What Aspirin Might Do for Obese Patients

Aspirin use tied to reduced colorectal cancer risk in obese patients with Lynch syndrome

(RxWiki News) Being obese can put patients at greater risk for many conditions, including some types of cancer. But for some, taking a common over-the-counter medication may reduce this increased risk.

A new study found that regular use of aspirin was tied to a reduced cancer risk among obese people with a genetic predisposition to colorectal cancer.

"The lesson for all of us is that everyone should try to maintain a healthy weight and for those already obese the best thing is to lose weight. However, for many patients this can be very difficult so a simple aspirin may be able to help this group," said lead study author John C. Mathers, PhD, of Newcastle University in the United Kingdom, in a news release.

Dr. Mathers and colleagues' study focused on adults with Lynch syndrome, a hereditary condition that increases the risk for cancers of the colon and rectum, called colorectal cancer.

A total of 937 patients with Lynch syndrome were enrolled in this study. Half of these patients took 600 milligrams of aspirin per day for an average of two years. The other half received a placebo, or inactive medicine replacement. These patients came from 43 health centers in 16 countries. They were 45 years old on average.

The patients' weight status was assessed using body mass index (BMI), a ratio of weight to height. The patients were followed for an average of 4.5 years. Some were followed for as long as 10 years.

During the follow-up period, a total of 55 patients were diagnosed with colorectal cancer. Overall, the obese patients were 2.31 times as likely as normal-weight patients to develop this kind of cancer.

"For those with Lynch syndrome, we found that every unit of BMI above what is considered healthy increased the risk of bowel cancer by 7 percent," Dr. Mathers said. "What is surprising is that even in people with a genetic predisposition for cancer, obesity is also a driver of the disease. Indeed, the obesity-associated risk was twice as great for people with Lynch syndrome as for the general population."

However, this increased risk for the obese was only seen in the placebo group — not among those who were taking aspirin.

"This is important for people with Lynch syndrome but affects the rest of us too," said study co-author Sir John Burn, MD, also of Newcastle University, in a news release. "Lots of people struggle with their weight and this suggests the extra cancer risk can be cancelled by taking an aspirin."

However, Dr. Burn added, "Before anyone begins to take aspirin on a regular basis they should consult their doctor as aspirin is known to bring with it a risk of stomach complaints including ulcers."

Further research is needed to understand how cancer risk in the obese and aspirin might be related — and to examine potential side effects.

This study was published online Aug. 17 in the Journal of Clinical Oncology.

A number of groups funded this research, such as Cancer Research UK, the European Union and Australia's Cancer Council Victoria. Bayer, a producer of aspirin, provided both the medications and placebos used, as well as donations to Newcastle University to cover costs tied to the study. Several study authors reported ties to pharmaceutical companies, including Bayer.


Review Date: 
August 17, 2015