10th November 2017, Volume 130 Number 1465

Peter Murray, Hew Norris, Scott Metcalfe, Bryan Betty, Vanessa Young, Bronwyn Locke

Type 2 diabetes mellitus (T2DM) is a significant and costly public health issue in New Zealand.1–4 Māori and Pacific people bear a disproportionate burden of T2DM-related disease, contributing to ethnic…

Subscriber content

The full contents of this page is only available to subscribers.

To view this content please login or subscribe


Diabetes is a major health issue in New Zealand. In New Zealand, we have clear guidelines on how to treat diabetes. These guidelines state that if medication is to be started, metformin should be started first, followed by sulfonylureas. This research shows that these guidelines are being well followed in New Zealand, particularly when compared with other countries.



Type 2 diabetes mellitus (T2DM) is a significant public health issue in New Zealand. Effective management and glycaemic control is critical for reducing diabetes-related complications. Treatment guidelines are well established in New Zealand. Using dispensing data as a proxy for prescribing data, this paper aims to describe the pattern of first- and second-line antidiabetic agent (AA) dispensing for T2DM in New Zealand and assess adherence with treatment guidelines.


Analysis of national dispensing data for AA medications using the Pharmaceutical Collection database from 2007/08 to 2015/16.


Metformin monotherapy remains the most commonly prescribed first-line T2DM medication prescribed, accounting for 85% of initial agents prescribed. Sulfonylureas are the most common second-line agents used, accounting for 70% of all second-line agents.


There is a high degree of adherence with the T2DM treatment guidelines in New Zealand.

Author Information

Peter Murray, Medical Directorate, PHARMAC, Wellington; Hew Norris, Analysis, Corporate Directorate, PHARMAC, Wellington; Scott Metcalfe, Medical Directorate, PHARMAC, Wellington;
Bryan Betty, Medical Directorate, PHARMAC, Wellington; Vanessa Young, Operations Directorate, PHARMAC, Wellington; Bronwyn Locke, Engagement and Implementation Directorate, PHARMAC, Wellington.


Peter Murray, PHARMAC, 9/40 Mercer Street, Wellington 6011.

Correspondence Email


Competing Interests

The authors are (or were at the time of writing) employees of PHARMAC; the views expressed do not necessarily represent those of PHARMAC.


  1. Ministry of Health. Health Loss in New Zealand 1990–2013: A report from the New Zealand Burden of Diseases, Injuries and Risk Factors Study. Wellington: Ministry of Health.
  2. Coppell KJ, Mann JI, Williams SM, et al. Prevalence of diagnosed and undiagnosed diabetes and prediabetes in New Zealand: findings from the 2008/09 Adult Nutrition Survey. N Z Med J. 2013 Mar 1; 126(1370):23–42.
  3. Krebs J, Coppell KJ, Cresswell P, et al. Access to diabetes drugs in New Zealand is inadequate. N Z Med J. 2016 Jun 10; 129(1436):6–9.
  4. Ministry of Health. 2009. Report on New Zealand Cost-of-Illness Studies on Long-Term Conditions. Wellington: Ministry of Health.
  5. Nathan DM, Cleary PA, Backlund JY, et al; Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study Research Group. Intensive diabetes treatment and cardiovascular disease in patients with type 1 diabetes. N Engl J Med. 2005 Dec 22; 353(25):2643–53.
  6. New Zealand Guidelines Group. New Zealand Primary Care Handbook 2012. 3rd ed. Wellington: New Zealand Guidelines Group; 2012.
  7. BPAC. Managing patients with type 2 diabetes: from lifestyle to insulin. Best Practice Journal. 2015:72.
  8. PHARMAC. New Zealand Pharmaceutical Schedule August 2016. Wellington: PHARMAC.
  9. Inzucchi SE, Bergenstal RM, Buse JB, et al. Management of hyperglycemia in type 2 diabetes, 2015: a patient-centered approach: update to a position statement of the American Diabetes Association and the European Association for the Study of Diabetes. Diabetes Care. 2015 Jan; 38(1):140–9. doi: 10.2337/dc14-2441.
  10. Chang CH, Jiang YD, Chung CH, et al. National trends in anti-diabetic treatment in Taiwan, 2000–2009. J Formos Med Assoc. 2012 Nov; 111(11):617–24. doi: 10.1016/j.jfma.2012.09.009.
  11. Desai NR, Shrank WH, Fischer MA, et al. Patterns of medication initiation in newly diagnosed diabetes mellitus: quality and cost implications. Am J Med. 2012 Mar; 125(3):302.e1–7. doi: 10.1016/j.amjmed.2011.07.033.
  12. Raebel MA, Xu S, Goodrich GK, Schroeder EB, et al. Initial antihyperglycemic drug therapy among 241 327 adults with newly identified diabetes from 2005 through 2010: a surveillance, prevention, and management of diabetes mellitus (SUPREME-DM) study. Ann Pharmacother. 2013 Oct; 47(10):1280–91. doi: 10.1177/1060028013503624.
  13. Sargen MR, Hoffstad OJ, Wiebe DJ, Margolis DJ. Geographic variation in pharmacotherapy decisions for U.S. Medicare enrollees with diabetes. J Diabetes Complications. 2012 Jul–Aug; 26(4):301–7. doi:10.1016/j.jdiacomp.2012.04.001.
  14. Geier AS, Wellmann I, Wellmann J, et al. Patterns and determinants of new first-line antihyperglycaemic drug use in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract. 2014 Oct; 106(1):73–80. doi: 10.1016/j.diabres.2014.07.014. 
  15. Metcalfe S, Moodie P, Norris H, Rasiah D. Self-monitoring blood glucose test strip use with diabetes medicines in people with types 1 and 2 diabetes in New Zealand. N Z Med J. 2014; 127(1406):48–62. http://www.nzma.org.nz/journal/read-the-journal/all-issues/2010-2019/2014/vol-127-no-1406/6371 
  16. Khunti K, Millar-Jones D. Clinical inertia to insulin initiation and intensification in the UK: A focused literature review. Prim Care Diabetes. 2017 ; 11(1):3–12. doi: 10.1016/j.pcd.2016.09.003. URL: http://www.primary-care-diabetes.com/article/S1751-9918(16)30099-7/fulltext
  17. Strain WD, et al. Time to do more: addressing clinical inertia in the management of type 2 diabetes mellitus. Diabetes Res Clin Pract. 2014 Sep; 105(3):302–12. doi:10.1016/j.diabres.2014.05.005. URL: http://www.diabetesresearchclinicalpractice.com/article/S0168-8227(14)00219-8/abstract
  18. Tang T, Lord JM, Norman RJ, et al. Insulin-sensitising drugs (metformin, rosiglitazone, pioglitazone, D-chiro-inositol) for women with polycystic ovary syndrome, oligo amenorrhoea and subfertility. Cochrane Database Syst Rev. 2012; 5:CD003053. doi: 10.1002/14651858.CD003053.pub5
  19. Stephens JM, Gold KF, Botteman MF. Persistence patterns with oral hypoglycemic agents in type 2 diabetes. JCOM. 2002 Sep; 9(9):491–9.
  20. Guidoni CM, Borges AP, Freitas OD, Pereira LR. Prescription patterns for diabetes mellitus and therapeutic implications: a population-based analysis. Arq Bras Endocrinol Metabol. 2012 Mar; 56(2):120–7.
  21. Hassan YA, Mathialagan AM, Awaisu AH, et al. Trend in the use of oral hypoglycemic agents in an outpatient pharmacy department of a tertiary hospital in Malaysia (2003–2006). Asian J Pharm Clin Res. 2009; 2:40–6.
  22. Boccuzzi SJ, Wogen J, Fox J, et al. Utilization of oral hypoglycemic agents in a drug-insured US population. Diabetes Care. 2001; 24(8):1411–5.
  23. Clemens KK, Shariff S, Liu K, et al. Trends in Antihyperglycemic Medication Prescriptions and Hypoglycemia in Older Adults: 2002–2013. PloS one. 2015 Sep 3; 10(9):e0137596.
  24. Tanabe M, Motonaga R, Terawaki Y, et al. Prescription of oral hypoglycemic agents in patients with type-2 diabetes mellitus: a retrospective cohort study using a Japanese hospital database. J Diabetes Investig. 2016: Doi: 10.1111/jdi.12567.
  25. Karter AJ, Moffet HH, Liu J, et al. Achieving good glycemic control: initiation of new antihyperglycemic therapies in patients with type 2 diabetes from the Kaiser Permanente Northern California Diabetes Registry. Am J Manag Care. 2005; 11(4):262.
  26. Trinacty CM, Adams AS, Soumerai SB, et al. Racial differences in long-term adherence to oral antidiabetic drug therapy: a longitudinal cohort study. BMC Health Serv Res. 2009; 9(1):1.
  27. Abrahamson MJ. Should sulfonylureas remain an acceptable first-line add-on to metformin therapy in patients with type 2 diabetes? Yes, they continue to serve us well!. Diabetes care. 2015; 38(1):166–9.
  28. Genuth S. Should Sulfonylureas Remain an Acceptable First-Line Add-on to Metformin Therapy in Patients With Type 2 Diabetes? No, It’s Time to Move On!. Diabetes Care. 2015; 38(1):170–5.
  29. Chang YC, Chuang LM, Lin JW, et al. Cardiovascular risks associated with second-line oral antidiabetic agents added to metformin in patients with type 2 diabetes: a nationwide cohort study. Diabet Med. 2015; 32(11):1460–9.
  30. Morgan CL, Poole CD, Evans M, et al. What next after metformin? A retrospective evaluation of the outcome of second-line, glucose-lowering therapies in people with type 2 diabetes. J Clin Endocrinol Metab. 2012; 97(12):4605–12.
  31. Murray P, et al. Metformin and sulfonylurea prescribing in New Zealand – When are they being started? In preparation for the NZ Medical Journal.


The downloadable PDF version of this article is only available to subscribers.

To view this content please login or subscribe