Efeitos da temperatura ambiente na mortalidade por infarto agudo do miocárdio

Abstract

Acute myocardial infarction (AMI) is the leading cause of death in Brazil. Studies of the effects of temperature on AMI mortality have been developed in several countries, but in Brazil there are few investigations. This paper aims to analyze the influence of air temperature on AMI mortality and the modifying effect of family health strategy (FHS) coverage on this association in Brazil. Data on mortality from AMI, FHS coverage and population data provided by DATASUS were used. Daily temperature data were ob-tained by reanalysis (ERA-Interim). To study the time series of mortality due to AMI, corrections were made to mortality rates due to ill-defined causes, garbage codes and underreporting. Time series were analyzed using the Joint Point-segmented linear re-gression technique. To investigate the effect of ambient temperature on AMI mortality, daily records of AMI deaths and ambient temperature were considered using the non-linear distributed delay model (DLNM). To analyze the modifying effect of ESF Cover-age on the association between room temperature and AMI mortality, a two-step anal-ysis was performed with estimation of relative risk in each microregion and then meta-analysis and meta-regression by region with ESF Coverage data. The results showed that mortality decreased more in females (-2.2%; 95%CI:- 2.5;-1.9) than in males (-1.7%; 95%CI:-1.9;-1.4) and more in capitals (-3.8%; 95%CI:- 4.3;-3.3) than in interior (-1.5%; 95%CI -1.8;-1,3). There was an increase for men living in the interior of the North (3.3; 95%CI:1.3;5.4) and Northeast (1.3%; 95%CI:1.0;1.6). The regions North and Northeast showed no association between temperature and AMI mortality. The lowest risk ranged from 22 ° C to 28 ° C, respectively in the South and Brasilia. The low temperatures associated with the highest risk of mortality were observed in the same areas, ranging from 5 ° C to 15 ° C. Regarding the high temperatures the maxi-mum risk was observed in the average daily temperature 31.3 ° C in Rio de Janeiro. The number of deaths attributable to cold was 597 / year, and those attributable to heat averaged 117 / year. The Southeast region had an association between temperature and deaths from acute cold AMI (RR:1.28; 95%CI: 1.23-1.32); moderate cold (RR:1.12; 95%CI:1.08 -1.15); moderate heat (RR:1.07; 95%CI:1.04–1.11) and extreme heat (RR:1.23; 95% CI: 1.13–1.35). The Southern and Midwest regions were only associ-ated with cold, with higher RR values for the South (extreme cold:1.41; 95%CI: 1.29–1.54); moderate cold: 1.18; 95% CI:1.09-1.27) than for the Midwest (extreme cold:1.27; 95%CI:1.14-1.40; moderate cold:1.13; 95%CI:1.05–1.23). There was no change in the effect of FHS coverage level on the association between temperature and AMI mortal-ity in any large region. Brazil is a country marked by important inequalities between the regions that appear in these results. With climate change and global warming, extreme temperature events are being frequently impacting on population morbidity and mor-tality and demanding measures to reduce this impact. This study shows the effects of temperature on AMI mortality and warns of the need to enable primary care services to address this risk factor.