Inflammatory Bowel Disease May Raise Likelihood of Heart Attack

Increasingly, research has shown that inflammation within the body as a whole may elevate the risk for heart disease. A new study supports this premise, finding that individuals with the two main types of inflammatory bowel disease (IBD) — Crohn’s disease or ulcertative colitis — have significantly greater odds of having a heart attack compared with those without an IBD.

Crohn’s and colitis are both recurring inflammatory conditions; Crohn’s can affect any part of the gastrointestinal tract while ulcerative colitis is limited to the colon, or large intestine. IBDs affect as many as 1.6 million Americans, according to the Crohn’s and Colitis Foundation.

The report, published in November 2018 in the journal Inflammatory Bowel Disease, noted that a higher likelihood of heart attack among those with IBD persisted even after statistically adjusting for traditional cardiovascular risk factors, such as age, high blood pressure, diabetes, smoking, and high cholesterol.

“IBD should be recognized as an independent risk factor for the development of heart disease, and patients with IBD should be aggressively screened, have their cardiovascular risk factors modified, and have any symptoms of heart attack appropriately investigated by a physician,” says Mahazarin Ginwalla, MD, lead author of the study and director of heart failure with the Harrington Heart and Vascular Institute at University Hospitals Cleveland Medical Center in Ohio.

She says that modifiable risk factors include getting regular exercise, losing weight if obese, and stopping smoking. She further advises that patients with diabetes, hypertension, and high cholesterol should see their physicians regularly to control their levels.

Dr. Ginwalla and her coauthors reviewed five years of medical records from a huge database of 29 million adult patients from 26 nationwide healthcare systems. A total of 158,750 (0.55 percent) had Crohn’s Disease and 131,680 (0.45 percent) had ulcertative colitis.

The data revealed that those without an IBD had the lowest percentage of heart attacks (3 percent) while that percent was more than double among those with ulcerative colitis (6.7 percent) and Crohn’s (8.8 percent). After adjusting for age, race, sex, and traditional cardiovascular risk factors, IBD patients had a 25 percent greater likelihood of having a heart attack compared with the non-IBD patients.

Investigators remarked that the higher risk among Crohn’s patients may be due to the fact that Crohn’s is more aggressive and widespread than ulcerative colitis. “It is more likely associated with more intense inflammatory activation,” wrote study authors.

Based on previous research, the paper noted that the risk of adverse cardiovascular events may be highest during active flares or persistent disease, with this risk diminishing during times of remission.

How Inflammation May Play a Role

Other diseases involving inflammation, such as psoriasis, rheumatoid arthritis, and gum disease, also have been linked to cardiovascular disease.

“One theory is that the intense inflammation caused by these conditions may affect the blood vessels throughout the body, making them more vulnerable to blood clots,” says Sarah Samaan, MD, a cardiologist with Baylor Regional Medical Center in Plano, Texas, who wasn’t involved in the research.

“In a heart attack, cholesterol plaque becomes inflamed, and then a small segment of an inflamed plaque will typically rupture, causing the body to try to seal it off by forming a clot. It is this clot that is generally the cause of a heart attack, since it closes off blood flow to the heart artery, thus depriving the downstream muscle tissue of vital oxygen,” Samaan says.

Younger Patients Showed Higher Risk

For younger patients (ages 30 to 34), IBD was associated with 12 times increased risk of heart attack compared with those who did not have IBD. The risk declined with age. Heart attack odds were only twice as great in the IBD group of patients age 65 and above.

“This may be due to more aggressive and disabling disease with more frequent flare-ups in younger age groups implying higher levels of inflammation,” says Ginwalla.

She mentions that because lower numbers of younger patients were in the database, calculations of odds ratios may have been skewed. “However, this does not detract from the overall trend that was observed,” she says.

Study Limitations

Ginwalla, who conducted the investigations along with Muhammad Siyab Panhwar, MD, and Emad Mansoor, MD, says that although the study was very large, the database lacked granularity regarding the type of heart attack and did not allow for verifying the accuracy of the type of heart attack, the severity of disease, and the benefit of therapies for IBD.

Future prospective studies are needed to better understand the risk in the younger population of IBD patients and to explore the benefit of using anti-inflammatory drugs for the management of cardiovascular risk in patients with IBD, she says.