Researchers combined results from 10 studies examining whether SGLT2 inhibitors—medicines used by adults with type 2 diabetes—change hemoglobin and hematocrit, measures related to red blood cells. The studies included randomized and observational research and followed participants for 8 weeks to 24 months.

Across the randomized studies, the medicines were associated with higher hemoglobin and hematocrit than placebo. Real-world data also reported more cases classified as polycythemia, or an unusually high red-blood-cell level. The review found limited information about blood-clotting events and said larger, longer prospective studies are needed to clarify their significance.