Diabetes Mellitus and the Cardiovascular System

Abstract

Diabetes mellitus (DM) is an epidemic which affects close to 100 million patients worldwide; the majority being type 2 diabetes mellitus. The rising incidence has resulted in a proportional increase in the frequency of cardiovascular disease attributable to DM, as revealed by various population-based studies. Over the past 50 years, DM has been shown to be an important and independent risk factor in the development of a variety of cardiac conditions, especially vascular disease, primarily through accelerated atherosclerosis. Diabetic neuropathy is a serious complication of DM, which leads to the impairment of cardiovascular autonomic control. Diabetic cardiac autonomic neuropathy results in heart rate abnormalities, exercise intolerance, orthostatic blood pressure abnormalities, QT interval prolongation, silent ischemia and diabetic cardiomyopathy, all of which lead to increased morbidity and mortality related to diabetes. This conditions remains difficult to diagnose and treat, requiring a multifaceted approach. Inflammation appears to play a central role in accelerating many of the injurious effects of DM on the cardiovascular system. Expression of specific inflammatory markers has been directly linked to some of the known harmful effects of DM on the cardiovascular system, in addition to indirectly potentiating the deleterious effects of other major cardiovascular disease risk factors. Hyperglycemia results in increased intracellular glucose which triggers several pro-inflammatory reactions leading to the production of harmful free radicals and the formation of advanced glycation end products. These have been linked to the development of diabetic atherogenic dyslipidemia, in addition to glycation and loss of the protective effect of high density lipoproteins in diabetic subjects, thereby worsening the atherosclerotic burden in DM. Addressing hyperglycemia, therefore, is only one of many vital components in the treatment of diabetes. Traditional risk factors for heart disease and stroke tend to be further potentiated by the presence of DM, however, even after adequate control of hyperglycemia. Clinical evidence and major clinical guidelines address this conundrum by pointing out unmet needs of adequate cardiovascular protection, and call for aggressive control of risk factors in the diabetic population.




J Endocrinol Metab. 2015;5(6):313-320
doi: http://dx.doi.org/10.14740/jem324e