May 11, 2012

The Statin Controversy: Too Dangerous or Worth the Risk?

(Ivanhoe Newswire) -- A meta-analysis of multiple trials has left the medical world and patients concerned about statins and whether or not their benefits are worth their potentially harmful side effects.

Statins are a class of drugs that lower the amount of LDL cholesterol in the body by blocking the enzyme in the liver that makes cholesterol. Recently, there have been several studies that linked the drugs to an increased risk for new-onset diabetes.

One such study was the JUPITER study (Justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin; number, NCT00239681). The study included 17,802 participants without diabetes that had LDL cholesterol levels below 3.4 mmol per liter and high-sensitivity C-reactive protein levels of 2.0 mg per liter or higher. It was revealed that the hazard ratio for newly diagnosed diabetes increased 25% in the Rosuvastatin group versus the placebo group. Despite this fact, the participants who had a low risk for cardiovascular events had important health improvements over the following period of approximately 2 years, with a hazard rate 44% lower than the placebo group for cardiovascular events. Rates for treated participants were lower for the key secondary outcomes as well: 54% for myocardial infarction, 48% for stroke, 46% for revascularization, and 20% for death from any cause. Other studies confirm this trend in diabetes risk increase; a meta-analysis of six statin trials that included 57,593 participants showed a 13% increase in relative risk, and another meta-analysis of 13 randomized statin trials with 91,140 participants showed an odds ratio of 1.09 for a new diagnosis of diabetes.

The meta-analysis suggests a strong correlation between the risk of diabetes and the use of statins, but also raises an important question: should the risk of diabetes and the risk of cardiovascular events be weighted in a similar manner? 255 patients were treated with statins for 4 years, which resulted in one additional case of diabetes. Given the fact that statins are used by approximately 24 million Americans, the population-attributable risk for diabetes is considerably large. The good news is that 5.4 cardiovascular events out of 255 patients were prevented, and this must be considered in context with the negative findings.

The mechanism for the increased incidence of statin-induced diabetes is still unknown. There isn´t any data to suggest that a certain group is uniquely at risk, and because the studies were short term, it´s possible that the risk of diabetes will increase for the study participants in the future. Furthermore, the risk appears to be greatest for people who are already predisposed towards diabetes, considering factors such as older age, higher baseline fasting glucose levels, and other features of metabolic syndrome. Statins may just be unmasking the disease in people who were likely to develop diabetes anyway.

Because of the evidence presented in these studies, the Food and Drug Administration has added information to the statin labels about the possible effect on diabetes: "“¦increases in glycosylated hemoglobin and fasting serum glucose levels have been reported with statin use." Ultimately, the benefit for patients who have a high risk for cardiovascular events favors statin use, and statins should not be discontinued if diabetes is diagnosed.

Source:  The New England Journal of Medicine, May 2012