Obesity Epidemic

Ms. Farley is a freelance medical writer based in Wakefield, Rhode Island.

Obese Kids Battling Liver Disease

As the number of obese children increases, so does the number of liver disease cases in this young population. Nonalcoholic fatty liver disease (NAFLD), prevalent in more than 6 million US children, occurs when oily triglyceride droplets form in liver cells. NAFLD can lead to cirrhosis and liver failure and possibly a liver transplant. Other consequences include diabetes, high blood pressure, and high cholesterol—all linked to cardiovascular stress. In fact, the rise in obesity rates has made NAFLD the most chronic liver disease in children—occurring in 9% to 10% of US children. Research shows that approximately 5% of children with NAFLD will develop severe advanced liver disease.

The study, which appeared in Circulation's July 8, 2008, issue, included 150 overweight kids with NAFLD and 150 overweight kids without NAFLD, with an average age of 12. The group of overweight kids with NAFLD had higher levels of blood sugar, insulin, total cholesterol, low-density lipoprotein cholesterol, triglycerides, and blood pressure, as well as lower levels of high-density lipoprotein cholesterol. Researchers also note that kids with NAFLD will have darkening and thickening of the skin around the neck. In this study, more Hispanic and Asian children had NAFLD than white and black children. No current treatment for NAFLD is available other than making important lifestyle changes in diet and exercise.

Drug-Releasing Stents Helpful for Obese Patients

An unexpected research discovery has shown that being obese may provide patients with some protection during heart-related episodes such as heart attacks. Study data showed that obese patients with stents fared better than normal-weight patients when it came to adverse cardiac events. A German research team analyzed 1-year outcomes for 607 patients with coronary artery disease who were treated with sirolimus-releasing stents; the group included 176 normal-weight patients, 289 overweight patients, and 146 obese patients.

Cardiac events considered in this study included death, heart attack, stroke, repeat angioplasty, or other revascularization.

Although a larger randomized study is needed to confirm or refute these claims, these results show an obvious difference in the benefits of sirolimusreleasing stents in the obese/overweight population. The study can be found in the June 2008 issue of the American Journal of Cardiology.

Fight Metabolic Syndrome with Intense Workouts

Metabolic syndrome—that cluster of symptoms plaguing so many Americans—may possibly be reversed with the help of intense aerobic interval training, according to a small study.

The recipe for metabolic syndrome includes:

• High blood pressure
• High blood glucose levels
• High triglyceride levels
• A large waist circumference
• Low high-density lipoprotein cholesterol

Results of the European study showed that when patients with all the symptoms of metabolic syndrome performed aerobic interval training at 90% of the highest measured heart rate several times a week, they reduced 1.9 factors for metabolic syndrome. When training was performed at only 70% of the maximum heart rate, 0.7 risk factors were reduced. The 32 study participants performed either aerobic interval training or continuous moderate exercise 3 times a week for 16 weeks, or they were in the control group. Besides decreasing their risk factors, participants in the interval training group also increased their maximal oxygen uptake greater than those in the moderate exercise group. No significant differences were found between the 2 exercise groups in terms of reduced blood pressure, body weight, and fat. Lead study author Arnt Erik Tjonna of the Norwegian University of Science and Technology suggests that "exercise in general and aerobic interval training in particular is partly or fully able to reverse metabolic syndrome, suggesting that this may be a promising treatment strategy." Further study information appears in the July 7, 2008, rapid access issue of Circulation.

Prostate Cancer Screening Results Altered by Obesity

The usual screening test for prostate cancer may yield inaccurate results when it comes to obese men. Researchers found that obese men who are screened for prostate cancer have low levels of prostate-specific antigen (PSA), even in the presence of prostate abnormalities. Researchers suggest that, because obese men have excess blood volume, the PSA values may be diluted. Typically, when a man has prostate cancer, PSA levels are higher, and this is detected in the PSA screening; those with high PSA levels receive further testing. The concern is that, in obese men, some cancers are not being detected promptly enough or at all. The researchers suggest adjusting the PSA value in the cases of obese men to take into account the diluted PSA measurements.