Intensive blood pressure management may be cost-effective

An analysis found that intensive blood pressure management for patients with hypertension and an increased risk for cardiovascular events costs $23,777 per quality-adjusted life-year (QALY) gained.

That cost-effectiveness ratio provided good value, according to the researchers, who added that an intensive approach would be cost-effective even if there were significantly more adverse events than they assumed. They noted that the willingness to pay threshold was $50,000 per QALY gained.

Lead researcher Ilana B. Richman, MD, of the Palo Alto VA Health Care System in Palo Alto, California, and colleagues published their results online in JAMA Cardiology on Sept. 14.

The researchers noted that the SPRINT (Systolic Blood Pressure Intervention Trial) reported that a target systolic blood pressure of 120 mm Hg reduced the rate of cardiovascular morbidity and mortality by 25 percent compared with a normal target of 140 mm Hg. The trial included adults with hypertension who were at an elevated risk for cardiovascular disease but did not have diabetes.

They also mentioned that participants in the intensive management group required additional medications and physician visits and had higher rates of some serious adverse events. The number needed to treat was approximately 198 patients to avert one cardiovascular event or death per year, while the number needed to harm was approximately 56 patients per year.

For this analysis, the researchers developed a decision analytic Markov model that tracked a simulated cohort of 68-year-old adults for the rest of their lives. The participants were at risk for cardiovascular events, including MI, stroke and congestive heart failure.

The researchers assumed that participants who underwent intensive blood pressure management received three blood pressure medications and saw their physicians three times per year. Meanwhile, participants in the standard treatment group took two medications and saw their physicians two times per year. When participants had an MI, stroke or heart failure, the researchers assumed they returned to standard management.

The model had similar rates of event-free survival than those found in the SPRINT study, according to the researchers.

After five years, the rates of nonfatal MI were 3.8 percent in the standard group and 3.2 percent in the intensive group, while the rates of nonfatal stroke were 2.3 percent and 2.1 percent, respectively. The rates for heart failure were 3.2 percent and 2.0 percent, respectively, while the rates for death were 7.8 percent and 5.7 percent, respectively.

The estimated quality-adjusted life expectancy was 9.6 years in the standard management group and 10.5 years in the intensive management group, while the lifetime healthcare costs were $155,261 and $176,584, respectively.

Based on those estimates, the researchers calculated intensive blood pressure management cost $23,777 per QALY gained. They also mentioned that a probabilistic sensitivity analysis found that intensive blood pressure management was preferred in 84 percent of simulations at a willingness to pay threshold of $50,000 per QALY gained.

The researchers cited a few limitations of their model, including that it drew largely from the SPRINT study findings. They also did not include every possible consequence of hypertension in the model, including long-term renal complications of hypertension or hypertension treatment. In addition, the model did not account for repeated cardiovascular events.

“Concerns about costs of treatment and adverse events might temper enthusiasm for intensive blood pressure management, especially given the number needed to treat described in SPRINT,” the researchers wrote. “Our analysis indicates that unless adverse events are markedly higher or benefits are substantially lower than observed in SPRINT, intensive blood pressure management is both effective and cost-effective in patients at high cardiovascular risk. These analyses can inform clinicians, provider organizations, and guideline developers as they translate the results of SPRINT into practice.”