Control Improves

Improved blood glucose control is associated with a number of effects that could contribute to a reduction in the risk of clinical cardiovascular events such as myocardial infarction and stroke. Improved glycemia lowers PAI-1 concentrations and reduces platelet adhesiveness and aggregability. Chronic amelioration of hyperglycemia reduces glycation of proteins in the arterial wall and in circulating lipoproteins. Improved glycemia is associated with an amelioration of the circulating lipid abnormalities, especially the elevated triglycerides and low HDL cholesterol that are typical of poorly controlled type 1 or type 2 diabetes. No clinical trial has been conducted exclusively in patients with diabetes to determine the effects of lipid lowering per se on cardiovascular events. However, several lipid-lowering trials have included patients with type 2 diabetes. Post hoc analysis of those trials is informative about the potential role of hyperlipidemia in the genesis of atherosclerosis in patients with diabetes. The topic has also been reviewed recently by Goldberg (see Suggested Reading).

In the Scandinavian Simvastatin Survival Study (4S), simvastatin significantly reduced coronary mortality (42%) in the 2221 subjects randomized to lipid-lowering therapy relative to the 2223 placebo-treated subjects. Total mortality -o was also significantly reduced (30%) in the simvastatin-treated group. In the sub- |

group of 202 diabetic subjects, coronary events were significantly reduced (55%) £

with lipid-lowering therapy. Coronary and total mortality were nonsignificantly g reduced (28% and 21%, respectively). All subjects in 4S had established cardio- <j vascular disease prior to randomization and the average LDL-C level prior to treatment was 186 mg/dL in the subgroup of diabetic subjects. In the Cholesterol J

and Recurrent Events (CARE) study, coronary mortality was reduced 24% in the

2081 subjects randomized to pravastatin therapy relative to the 2078 subjects randomized to placebo treatment. Lipid-lowering therapy in CARE significantly reduced coronary events (25%) in the subgroup of 586 diabetic subjects. CARE was a secondary prevention trial and all subjects randomized to this trial had a previous myocardial infarction. The baseline LDL-C level was 136 mg/dL in the subgroup of diabetic subjects. In the Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) trial, coronary death was significantly reduced (24%) in the 4512 subjects randomized to pravastatin therapy relative to the 4502 subjects randomized to placebo treatment. Total mortality was also significantly reduced (22%) in the pravastatin-treated group. Lipid-lowering therapy in LIPID reduced fatal and nonfatal myocardial events 19% in the subgroup of 782 diabetic subjects. LIPID was a secondary prevention trial and the baseline LDL-C level was 150 mg/dL in the subgroup of diabetic subjects. The Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS) was a primary prevention trial in which the primary endpoint of fatal or nonfatal myocardial infarction, unstable angina, or sudden death was reduced 37% in the 3304 subjects treated with lovas-tatin relative to the 3301 subjects randomized to placebo. Lipid-lowering therapy reduced the primary endpoint 42% in the subgroup of 155 diabetic subjects. Baseline LDL-C in this trial was 150 mg/dL.

In summary, aggressive LDL-lowering therapy that resulted in LDL-C reductions of 25 to 35% reduced recurrent and first cardiovascular events by 19 to 55% in subjects with diabetes mellitus. Although these trials were not specifically designed to determine the effects of lipid lowering in diabetic subjects, they clearly indicate benefit in this subgroup of individuals equal to or greater than nondiabetic subjects. The optimum goal for LDL-C levels in diabetic subjects is less than 100 mg/dL and for total triglyceride levels, less than 150 mg/dL. Every effort to raise HDL-C to the highest level possible should be attempted. Optimum control of hyperglycemia usually results in optimization of triglyceride and HDLC levels.

Your Heart and Nutrition

Your Heart and Nutrition

Prevention is better than a cure. Learn how to cherish your heart by taking the necessary means to keep it pumping healthily and steadily through your life.

Get My Free Ebook

Post a comment