Cost effectiveness of rimonabant use in patients at increased cardiometabolic risk: estimates from a Markov model

Summary

Rimonabant, the first selective CB-1 receptor blocker, is expected to reduce cardiometabolic risk substantially. This study assesses the economics of such treatment in patients at elevated cardiometabolic risk.

A Markov model was developed using data from the Rimonabant in Obesity (RIO) trial, published risk equations, and UK cost and utility data. Patients begin either in a diabetic or a non-diabetic state and can transition to cardiovascular disease or to death (based on UK life tables). Transitions to diabetes and subsequent cardiovascular events are also counted. Resource use due to events and long-term management were translated to UK costs (2005 GBP). Tariffs for events and states were applied to age-dependent utilities. Extensive univariate and multivariate probabilistic sensitivity analyses were carried out.

Over 10 years, 8% will suffer a cardiovascular event with a loss of more than 1,000 quality-adjusted life years (QALYs) and a cost of more than £500,000 per 1,000 patients. Projecting risk for a lifetime, 1 year of rimonabant use is estimated to gain >65 QALYs at £8,574/QALY. In probabilistic sensitivity analysis, incremental cost-effectiveness ratios varied from £2,657 to £22,141/QALY.

Based on the metabolic effects seen in clinical trials, rimonabant should reduce cardiovascular risk in obese or overweight people at reasonable cost.     

Evaluating the effects of area closure for recreational fishing in a coral reef ecosystem: The benefits of an integrated economic and biophysical modeling

This paper presents an integrated agent-based model of recreational fishing behavior within a reef ecosystem as a platform for the evaluation of recreational fishing management strategies. Angler behavior is described using econometrically estimated site choice models, with site choice among anglers driven by site attributes and angler characteristics. The biophysical model represents the marine reef environment as a system with different trophic levels identifying algal and coral growth as well as two types of fish (piscivores and herbivores). Ecosystem dynamics are driven by interactions within the trophic levels and interaction between fish populations and fishing activities.The model is used to simulate recreational fishing activities and their interactions with the environment. Recreational fishing sites from the Ningaloo Marine Park, an iconic coral reef system in Western Australia, are used as a case study. A set of management strategies, including “business-as-usual” and different site closure durations, are assessed for two different levels of fishing pressures. The results show that not only the effectiveness but also the distribution of management impacts across space and over time can be very different from what one would expect without the benefit of integrated modeling.