Improvement in metformin and insulin utilisation in the Australian veteran population associated with quality use of medicines intervention programs

Pharmacoepidemiol Drug Saf. 2011 Apr;20(4):359-65. doi: 10.1002/pds.2094. Epub 2010 Dec 28.


Purpose: To examine the impact of 2001 and 2005 quality use of medicines (QUMs) diabetes programs implemented by National Prescribing Service (NPS) on the prevalence of utilisation of metformin and insulin among the Australian diabetes veteran population.

Methods: A retrospective observational study using Department of Veterans' Affairs pharmacy claims data. Diabetes population was defined as all veterans aged 55 and over who were dispensed medicines indicative of diabetes between 2000 and 2007. Prevalence of utilisation of metformin and insulin were assessed. Time series regression analysis was undertaken to study the effect on drug utilisation of NPS diabetes intervention programs.

Results: Of the diabetes population, over 55% has been dispensed metformin, and around 20% insulin. Across 2000-2007, metformin used as monotherapy has risen from 22.7 to 28.6% of the diabetes population and metformin concurrent with other diabetes medicines has increased from 32.3 to 36.5%. Insulin monotherapy has decreased from 13.9 to 11.5%, while insulin in combination with oral hypoglycaemics has increased from 6.1 to 11.1%. Twenty-four months post the onset of second NPS diabetes intervention, there was 4.2% relative increase in metformin use, and 13.5% relative increase in insulin used concurrently with oral hypoglycaemics, compared to the estimates without the interventions.

Conclusions: Changes in oral hypoglycaemics trends are towards metformin dispensing as part of ongoing diabetes management. Insulin trends have been away from monotherapy and towards concurrent dispensing with oral antidiabetic drugs. NPS QUMs programs for diabetes management were positively associated with these changes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Australia
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Drug Therapy, Combination
  • Female
  • Humans
  • Hypoglycemic Agents / administration & dosage
  • Hypoglycemic Agents / therapeutic use*
  • Insulin / administration & dosage
  • Insulin / therapeutic use*
  • Male
  • Metformin / administration & dosage
  • Metformin / therapeutic use*
  • Middle Aged
  • Practice Patterns, Physicians' / standards*
  • Quality Assurance, Health Care
  • Regression Analysis
  • Retrospective Studies
  • Time Factors
  • Veterans / statistics & numerical data


  • Hypoglycemic Agents
  • Insulin
  • Metformin