Ask Dr. H: Ambien use and cardiac death risk

Question: Can you comment on a report that chronic Ambien users are three times more likely to die of a heart attack?

Answer: That's not exactly what the online-only British Medical Journal study reported. It reported that researchers compared the medical records of 10,529 people who received Ambien, Restoril, Lunesta, a sedating antihistamine like Benadryl, or some other sedative like Xanax for sleep with 23,676 who did not receive any sleeping pill over an average period of 21/2 years. There were 638 deaths among those who used a sleeping pill, compared with 295 deaths among those who did not.

On the surface, the findings of this retrospective medical records review are downright scary. But there are a number of methodological flaws in this study.

First, the reported cause of death was not identified. It's difficult to link the entire category of sedatives with an increased risk of death when the precise cause is not identified.

Second, the people who were taking sleeping pills had a significantly higher incidence of prior disease, including coronary artery disease, chronic kidney disease, asthma, and obesity, than those who were not. It appears that this study speaks more about the health of people who require sleeping pills than the inherent dangers of taking sleeping pills. Correlation and association do not necessarily equal cause.

While the study does give us a reason to reexamine the chronic use of sleep medication (especially in folks with serious underlying health problems), this study has enough flaws to let us sleep a bit easier at night.

nolead begins

Q: My husband suffered a stroke several months ago affecting his right side. His recovery has been slow, with only slight improvement in the use of his right arm and leg. What surprised me is that his neurologist said his stroke occurred on the left side of the brain. Can you explain?

A: One side of the brain controls the muscles of the opposite arm and leg. The motor nerve fibers that make arm and leg muscles move originate in the brain and cross to the opposite side of the body and run down the spinal cord. Why our bodies are designed this way is a mystery of human evolution.

The extent to which a stroke affects us depends upon its location and how much brain tissue was affected. If a stroke occurs in the right brain, the left side of the body (and the right side of the face) will be affected. Nerves that control facial muscles stay on the same side of the body and don't cross. Vision, memory, and personality changes may also result from a right-brain stroke.

Left-brain strokes affect the right side of the body (and the left side of the face). Speech and language problems like difficulty forming or saying the correct words may also result from a left-brain stroke. Memory loss may also follow a left-brain stroke.

A stroke involving the back part of the brain may result in vision and balance problems.

What are the major risk factors for stroke? High blood pressure; tobacco abuse (nicotine and other pollutants damage the blood vessels); a personal history of heart or vascular disease; a history of atrial fibrillation (a type of irregular heart rhythm); use of birth control pills along with smoking; excessive alcohol intake (women who average greater than 1 drink/day; men who average greater than 2 drinks/day); increasing age (stroke risk doubles for each decade of life after 55 due to arteries' becoming more calcified and brittle); obesity and sedentary lifestyles; and intravenous drug abuse (especially cocaine).