Introduction: In the next 30 years, the population of adults 75 years and older will more than double in the U.S., and high blood pressure is the most prevalent cardiovascular risk factor in this population. The impact of strategies for blood pressure control has not been evaluated in this population with special consideration of geriatric conditions that may alter the cost-effectiveness.
Methods: Based on the Cardiovascular Disease Policy Model, a Markov model of the U.S. population, we forecasted the population impact of blood pressure treatment over 10 years in adults aged 75-94 years, using the health care system perspective, and assuming an annual discount rate of 3%. Based on epidemiologic and trial data, we projected the impact of four potential negative events on cost-effectiveness in this geriatric population: 1) mild side effects, 2) polypharmacy (use of 5+ medications) associated cognitive impairment, 3) increased risk of falls/fracture, and 4) attenuated effectiveness of therapy in frail older adults
Results: We project that treatment to a systolic blood pressure target of 160 mmHg would result in the prevention of 65,000 cases of incident coronary artery disease, and 54,000 cases of incident ischemic stroke in adults 74-95 years. Based on a systolic blood pressure target of 140 mmHg, 191,000 cases of incident coronary artery disease, and 141,000 cases of incident ischemic stroke would be avoided. This would result in 729,000 additional years of life and 992,000 quality-adjusted life years (QALYs). The total health care costs of treating 75-94 year olds to a systolic blood pressure target of 140 mmHg would be $40.5 billion in the U.S., and the cost per QALY would be $40,800. The cost-effectiveness of treatment to a target of 140 mmHg would be worse in the presence of side effects ($ 51,000/QALY), polypharmacy ($ 58,400), fractures ($ 48,400), or frailty ($134,300).
Conclusions: Treatment of systolic blood pressure to a target of 140 mmHg would prevent the most cardiovascular events and result in the greatest QALYs gained. The presence of side effects, polypharmacy-related cognitive impairment, fractures, or frailty could substantially offset this benefit. Treatment strategies that are tailored to the health status of older adults are warranted.