Rheumatoid arthritis (RA) patients not only have approximately twice the risk of congestive heart failure (CHF) as their non-arthritis counterparts, 1 they are also at higher risk for unrecognized heart disease and much less likely to complain of angina pectoris,2 according to two retrospective, population-based cohort studies in the February issue of Arthritis & Rheumatism.

Taken together, these studies "should raise the index of suspicion for the rheumatologists who care for these patients and should also raise awareness for patients with RA to encourage them to pay closer attention to their cardiovascular health," Sherine E. Gabriel, MD, department chair of Health Sciences Research at the Mayo Clinic in Rochester, Minnesota, and corresponding author on both papers, tells CIAOMed.

RA and CHD Inextricably Linked

This increased risk was not explained by traditional risk factors for heart disease in either study, suggesting that something more disease-specific is at play. "These findings suggest that another factor is responsible for this excess risk [and] we suspect that the systemic inflammation that characterizes RA also promotes heart disease in persons with RA," Dr. Gabriel says.

In the study that tracked risk of coronary heart disease (CHD) in RA patients, those with RA were 3 times more likely to have been hospitalized for an acute heart attack and 5 times more likely to have an unrecognized heart attack during the 2 years before RA diagnosis. Moreover, RA patients were also less likely to have had a history of angina pectoris when compared with RA-free counterparts.

According to the new findings, the risk was higher among patients who were positive for rheumatoid factor than those who tested negative.

The CHF study population comprised 575 RA patients and 583 RA-free, age- and gender-matched controls. After 30 years of follow-up, the cumulative incidence of CHF was 34% in RA patients and 25% in non-RA subjects. The increased risk initiated soon after RA onset and continued throughout the disease, the study showed.

Culled from the Rochester Epidemiology Project, the RA patients were initially diagnosed between 1955 and 1995 and followed until death, heart failure, moving from Rochester, or January 1, 2001.

 

Commenting on this finding, Hayes Wilson, MD, chief of rheumatology at Piedmont Hospital in Atlanta, Georgia, and a national medical advisor to the Arthritis Foundation, also based in Atlanta, tells CIAOMed that "the general wisdom would be that our patients live in pain and learn to ignore pain and this may be to detriment when it comes to [angina]."

After the RA incidence date, RA patients were twice as likely to experience unrecognized myocardial infarction (MI) and sudden death and less likely to undergo coronary artery bypass grafting, compared with non-RA subjects. Controlling for the CHD risk factors did not substantially change the risk estimates, the researchers report.

This study comprised a population-based incidence cohort of 603 residents of Rochester, Minnesota, ages 18 years who first fulfilled the American College of Rheumatology (ACR) 1987 criteria for RA between January 1, 1955, and January 1, 1995, and 603 age- and sex-matched non-RA subjects. All subjects were followed up through their complete inpatient and outpatient medical records, beginning at age 18 years until death, migration, or January 1, 2001.

Researchers collected data on CHD events and diabetes mellitus, hypertension, dyslipidemia, body mass index, and smoking. CHD events included hospitalized MI, unrecognized MI, coronary revascularization procedures, angina pectoris, and sudden CHD deaths.

Rheumatologists Need High Index of Suspicion/Low Threshold for Evaluation

"We need a higher index of suspicion and lower threshold for evaluating and referring these patients to cardiologists," Dr. Wilson comments. "Every new study makes our sight a little clearer, but we have a lot more to learn about the increased risk of heart disease in RA patients," he adds.

"There are a lot of theories about CHD and lymphoma, which are over represented in patients with severe RA related to immune dysfunction," he observes. "I believe the systemic inflammation effect takes its toll on all organs of the body," he points out.

References:

1. Nicola PJ, Maradit-Kremers H, Roger VL. The risk of congestive heart failure in rheumatoid arthritis: a population-based study over 46 years. Arthritis Rheum. 2005;52:412-420.

2. Maradit-Kremers H, Crowsin CS, Nicola PJ, et al. Increased unrecognized coronary heart disease and sudden deaths in rheumatoid arthritis: a population-based cohort study. Arthritis Rheum. 2005;52:402-411.