Gender and Social Disparities in Esophagus Cancer Incidence in Iran, 2003-2009: A Time Trend Province-level Study


Background: Esophagus cancer (EC) is among the five most common cancers in both sexes in Iran, with anincidence rate well above world average. Social rank (SR) of individuals and regions are well-known independentpredictors of EC incidence. The aim of current study was to assess gender and social disparities in EC incidenceacross Iran’s provinces through 2003-2009. Materials and
Methods: Data on distribution of population at provincelevel were obtained from the Statistical Centre of Iran. Age-standardized incidence rates of EC were gatheredfrom the National Cancer Registry. The Human Development Index (HDI) was used to assess the province socialrank. Rate ratios and Kunst and Mackenbach relative indices of inequality (RIIKM) were used to assess genderand social inequalities, respectively. Annual percentage change (APC) was calculated using joinpoint regression.
Results: EC incidence rate increased 4.6% and 6.5% per year among females and males, respectively. There wereno gender disparities in EC incidence over the study period. There were substantial social disparities in favorof better-off provinces in Iran. These social disparities were generally the same between males and females andwere stable over the study period.
Conclusions: The results showed an inverse association between the provinces’social rank and EC incidence rate in Iran. In addition, I found that, in contrast with international trends, womenare at the same risk of EC as men in Iran. Further investigations are needed to explain these disparities in ECincidence across the provinces.