A polypill designed to reduce the risk of cardiovascular disease would be cost-effective in Latin America, even in countries with low gross national incomes, according to an analysis published in the January issue of Health Affairs.
The polypill, a tablet that combines antihypertensive medicines to lower blood pressure and a statin to lower cholesterol, has been tested in both developed and developing nations. One study in the U.K., for instance, found that polypill usage reduced mean systolic blood pressure, diastolic blood pressure and low density lipoprotein cholesterol by 12 percent, 11 percent and 39 percent, respectively. That polypill consisted of half doses of amlodipine, losartan and hydrochlorothiazide with a standard dose of the statin simvastatin (Zocor, Merck). Results from the randomized Indian Polycap Study showed that daily polypill usage (12.5 mg thiazide, 50 mg atenolol, 5 mg ramipril, 20 mg simvastatin and 100 mg aspirin) reduced the risk of coronary heart disease and stroke by 62 percent and 48 percent, respectively.
To evaluate the cost-effectiveness of the polypill in Latin America, Leonelo E. Bautista, MD, MPH, DrPH, of the University of Wisconsin School of Medicine and Public Health in Madison, and colleagues combined results from the Indian Polycap Study with data from the Latin American Consortium Studies in Obesity. They designed a Markov model to measure the health benefits and costs of offering the same polypill used in the Indian trial to a hypothetical cohort of 30-year-old men and women. The model ran in one-year cycles for 70 years, with random changes each year according to predefined age- and sex-specific one-year risks of cardiovascular events and death.
Bautista and colleagues estimated the lifetime risk of cardiovascular disease, the cumulative number of quality-adjusted life-years (QALYs), accumulated costs and the cost-effectiveness ratio. They also evaluated the cost-effectiveness of the polypill in target groups based on age, obesity, metabolic syndrome and an expected 10-year cumulative risk of cardiovascular disease that was 15 percent or higher (high risk). They estimated the annual average cost of the polypill at $50 per person.
In a scenario of no intervention, they estimated the 10-year risk of coronary heart disease and stroke at 7.33 percent and 2.87 percent for women and 9.02 percent and 2 percent for men. Women’s lifetime risk of 29.1 percent would be reduced by 15 percent if a polypill was taken by women in the high-risk group. Men’s lifetime risk of 36.5 percent would be reduced by 21 percent if a polypill was taken by men in the high-risk group.
Among women, the polypill intervention in the high-risk group resulted in the lowest increase in cost per QALY gained, at an incremental cost-effectiveness ratio of $268 per QALY. A polypill intervention for men 55 years old and older provided the best approach, with an incremental cost-effectiveness ratio of $449 per QALY. Overall, the incremental cost-effectiveness ratio for women ranged from $158 (best case scenario) to $804 (worst case) per QALY and for men, from $365 to $933 per QALY.
“Health interventions have been considered very cost-effective if they gain one QALY at a cost lower than the per capita gross national income,” they wrote. Of the eight countries included in their analysis, Peru had the lowest per capital income, at $4,710. “The polypill would be very cost-effective even under the worst scenario and in the country with the lowest gross national income in our study (Peru), with a gross national income ($4,710) more than five times larger than the incremental cost-effectiveness ratio.”
They cautioned that policy makers should continue to focus on programs that emphasize healthy behavior and view the polypill as a complement to such efforts. They acknowledged that they did not examine the potential adverse effects of the polypill. Their model assumed the polypill provided a persistent change in blood pressure and blood cholesterol levels and the baseline risk of cardiovascular disease was taken from a single study.