Which is more important for the efficiency of hypertension treatment: hypertension stage, type of drug or therapeutic compliance?

OBJECTIVES: Hypertensive patients are a heterogeneous population that can be distributed in groups showing different cardiovascular risk and benefit from treatment. This study examines the cost-effectiveness of arterial hypertension treatment by age, sex, arterial hypertension stage, type of drug used and level of treatment compliance.
DESIGN: Markov models combining absolute risks for stroke, coronary heart disease and all causes of death with relative risks from clinical trials and observational studies. Data on health costs were collected from hospitals and primary care settings in the Basque Country (Spain).
RESULTS: Cost-effectiveness ratios vary from 34,516 euros/quality adjusted life year (QALY) gained in 30-year-old women to 3,307 euros/QALY in 80-year-old men. A treatment compliance of 50% increases these values to 45,270 and 4,905 euros/QALY, respectively. Treatment of arterial hypertension stage II shows lower ratios (19,798 euros/QALY in 30-year-old women and 1,918 euros/QALY in 80-year-old persons). Cost-effectiveness ratios for arterial hypertension stage I vary from 645 euros/QALY in 80-year-old men for diuretics to 47,325 euros/QALY in 30-year-old women for inhibitors of the angiotensin converting enzyme.
CONCLUSIONS: There are large variations in the cost-effectiveness of arterial hypertension treatment depending on age, sex, arterial hypertension stage, drug used and compliance. Improvement of treatment compliance yields the greatest gain both in effectiveness and efficiency.