It has become evident how coronary heart disease has affected the lives of many. As the heart is the central organ of our body, dysfunction leads to failure in the functioning of other various organs. A person suffering from heart disease undergoes tremendous physical and mental stress, and it most often leads to disability, lower quality of life, and worst, death. According to the National Vital Statistics Report, 2010, it is the number one cause of all deaths in the U.S. and worldwide. The United States alone has more than 18 million people with coronary heart disease. Statistically, there are 18.7 million people in the U.S. with a history of heart attack and/or angina. Another 6.4 million have had a stroke, and 8 million have peripheral artery disease (PAD). In addition, the cost of treating heart disease in the U.S. will triple by 2030. Because of this high prevalence of global death and financial burden owing to heart disease, The National Heart, Lung, and Blood Institute (NHLB) found it urgent to implement strategies to prevent this epidemic. Thus, they developed a study called AIM-HIGH which has prominent use of niacin.
For over fifty years in clinical practice, niacin (vitamin B3) has been widely prescribed for managing dyslipidemia (high blood cholesterol levels). Niacin has a broad range of effects on serum lipids and lipoproteins, including lowering total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides primarily by decreasing fatty acid mobilization from adipose tissue. It is currently the most effective lipid-modifying agent in increasing high-density lipoprotein cholesterol (HDL-C) for patients with very low levels. Niacin also has the ability to lower levels of atherogenic lipid parameters in patients with mixed dyslipidemia, suboptimal LDL-C control, or statin intolerance. The beneficial effects of niacin on levels of atherogenic and protective lipids are further supported by evidence that early formulations of niacin had a favorable cardiovascular effect. Given this data, niacin was noted a viable therapeutic option.
The AIM-HIGH trial tested whether extended-release niacin added to extensive statin therapy, as compared with statin therapy alone, would reduce the risk of cardiovascular events in patients with established atherosclerotic CVD and atherogenic dyslipidemia.
Unfortunately, AIM-HIGH was stopped in May 2011 without having formal results revealed until November. The time gap allowed for widespread speculation in media coverage of the reasons underlying the failure of efficacy and potential mechanisms leading to an increase in stroke risk. This also gave rise to uncertainty in clinical practice about whether to continue the use of niacin for cardiovascular risk prevention.
The recent publication of the AIM-HIGH trial addressed this issue. The trial was stopped early because an interim analysis found that the patients who took extended-release niacin had no clinical benefit. In addition, it found the speculation toward more ischemic strokes statistically insignificant.
Overall, among patients with atherosclerotic cardiovascular disease and lowered levels of LDL cholesterol, there was no incremental clinical benefit from the addition of niacin-statin therapy during a 36-month follow-up period, despite significant improvements in HDL cholesterol and triglyceride levels. In health care, physicians and even Registered Dieticians require sound answers to such studies. Studies like AIM-HIGH made it blatant that the answers to CVD prevention are still lacking. However, the outcome can affect our recommendations and reliable guidance. From the Registered Dietician’s perspective, it is vital to be aware of cholesterol levels and the effects of different medications. Participants in such studies would have to adhere to diets that will not have adverse effects due to food-drug interactions, and uncontrolled cholesterol levels attained through food.
Beyond this issue, it is important to note that we all should not rely on medicine because it cannot cure or prevent all things such as our predominant cause of death in the world. Though we cannot cure or prevent heart disease through niacin, the best health professionals, RD’s included, can offer is prevention. This involves making good recommendations, setting patients healthy eating goals that reduce the consumption of low-density-lipoprotein (LDL) cholesterol, and guiding patients to healthier lifestyles via education.
