Physician adherence to hypertension treatment guidelines and drug acquisition costs of antihypertensive drugs at the cardiac clinic: a pilot study

Prescribing pattern surveys are one of the pharmacoepidemiological techniques that provide an unbiased picture of prescribing habits. Prescription surveys permit the identification of suboptimal prescribing patterns for further evaluation. The aims of this study were to determine the prescribing trend, adherence of the prescribers to the guideline, and the impact of drug expenditure on drug utilization at the cardiac clinic of Penang Hospital, Malaysia. This was a cross-sectional study. Demographic data of the patients, diagnoses and the drugs prescribed were recorded. The average drug acquisition costs (ADAC) were calculated for each antihypertensive drug class on a daily and annual basis. Adherence to the guideline was calculated as a percentage of the total number of patients. A total of 313 individuals fulfilled the inclusion criteria. The average age of the study population was 59.30 ± 10.35 years. The mean number of drugs per prescription in the study was 2.09 ± 0.78. There were no significant differences in the demographic data. Antihypertensive drugs were used in monotherapy and polytherapy in 20.8% and 79.2% of the patients, respectively. Adherence to the guideline regarding prescription occurred in 85.30% of the patients. The lowest priced drug class was diuretics and the highest was angiotensin-receptor blockers. In conclusion, the total adherence to the guideline was good; the adherence percentage only slightly decreased with a co-existing comorbidity (such as diabetes mellitus). The use of thiazide diuretics was encouraged because they are well tolerated and inexpensive, and perindopril was still prescribed for diabetic patients since it is relatively cheap (generic drug) and its daily dosage is beneficial.