Worried about Heart Health? Understanding the Roles of Nutrition and Drugs
According to JAMA, a new class of lipid-lowering agents, PCSK-9 inhibitors, are being developed to treat patients with hyperlipidemia. These expensive specialty medications will be targeted to the 73 million adults (32%) in the US with elevated cardiovascular risk (elevated LDL-C). The authors fear these drugs will not be adopted because the American Heart Association (AHA) and American College of Cardiology (ACC) abandoned specific LDL-C target guidelines in 2013.
The AHA/ACC stated goals are to prevent cardiovascular disease and improve the management of those with disease. The 2013 guidelines established primary prevention and secondary treatment goals based on the intensity of statin therapy and identified 4 treatment groups. The ACC/AHA committee reviewed RCTs involving omega-3 fatty acids and nicotinic acid forms. In Table 2, it reads “Nonstatin therapies, as compared with statin therapies, do not provide acceptable ASCVD (atherosclerotic cardiovascular diseases) risk-reduction benefits relative to their potential adverse effects in the routine prevention of ASCVD.”
The role of omega-3 fatty acids in CVD, both primary prevention and the management of individuals with CVD, is under review. At least one entity, the Agency for Healthcare Research and Quality (AHRQ), is evaluating the scientific evidence for using omega-3 fatty acids to prevent cardiovascular disease and the management of individuals with heart disease. The AHRQ has issued their draft report, and is seeking input. What might I want the AHRQ to know?
Even within the realm of placebo-controlled statin trials, experts question the value of lowering specific CVD biomarkers. Unlike prescription drugs, nutrition-related RCTs are much more complex to interpret because they lack a true placebo treatment. Everyone has some level of intake and exposure.
Many of the omega-3 trials have been too underpowered to detect an effect of n-3 fatty acids. In one of the more recent meta-analyses, 15 of 20 omega-3 RCTs involved patients being treated with prescription medications (13 using lipid lowering prescription drugs and 9 using statins). Why does this matter?
Statins can lower serum docosahexaenoic acid (DHA) concentrations and the DHA/AA (arachidonic acid) ratio. Thus, patients being medically treated for CVD may need more omega-3 fatty acids to maintain similar EPA+DHA concentrations in the circulation of healthy individuals trying to prevent cardiovascular disease.
Experts take heed. To determine the health benefits of omega-3s (and other nutrients as well), it is important to apply the guiding principles for nutrition studies published by Dr R Heaney: 5 principles for nutrition evidence from individual studies and 6 principles for systematic reviews and/or meta-analyses.
For consumers. Who wouldn’t want to maintain healthy circulating EPA+DHA concentrations? At $0.25 per day, an investment in omega-3 supplements is safe. More importantly, it helps support your brain and eyes as well as your heart.
Shrank WH, Barlow JF, Brennan TA. New therapies in the treatment of high cholesterol: An argument to return to goal-based lipid guidelines. 2015 JAMA doi: 10.1001/jama.2015.10017
Thanassoulis G, Williams K, Ye K, Brook R, Couture P, Lawler PR, de Graaf J, Furberg CD, Sniderman A. Relations of change in plasma levels of LDL-C, non-HDL-C and apoB with risk reduction from statin therapy: A meta-analysis of randomized trials. J Am Heart Assoc doi: 10.1161/JAHA.113.000759
Stone NJ, Robinson JG, Lichtenstein AH, Bairey Merz CN, Blum CB, Eckel RH, Goldberg AC, Gordon D, Lloyd-Jones DM, McBride P, Schwartz JS, Shero ST, Smith Jr SC, Watson K, Wilson PWF. 2013 ACC/AHA guideline on the treatment of blood cholesterol to reduce atherosclerotic cardiovascular risk in adults. 2014 JACC doi: 10.1016/j.jacc.2013.11.002
Scientific Information Request on Omega 3 Fatty Acids and Cardiovascular Disease – Update. US Dept of Health & Human Services, Agency for Healthcare Research and Quality. Updated Aug 12, 2015
Draft Systematic Review: Omega-3 fatty acids and cardiovascular disease: An updated systematic review. 2015 US Dept Health & Human Services. Agency for Healthcare Research and Quality. Accessed online Aug 12, 2015
Heaney RP. Guidelines for optimizing design and analysis of clinical studies of nutrient effects. 2014 Nutr Rev doi: 10.1111/nure.21090
Mozaffarian D, Wuy JHY. Omega-3 fatty acids and cardiovascular disease: Effects on risk factors, molecular pathways, and clinical events. 2011 J Am Coll Cardiol doi: 10.1016/j.jacc.2011.06.003
Rizos EC, Ntzani EE, Bika E, Kostapanos MA, Elisaf MS. Association between omega-3 fatty acid supplementation and risk of major cardiovascular events: a systematic review and meta-analysis. 2012 JAMA doi: 10.1001/2012.jama.11374