Spatial Structure of Breast Cancer Using Poisson Generalized Linear mixed model in Iran (2004-9)

Introduction & Aim: Breast cancer is one of the most common diseases in women, and more than other cancers leads to deaths in woman. The increasing trend of breast cancer in Iran is the necessity of studies on this field. The purpose of this study is to determine the spatial structure associated with the incidence of breast cancer and to identify regions with high incidence of breast cancer. Methods: This ecological study consists of all breast cancer patients registered in Iran in the period of 2004 to 2009. Consumption of fruits and vegetables, physical activity, overweight or obesity and Human Development Index (HDI) are the factors that have been investigated in this study. To analysis the data, routine and spatial Poisson Generalized Linear Mixed Models (GLMM) was used. Results: In both routine and spatial Poisson s GLMMs, the direct and significant relationship between incidence of breast cancer and HDI was found. In addition, the overweight or obesity is directly related to the incidence of breast cancer in spatial Poisson s GLMM. In the correlation structure of BYM in the spatial Poisson s GLMM, Gilan and East Azarbaijan provinces have the highest and Kohkiluyeh-Boyer Ahmad province has the lowest risk of breast cancer. Conclusions: The distribution of breast cancer in Iran has a spatial structure. That is, the adjacent provinces have similar incidences of this disease.