Cost-Effectiveness of Antihypertensive Therapy in Patients Older Than 80 Years: Cohort Study and Markov Model

Abstract

BackgroundBlood pressure and antihypertensive treatment (AHT) generally increase with age, but there is uncertainty concerning the value of treatment at very advanced ages. ObjectivesTo estimate the cost-effectiveness of AHT in people aged 80 years and older. MethodsA Markov model compared AHT with no blood pressure treatment for prevention of cardiovascular disease. Outcomes were new stroke, coronary heart disease, and diabetes, with falls included as a potential complication of AHT. Costs were evaluated from a health system perspective. Incidence, mortality, and costs of healthcare utilization were estimated from linked primary and secondary care electronic health records for 98 220 individuals aged 80 years and older. Clinical effectiveness estimates were from the Hypertension in the Very Elderly Trial. Deterministic and probabilistic sensitivity analyses were conducted. ResultsIn the base case, AHT was associated with an additional 725 quality-adjusted life-years (QALYs) and £4.3 million per 1000, with an incremental cost-effectiveness ratio (ICER) of £5977 per QALY. The ICER was most sensitive to the cost of falls and relative risk reduction in stroke incidence. Probabilistic sensitivity analysis gave 95% uncertainty intervals: £5057 to £8398 per QALY in men and £4955 to £8218 per QALY in women. AHT for secondary prevention in participants with coronary heart disease gave an ICER of £9903 per QALY. ConclusionsAHT is estimated to be cost-effective in individuals aged 80 years and older, even if health benefits are smaller or side effects costlier than in the base case. Benefits and harms for vulnerable subgroups require further evaluation.