See the Health Tip below for a link to an comprehensive guide to therapeutic lifestyle changes (TLC).
Common medications to treat high cholesterol:
The following information from the Health Heart Handbook summaries the benefits and risk of the more available classes of cholesterol lowering drugs (2):
Statins (HMG-CoA Reductase Inhibitors):
These lower LDL levels about 20-55%, moderately lower triglycerides and raise HDL. Side effects are usually mild though liver and muscle problems may rarely occur. Recently, new concerns about statins in women have been raised and are discussed later in this publication.
This is a newer class of drugs that interferes with absorption of cholesterol in the intestine. They lower LDL by 18-25%. They are sometimes combined with a statin. Joint or back pain have been reported.
Bile acid resins:
These lower LDL by 15-30% and are often prescribed with a statin. Long term use is considered safe but side effects my include constipation, bloating , nausea and gas. Do not use these drugs if you have liver or gallbladder problems, bleeding issues, underactive thyroid, ulcers, or kidney disease.
Niacin lowers total cholesterol and LDL, lowers triglycerides while also raising HDL. It reduces LDL by 5-15% or more. Niacin is available over the counter but its side effect profile is high enough to warrant doctor oversight. Side effects include liver problems, gout, peptic ulcers and high blood sugar.
These reduce triglycerides by 20-50% while increasing HDL by 10-15%. They are not effective for lowering LDL cholesterol. Risks include the potential to develop gall stones and increase the effect of blood thinning drugs. They should not be used if you have kidney problems or liver disease.
Sex Differences that Affect Cholesterol Levels and Management
Low levels of HDL appear to be a stronger predictor of heart disease death in women than in men in the over-65 age group. High blood levels of triglycerides may be a particularly important risk factor in women and the elderly. Studies show that women's cholesterol is higher than men's beginning at age 45 and older. As women go through menopause, their lipid profiles change and become more atherogenic.
NIH researchers have found that women's cholesterol levels correspond with monthly changes in estrogen. This variation could indicate a need to take a women's monthly cycle into consideration while evaluating her cholesterol measures. On average, the cholesterol level can vary by as much as 19% during a woman's menstrual cycle. While we know that taking medications that include estrogen (HRT and birth control pills) can affect cholesterol levels, we are just beginning to learn about the effects of naturally occurring hormone levels on women's cholesterol. (3)
Women who have extensive artherosclerosis (plaque) may have a greater risk of cardiovascular events than men with similar hardening of the arteries depending on the type of plaque. Calcified plaque is considered more advanced and possibly more stable, while mixed plaque may be a sign of intermediate progression and possibly more dangerous. Noncalcified plaque is believed to indicate early disease and can rupture, causing a heart attack or death. Plaque can be pictured using CT angiograpy but more research is needed to help clarify whether or not the type of plaque has gender implications. (4)
The location of plaque-closed arteries is also important. Dr. Noel Bairey Merz and colleagues from the Women's Heart Center in Los Angeles found that women's hearts were less likely than men's to lose their ability to pump blood after a heart attack, and that female heart patients were less likely to present with obstructive coronary heart disease. Instead, the oxygen deprivation and subsequent damage to the heart in women is more likely to occur when small blood vessels, not major arteries become dysfunctional due to plaque accumulation.(5) This lack of identifying plaque in smaller vessels may be one reason women with heart disease are often misdiagnosed. A new type of cardiac magnetic resonance is being tested that is more capable of finding plaque in the smallest arteries.
Statins and Diabetes Risk
Older women who take statins may be at increased risk for developing type 2 diabetes according to an observational analysis of more than 153,000 women in the Women's Health Initiative database.(6) The researchers found that statin therapy was associated with a moderate increased risk for diabetes. Dosage and type of statin did not seem to make a difference implying a "medication class" risk. At this point in time, no changes have been made to clinical practice guidelines since benefits still seem to outweigh risks. Statins do a very good job in reducing risk for heart disease and stroke. However, the authors of the study suggest increasing vigilance for diabetic symptoms (thirst, frequent urination, blurred vision) and conducting more frequent blood sugar and liver function tests. This finding is likely to create more research on the mechanism of statins.
One of the interesting outcomes of this new study is the observation that obesity appeared to be protective against disease. Statin use was associates with a higher risk of diabetes in women with body mass index (BMI) scores below 25 than in those with BMIs above 30. These results have some clinicians wondering if we are putting too many aging women on statins because we thought the risks so low. It has been suggested that there be more efforts to try lifestyle modifications to reduce cholesterol before putting postmenopausal women on statins.
Status of Sex-based Research in Cardiology
The findings reported in this newsletter are good examples of why sex is so important in cardiology and that it is a fertile area for future sex-based research. A new report by the Institute of Medicine, Sex-specific reporting of scientific research: A workshop summary (2012) noted that only 27% of the participants in 19 randomized cardiology clinical trials were female and only 13 of the studies reported results by sex. One of the report authors noted that this bias was not necessarily intentional. Typical inclusion criteria may be the problem. For example, men have earlier onset of certain heart conditions that may favor their enrollment in clinical trials. Also, endpoints in a particular study may be different for men and women and thus study results may be biased if the endpoints are more male centric. In the future, researchers need to be more aware of reported sex differences in heart disease symptoms and physiology and consider them when designing future heart studies.