• Posted July 31, 2023

Belly Fat Can Hamper Effectiveness of Meds for Crohn's, Colitis

Some medications may not treat inflammatory bowel disease (IBD) as effectively if patients carry a lot of excess belly fat, , new research shows. IBD includes illnesses such as Crohn's disease and ulcerative colitis.

Researchers say using the wrong anti-inflammatory drug for these patients could mean lower rates of remission.

"Even though biologic medications have significantly improved outcomes for our patients with Crohn's disease or ulcerative colitis, some people do not respond well to these therapies," said Dr. Andres Yarur, a gastroenterologist at Cedars-Sinai in Los Angeles. "In our study, we found that the patients with higher amounts of internal abdominal fat were less likely to improve and experience remission from their disease."

Unlike some anti-inflammatory drugs, biologics work by blocking targets that cause inflammation in the body.

Researchers found that patients with higher levels of visceral fat had lower levels of the biologic medications in their blood after treatment and lower rates of steroid-free remission and bowel healing. Visceral fat is found deep within the abdomen, surrounding important organs, including the stomach, liver and bowels.

"It seems the fat tissue on the inner side of the abdomen, in particular, impacts treatment, so we may need to use higher doses of the drugs to help these patients," said researcher Dr. Gil Melmed, director of Inflammatory Bowel Disease Clinical Research at Cedars-Sinai.

For the study, the team treated 141 IBD patients with one of three biologic medications: infliximab (Remicade), ustekinumab (Stelara) or vedolizumab (Entyvio).

"We found that higher visceral adiposity was associated with higher levels of pro-inflammatory cytokines, suggesting that fat tissue promotes inflammation, the opposite of what we want, and increases resistance to biologic drug therapy," Melmed said, adding researchers don't know yet whether lowering visceral fat or giving higher doses of medication would improve drug effectiveness.

Yarur added that a different type of medication may be more effective in patients with high intra-abdominal visceral fat.

"We need to investigate drugs with different mechanisms of action, especially other small molecules, to see if our findings hold," he said, adding that as obesity and metabolic syndrome become more common, there is a need for alternatives to these biologic treatments for IBD.

The findings were published July 25 in the journal Gastroenterology.

More information

For more on inflammatory bowel disease, head to the U.S. Centers for Disease Control and Prevention.

SOURCE: Cedars-Sinai, news release, July 25, 2023