Stroke Archive

Studies showing that alcohol protects the heart raise questions about drinking.

Does moderate, prudent drinking protect the heart and arteries? Two analyses say — shout, actually — that the answer is yes. But they raise a bigger issue: What should we do with this information? The answer to that question may come as a surprise.

The carotid arteries carry oxygen-rich blood from the heart to the front half of the brain. But these crucial arteries can become narrowed by the cholesterol-laden plaques of atherosclerosis. Blood clots, or thrombi, can form on the plaques, then break off and travel as emboli to the brain, where they lodge in small arteries, interrupting the vital flow of blood to brain cells. If the interruption is partial or brief, the brain cells recover; the patient experiences a transient ischemic attack (TIA) with no permanent damage. But if the blockage is complete, brain cells die, producing a stroke.

In many cases, a TIA warns of a future stroke, giving doctors time to perform a carotid ultrasound test to see if the artery is mildly (less than 50%), moderately (50% to 69%), or severely (70% to 99%) narrowed. Once the diagnosis of carotid stenosis (narrowing) is established, several treatment options must be considered.

Niacin, also known as vitamin B₃ and nicotinic acid, is an essential nutrient. We need a small amount of it to ward off a disease called pellagra.

But like many vitamins these days, niacin has gotten more attention lately because of the benefits it might have when consumed in large amounts. Daily doses of 1,000 milligrams (mg) or more increase "good" HDL cholesterol and also reduce triglycerides. Many people, including quite a few doctors, view niacin as a useful, inexpensive — and perhaps more natural — way to bring about desirable cholesterol levels and reduce the risk of heart disease. Research going back to the early 1980s has shown that to be the case. Drug companies have sensed an opportunity and are selling products like Advicor (niacin plus lovastatin) and Simcor (niacin plus simvastatin) that combine high doses of HDL-raising niacin with statin drugs that lower "bad" LDL cholesterol.

Some people experience drops in blood pressure when they stand up. Falls are a risk. But there are often simple ways to counter the problem.

When we stand up, blood tends to pool in the lower half of our bodies, filling veins in the liver, intestines, and other abdominal organs, as well as those in the legs. The downward flow means there's a danger of not enough blood reaching the brain, which can lead to a loss of consciousness. But adjustments occur that keep that from happening. Sensors in the aorta in the torso and in the carotid arteries in the neck trigger a response that revs up the "fight-or-flight" part of the nervous system and dials down the "rest-and-digest" part. The heart beats a little faster and stronger. Blood vessels constrict, squeezing blood into a tighter space. Blood flow and blood pressure stay more or less normal.

Positive markers mean better heart health, less disease.

In 2010, the American Heart Association (AHA) added a new page to its playbook against the leading causes of death and disability in the United States. Instead of focusing solely on cardiovascular disease, the AHA is broadening its mission to include improving cardiovascular health.

It's a timely shift. The impressive decline in death rates from heart disease since 1970 is threatened by climbing rates of obesity and diabetes, the aging of the population, and early signs of heart disease in adolescents.

Aiming high is usually a good strategy for achieving a goal... except when it backfires. That's what happened with a large clinical trial dubbed AIM-HIGH. It was suddenly stopped more than a year ahead of schedule, casting a cloud over the use of niacin, a safe, effective medication with a proven track record for raising levels of protective high-density lipoprotein (HDL).

AIM-HIGH was designed to gauge whether adding a prescription form of niacin (Niaspan) to a cholesterol-lowering statin makes sense for people with low HDL. This combination had been tested in earlier trials, all of which showed a benefit. The big difference in AIM-HIGH was the very low target for low-density lipoprotein (LDL, the so-called bad cholesterol): between 40 and 80 milligrams per deciliter (mg/dL).

You don't have to be a brain surgeon to know it is vitally important for your brain to receive an uninterrupted supply of blood. That's because nerve cells require a constant supply of oxygen. Even a brief disruption stuns nerve cells, impairing their function, while more prolonged oxygen deprivation kills the cells. If only a small, noncritical area of your brain is affected, you may not notice the damage. Unfortunately, however, the damage is often very noticeable indeed. Brief or partial interruptions of blood flow cause transient ischemic attacks (TIAs), while prolonged or complete blockages are the major cause of cerebrovascular accidents — strokes.

Shocking statistics

Stroke is the fourth leading cause of death in the United States, taking about 136,000 lives annually. Another 660,000 Americans survive strokes each year, but many are so disabled that they cannot return to work. In human terms, it's an enormous burden of suffering; in dollar terms, it costs $74 billion a year to care for stroke victims and make up for their lost productivity.

Millions of women and men take calcium pills to strengthen their bones and ward off osteoporosis. Whether taking calcium is good, neutral, or bad for the heart is a matter of conflicting studies and lively debate. Australian researchers have sounded another note of caution in a controversial paper they published in the medical journal BMJ.

The Australian team took a fresh look at data from the Women's Health Initiative Calcium–Vitamin D Supplementation Study. It randomized 36,282 women to a calcium–vitamin D supplement or to a placebo. The results of the trial, published in 2006, showed a small improvement in hip bone density but no effect on hip fracture. The researchers reported that the numbers of heart attacks and other cardiovascular problems were the same in both groups.

Each year, the National Center for Health Statistics publishes a report card of sorts on the nation's health. Health, United States is chock full of graphs, charts, tables, and analysis. The latest edition includes a section on the use of statins, the family of cholesterol-lowering drugs we often mention. (First introduced in the late 1980s, seven statins are currently on the market, including Crestor, Lipitor, and Zocor.) One in four adults ages 45 and older now takes a statin. Data from another chart suggest that statins are contributing to the decline in Americans with high cholesterol.

Statins don't work miracles, and in some people cause muscle pain and other unwanted side effects. Diet and exercise are the first and best places to start if you need to lower the amount of harmful low-density lipoprotein (LDL) in your bloodstream. If they don't work, a statin or other cholesterol-lowering medication can help.

If you are having a stroke, a stroke center may be the place to go.

When talking about stroke, doctors often say that "time is brain." The faster you get medical help, the greater the chances of surviving and recovering from a stroke. A movement to establish special stroke centers across the country is ushering in a seemingly contradictory phrase: the old real estate adage "location, location, location." The rise of stroke centers means that emergency medical crews could bypass a nearby hospital and take a few extra minutes to reach a more distant one.