September 12th, 2012
Study Predicts Renal Denervation Will Be Cost-Effective in Resistant Hypertension
Larry Husten, PHD
Renal denervation (RDN) for resistant hypertension may be cost-effective and may provide long-term clinical benefits, according to a new analysis published in the Journal of the American College of Cardiology.
Benjamin Geisler and colleagues developed a model to predict the impact of the Medtronic Symplicity RDN system in patients with resistant hypertension. Over 10 years, according to the model, RDN treatment resulted in large differences in outcomes, though the benefits were less pronounced when projected over a lifetime.
Projected 10-Year Relative Risk:
- Stroke: 0.70 (reduced from 11.6% in the control group to 8.2% in the RDN group)
- MI: 0.68 (reduced from 9.6% to 6.5%)
- CHD: 0.78 (reduced from 24.8% to 19.4%)
- HF: 0.79 (reduced from 5.4% to 4.3%)
- ESRD: 0.72 (reduced from 2.9% to 2.1%)
- CV mortality: 0.70 (reduced from 12.5% to 8.7%)
- All-cause mortality: 0.85 (reduced from 23.0% to 19.5%)
Median survival was lengthened from 17.07 years to 18.37 years. The authors calculated an increase in quality-adjusted life-years (QALY) from 12.07 to 13.17 years, resulting in a discounted incremental cost-effectiveness ratio of $3071/QALY. Cost-effectiveness was “markedly below the commonly accepted threshold of $50,000 per QALY,” and might even be cost-saving, according to the authors.
The model assumes that RDN causes a long-term reduction in blood pressure, though current data from the Symplicity HTN-2 trial only extend to 36 months. However, the authors reported that RDN remained “cost-effective across a wide range of assumptions.”
Key word here is the last one – “assumptions”.
Prediction of reduction of CVD and ESRD on the basis of surrogate marker reduction (BP) failed measurably in the past. Significant reductions in BP failed to improve outcomes in a number of pharmaceutical trials:
Atenolol (Carlberg MA),HCTZ (multiple MAs, MRFIT, OSLO).Chlorthalidone (ALLHAT – 2 mm reduction over Lisinopril with identical CHD outcomes),Multiple ARBs (TRANSCEND, ROADMAP, iPRESERVE, etc.) And how many unpublished ones?
Bloodletting is certain to improve BP, and any barber can do it (or at least used to). So it can be very cost effective. And projected QALY cost will be acceptable, I am sure.
Yes, technology is exciting, and yes, interventionists are itching to start frying renal arteries and hospitals cannot wait to fill their new angio-suits.
However, is it prudent to jump on this technology before hard clinical outcome data are available?
Does anyone really thinks that we can eliminate excess CV risk in obesity-associated HTN (most of the resistant HTN I see in my practice now) by microwaving renal arteries? HTN is mostly an epiphenomenon in this situation .
Nevertheless, I think device will get a lot of support – from Medtronic, of course, interventionists and hospitals, and, of course, patients.
Instead of prudent/responsible lifestyle and weight loss they can have one time procedure done that “cures” HTN without drugs. What could possibly be better?
Sober look at facts and outcomes data, perhaps? I would not count on that. We are likely to see RDN Simplicity (what a name!) on the billboards by the highway in a year or two – along with Lasik, sleep labs, gastric banding drive-throug’s, etc.