Thursday, January 3, 2019

The new cholesterol guidelines: What you need to know

If you’re a smoker looking for another reason to quit, consider this: in addition to raising your risk of heart and lung disease, as well as cancers of the bladder and kidney, smoking could boost the odds that you will develop aggressive prostate cancer that metastasizes, or spreads through your body. That’s according to research published by an Austrian team in 2018.

The evidence connecting tobacco use with prostate cancer (which tends to grow relatively slowly) isn’t as strong as it is for other smoking-related diseases. Researchers first detected the link only after pooling data from 51 studies that enrolled over four million men. Published in 2014, this earlier research showed that smokers have a 24% higher risk of death from prostate cancer than nonsmokers, but it left an open question: did the men who died from these other causes also have high-grade prostate cancers that had not yet been detected? Experts suspected that since smoking kills in different ways, some of those who pick up the habit simply may not live long enough to die from prostate cancer.

To investigate, the Austrian researchers limited their analysis to just over 22,000 men who had recently been treated surgically for prostate cancer, but were otherwise healthy. This was a smart move. By focusing on prostate cancer patients instead of just smokers and nonsmokers, they excluded the men who were at higher risk of death from competing causes.

After roughly six years of follow-up, the data told a clear story: prostate cancer patients who smoked were nearly twice as likely to die of their disease (89% higher risk) than nonsmokers. In addition, the risk that their cancers would spread was 151% higher, and there was a 40% higher risk that their prostate-specific antigen levels would rise again after surgery, signaling the cancer’s return.

The biological link between smoking and prostate cancer is not clear. The cancerous pollutants that smokers inhale are excreted to some extent in urine, which flows through the prostate. Smoking might boost levels of toxic inflammation. Or perhaps it’s not even the smoking itself, but the poor lifestyle choices that often accompany it, such as inadequate exercise, or excessive alcohol use..

“I continue to try to understand why some smoking patients are so concerned about simple modifications in diet and querying about supplements (most of which have never been proven to be of any benefit for prostate cancer patients) yet continue with their habit,” says Marc Garnick, the Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center, and editor in chief of “The message is clear – if you have prostate cancer and are concerned about how you can modify risk for cancer progression, and you are a smoker — simply STOP.”
The new cholesterol guidelines from the American College of Cardiology and American Heart Association are out! These guidelines — last updated in 2013 — have been highly anticipated by the cardiology and broader medical community. They have been approved by a variety of additional professional societies, including the American Diabetes Association. Thus, the majority of physicians are very likely to follow them. So, what exactly is new and what do you need to know?
It starts with a healthy lifestyle, with statins for those who need them

A healthy diet and regular physical activity are recommended for all age groups as the foundation to prevent cardiovascular disease (CVD) and CVD risk factors such as high cholesterol.

However, once there is atherosclerotic cardiovascular disease (plaque in the arteries), the new guidelines recommend that high-intensity statin therapy or maximally tolerated statin therapy should be used, in addition to lifestyle modification, to reduce low-density lipoprotein cholesterol (LDL-C). For example, this recommendation applies to patients with a history of prior cardiovascular events such as heart attacks, or of procedures such as stenting. The goal is to lower LDL-C levels by 50% or more.
Cholesterol targets are back!

Much to the delight of physicians, concrete LDL-C targets have been reintroduced into this version of the guidelines. For individuals with atherosclerotic cardiovascular disease who are at very high risk of cardiac complications, drug therapy beyond statins is recommended to achieve a target LDL-C of 70 mg/dl.

The first addition beyond high-intensity statins would be the now generic ezetimibe, a cholesterol-lowering drug that works by preventing the absorption of cholesterol in the intestine. If that does not do the trick, the injectable PCSK9 inhibitors are considered a reasonable next step, with the caveat that the drugs are expensive and their long-term safety beyond three years is not well established. However, since the guidelines were finalized, one of the two companies that makes PCSK9 inhibitors has lowered the list price. This may ultimately help make these potent cholesterol reducing drugs more cost-effective.

The same algorithm as above is recommended for otherwise healthy people whose LDL-C is greater than or equal to 190 mg/dL. In this case, however, the target is 100 mg/dL instead of 70 mg/dL, presumably because there is no evidence (yet) of actual atherosclerosis.

In people 40 to 75 years of age with diabetes who have an LDL-C greater than or equal to 70 mg/dL, a moderate-intensity statin is recommended. If there are additional risk factors or the person is 50 years or older, then a high-intensity statin is considered reasonable.

The above recommendations are not controversial among expert physicians in the field. In fact, some may say that these guidelines are not aggressive enough in terms of wanting lower cholesterol targets in very high risk patients. But none who understand the data would disagree with the above guidelines as general starting points. If you have atherosclerotic cardiovascular disease, a very high cholesterol level, or diabetes, then, in addition to a healthy lifestyle, you really ought to be on a statin, assuming you can tolerate it, and maybe additional medications, depending on your cholesterol level.
What about healthy people with moderately elevated cholesterol levels?

What about healthy people who don’t fit into the above categories? The guidelines provide clear guidance, but things do get a bit more nuanced. Here, there really needs to be a discussion between the patient and their doctor.

Whether to start a statin or not depends on whether there are other cardiovascular risk factors, such as smoking, high blood pressure, or diabetes, and the actual LDL-C level. A family history of premature atherosclerotic cardiovascular disease would be another factor to consider, as might South Asian ethnicity or premature menopause (before age 40). Other blood test abnormalities, such as elevated triglycerides or elevated high-sensitivity C-reactive protein levels (a marker of inflammation), might also push towards starting someone on a statin. Another recommendation in the new guidelines is for potential use of coronary artery calcium (CAC) scans to decide whether or not to initiate statin therapy in select cases where the decision based on clinical risk factors is unclear. Patient preferences and cost (though most statins are now generic) are other potential issues to weigh. Online risk calculators may help.

Bottom line: If you are one of the large number of people who fall into this category, talk to your doctor about whether you should be on medications to lower your cholesterol, or whether lifestyle changes are enough.

No comments:

Leave a comment