Estimativa do custo da asma em tratamento ambulatorial especializado em unidade universitária no Sistema Único de Saúde

Abstract

Asthma is considered a health problem worldwide. It is necessary to expand our knowledge in different regions of the world, including its associated costs. The major aim was to estimate economic costs of asthma treatment in a cohort of persistent asthmatics with different severity levels under specialized ambulatory care. Secondary aims were to analyze the clinical and socioeconomic characteristics of this population and to estimate the incremental cost associated to rhinitis and respiratory infections. Patients &#8805; 6 years old with persistent asthma were consecutively included from March 2011 to September 2012. They made routine clinical visits with 3 to 4-month intervals and 2 interviews with 6-month intervals. Clinical variables and asthma, rhinitis and respiratory infections (RI) primary data on costs were collected directly from patients or their parents (patients under 18 years old), regarding the two 6-month prior periods in a societal perspective. Brazilian costs were converted into USD using the purchasing power parity in 2012 (US$ 1.00=R$ 1.71). One hundred and eight out of 117 subjects completed the study. 73.8% were women, 60.1% lived far from the health care unit. Chronic rhinitis was present in 83.3% and more than 50.0% were overweight or obese, in whom the prevalence of severe asthma was greater (p=0.001). 75% of the students and half of the workers had missed activity days because asthma. Mean monthly family income (MFI) was US$ 915.90 (SD=879.12). The estimated mean total cost of asthma, rhinitis and RI was US$ 1,276.72 per patient-year (SD=764.14) and the mean specific annual asthma cost was US$ 1,140.94 (SD=760.87) per patient. Obese, severe or uncontrolled asthmatics had greater costs compared to non-obese, mild/moderate and controlled ones, respectively (p<0.05 in all comparisons). The population had medium to low socio-economic status, a high prevalence of associated chronic rhinitis and overweight or obesity. High body weight and lower MFI were more frequent among patients with greater severity and worse control, respectively. Obese, severe or uncontrolled asthmatics had greater costs. Asthma had a great impact on absenteeism. The mean cost of asthma was equivalent to the half of that in European Union and United States of America and was greater than the mean of Asia-Pacific region. In an ideal scenario, where all asthmatics would be receiving GINA guided treatment in the Unified Health System (UHF), like ours, the total cost of asthma would be equivalent to 3.4 to 4.5% and 0.4 to 0.6% of Brazilian health gross domestic product (HGDP) and Brazilian GDP, respectively. Public health strategies with programs aiming get better control and stimulating weight reduction could contribute to lower cost of asthma, possibly making the offer of free asthma medication to all persistent asthmatics in UHF a more achievable task. We recommend to expand this study to other different regions.