Rheumatoid Arthritis Raises Heart Failure Risk
RA Patients Have Twice the Risk of Heart Failure, Study Shows
Feb. 3, 2005 -- Rheumatoid arthritis is a significant risk factor for heart
Researchers at the Mayo Clinic find that rheumatoid arthritis (RA) doubles
the risk of heart failure. Their report is in February's Arthritis &
In heart failure, the heart muscle doesn't pump as much blood as the body
needs. The heart still beats, but it's not working effectively. Many studies
have linked heart failure to chemicals related to inflammation. These
inflammatory chemicals are important in diseases such as RA, an autoimmune and
progressively chronic disease that is caused by an immune system malfunction,
which promotes inflammation.
After taking into account risk factors for heart failure, the researchers
wanted to see if RA promotes inflammation. They knew that heart problems have
been called an underlying cause of a "substantial proportion" of deaths
among RA patients.
Heart failure raises the risk of heart disease death by four- to 18-fold,
say Paulo Jorge Nicola, MD, and colleagues. They estimate that heart failure
strikes 2.4% to 5.5% of the general population over age 65.
In RA, joints become inflamed. Over time, the inflammation can damage the
joints, even causing disability. Imaging studies have indicated that people
with RA have signs of heart failure.
RA Doubled Heart Failure Risk
The researchers followed 575 rheumatoid arthritis patients and 583 people
without rheumatoid arthritis for 12-15 years. Researchers also examined their
medical records, starting when the participants were 18 years old.
Each RA patient was compared with a participant without RA of the same age
and gender. Most (73%) were women about 57 years old. In general, RA affects
women twice as often as men and usually starts between age 40 and 60.
At the start of the study no one had heart failure. But by the study's end,
heart failure had developed in 165 RA patients and 115 without RA. That's 34%
of the RA patients and 25% of those without RA.
After taking into account risk factors that can increase the risk of
developing heart failure, the study showed that RA was associated with almost
twice the risk of developing heart failure.
"We observed that patients with RA have twice the risk for the
development of congestive heart failure when compared to subjects without
RA," write the researchers.
Rheumatoid Factor's Effects
Participants were also screened for rheumatoid factor (RF). The blood test
measures levels of an antibody (RF) present in most RA patients.
RA patients whose blood had the RF antibody had the highest heart failure
risk. Compared with RA participants without RF, they were 2.6 times as likely
to develop heart failure. RA patients without the antibody were 1.3 times as
likely to develop heart failure.
Increased Risk Starts Early
RA patients were more vulnerable to heart failure almost right away, and the
danger deepened with time. "This increased risk may be present at the
earliest stages of the disease," say the researchers, urging doctors to be
aware of RA's heart failure risk.
The results held after adjusting for heart disease and related risk factors.
As an independent risk factor, RA might raise a patient's chance of developing
heart failure risk, even without other heart risk factors, say the
The reason for the higher risk isn't clear. It's probably not due to
medications, but that needs further study, say the researchers. They say the
risk didn't change between 1955 and 2001, when new RA treatments emerged.