Contraindications to metformin therapy in patients with Type 2 diabetes--a population-based study of adherence to prescribing guidelines

Diabet Med. 2001 Jun;18(6):483-8. doi: 10.1046/j.1464-5491.2001.00509.x.

Abstract

Aims: To define the number of people in Tayside, Scotland (population 349 303) with Type 2 diabetes who use metformin, the incidence of contraindications to its continued use in these people and the proportion that discontinued metformin treatment following the development of a contraindication.

Methods: Retrospective cohort study of the incidence of contraindications to metformin in all patients with Type 2 diabetes using metformin from January 1993 to June 1995. The contraindications of acute myocardial infarction, cardiac failure, renal impairment and chronic liver disease were identified by: the regional diabetes information system, biochemistry database and hospital admissions database and a database of all encashed community prescriptions.

Results: One thousand eight hundred and forty seven subjects (26.3% of those with Type 2 diabetes) redeemed prescriptions for metformin. Of these, 3.5% were admitted with an acute myocardial infarction (71 episodes); 4.2% were admitted with cardiac failure (114 episodes); 21.0% received metformin and loop diuretics for cardiac failure concurrently; 4.8% developed renal impairment; and 2.8% developed chronic liver disease. The development of contraindications rarely resulted in discontinuation of metformin, for example only 17.5% and 25% stopped metformin after admission with acute myocardial infarction and development of renal impairment, respectively. In total, 24.5% of subjects receiving metformin, 6.4% of all people with Type 2 diabetes, had contraindications to its use. There was one episode of lactic acidosis in 4600 patient years.

Conclusions: This population-based study shows that 24.5% of patients prescribed metformin have contraindications to its use. Development of contraindications rarely results in discontinuation of metformin therapy. Despite this, lactic acidosis remains rare. Diabet. Med. 18, 483-488 (2001)

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • Contraindications
  • Databases as Topic
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diabetes Mellitus, Type 2 / physiopathology
  • Diabetic Nephropathies / epidemiology
  • Diuretics / therapeutic use
  • Family Practice / standards
  • Heart Failure / complications
  • Humans
  • Hypoglycemic Agents*
  • Liver Diseases / complications
  • Metformin*
  • Myocardial Infarction / complications
  • Practice Guidelines as Topic
  • Retrospective Studies
  • Scotland

Substances

  • Diuretics
  • Hypoglycemic Agents
  • Metformin