Photo: Getty Images
Low folate levels are associated with an increased risk of heart disease death in patients with rheumatoid arthritis, or RA, a new study suggests.
People with RA have a 60 percent increased risk of dying from heart disease, but the reasons have been unclear.
"Our study is the first to show an association between serum folate and increased cardiovascular mortality in patients with rheumatoid arthritis," lead author Kalyani Sonawane said in a University of Texas news release. She is an assistant professor at UTHealth's School of Public Health.
This study included 683 RA patients who were divided into three groups based on their blood levels of folate, a B vitamin also known as folic acid.
One group had levels below 4.3 nanograms per milliliter, the second group had levels between 4.3 and 8.2 nanograms per milliliter, and the third group had levels greater than 8.2 nanograms per milliliter.
Over 17 years, 258 of the participants died of heart disease. A folate level below 4.3 nanograms per milliliter was associated with 50 percent higher risk of death from heart disease, according to the study.
"Our findings suggest that serum folate level might be a useful indicator to assess [the] cardiovascular mortality risk of a rheumatoid arthritis patient in clinical practice," said study senior author Dr. Maria Suarez-Almazor, a professor in the University of Texas MD Anderson Cancer Center. But the study did not prove that low folate levels cause heart risks to rise.
"If future clinical studies validate a causal link, taking folate supplements could be an affordable way to reduce this risk in patients with rheumatoid arthritis," Suarez-Almazor said in the release.
Folate is essential in the creation of new cells and lowers levels of homocysteine, an amino acid found in blood. High homocysteine levels have been linked to an increased risk of heart disease.
Many people with RA have elevated homocysteine levels. This may be due to medications prescribed for rheumatoid arthritis, such as methotrexate, which decrease folate levels, the researchers explained.
"It's particularly important for patients taking disease-modifying anti-rheumatic drugs to understand this increased risk," Sonawane noted.
Folic acid is found in many foods such as eggs, broccoli, citrus fruits, and leafy greens. Supplements can also be taken to boost folate levels. The study was published Feb. 26 in the journal JAMA Network Open.