Some Cholesterol Medications Affect Quality of Sleep

Lowering your cholesterol could interrupt your slumber.

A report presented at a recent American Heart Association meeting finds that the statin Zocor® disrupts sleep patterns in some users.

"The study suggests that simvastatin [Zocor] is more likely to have sleep disruption," says Dr. Sidney Smith, director of the Center for Cardiovascular Science and Medicine at the University of North Carolina School of Medicine.

"The extent to which this would be a significant problem for patients is uncertain, but this should raise awareness that symptoms could be related to therapy," says Dr. Smith.

The major effect of the statins is to lower LDL-cholesterol levels, and they lower LDL-cholesterol more than other types of medications, according to the National Institutes of Health (NIH).

Low-density lipoprotein (LDL) cholesterol is commonly called the "bad" cholesterol. It is a type of fat in the blood that contains the most cholesterol. It can contribute to the formation of plaque buildup in the arteries, known as atherosclerosis.

Statins inhibit an enzyme that controls the rate of cholesterol production in the body. These medications lower cholesterol by slowing down the production of cholesterol and by increasing the liver's ability to remove the LDL-cholesterol already in the blood.

Fat-Soluble Statins Affect Brain

A growing number of Americans now take statins to reduce their cholesterol levels, as a way to prevent heart attack or stroke.

"There had long been concerns about statins adversely affecting sleep in case reports and case series dating back to at least 1990, just after the release of statins," says Dr. Beatrice Golomb, of the University of California, San Diego.

"The rub is that they used sample sizes that were tiny and follow-ups of only four to six weeks. The sample sizes were less than 20 or 30 - not enough typically to show an effect unless the effect was huge," notes Dr. Golomb.

The study is the largest of its kind and involved 1,106 healthy adult men and women who were randomly chosen to receive 20 milligrams of Zocor (simvastatin), 40 milligrams of Pravachol® (pravastatin), or a placebo (an inactive substance) for six months.

The two dosages of the two statins are considered approximately equivalent.

"We were looking at the impact of the most hydrophilic [Pravachol] and most lipophilic [Zocor] statins on a range of non-cardiac endpoints with sleep as a pre-specified secondary outcome," says Dr. Golomb.

Lipophilic means the medication is soluble in fat, while hydrophilic means it is soluble in water.

Previous research had implicated fat-soluble statins in sleep disturbances.

"Simvastatin is fat-soluble, and can penetrate and cross into the brain," explains Dr. Smith.

Dr. Golomb says: "We did show significant worsening in both sleep quality outcome and sleep problem categories in patients taking simvastatin. Less sleep quality and more sleep problems."

Those participants who had worse sleep also showed a worsening in their aggression scores, compared to persons in the other two study groups.

Heart Protection Outweighs Sleep Needs

This does not mean that patients experiencing sleep problems should take themselves off Zocor or another statin, says Dr. Smith.

"The broader benefit of decreasing heart attack and stroke must be taken into account," he says.

And patients who find themselves truly sleep-deprived can also talk to their physician about finding an alternate statin, he concludes.

Always consult your physician for more information.