December 5, 2005Circulation146 citationsOpen Access
View Full PaperCost-Effectiveness Analysis of Hypertension Guidelines in South Africa
Key Result
Initiating hypertension treatment based on absolute cardiovascular risk is more effective and less expensive than using blood pressure level targets, with ICERs ranging from $700 to $11,000 per QALY.
Structured PICO
Does initiating hypertension treatment based on absolute CVD risk improve cost-effectiveness compared to blood pressure level thresholds in adults without CVD?
P
Population
Hypothetical cohort of all adults without CVD in South Africa
I
Intervention
Initiation of hypertension drug treatment based on absolute 10-year CVD risk thresholds (40%, 30%, 20%, and 15%)
C
Comparator
Initiation of treatment based on blood pressure levels (160/95 and 140/90 mm Hg) or no treatment
O
Outcome
Incremental cost-effectiveness ratio (dollars per quality-adjusted life-year gained)
Initiating hypertension treatment based on absolute cardiovascular risk rather than blood pressure thresholds is more cost-effective in South Africa.
Abstract
BACKGROUND: Hypertension is responsible for more deaths worldwide than any other cardiovascular risk factor. Guidelines based on blood pressure level for initiation of treatment of hypertension may be too costly compared with an approach based on absolute cardiovascular disease (CVD) risk, especially in developing countries. METHODS AND RESULTS: Using a Markov CVD model, we compared 6 strategies for initiation of drug treatment--2 different blood pressure levels (160/95 and 140/90 mm Hg) and 4 different levels of absolute CVD risk over 10 years (40%, 30%, 20%, and 15%)--with one of no treatment. We modeled a hypothetical cohort of all adults without CVD in South Africa, a multiethnic developing country, over 10 years. The incremental cost-effectiveness ratios for treating those with 10-year absolute risk for CVD >40%, 30%, 20%, and 15% were 700 dollars, 1600 dollars, 4900 dollars, and 11,000 dollars per quality-adjusted life-year gained, respectively. Strategies based on a target blood pressure level were both more expensive and less effective than treatment decisions based on the strategy that used absolute CVD risk of >15%. Sensitivity analysis of cost of treatments, prevalence estimates of risk factors, and benefits expected from treatment did not change the ranking of the strategies. CONCLUSIONS: In South Africa, current guidelines based on blood pressure levels are both more expensive and less effective than guidelines based on absolute risk of cardiovascular disease. The use of quantitative risk-based guidelines for treatment of hypertension could free up major resources for other pressing needs, especially in developing countries.