Iniquidades na mortalidade em 15 anos de seguimento do Elsa-Brasil: posição socioeconômica no curso de vida, mobilidade social e status social subjetivo

Abstract

Despite advances in global health in recent years, with increased life expectancy and reduced mortality rates, health inequalities persist, even in wealthy countries with universal healthcare systems. However, the mechanisms involved in this process remain unclear. In this context, this thesis aims in article 01 to investigate whether socioeconomic position (SEP) at each stage of the life course, the accumulation of negative socioeconomic exposures, and unfavorable intergenerational social mobility are associated with overall mortality over a 15 years follow-up period in the ELSA-Brasil study; and in article 02 to investigate whether subjective social status (SSS) in each of the three dimensions assessed (society, neighborhood, and work) is associated with cardiovascular disease (CVD) mortality and overall mortality over a 15 years follow-up period in the ELSA-Brasil study. All participants who attended the first visit of ELSA-Brasil and had valid data for socioeconomic position, subjective social status, CVD mortality and overall mortality were eligible for the analysis. The outcome variable for both articles was the time elapsed from study entry to death or censorship. The explanatory variables for article 01 were childhood SEP (maternal education), youth SEP (household head`s socio-occupational class), adult SEP (participant's education and socio-occupational class), accumulation of low SEP exposures, and intergenerational social mobility. Cox proportional hazards models adjusted for sociodemographic characteristics were used to estimate the associations. As a result of article 1, we found a mortality rate of 4.9/1,000 person-years, being higher in men, older people, Black people, and those with low SEP. Low SEP in childhood (HR: 1.41; 95% CI: 1.12-1.77), youth (HR: 1.39; 95% CI: 1.15-1.67) and adulthood - education – (HR: 2.37; 95% CI: 1.89-2.97) remained associated with higher mortality, even after considering sociodemographic characteristics. A higher accumulation of low SEP (HR: 2.02; 95% CI: 1.64-2.48, 4th quartile vs. 1st) and downward and stable low educational and socio-occupational trajectories were also associated with higher mortality. Additionally, upward socio-occupational trajectory increased the risk of death to a lesser extent (HR: 1.38; 95% CI: 1.11-1.71). We tested and did not find a multiplicative interaction between SEP and race/color on the risk of death. For article 2, the explanatory variable was subjective social status, obtained through the MacArthur scale. Cox proportional hazards models adjusted for sociodemographic characteristics and socio-occupational class were used to estimate the associations. The CVD mortality rate was 1.58/1,000 person-years. For all causes, the rate was 5.0/1,000 person-years, being higher in men, older people, Black and Brown individuals, and those with lower SSS in both cases. After adjustment for race/color, the association between SSS and CVD mortality was no longer maintained. For all-cause mortality, the association remained, even after considering race/color and socio-occupational class in the fully adjusted model for the societal scale (HR: 1.37; 95% CI: 1.03-1.83). We found no multiplicative SSS-sex or SSS-race/color interaction on the risk of dying from CVD or all causes. Our findings suggest that socioeconomic disadvantages at different periods of the life course, the accumulation of negative social experiences, and unfavorable intergenerational social mobility increase the risk of death. SSS also proved to be an important predictor of all-cause mortality. Interestingly, race/color explained the entire association between SSS and CVD mortality. This work offers a valuable contribution to the field of public health, confirming the persistence and impact of social inequities on mortality in Brazil and highlighting the multifaceted role of socioeconomic position and perceived social status. Our results are a call to action to address the structural roots of inequalities and implement policies that promote a less unequal society.