Association of Metformin with Susceptibility to COVID-19 in People with Type 2 Diabetes
Jingya Wang, Jennifer Cooper, Krishna Gokhale, Dionisio Acosta-Mena, Samir Dhalla, Nathan Byne, Joht Singh Chandan, Astha Anand, Kelvin Okoth, Anuradhaa Subramanian, Mansoor N. Bangash, Thomas Jackson, Dawit Zemedikun, Tom Taverner, Wasim Hanif, Sandip Ghosh, Parth Narendran, Konstantinos A. Toulis, Abd A. Tahrani, Rajendra Surenthirakumaran, Nicola J. Adderley, Shamil Haroon, Kamlesh Khunti, Christopher Sainsbury, G. Neil Thomas, Krishnarajah Nirantharakumar
Abstract
OBJECTIVE: Diabetes has emerged as an important risk factor for mortality from COVID-19. Metformin, the most commonly prescribed glucose-lowering agent, has been proposed to influence susceptibility to and outcomes of COVID-19 via multiple mechanisms. We investigated whether, in patients with diabetes, metformin is associated with susceptibility to COVID-19 and its outcomes. RESEARCH DESIGN AND METHODS: We performed a propensity score-matched cohort study with active comparators using a large UK primary care dataset. Adults with type 2 diabetes patients and a current prescription for metformin and other glucose-lowering agents (MF+) were compared to those with a current prescription for glucose-lowering agents that did not include metformin (MF-). Outcomes were confirmed COVID-19, suspected/confirmed COVID-19, and associated mortality. A negative control outcome analysis (back pain) was also performed. RESULTS: There were 29 558 and 10 271 patients in the MF+ and MF- groups, respectively, who met the inclusion criteria. In the propensity score-matched analysis, the adjusted hazard ratios for suspected/confirmed COVID-19, confirmed COVID-19, and COVID-19-related mortality were 0.85 (95% CI 0.67, 1.08), 0.80 (95% CI 0.49, 1.30), and 0.87 (95% CI 0.34, 2.20) respectively. The negative outcome control analysis did not suggest unobserved confounding. CONCLUSION: Current prescription of metformin was not associated with the risk of COVID-19 or COVID-19-related mortality. It is safe to continue prescribing metformin to improve glycemic control in patients with.