Pattern analysis and variations in the utilization of antihypertensive drugs in Taiwan: a six-year study.

BACKGROUND In the last few years there have been changed in the pattern of consumption of antihypertensive drugs in other countries. Factors causing this variability include differences in the effectiveness of detection, guidelines for the management of hypertension, and differences in national health insurance systems among countries. AIM The aim of this study was to reveal patterns in the use of antihypertensive drugs in Taiwan over a six year period (2001 to 2006) and compare these results with data from other countries. MATERIALS AND METHODS This study performed descriptive analysis of data from the National Health Insurance Research Database (NHIRD) of Taiwan, and compared these findings with similar findings from around the world. Quantities were standardized using the defined daily dose (DDD) per 1000 inhabitants per day (DID) in accordance with WHO anatomical therapeutic classification and DDD measurement methodology. RESULTS The total number of DDDs prescribed in Taiwan increased from 0.66 billion in 2001 to 1.08 billion in 2006, representing 80.6 and 129.2 DID in 2001 and 2006, respectively. This indicates a significant increase in the prescription of antihypertensive drugs in Taiwan over this period. The average annual increase ranged from 10.7% for calcium channel blockers (CCBs) to 22.1% for angiotensin II receptor blockers (ARBs). All of these patterns were statistically significant (p < 0.05). The rapid increase in the use of ARBs resulted in its surpassing ACEIs with the second highest DID (21.9) in 2006. Though the proportional use of CCBs and ARBs has increased significantly, the use of thiazide diuretics remains low. CONCLUSIONS The consumption of antihypertension drugs in Taiwan increased during the period studied and the highest average annual increases were for ARBs and CCBs. Overall consumption of antihypertension drugs also increased in other countries, but differences in the relative increase for each class of drug suggest that further study may be required to clarify the origins and causes.