Faculty Bibliography

Cardiovascular disease remains the leading cause of death in most of the developed world despite advances in both prevention and treatment. At the same time, the incidence rates of cardiovascular disease differ greatly between the genders, with men more likely than women to manifest ischemic heart disease. This observation has prompted new research initiatives to explain the discrepancy in heart disease prevalence and incidence between the sexes. Whether androgens affect cardiovascular disease adversely remains a contentious issue, with some data pointing to a deleterious effect of androgens on lipid profiles, and other studies revealing androgens' possible benefits on cardiovascular function. This review will examine the relationship between the endogenous production of androgen as well as the exogenous replacement of testosterone in men and the possible links to cardiovascular disease. The role of testosterone in male cardiovascular health is not completely understood, and additional studies are needed to explain its effect on atherosclerosis and its complications.

Lifestyle modifications and pharmacologic therapy have been the mainstays of treatment for patients with type 2 diabetes mellitus. Bariatric surgery, originally designed as a weight loss treatment, has been proven to ameliorate and even cure diabetes. The significant improvement in glycemic control found after bariatric surgery in patients with diabetes often precedes major weight loss. Therefore, a weight-independent mechanism has been thought to initiate this amelioration in glucose control. Reviews of the recent literature question the goal of bariatric surgery, not only to treat obesity through restriction and malabsorption, but also as a possible treatment for diabetes regardless of the degree of obesity. Procedures such as Roux-en-Y gastric bypass, adjustable gastric banding, and biliopancreatic diversion have proven to be extremely effective in controlling diabetes mellitus. Mechanisms explaining the effectiveness of weight reduction surgery include effects on incretins, ghrelin secretion, and insulin sensitivity. Some centers have been performing gastric bypass surgeries on patients with a lower body mass index than that recommended by current NIH guidelines. New considerations for recommending bypass surgery are warranted as the indications for antiobesity surgeries grow to encompass both the treatment and cure of diabetes.

As the diabetic population has significant morbidity and mortality from cardiovascular disease (CVD), much of its medical care focuses on CVD prevention and treatment. Some medications used to treat hyperglycemia may have beneficial effects on CV outcomes, others may have negative effects, while still others seem to have no direct effect. Although past epidemiological studies have shown a relationship between glycated hemoglobin levels and CV events in patients with type 2 diabetes, recent large randomized clinical trials (ACCORD, ADVANCE, and VADT) lasting 3.5 to 5.6 years have found that intensive glycemic control either has no impact on CV outcomes or even worsens them. Results of the 10-year follow-up of the UKPDS suggest that tight glycemic control of younger, newly diagnosed patients with type 2 diabetes may have CV benefits many years later. Because the pathogenesis of atherosclerosis spans decades, it may be that beneficial effects of tight glycemic control on CV outcomes are mainly in younger patients without established macrovascular disease. There is an emerging notion that tight glycemic control may be beneficial in primary prevention of CVD in younger patients with diabetes, but may become deleterious in older patients with established or subclinical CVD. Thus, while tight control may lessen microvascular disease, it may increase the risk of hypoglycemia and possibly of adverse CV events. In each patient, the goals of glycemic control need to be individualized based on age, overall prognosis, presence of macrovascular disease, and risk of hypoglycemia.