For the last four decades Americans have been told that cholesterol was our enemy. Eggs were bad because the yolks contained cholesterol. Lowering cholesterol was supposed to prevent heart attacks and strokes and prolong life. The idea that cholesterol could go too low seemed preposterous. What if there are risks associated with low cholesterol that you have not been told about?
Q. I am a 70 year old woman. My cholesterol has always been between 206 and 220 with high HDLs and a good ratio. Last summer, my doctor said 214 is no longer acceptable and put me on simvastatin. My HDL was 65.
My cholesterol has now dropped to 145. Since I’ve read that low cholesterol may be linked to strokes I am concerned. My mother died of a massive stroke and my father of a cerebral hemorrhage.
My weight and blood pressure are normal and I exercise daily. When I see my doctor again, should I question the need for simvastatin?
A. Low cholesterol has been linked with bleeding strokes. Scientists hypothesize that cholesterol helps strengthen the small arteries that feed the brain. Without it, they become more vulnerable to breakage under stress, which happens when blood pressure rises. That might help explain research findings showing that very low cholesterol poses problems too.
An article in the journal Stroke (Aug. 2013) points out that:
“Low cholesterol levels have been thought to decrease vessel resistance to rupture, as cholesterol is essential for normal membrane fluidity.”
These same researchers found that overall mortality was increased “in patients with lower total cholesterol and LDL levels…”
Is There Evidence that Low Cholesterol Poses a Problem?
Evidence comes from the Honolulu Heart Program. Scientists at the University of Hawaii studied 3,500 Japanese-American men born between 1900 and 1919. The volunteers’ total cholesterol levels were measured when they were middle-aged and again in the early 1990s, when they were elderly. Then the scientists kept tabs on who survived and who died.
To their surprise, the men with the lowest cholesterol levels had the highest risk of dying over the next several years. Those with cholesterol levels between 188 and 209 fared the best. Even men with elevated cholesterol, over 209, were less likely to die from any cause than were those with the lowest cholesterol readings. The investigators confessed their confusion:
“We have been unable to explain our results. These data cast doubt on the scientific justification for lowering cholesterol to very low concentrations (less than 4.65 millimoles per liter) [less than 180 milligrams per deciliter] in elderly people.”
I. J. Schatzt and colleagues wrote in The Lancet in 2001:
“Our data accord with previous findings of increased mortality in elderly people with low serum cholesterol, and show that long-term persistence of low cholesterol concentration actually increases the risk of death. Thus, the earlier that patients start to have lower cholesterol concentrations, the greater the risk of death.”
In July, 2011 an article in the journal Stroke noted that:
“Lower serum LDL-C [cholesterol] level independently predicts HG [hematoma growth], early neurological deterioration, and 3-month mortality after acute ICH [intracerebral hemorrhage or stroke].”
Are Women Especially Vulnerable?
This may be especially true for older women. With your family history of bleeding strokes, you should certainly discuss this issue with your physician. Your ratio of total cholesterol to good HDL cholesterol was great even before you started on simvastatin. Many experts now believe that this ratio is more important than cholesterol levels alone.
If you have no symptoms of heart disease you may want to ask your doctor why he is so gung ho about getting your cholesterol levels so low. There are no data to show that a woman of your age will benefit from statins in the primary prevention of heart disease. Someone who has had a heart attack or has been clearly diagnosed with heart disease may need such drugs. That is not obvious in your case from what you have described.
Although it often comes as a shock to physicians and patients, there are actually data to suggest that low cholesterol is associated with worse outcomes in older women. European researchers have discovered that elderly women have the lowest risk of death when their cholesterol levels are around 270.
- Forette, Bernard, et al. “Cholesterol as Risk Factor for Mortality in Elderly Women.” Lancet 1989; 1:868-870.
- Isles, C. G., et al. “Plasma Cholesterol, Coronary Heart Disease and Cancer in the Renfrew and Paisley Survey.” Br. Med. J. 1989; 298:920-924.
- Editorial. “Low Cholesterol and Increased Risk.” Lancet 1989; 298:920-924.
To learn more about risk factors and heart disease beyond cholesterol and a variety of other ways to improve your chances of living a long and healthy life we suggest our book, Best Choices From The People’s Pharmacy. It deals with the pros and cons of many cholesterol-lowering drugs and offers non-drug approaches you may find worthwhile.
Here is a link to our publications.