Desigualdade social intraurbana, prevalência e incidência de diabetes tipo II no ELSA-BRASIL: uma análise espacial

Abstract

Introduction: Type 2 diabetes mellitus (DM 2) is an important public health problem worldwide, being a disease strongly associated with unhealthy lifestyle habits. Furthermore, its occurrence occurs with unequal magnitude depending on socioeconomic and environmental conditions. However, studies on this last topic considering geographic coordinates of the outcomes of interest have been incipient, particularly with data from the Brazilian population. Objectives: 1. General: Model the spatial risk of the occurrence of DM2 associated with individual and socioeconomic variables of the neighborhood environment of participants in the Longitudinal Study of Adult Health (ELSA-Brazil); 2. Specific: Article 1 – Analyze the spatial aggregation of prevalent cases of DM2, associating this outcome with the individual and socioeconomic characteristics of the participants' neighborhood environment; Article 2 – Analyze the geographic grouping of incident cases of DM2, associating this outcome with the individual and socioeconomic characteristics of the participants' neighborhood environment. Methods: This is an observational and analytical epidemiological study, carried out in two stages with the ELSA-Brasil database. In stage 1 (Article 1), a cross-sectional study was conducted with 4,335 participants (2,486 from the city of Belo Horizonte, Minas Gerais and 1,849 from the city of Salvador, Bahia), using baseline data collected between 2008 and 2010 In stage 2 (Article 2), a longitudinal study was conducted with 3,877 participants (2,427 from the city of Belo Horizonte, Minas Gerais and 1,450 from the city of Salvador, Bahia), using data from three waves: baseline; follow-up 1, collected between 2012 and 2014; follow-up 2, collected between 2017 and 2019. In both stages, the presence of DM2 was considered when participants were diagnosed based on the following criteria: fasting blood glucose ≥ 126 mg/dL (7.0 mmol/L) or oral glucose tolerance test ≥ 200 mg/dL (11.1 mmol/L) or glycated hemoglobin ≥ 6.5% (48 mmol/L) or use of blood glucose-lowering medication or self-reported diagnosis of DM2. In stage 2, as this was an incidence study, participants with DM2 diagnosed at baseline were excluded. The socioeconomic characteristics of the participants' neighborhood were obtained from the 2010 Brazilian Demographic Census. Data analyzes were conducted with the statistical software R, at a significance level of 5%. Initially, the areas of special aggregation of prevalent cases of DM2 were detected with the SaTScanTM method and, to identify the individual and socioeconomic characteristics of the participants' neighborhood environment associated with these areas, the logistic regression technique was used (Article 1) . Furthermore, the risk of greater geographic clustering of incident DM2 cases was estimated by spatiotemporal modeling using survival analysis methods with spatial fragility (Article 2). Results: Article 1 - A total of 336 and 343 participants had DM2 in Belo Horizonte (prevalence = 13.5%) and Salvador (prevalence = 18.5%), respectively. Two areas with a high chance of DM2 aggregation were identified in the Northeast region of Belo Horizonte and the North region of Salvador. In the latter municipality, an area with a low chance of DM2 aggregation was also identified, located in the South (coastal) region. In both cities, participants who lived in the area with a high chance of DM2 aggregation were more likely to report brown or black skin color, low level of education and occupation of manual work; these were also considered low-income areas. On the other hand, participants from the area with a low chance of DM2 aggregation in Salvador were less likely to be mixed race or black and to have university degrees; this was considered a high-income area. Article 2 – In Belo Horizonte, after a median of 11.3 years of follow-up (25,396 person-years), 316 incident cases of DM2 were recorded (12.4 cases/1,000 person-years). In Salvador, after a median of 11.8 years of follow-up (15,226 person-years), 222 incident cases of DM2 were recorded (14.6 cases/1,000 person-years). The regions of the municipalities of Belo Horizonte (Center-South) and Salvador (Coast) were those with the lowest risk of clustering incident cases of DM2. On the other hand, the regions of the municipalities of Belo Horizonte (North and Northeast) and Salvador (Northeast) were those with the highest risk of clustering incident cases of DM2. Furthermore, in Belo Horizonte, age and neighborhood income were associated, respectively, with a shorter and longer average incidence of DM2. Conclusions: High individual social vulnerability or the neighborhood environment was shown to be associated in areas with greater chances of aggregation of prevalent cases of DM2 and areas with greater risk of clustering of incident cases of the disease in the municipalities studied. Therefore, actions to combat poverty and improve socioeconomic conditions in cities are important preventive measures against DM2