Two new studies presented recently at the American Diabetes Association (ADA) Scientific Sessions found previously unknown benefits for cholesterol– and triglyceride-lowering drugs in people with Type 2 diabetes. One study found that medicines from two different classes of lipid-lowering drugs reduced people’s risk of developing peripheral neuropathy; the other found that a drug in the statin class reduced the risk of certain cardiovascular events in people who recently had a stroke.
The first study followed a group of about 400 people with Type 2 diabetes for five years, looking at the effects of certain drugs on participants’ chances of developing peripheral sensory diabetic neuropathy, or nerve damage that causes sensations such as stinging, burning, tingling, pain, and numbness in the feet, legs, hands, and arms. The most common form of diabetic nerve damage, peripheral neuropathy ultimately affects about half of all people with diabetes.
The study found that people who took drugs in the statin or fibrate classes significantly reduced their risk of developing peripheral neuropathy. After controlling for changes in people’s HbA1c levels over time, the researchers found that those who took statins (which help lower LDL, or “bad,” cholesterol) cut their risk of peripheral neuropathy by 35%, while those who took fibrates (which help raise HDL, or “good,” cholesterol and lower triglycerides) cut their risk of peripheral neuropathy by 48%. After further statistical analysis, however, the researchers concluded that both classes of drugs actually had about the same effect on neuropathy prevention. The statins used in the study were atorvastatin (brand name Lipitor), pravastatin (Pravachol and others), and simvastatin (Zocor and others); the fibrates used were gemfibrozil (Lopid and others) and fenofibrate (TriCor and others).
While the mechanisms by which these drugs may help prevent peripheral neuropathy are not yet known, the researchers hypothesized that the benefits seen may be “class effects” of the drugs, meaning that they are consistent across different drugs in the same class. The researchers also suggested that since many people with diabetes already take these drugs to help prevent heart disease, rates of peripheral neuropathy may decrease in the future.
Another study presented at the ADA Scientific Sessions focused on the effect of one statin, atorvastatin, on almost 800 people with Type 2 diabetes who had recently had a stroke or transient ischemic attack (ministroke). The study found that treatment with an 80-milligram dose of atorvastatin significantly reduced the risk of another stroke and of coronary “events” such as chest pain, heart attack, and cardiac arrest when compared to treatment with a placebo. The risk of stroke fell by 30% and the risk of coronary events fell by 51% with atorvastatin treatment. Significant reductions in stroke risk were also seen in people who had the metabolic syndrome (a cluster of risk factors that raises a person’s chance of developing cardiovascular disease or Type 2 diabetes) and took atorvastatin following a stroke or ministroke.
These findings are significant because people with Type 2 diabetes have a risk of stroke two to four times higher than people without diabetes.