Can Aspirin Prevent Esophageal Cancer?

The American Cancer Society estimates that nearly 14,000 new cases of esophageal cancer will be diagnosed in the United States in 2003, the vast majority of which will occur in men.  Unfortunately, nearly 13,000 Americans will die of this disease this year, as esophageal cancer generally spreads to other sites in the body before it is diagnosed.  In addition to male gender, risk factors for esophageal cancer include tobacco abuse, heavy alcohol consumption (and combined tobacco use and drinking, in particular), chronic gastroesophageal reflux disease, and advancing age.

In view of the seriousness of this disease, the prevention of esophageal cancer is of great importance.  In the current issue of the journal Gastroentereology is a review of research studies over the past 20 years that addressed the effects of aspirin on the incidence of esophageal cancer.  This review, using a statistical method known as meta-analysis, identified a protective effect against esophageal cancer with both continuous and intermittent use of aspirin.  The use of the aspirin-related class of drugs referred to as nonsteroidal anti-inflammatory drugs (NSAIDs) also appeared to confer protection against esophageal cancer.  Intermittent use of these medications resulted in an 18% reduction in esophageal cancer risk, while regular or frequent intake of aspirin or NSAIDs reduced the risk of esophagus cancer by 46%,  An important observation was that aspirin and NSAIDs appeared to protect against the development of both of the predominant types of esophageal cancer (squamous cell carcinoma and adenocarcinoma).  The protective effects of these drugs were, in turn, proportional to the frequency of their use. 

This intriguing study offers encouraging evidence of an effective means of preventing a very dismal disease.  Of course, abstaining from tobacco and excessive alcohol intake are important preventive measures as well.  One bit of caution here:  check with your doctor before adding aspirin or NSAIDs to your daily medication intake, as these drugs are all associated with an increased risk of gastrointestinal bleeding and kidney disease.

The Impact of Obesity on Lifespan

By now, almost everyone knows that Americans face a virtual epidemic of obesity.  Most of us also know that this condition is associated with an increase in the risk of high blood pressure, cardiovascular disease, diabetes, and premature death.  A new study in the current issue of the Journal of the American Medical Association looks at the association between various levels of obesity and lifespan.  The study’s authors used government databases to correlate age at death with a measure of obesity known as body mass index (BMI).  The authors then compared average age at death for various degrees of obesity. 

The study identified significant differences in obesity-related premature death across both gender and ethnic lines.  Interestingly, younger obese adults appeared to experience a greater shortening of their overall lifespans than people who developed obesity later in life.  White males between the ages of 20 and 30 experienced a lifespan reduction of 13 years if they were in the severe obesity BMI range, while young Caucasian women with severe obesity experienced an average loss of 8 years.  Based upon these findings, severe obesity may result in the loss of more than 20% of predicted lifespan for white males.  Among black men and black women older than 60, moderate obesity was not associated with a significant decrease in lifespan.  However, severe obesity in younger African Americans was associated with an average lifespan reduction of 20 years for men and 5 years for women.

In summary, this study suggests that obesity, particularly during young adulthood, is associated with a significant decrease in lifespan, especially for males.  Based upon this study, it is perhaps even more important that younger adults, as opposed to middle-agers, adhere to that most common of New Year’s resolutions.  Indeed, this study strongly suggests that the presence of severe obesity during early adulthood poses a greater threat of eventual obesity-related mortality than does the onset of obesity much later in life.

In a related study, published in the current issue of the Annals of Internal Medicine, life expectancy rates for overweight and obese participants in a large long-term study of heart disease trends were evaluated.  Approximately 3,500 participants in the renowned Framingham Heart study were assessed between 1948 and 1990 in this study.  Overweight men and women who were 40 years old at the onset of the study lost an average of about 3 years of lifespan when compared to men and women of normal weight.  Men who were frankly obese at age 40 lost almost 6 years of lifespan, while women who were obese at age 40 lost about 7 years of lifespan.  Obese men and women who also smoked fared even worse.  When compared to the statistical impact of smoking on lifespan, significant obesity during early adulthood was found to cause comparable reductions in lifespan as did tobacco abuse. 

Both of these studies indicate that significant obesity during early adulthood substantially increases the risk of premature death later in life.  Eat less, exercise more… live longer.

Hormones & Breast Cancer

The incidence of breast cancer increased approximately 0.5% per year between 1987 and 1998.  The cause—or causes—for this sustained increase in breast cancer cases has been the subject of a great deal of debate.  In the current issue of the Journal of Clinical Oncology is a report that sheds additional light on this worrisome trend.  The authors used the National Cancer Institute’s annual cancer statistical summary to study breast cancer trends between 1992 and 1998.  They specifically looked at the differences in breast cancer estrogen receptor (ER) and progesterone receptor (PR) status.  The expression of these sex hormone receptors on breast cancer cells is associated with a generally more favorable prognosis than breast cancers which lack these receptors.  The ER and PR status of breast cancer tumors may also say something about the mechanisms involved in breast cancer development, as different cancer development pathways may be involved for tumors as a function of their hormone receptor status.

The study determined that the percentage of breast cancers containing ER and/or PR increased during the study period.  At the same time, the overall incidence of breast cancers that did not express ER and PR remained steady.  The authors, therefore, conclude that the increase in breast cancer incidence during the study period arose primarily due to an increase in tumors that were positive for ER and/or PR.  As hormonal factors are thought to play a relatively greater role in ER-positive and PR-positive breast cancers, this study provides some evidence for a hormonal basis, at least in part, for the sustained increase in the incidence of breast cancer in the United States.

A Drink to Your Health!

Moderate alcohol intake has been shown to reduce the risk of cardiovascular disease and stroke, while heavy drinking is associated with an increased risk of liver disease, cancer and dementia.  A study in this week’s New England Journal of Medicine looked at the association between alcohol intake and the risk of cardiovascular disease.  More than 38,000 male health professionals participated in this study for an average off 12 years, and all study participants were free of cardiovascular disease and cancer at the beginning of the study.  Their consumption of beer, red wine, white wine and liquor was individually evaluated, and the incidence of heart attacks in this population was assessed.

Men who consumed alcohol 3-4 days per week experienced a 32% decrease in their risk of heart attack when compared to men who drank alcohol less than once per week.  Consumption of alcohol 4-5 times per week translated into a 36% reduction in the risk of heart attack, and alcohol consumption with meals was equally effective as alcohol consumed without food.  This benefit held up for all of the alcoholic beverages studied. 

This study offers strong evidence linking moderate alcohol intake with protection against cardiovascular disease, at least in males.  Remember, of course, to drink alcohol responsibly.

Dr. Robert A. Wascher