Does metformin protect against osteoarthritis? An electronic health record cohort study

Prim Health Care Res Dev. 2017 Nov;18(6):623-628. doi: 10.1017/S1463423617000287. Epub 2017 May 25.

Abstract

Background: Obesity is a major risk factor for osteoarthritis (OA) whilst there is some evidence that diabetes also increases risk. Metformin is a common oral treatment for those with diabetes.

Objective: The aim is to investigate whether metformin reduces the risk of OA.

Methods: This was a cohort study set within the Consultations in Primary Care Archive, with 3217 patients with type 2 diabetes. Patients at 13 general practices with recorded type 2 diabetes in the baseline period (2002-2003) and no prior record of OA were identified. Exposure was a prescription for metformin. Outcome was an OA record during follow up. Cox proportional hazard models with Gamma frailty term were fitted: adjusted for age, gender, deprivation, and comorbidity.

Results: There was no association between prescribed metformin treatment at baseline and OA (adjusted HR: 1.02, 95% CI: 0.91, 1.15). A similar non- significant association was found when allowing exposure status of prescription of metformin to vary over time.

Keywords: cohort; osteoarthritis; survival analysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cohort Studies
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Electronic Health Records*
  • Female
  • Humans
  • Hypoglycemic Agents / pharmacology*
  • Longitudinal Studies
  • Male
  • Metformin / pharmacology*
  • Middle Aged
  • Osteoarthritis / complications
  • Osteoarthritis / prevention & control*

Substances

  • Hypoglycemic Agents
  • Metformin