SGLT2 Diabetes Drugs Show Surprising Arthritis Benefit
A large Korean study finds fewer autoimmune arthritis cases among SGLT2 inhibitor users compared with sulfonylureas
In a nationwide Korean study of over two million adults with type 2 diabetes, patients who started on SGLT2 inhibitors had a modestly lower risk of developing autoimmune rheumatic diseases especially inflammatory arthritis compared with those taking sulfonylureas.
Study Details:
Researchers from Sungkyunkwan University in Seoul analyzed data from South Korea’s National Health Insurance Database, covering 98% of the country’s population between 2012 and 2022. The study compared adults with type 2 diabetes who began treatment with either an SGLT2 inhibitor such as dapagliflozin (Farxiga), empagliflozin (Jardiance), or ertugliflozin (Steglatro) or a sulfonylurea.
Autoimmune rheumatic diseases were identified using national diagnosis codes, with subcategories for inflammatory arthritis (including rheumatoid, psoriatic, and spondyloarthritis) and connective tissue diseases (including lupus, Sjögren’s syndrome, and vasculitis).
Methodology:
Over a median follow-up of nine months, incidence rates were compared between the two treatment groups. Statistical adjustments accounted for comorbidities, other medications, clinical tests, and lifestyle factors.
Key Findings:
Weighted incidence rate of autoimmune rheumatic diseases:
SGLT2 inhibitors: 51.9 per 100,000 person-years
Sulfonylureas: 58.4 per 100,000 person-years
Hazard ratio: 0.89 (95% CI 0.81–0.98), indicating an 11% lower relative risk with SGLT2 inhibitors.
The reduced risk was mainly due to fewer cases of inflammatory arthritis (HR 0.86), not connective tissue diseases.
The benefit appeared greater in people with a BMI under 25 (HR 0.78).
Editorial commentary in The BMJ noted that this “intriguing finding” points toward possible immunomodulatory effects of SGLT2 inhibitors, which may shift macrophage behavior and reduce pro-inflammatory cytokine activity.
Implications for Practice:
While the absolute benefit is small more than 15,000 patients would need to be treated with SGLT2 inhibitors instead of sulfonylureas to prevent one autoimmune rheumatic disease per year the results add to growing evidence that SGLT2 inhibitors may have anti-inflammatory properties beyond glucose control.
For clinicians, this reinforces the broader metabolic and systemic benefits of SGLT2 inhibitors already known for heart and kidney protection. For patients, it’s a reminder that diabetes medications may influence immune and inflammatory health in subtle but meaningful ways.
Further studies are needed to confirm whether similar benefits extend to GLP-1 receptor agonists and to evaluate long-term effects across diverse populations.