Analytical approach:
The analysis was based on a state-transition Markov model with two time horizons: 10 years and lifetime. The authors stated that a societal perspective was adopted.
Effectiveness data:
Clinical inputs were based on evidence taken from systematic searches of literature catalogued in PubMed. Treatment effect and patients characteristics were obtained from the randomised Simplicity HTN-2 trial which compared renal denervation plus standard of care with standard of care in patients resistant to hypertensive drugs. Transition probabilities were calculated on the basis of published large-scale cohort studies such as the Framingham Heart Study. Mortality was based on USA estimates. Reductions in systolic blood pressure were key inputs of the model.
Monetary benefit and utility valuations:
Utility valuations were taken from published studies but details were not provided.
Measure of benefit:
Quality-adjusted life-years (QALYs) and life-years were used as summary benefit measures and were discounted at an annual rate of 3%.
Cost data:
The economic analysis included costs of stroke, myocardial infarction, heart failure, angina pectoris, end-stage renal disease, hypertension and renal denervation. Costs were presented as macro-categories (no breakdown of items provided). All economic data (including cost and cost-effectiveness analyses) were taken from published sources obtained from a review of the literature (no details on these studies were reported). Costs were in US dollars ($) and were discounted at a yearly rate of 3%. The price year was 2010.
Analysis of uncertainty:
Various approaches were used to deal with the issue of uncertainty. One-way sensitivity analyses varied all parameters. Ranges were based on the authors’ opinions or published sources. Alternative assumptions about baseline systolic blood pressure and other model pathways were considered. Threshold analyses were performed to identify how large changes to individual inputs needed to be to exceed the conventional threshold of $50,000 per QALY. A comprehensive probabilistic sensitivity analysis was conducted using distributions based on published sources or expert opinions.