The retrospective cohort study from Taiwan investigated the development of Sjögren's syndrome in over 15,000 patients with type 2 diabetes who were on metformin. In a comparable control group, no metformin was administered. This group was also screened for the development of Sjögren's syndrome. The study duration covered 12 years. Patients already suffering from Sjögren's syndrome were excluded from the study.
Well, at least almost. The study showed that those diabetics who were prescribed metformin were significantly less likely to develop Sjögren's syndrome compared to the control group. In the metformin group, the incidence rate for Sjögren's syndrome was 16.82 per 100,000 patient-years while in the control group it was 40.83 per 100,000 patient-years. Furthermore, the researchers note that longer-term therapy with metformin (90 days or more) and a lifetime total dose of 45,000 mg or more of metformin also had a protective effect against Sjögren's syndrome. The results were statistically significant with a p-value of <0.05.
In recent years, metformin has increasingly become the focus of research. The drug has been used for various rheumatological and autoimmune diseases. The present study now shows that the drug might offer protection against Sjögren's syndrome through its effect on T helper cells and regulatory T cells while also reducing inflammatory reactions in the salivary glands through its effect on Interleukin 6 receptors.
Metformin may play a major role in reducing the probability of Sjögren's syndrome and possibly even in the treatment of the disease. However, further research is necessary to corroborate the results of this major study.
Source:
Wang CY, Lai JN, Liu CH, Hu KC, Sheu KL, Wei JC. Metformin Use Was Associated With Reduced Risk of Incidental Sjögren's Syndrome in Patients With Type 2 Diabetes: A Population-Based Cohort Study. Front Med (Lausanne). 2022 Jan 12;8:796615.