Jewish World Review Jan. 18, 2002 / 5 Shevat, 5762

Lifelong effects of premature birth

By Robert A. Wascher, M.D., F.A.C.S. -- This week's New England Journal of Medicine features a study of cognitive and academic outcomes in 242 adult survivors of premature birth. The average birth weight of these pre-term birth survivors was 1179 grams (2.6 pounds), and all were delivered following pregnancies averaging 29.7 weeks in length. The pre-term birth survivors were compared with 233 young adults of similar age and socioeconomic background, all of whom had normal birth weights.

This study's findings add to previous research that has linked very low birth weights to an elevated risk of cognitive and academic problems later in life. As compared with the normal birth weight group, the very low birth weight group graduated from high school less frequently, scored lower on standardized IQ and academic achievement tests, had a higher rate of neurosensory impairments, and were shorter in stature. Men in the pre-term birth group-but not women-were also less likely to enroll in college. At the same time, the pre-term birth group reported less alcohol and drug use, and had lower rates of pregnancy than the full-term birth group.

The effects of premature birth are not fully understood at this time. However, it has become reasonably clear that lifelong brain development can be adversely affected in babies with extremely low birth weights. Such babies are also at increased risk of developing brain hemorrhage and other complications at birth that can adversely impact on brain function and development, although this was not factored into this study's design or analysis.

While there is an increased risk of long-term complications in babies with very low birth weights, not all pre-term babies will experience delayed cognitive development, decreased academic potential, or short stature. Each child, whether born early or "on time," is a unique individual, and has a unique potential for development and accomplishment. However, very low birth weight babies may require careful monitoring and assistance, as they grow, in order to aid them in attaining their maximum cognitive and academic potential in life. SMOKERS UNDER THE KNIFE

As a surgeon, I am all too aware of the increased risk of complications that occurs in smokers undergoing surgery. An interesting study from Denmark in this week's Lancet looks at the impact of temporary smoking cessation on patients about to undergo hip or knee replacement surgery. Fifty-six patients agreed to quit smoking 6-8 weeks before surgery, and 52 active smokers volunteered to serve as controls in the study. The smoking cessation group received counseling and nicotine supplements, and was required to either abstain from smoking, or to reduce cigarette consumption by at least 50%.

Complications following surgery occurred in 18% of the patients in the tobacco abstinence group versus 52% of the patients in the group of active smokers. The most striking reductions in surgical complications among the tobacco-abstaining patients occurred in the categories of surgical wound and cardiovascular complications.

The results of this study confirm, once again, the significant health benefits that derive from even relatively short periods of tobacco abstinence. Quite apart from the disastrous health effects of tobacco that arise after many years of smoking (and chronic exposure to the more than 2,000 carcinogens and toxins discovered to date in tobacco smoke), the inhalation of tobacco smoke acutely impairs heart and blood vessel function, reduces lung capacity and blood oxygen levels, and increases the risk of abnormal blood clotting in blood vessels throughout the body. Each of these deleterious effects of tobacco is capable of causing serious complications in patients undergoing surgery, and sometimes with fatal results. ASPIRIN AND CARDIOVASCULAR HEALTH

Over one million American will experience a new or recurrent heart attack this year. The current issue of the Annals of Internal Medicine reviews the impact of aspirin on the development of heart disease and heart attack, based upon the recent findings of the U.S. Preventive Services Task Force (USPSTF).

The evidence to date suggests that aspirin can significantly reduce the risk of heart attacks, particularly in patients with multiple risk factors for heart disease (these include age 60, high total cholesterol or LDL cholesterol levels, low levels of HDL cholesterol, tobacco use, the presence of high blood pressure or diabetes, male gender, and a family history of cardiovascular disease). At the same time, aspirin is known to increase the risk of gastrointestinal bleeding and hemorrhagic strokes, particularly in people who are older.

The optimum dose of aspiring for cardiovascular disease prevention is not clear. However, it appears that as little as 75 mg of aspirin (a "baby aspirin" has 81 mg of aspirin) per day provides cardiovascular benefits comparable to a 325 mg adult aspirin tablet, while simultaneously reducing the risk of aspirin-induced complications (it should be noted that even "enterically-coated" aspirin tablets are known to cause these same complications).

In reviewing all studies to date, the USPSTF found that the use of daily aspirin reduced the risk of heart attack by about 28%. At the same time, aspirin increased the risk of gastrointestinal bleeding and, to a much lesser extent, the risk of hemorrhagic stroke (aspirin's beneficial effect on cardiovascular health is thought to be primarily due to its anti-clotting action on the blood).

Based upon this analysis, if one looks at 1,000 patients known to be at increased risk of heart attack, the daily use of aspirin over a five-year period would prevent 6 to 20 heart attacks, but would also cause 2 to 4 major gastrointestinal hemorrhages and 0 to 2 hemorrhagic strokes. In patients with a lesser risk of heart attack, aspirin's beneficial effects on heart attack risk decline, while the risk of aspirin-induced complications remains the same.

With this in mind, the USPSTF recommends that physicians carefully assess the cardiac disease risk of their patients, as well as their susceptibility to aspirin's adverse side effects, before recommending aspirin therapy. As it stands now, 1 or 2 baby aspirin tablets per day appear to provide the same cardiovascular health benefits as the 325 mg adult tablet, while somewhat reducing-but not eliminating-the risks of gastrointestinal bleeding and, possibly, hemorrhagic stroke. Bottom line: see your doctor before starting yourself on daily aspirin therapy!

JWR contributor Dr. Robert A. Wascher is a senior research fellow in molecular & surgical oncology at the John Wayne Cancer Institute in Santa Monica, CA. Comment by clicking here.


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© 2002, Dr. Robert A. Wascher