Tailoring antihypertensive treatment to cardiovascular benefits may improve outcomes

Tailoring antihypertensive treatment to cardiovascular benefits rather than specific blood pressure targets may improve outcomes and result in less medication use, according to a new study using simulation models.

Researchers used data from the National Health and Nutrition Examination Survey III to develop a nationally representative sample of U.S. adults who were 30 to 85 years of age and had no history of myocardial infarction, stroke or severe congestive heart failure. They created a simulation model that would estimate the effect of 5 years of antihypertensive treatment based on specific blood pressure goals and 5 years of treatment based on estimated reduction in cardiovascular disease (CVD) events. Meta-analyses of randomized trials were used to derive estimates of effect size, and the researchers determined how many quality-adjusted life-years (QALYs) would be saved by using each treatment strategy.

In the base-case treat-to-target strategy, patients received new blood pressure medication if the observed blood pressure was 140/90 mm Hg or higher (130/85 or higher for diabetic patients). Medications were then added on a sequential basis until patients were taking 4 medications or until the target blood pressure was reached. In the benefit-based strategy, patients moved to the next stage of therapy if they had an observed systolic blood pressure above 150 mm Hg or if it was predicted that their rate of CVD events would decrease by more than a 1.7% chance of an event averted over 5 years of therapy (that is, patients got a new medication if it was deemed highly likely to prevent a CVD event). Patients were then assessed in a Markov model, and QALYs lost per event were estimated. In the primary analysis, patients treated with the treat-to-target strategy were compared with those treated using the benefit-based strategy. The study was published early online Nov. 4 by Circulation.

Overall, the model estimated that 55% of 176 million Americans would receive the same treatment regardless of which approach was used and that 45% would receive different treatments. A total of 26.5% of the total population would receive more intensive treatment with the treat-to-target strategy, resulting in an additional 1.9 medications per person and 204 QALYs saved per 1,000 people treated for 5 years. A total of 18.7% of the total population would receive more intensive treatment with the benefit-based strategy, resulting in 2.5 medications per person and 487 QALYs saved per 1,000 people treated for 5 years. In the 55% of patients who received the same treatment regardless of approach, benefit-based treatment was estimated to prevent approximately 900,000 CVD events, save 2.8 million additional QALYs and use 6% fewer medications over 5 years. In the 45% of patients who received different treatments based on the approach used, benefit-based treatment was estimated to save 159 QALYs per 1,000 treated patients versus 74 QALY per 1,000 patients treated to target.

The authors acknowledged that their study was limited by the available evidence, that simulation models should always be interpreted with caution, and that they were not making global recommendations about treatment intensity. They also noted that determining potential net benefit using untreated cardiovascular risk, blood pressure and current treatment regimen would be difficult for physicians to do on their own and that their model would need to be incorporated into electronic medical records or made available online for ease of calculation. However, they concluded that their results suggest more effective prevention of CVD events when antihypertensive treatment is based on potential benefit.

The authors of an accompanying editorial called the study timely and noted that it, together with previous research, supports the idea of treating hypertension based on cardiovascular risk. However, they called for further research to evaluate the potential effects of such changes in strategy. “The case to move on from blood pressure targets to risk-based targets is (and has always been) compelling,” they wrote. “But bringing about actual change in the clinic requires much more work. An important part of this involves the development of innovative strategies by which to more effectively incorporate risk-based management approaches into usual clinical practice.”