Psy106 - Cost-Effectiveness of Rare Diseases in Spain

Abstract

OBJECTIVES: Obesity is associated with elevated risks of developing major costly medical complications and impaired quality of life. The objective of this study was to create a core obesity model to compare weight management interventions, by assessing impacts on BMI and patho-physiological parameters to estimate longterm complications. METHODS: We developed a life-time Markov model with health states reflective of complications which: 1) are highly related to obesity according to the World Health Organization; 2) respond to weight loss, 3) have substantial consequences on costs, quality of life and/or life expectancy. Selected complications were: type 2 diabetes (T2D), obstructive sleep apnoea, cardiovascular disease (acute coronary syndrome [ACS], stroke), cancers (colorectal, endometrial and breast) and osteoarthritis resulting in knee replacement. Actual shortterm effects of specific interventions on BMI, blood pressure, lipids and HbA1c observed in clinical trials were translated into long-term risks of obesity complications, using published or newly developed risk-prediction equations. RESULTS: As an example, in a European cohort, mean age 45 years and BMI 37 kg/ m2, over a 10-year horizon the model predicted 5.0% mortality, 5.8% ACS and 2.1% stroke. Knee replacement occurred in 6.3% of the cohort and the proportion alive with T2D was 5.0%. Following a reduction of 3 BMI units, all other factors remaining unchanged, mortality dropped to 4.8%, with ACS and stroke incidences decreasing to 5.5% and 2.0%. The incidence of knee replacement was reduced to 4.4% and the proportion alive with T2D was 3.8%. CONCLUSIONS: The presented Core Obesity Model is novel in assessing the long-term effects of weight management interventions on such a comprehensive set of obesity medical complications. This model can therefore be used to inform cost-effectiveness analyses on the treatment of adult patients with obesity, with the usual limitations as no prospective long-term data exist on hard outcomes after intentional weight changes.