Breast cancer mortality trends and patterns in Cordoba, Argentina 1986-2006

To estimate the mortality trends and spatial patterns for breast cancer in Córdoba (Argentina) in the period 1986-2006 taking into account age, calendar year, and birth cohort effects. Mortality data were provided by the Department of Statistics, Ministry of Health of Córdoba. Time trends in breast cancer mortality were analyzed using joinpoint analysis and age-period-cohort models. A random-intercept log-linear model was also used to assess the spatial pattern. Breast cancer age standardized mortality rates rose by 1.4% (95% confidence interval 0.2-2.6) per year from 1986 to 1997, and thereafter both breast and total cancer rates declined [-2.5% (-4 to -1.0) and -1.6% (-2.3 to -0.8), respectively]. In age-specific analysis the decline was mainly at age 20-49 years [-2.4% (-4 to -0.9)]. Rates over most recent calendar years decreased, mainly in the most urbanized districts. Age-period-cohort models for Córdoba province and Córdoba Capital showed a favorable cohort effect for generations born after 1955. A decreasing trend in breast cancer mortality was found in Córdoba, especially at younger ages and in most urbanized areas. This could be attributed to some unidentified favorable factors in generations born after 1955.