence or absence of diabetes and coronary heart disease. They found evidence that not all individuals with diabetes should be unconditionally assumed to be a risk equivalent of those with prior CHD. In contrast, the concept of CHD equivalence of diabetes has been widely accepted and this was presented in support of particular sub-groups with diabetes being considered at higher risk than others. Google Scholar
- 21.Malik S. Excess Risk of Stroke in Women: The Role of Diabetes Mellitus. Nat Rev Endocrinol. 2014;10:318–320.Google Scholar
- 23.Barrett-Connor E. The Rancho Bernardo Study: 40 years studying why women have less heart disease than men and how diabetes modifies women’s usual cardiac protection. Glob Heart. 2013;8(2) https://doi.org/10.1016/j.gheart.2012.12.002.
- 28.Malik S, Budoff MJ, Katz R, Blumenthal RS, Bertoni AG, Nasir K, et al. Impact of subclinical atherosclerosis on cardiovascular disease events in individuals with metabolic syndrome and diabetes: the multi ethnic study of atherosclerosis. Diabetes Care. 2011;34:2285–90.CrossRefPubMedPubMedCentralGoogle Scholar
- 31.Malik S, Zhao Y, Budoff M, Nasir K, Blumenthal RS, Bertoni AG, et al. Coronary artery calcium score for long-term risk classification in individuals with type 2 diabetes and metabolic syndrome from the multi-ethnic study of atherosclerosis. JAMA Cardiol. 2017;2:1332–40. https://doi.org/10.1001/jamacardio.2017.4191.CrossRefPubMedPubMedCentralGoogle Scholar