ABC | Volume 112, Nº6, June 2019

Original Article Fernandes et al Lifestyle and costs of medicine use Arq Bras Cardiol. 2019; 112(6):749-755 been shown to play an important role in the development of many diseases, 11 but their direct relationship with the costs related to medicines use is unclear. For example, the occurrence of sleep disorders is highly prevalent in adults, 12 but its economic burden is unknown. 13 A longitudinal study carried out with 11,698 American employees identified that how worse were the sleep disorder reported the health care costs to increase in average US$ 725.15. 13 Similarly, in a 12-months study carried out in Taiwan, adults with positive diagnosis to obstructive sleep apnea were 66%more expensive (in terms of physician diagnoses, medications, treatments, surgeries, laboratory tests and diagnostic imaging) than those adults without the same diagnosis (US$ 1,734.10 versus US$ 1,041.30, respectively). 14 Conversely, improved levels of physical activity (PA) could reduce costs related to medicine use in adults, 15,16 but its role in the potential relationship between unhealthy lifestyle behaviors and costs of medicine use has not been studied to date. In this study, we examine the interrelationship between costs of medicine use and lifestyle behaviors (both healthy and unhealthy). Methods Sample The data comes from a cohort study carried out in the city of Presidente Prudente which presents human development index 0.806, 17 placed on western Sao Paulo State (which is the state of the most industrialized Brazilian federation) from February/June 2014 (baseline) to May/December 2015 (follow-up). Sample size estimation was based on an equation for the correlation coefficient. Due to the absence of specific data about the relationship between lifestyle behaviors and health care costs in Brazil, 16,18 we have adopted a correlation coefficient of 0.30 between PA and health care costs, 16,18 z = 1.96 and power of 80% (adopting the above- mentioned parameters, the minimum sample size required for this study was 86 participants). The inclusion criteria for participants were: 40-65 years old, no diagnosis of previous cardiovascular complications (e.g. stroke, heart attack), no diabetes complications (amputation or visual problems), no regular medication use, and no physical disability. Invitation to participate in the study was conducted using advertisements (ie posters) in the Sao Paulo State University in Presidente Prudente and gyms/fitness centers across the city. Interested participants contacted the research staff, who then checked the profile of the participants against the inclusion criteria (participants who met all the inclusion criteria signed a written consent form). One hundred ninety-eight adults contacted the research staff and were considered eligible and undertook baseline assessment. The analysis herein covered 118 subjects (44 men and 74 women) assessed at both baseline and follow-up (12 months later). The excluded people were due to (a) dropouts (n = 62) and (b) provision of less than seven days of pedometer use at baseline (n = 18). All procedures (questionnaires, pedometers and body composition assessment) were performed by trained staff of researchers (Professors, MSc and PhD students) following the protocols of the Laboratory of Investigation in Exercise (LIVE), Brazil. 19 The Ethics committee of the Sao Paulo State University (UNESP), campus of Presidente Prudente, approved the study. Costs of medicines use At baseline, the participants were given a questionnaire (in diary form) for medicine use and instructions (further clarification offered face to face by research staff) on how to fulfil the questionnaire. The participants reported the following data: (a) number and type of all medicines (prescribed and unprescribed); (b) how they obtained the medicines - through the Brazilian National Health System [BNHS] or out of pocket expenditure. The diary was filled for each of the 12months of the cohort study. At the end of the follow-up period, the research staff collected back the completed diaries (Table 1). To calculate the cost of medicines, we used national prices presented by BNHS (for medicines delivered by the BNHS) and market prices from drug stores in the study area (medicines obtained via personal expenses). Costs were computed in Brazilian currency (Real$) and converted to US dollar (US$) using the cambial information provided by the Central Bank of Brazil. Lifestyle behavioral variables PA was measured using both objective and subjective measures at baseline and follow-up. Objective measure of PA was collected using pedometers (Yamax digiwalker, SW200 model, Japan), and specified in terms of step count. At both assessments periods (baseline and follow-up), pedometers were worn by participants for seven consecutive days. The pedometers were fixed laterally at the hip and were taken off only during periods of sleep and water-based activities. Participants logged (at the end of each day) the total step count. In the present study, PA denoted the number of days (out of 14 days assessed) that ≥7,500 steps were achieved. In line with Tudor-Locke et al., 20 participants who reached ≥7,500 steps/day were classified as “sufficiently active”. The subjective measure of PA was collected using Baecke’s questionnaire. 21 The questionnaire is composed of 16 questions about three PA domains (occupational, sports participation and leisure-time PA). Data on SB at work (both baseline and follow up) were captured using the following question: “At work I sit”…; potential responses were: never [score attributed = 1], seldom [score attributed = 2], sometimes [score attributed = 3], often [score attributed = 4] and very often [score attributed = 5]). Quality of sleep was assessed at baseline and follow up using the Mini-Sleep Questionnaire, 22 which includes 10 questions, each one with seven possible answers (ranging from never to always). The sum of these 10 answers generates a numerical score ranging from 10 to 70 points (higher scores indicate worse sleep quality). Participants also self-reported at baseline and follow‑up smoking status (yes or no current smoker) and weekly alcohol consumption (number of days per week with alcohol consumption). 750