The questionable use of antihypertensive drugs in the Italian Liguria Region in the year 2003

Abstract

In the last 30 years, countless studies have shown that antihypertensive drug therapy substantially reduces the risk of hypertension-related morbidity and mortality. However, the optimal choice for initial pharmacotherapy of hypertension is still controversial. The guidelines for hypertension management agree on many items but differ on a very important point: the drug of first choice. The Seventh Report of the US Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure [1] and the World Health Organization/International Society of Hypertension Statement on Management of Hypertension [2] recommend, for uncomplicated hypertension, a thiazide diuretic, either alone or combined with drugs from other classes, and delineate specific conditions that are compelling indications for the use of other antihypertensive drug classes. The European guidelines [3] state that all available drug classes are suitable for the initiation and maintenance of treatment and underline that the benefits of the antihypertensive therapy are, for the most part, due to lowering of blood pressure per se and depend scarcely on the type of drug used. We deemed that it was of interest to examine the pattern of prescribing for hypertension in our country, the Italian Liguria Region, in the course of the year 2003. In this year, the inhabitants of the region were 1,572,197 (25.4% ‡65 years old), and the incidence of hypertensive patients was 13.9% [4]. The consumption of antihypertensives in the year 2003 was determined in terms of defined daily doses (DDDs) of each drug that was calculated from the number of the pharmaceutical preparations of each drug consumed during this year as obtained from the data base of the pharmaceutical department of the region. In the year 2003, the DDDs of all antihypertensive drugs were 167,090,040, and the corresponding expenditure amounted to Euro 94,916,866. The subdivision of DDDs in the six classes of antihypertensives of the anatomic–therapeutic– chemical classification of the European Pharmaceutical Market Association provides for each class the DDDs consumed in this year and the corresponding expenditure (Table 1). Angiotensin-converting enzyme (ACE) inhibitors were the most consumed; ACE inhibitors alone accounted for 27.63% of total DDDs, and ACE inhibitors in combination with a thiazide-type diuretic accounted for 10.32%. The DDDs of calcium antagonists were 22.78% of all DDDs. Angiotensin II antagonists alone accounted for 11.44% of total DDDs, and angiotensin II antagonists in combination with hydrochorothiazide accounted for 6.26%. The DDDs of betablockers alone were 10.47% of all DDDs, and the DDDs of the beta-blockers in combination with a thiazide-type diuretic were only 1.93%. The DDDs of diuretics accounted for 5.33% of total DDDs, but the DDDs of thiazide and thiazide-like diuretics were only 41.3% of the DDDs of all diuretics and 2.63% of total DDDs. The remaining antihypertensives (methyldopa, clonidine, doxazosin, terazosin, urapidil, and minoxidil) were the less used drugs, their DDDs accounting for 3.84% of the DDDs of all antihypertensives. Antihypertensive drugs are also prescribed for cardiovascular diseases other than hypertension, e.g., as antianginal or in the case of congestive heart failure. Therefore, even if this alternative use is generally estimated to be in the aggregate around 15% [5], no definitive conclusions can be drawn from data listed in Table 1. It is, however, possible to formulate the folL. Robbiano AE A. Martelli AE Giovanni Brambilla Department of Internal Medicine, Pharmacology and Toxicology Unit, University of Genoa, Viale Benedetto XV 2, I-16132 Genoa, Italy