Prescribing of antihypertensive agents in public primary care clinics – Is it in accordance with current evidence?

  • AS Ramli
  • M Miskan
  • KK Ng
  • Ambigga D
  • Nafiza MN
  • Mazapuspavina MY
  • J Sajari
  • R Ishak
Keywords: Evidence-based, guideline, hypertension, prescribing, primary care

Abstract

Background: Large population surveys in Malaysia have consistently shown minimal improvement of blood pressure controlrates over the last 10 years. Poor adherence to antihypertensivemedication has been recognized as a major reason for poorcontrol of hypertension. This study aimed to describe the prescribing pattern of antihypertensive agents in 2 public primarycare clinics and assess its appropriateness in relation to current evidence and guidelines.

Methods: A cross-sectional survey to describe the prescribing pattern of antihypertensive agents was carried out in 2 publicprimary care clinics in Selangor from May to June 2009. Hypertensive patients on pharmacological treatment for ≥1 year whoattended the clinics within the study period of 7 weeks were selected. Appropriate use of antihypertensive agents wasdefined based on current evidence and the recommendations by the Malaysian Clinical Practice Guidelines (CPG) on theManagement of Hypertension, 2008. Data were obtained from patients’ medical records and were analysed using the SPSSsoftware version 16.0.

Results: A total of 400 hypertensive patients on treatment were included. Mean age was 59.5 years (SD ±10.9, range 28 to91 years), of which 52.8% were females and 47.2% were males. With regards to pharmacotherapy, 45.7% were on monotherapy,43.3% were on 2 agents and 11.0% were on ≥3 agents. Target blood pressure of <140/90mmHg was achieved in 51.4% ofpatients on monotherapy, and 33.2% of patients on combination of ≥2 agents. The commonest monotherapy agents beingprescribed were β-blockers (atenolol or propranolol), followed by the short-acting calcium channel blocker (nifedipine). Thecommonest combination of 2-drug therapy prescribed was β-blockers and short-acting calcium channel blocker.

Conclusion: This study shows that the prescribing pattern of antihypertensive agents in the 2 primary care clinics was notin accordance with current evidence and guidelines. β-blockers and short-acting preparations were commonly used both asmonotherapy and combination treatment. Thiazide diuretics, ACE inhibitors and long acting calcium channel blockers wereunderutilised in this study, despite robust evidence to support their use. Evidence have also shown that simplifying thenumber of daily doses is effective in improving adherence, therefore a wider use of generic once daily preparation should bestrongly advocated in public primary care clinics.

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Published
2012-03-31
How to Cite
RamliA., MiskanM., NgK., DA., MNN., MYM., SajariJ., & IshakR. (2012). Prescribing of antihypertensive agents in public primary care clinics – Is it in accordance with current evidence?. Malaysian Family Physician, 5(1), 5. Retrieved from https://www.e-mfp.org/ojs3/index.php/MFP/article/view/96
Section
Original Articles