ABC | Volume 111, Nº1, July 2018

Original Article Stevens et al The Economic Burden of Heart Conditions in Brazil Arq Bras Cardiol. 2018; 111(1):29-36 for this parameter, the study chosen was the most robust methodologically and provided a similar estimate to what could be derived from a study in Latin America. 17 For MI, based on a study of coronary heart disease patients, informal care hours were estimated to be 279 hours per year per patient. 18 Taxation revenue foregone was based on the average income tax rate for a single individual and the average indirect tax rate according to the OECD. 19,20 The estimated income tax liability was applied to the estimated total value of forgone earnings to determine the value of taxation lost. An adjustment was also applied for the number working in the ‘informal economy’ which is likely to reduce the taxation revenue collected. Exchange rates betweenUSD and the local currency were based on the average of the daily exchange rates from the International Monetary Fund from January 2015 to November 2015. Comorbidities As multiple conditions could affect one person simultaneously, the total cost of the four conditions was estimated by reviewing literature 21-23 that identified the number of individuals with two, three or four concomitant conditions as outlined in Figure 1. Where literature did not outline the concomitant rates between each of the four conditions, the sources were extrapolated until all combinations were derived. Cost-effectiveness analysis for HF To undertake the analysis, a targeted literature review was carried out to identify either published cost-effectiveness studies which could be adapted to the Brazilian context, or literature which could inform the design of, and inputs to, a cost-effectiveness model. The review identified a relatively recent network meta-analysis and cost-effectiveness analysis of TM and STS programs after discharge in patients with HF, conducted by the National Institute for Health Research in 2013. 24 This study was therefore used as the basis for a cost‑effectiveness analysis of STS and TM from the perspective of the Sistema Unico de Saude. Model structure A Markov model was constructed in TreeAge Pro©2015 to evaluate the cost-effectiveness of STS and TM compared with standard care (SC) for a hypothetical cohort of patients discharged in the last 28 days following HF-related hospitalizations. The model as shown in Figure 2 considered two different permanent health states, ‘alive at home’ and ‘dead’ as well as two temporary health states for ‘hospitalized due to HF’ and ‘hospitalized for all other causes’. The model is based on monthly cycles with half-cycle corrections. Time horizon, duration and discount rate As HF is a life-long condition after onset, the model captured a lifetime horizon of 30 years with patients progressing through the model until they either died or reached the end of the 30-year time horizon. It was assumed that the interventions of STS, TM and SC were provided for the full duration of the time horizon, outside of hospitalization. Both health system costs and quality-adjusted life-years (QALYs) were discounted at an annual rate of 5%. Data sources Efficacy estimates The monthly probability of death with SC following a non-fatal hospitalization was based on data from the CHARM study, 25 which followed 7,572 patients for a period of Table 2 – Financial cost of heart conditions in Brazil, 2015 (millions of reais) Category HF MI AF HTN Total (unadjusted) Total (adjusted for comorbidities) ^ Health system costs 14 469 16 119 3 697 1 098 35 382 35 382 65% 72% 94% 14% 63% 63% Productivity losses 7 663 6 257 225 6 927 21 071 20 858 35% 28% 6% 86% 37% 37% Income forgone by individuals* 3 528 4 540 156 2 063 10 287 10 196 16% 20% 4% 26% 18% 18% Income forgone by businesses* 333 403 31 4 378 5 145 5 050 2% 2% 1% 55% 9% 9% Opportunity cost of informal care by family/friends 2 404 196 2 600 2 596 11% 1% 5% 5% Tax revenue forgone by government** 1 399 1 117 37 486 3 039 3 016 6% 5% 1% 6% 5% 5% Total cost 22 132 22 375 3 921 8 025 56 454 56 241 Results in millions of reais. * : The result from absenteeism, reduced employment participation, and premature mortality. ** : Due to reduced income of individuals with heart conditions and their carers. ^ : Comorbidity totals do not sum to the total of the individual conditions as one person can have more than one condition and the interaction between conditions causes the total estimate of the four conditions together to vary. HF: heart failure; MI: myocardial infarction; AF: atrial fibrillation; HTN: hypertension. 31