الملخص الإنجليزي
Aim: To conduct a drug utilization review (DUR) to evaluate the appropriateness of use of losartan at Sultan Qaboos University Hospital (SQUH).
Objectives: To identify prescribing frequency of losartan at SQUH and compare the prescribing pattern of losartan to the standard treatment criteria.
Introduction: Hypertension remains a serious public health problem, as it is a major risk factor for coronary heart disease (CHD) and stroke. The prevalence rate of high systolic (2140 mmHg) or high diastolic (290 mmHg) blood pressure among the adult Omanis (>20 years) is 33%. DUR measures the pattern and quality of drug use by comparing practices with predetermined criteria and standards and by this way, an assessment of the quality of drug use can be made. Management of hypertension with angiotensin-II (AT-II) receptor antagonists e.g. losartan, is an effective treatment modality. Drugs acting on the renin- angiotensin system are contraindicated in pregnancy since they have been associated with fetal toxicity in humans. As losartan represent a significant percentage of the total antihypertensives cost, appropriate prescribing of losartan will rationalize its use and cost. Methods and Analysis: A three-month prospective observational study was conducted at SQUH. The study included all adult patients seen at SQUH outpatient clinics whose prescription contained losartan. Data were collected over a threemonth period from April to June 2003. All prescriptions containing losartan were collected and patients' files and medical records were reviewed. Data were recorded using data collection form and Statistical Package for Social Sciences (SPSS-9) was used for statistical analysis. Results: Two hundred and sixty seven patients (n=267) were eligible for this study. Losartan was indicated for hypertension in 71% of patients, for heart failure 12% and multiple-cardiovascular disorders (MCVD) 17%. Urea and electrolytes were monitored in 65% of patients and only 33% of patients had their liver functions tested. Hyperkalemia was found in 15% of patients on losartan. Forty seven percent of patients were obese and 34% had diabetes mellitus. Half of the study population (49%) was simultaneously using losartan and other antihypertensives. It was observed that 54% of patients were shifted from angiotensin converting enzyme (ACE) inhibitors to losartan and only five patients (2%) reported to have adverse drug reaction (ADR) with losartan. All these ADRs were documented in patients' files but none were reported to the pharmacy drug information service (DIS). Although 21% of the female patients included in the study were of childbearing age, pregnancy-related information was only offered to one patient (3%). The grand total cost of losartan, over the three-month study period was 5,930 Omani Rials (OR) $ 15,443 US. The grand total cost of losartan represented 12% of the total cost of antihypertensives (48,726 OR $ 126,892 US) used during the same study period. Conclusion: Losartan prescribing at SQUH was appropriate in terms of indications and dosage regimen. Monitoring of patient's electrolytes is essential before and after initiation of losartan therapy. Shared care approach between all healthcare providers should be encouraged to ensure an optimal health care for patients. Rational drug prescribing is needed to avoid unnecessary cost and maximize benefit from the available resources.
