Gout risk in adults with pre-diabetes initiating metformin

• Published in: Annals of the rheumatic diseases Vol. 83; no. 10; p. 1368
• Main Authors: Marrugo, Javier, Santacroce, Leah M, Paudel, Misti L, Fukui, Sho, Turchin, Alexander, Tedeschi, Sara K, Solomon, Daniel H
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group LTD 30.09.2024
• Subjects: Adult; Aged; Antidiabetics; Body mass index; C-reactive protein; C-Reactive Protein - analysis; Codes; Cohort Studies; Cytokines; Diabetes; Diabetes mellitus; Diuretics; Electronic medical records; Female; Glycated Hemoglobin - analysis; Gout; Gout - blood; Gout - drug therapy; Gout - epidemiology; Hemoglobin; Hospitals; Humans; Hypertension; Hypoglycemic Agents - administration & dosage; Hypoglycemic Agents - therapeutic use; Incidence; Kidney diseases; Male; Metformin; Metformin - administration & dosage; Metformin - therapeutic use; Middle Aged; Pathophysiology; Prediabetic State - epidemiology; Propensity Score; Proportional Hazards Models; Rheumatism; Risk Factors; Uric acid; Uric Acid - blood; User groups; United States > US; Massachusetts; Gout; Crystal arthropathies; Incidence
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/ard-2024-225652

Despite the strong association between gout and pre-diabetes, the role of metformin in gout among individuals with pre-diabetes remains uncertain. We compared the incidence rates of gout in adults with pre-diabetes starting metformin with those not using antidiabetic treatments. We conducted a new-user, propensity score-matched cohort study using electronic health records from an academic health system (2007-2022). Pre-diabetes was defined based on haemoglobin A1c levels. Metformin users were identified and followed from the first metformin prescription date. Non-users of antidiabetic medications were matched to metformin users based on propensity score and the start of follow-up. The primary outcome was incident gout. Cox proportional hazards models estimated the HR for metformin. Linear regression analyses assessed the association between metformin use and changes in serum urate (SU) or C-reactive protein (CRP). We identified 25 064 individuals with pre-diabetes and propensity score-matched 1154 metformin initiators to 13 877 non-users. Baseline characteristics were well balanced (all standardised mean differences <0.1). The median follow-up was 3.9 years. The incidence rate of gout per 1000 person-years was lower in metformin users 7.1 (95% CI 5.1 to 10) compared with non-users 9.5 (95% CI 8.8 to 10.2). Metformin initiation was associated with a reduced relative risk of gout (HR 0.68, 95% CI 0.48 to 0.96). No relationship was found between metformin and changes in SU or CRP. Metformin use was associated with a reduced risk of gout among adults with pre-diabetes, suggesting that metformin may be important in lowering gout risk in individuals with pre-diabetes.