Abstract P1-09-23: Disparities in female breast cancer mortality rates between urban centers and rural areas of Brazil: Ecological time series study

Abstract

Abstract Background: Social and regional inequalities in Brazil such as delayed diagnosis and the lack of an organized healthcare system, which hamper access to treatment, predominantly affect women from lower socioeconomic strata with breast cancer. Residents in urban centers are known to have a more favorable socioeconomic status and better access to medical care. Aim: To evaluate mortality trends in female breast cancer in urban centers and rural areas of the Brazilian states between 1980 and 2010. Methods: This was an ecological time series study, using the number of breast cancer deaths in Brazil was obtained from the Nationwide Mortality Database (SIM/WHO), and demographic database were obtained from the Brazilian Institute of Geography and Statistics (IBGE/WHO). A systematic analysis of temporal trends in the mortality rate was performed by joinpoint regression. To describe the trend in each period, the annual percent change (APC) was obtained, together with the relevant 95% confidence intervals. P-values < 0.05 were considered statistically significant. Results: In urban centers in southern Brazil, mortality rates were almost 20 times higher than those in the north of the country. A declining trend in breast cancer mortality was found in some urban centers: Porto Alegre (-1.6%; -2.4 to -0.7; p<0.01); Rio de Janeiro (-0.9%; -1.4 to -0.4; p<0.01); São Paulo (-1.7%; -2.6 to -0.9; p<0.01); Belo Horizonte (-1.2%; -2.0 to -0.4; p = 0.01) and Recife (-0.9%; -1.7 to -0.1; p = 0.03). However, increases were found in other urban centers: Fortaleza (0.5%; 0.1–0.9; p = 0.02), Belém (0.8%; 0.2–1.5; p = 0.01), João Pessoa (1.6%; 0.7–2.6; p<0.01), Teresina (4.6%; 1.2–8.2; p = 0.01) and Porto Velho (9.0%; 3.8–14.6; p<0.01). A reduction occurred in rural areas of the state of São Paulo (-2.8%; 95%CI: -4.4 to -1.3; p<0.01). However, increases were found in most other rural areas in all the different states of the country, the worst being in Maranhão (17.6%; 95%CI: 9.2–26.7; p<0.01), Paraíba (14.5%; 10.0–19.2; p<0.01), Piauí (10.0%; 8.1–13.7; p<0.01) and Alagoas (10.8%; 7.1–14.6; p<0.01). In the majority of rural areas of Brazil, mortality from female breast cancer continues to rise, with the exception of some areas in the southern part of the country. Conclusion: Considerable disparity was found in female breast cancer mortality rates between the urban centers and rural areas of Brazil. These findings are in line with the socioeconomic inequalities present in the country. Another possible reason for the disparity found in breast cancer mortality may be a consequence of the variations in women's exposure to risk factors and of diagnostic practices. In the majority of the Brazilian states, mortality rates are lower in rural regions, a finding that could be attributed to the low incidence of breast cancer in rural areas or to the presence of protective factors such as multiparity, breastfeeding and the young age of women at the birth of their first child, occurrences that are common in rural areas of Brazil. The results presented here on mortality rates of female breast cancer in the urban and rural areas of Brazil may be considered an indicator of breast cancer control. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-09-23.