Social determinants of cancer incidence and mortality around the world: an ecological study

Cancer continues to be a leading cause of mortality and morbidity the world over. While the incidence of cancer is projected to increase by 70% over the next two decades, some research findings suggest a disproportionate distribution of new cancer cases and attendant fatalities across certain regions of the world, with poor and lower income countries worse affected at a time when advances in cancer research, medical technology, and drug development are giving rise to better cancer survival in developed countries. In this study, the role of selected social determinants of health in gauging cancer outcomes relative to incidence across various countries in different regions of the world was explored. The results indicated that the education index, income index, Gini coefficient, availability of cancer control policies and programs, as well as health system performance have an association with and are good predictors of the mortality to incidence ratio (MIR) of lung, breast, cervical, and colorectal cancers. In other words, populations with better education, higher incomes and lower inequalities, active cancer control policies and programs and high performing health systems have better cancer outcomes as reflected in lower MIRs relative to other populations.