On the Road to Bariatric Success?

Blood clots a concern for obese people losing weight with surgery

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Bariatric surgery brings the benefit of extraordinary weight loss, but it also carries some health hazards. One risk is blood clots, which may be avoided through various methods, some more effective than others.

A new study suggested that medications commonly given to bariatric surgery patients may do a better job of preventing clots than filters inserted into the abdomen before the operation and designed to reduce clots.

"Ask your surgeon about the risks of bariatric surgery."

Daniel Brotman, MD, of Johns Hopkins Hospital and Johns Hopkins School of Medicine, was lead author of the study.

Based on his research team’s analysis of 13 previous studies – eight of which focused on drug regimens and five on filter placement – the scientists concluded that filters did not adequately cut clotting risks.

In fact, the researchers wrote, the filters raised clotting risks by roughly 1 percent. Filter placement also raised the studied patients’ risk of dying by about 4 percent.

The researchers wrote that they agreed with, among others, the American Society for Metabolic and Bariatric Surgery, which has "...declined to recommend any specific anti-[clotting medication] or filter placement strategy in bariatric surgery patients ... We found no evidence to support filter placement..."

Patients at greatest risk for blood clotting tended to get more intensive treatment, whether with the use of filters or higher doses of drugs traditionally used to treat clotting, researchers wrote.

In addition to reducing clotting more than filters, anti-clotting medications resulted in no deaths among certain groups of studied patients, regardless of whether the medication was dispensed at the normal or higher-than-normal dosages.

Because they often are extremely obese, candidates for bariatric surgery already suffer more than people of healthy weight from blood clots, which can limit their ability to get around physically, the researchers wrote. Clotting also has been associated with high blood pressure, diabetes and decreased blood circulation, especially in the legs, the researchers added.

Participants in the 13 analyzed studies generally were tracked for two to six weeks after surgery, though one study tracked them for more than two years.

Overall, the varying treatment choices for these bariatric patients, although aimed at curbing clotting risks, point to a lack of evidence-based, recommended guidelines in this area of medicine, researchers wrote.

Such a lack of standards may not result in the best patient outcomes. That reality is what prompted this study, researchers explained.

This study was published May 29 in the Journal of the American Medical Association Surgery.

The study was funded by the federal Agency for Healthcare Research and Quality, which also helped draft key questions and reviewed plans for data analyses, interim and final evidence reports. The agency, part of the US Department of Health and Human Services, was not involved in study selection, ratings, interpretation and compiling of the evidence, researchers wrote.

Reviewed by: 
Review Date: 
May 27, 2013
Last Updated:
August 8, 2013