Trends in Antihypertensive Drug Use in the United States

Abstract

Context. —The choice of pharmacological treatment for the approximately 50 million people in the United States with hypertension has important therapeutic and financial implications. Objectives. —To describe national antihypertensive medication prescribing patterns for 1992 and 1995; to explore the influence of the Fifth Joint National Committee on the Detection, Evaluation, and Treatment of High Blood Pressure (JNC V), published in 1993, which recommended diuretics and β-blockers as firstline antihypertensive therapy unless contraindicated; and to estimate the impact of these prescribing patterns on the cost of antihypertensive treatment. Design. —All prescriptions for drugs approved for the treatment of hypertension dispensed by 35000 retail pharmacies were tabulated for 1992 and 1995 (62% of all US retail pharmacies were surveyed). Main Outcome Measures. —Number of prescriptions for each dosage form of medication and national cost estimates based on wholesale costs of medications dispensed. Results. —In 1992, of the 10 most frequently prescribed antihypertensive drugs, 3 were calcium antagonists, 3 were angiotensin-converting enzyme (ACE) inhibitors, 3 were β-blockers, and 1 was the combination of triamterene and hydrochlorothiazide. In 1995,4 were calcium antagonists, 3 were ACE inhibitors, 1 was a β-blocker, 1 was the combination of triamterene and hydrochlorothiazide, and 1 an a-blocker. In 1992, calcium antagonists accounted for 33% of antihypertensive prescriptions compared with 38% in 1995, ACE inhibitor use went from 25% to 33%, β-blocker use from 18% to 11% and diuretic use from 16% to 8%. The estimated wholesale costs for calcium antagonists in 1995 dollars increased from $2.67 billion in 1992 to $2.86 billion in 1995; ACE inhibitor costs increased from $1.37 billion to $1.67 billion; costs for diuretics declined from $353 million to $168 million; and costs for β-blockers declined from $763 million to $433 million. Conclusions. —From 1992 to 1995 use of calcium antagonists and ACE inhibitors for treatment of hypertension increased and diuretics and β-blockers declined, suggesting that the recommendations from JNC V had little effect on prescribing patterns. The cost implications of these practice patterns are enormous.