Do TNF inhibitors affect hemoglobin A1c levels?
Debra Hughes writing in MPR reported on a study from the United Kingdom. Researchers asked the question, “Do tumor necrosis factor inhibitors (TNFi) improve HbA1c in patients with rheumatoid arthritis?” The answer depends on the agent and on whether patients have diabetes mellitus.
Some disease-modifying anti-rheumatic drugs (DMARDs)—including TNFis—may improve insulin resistance and risk of diabetes mellitus. “However, it is unknown whether TNFis improve HbA1c in patients with rheumatoid arthritis with or without diabetes mellitus,” they stated.
After adjusting for baseline HbA1c among patients without diabetes, those taking Humira had a significant increase in HbA1c levels between baseline and 12 months. In contrast, Enbrel therapy did not influence HbA1c levels over time.
Comment: Patients with RA who have diabetes need to be watched closely.