Worldwide distribution, associated factors, and trends of gallbladder cancer: a global country-level analysis

This study aimed to evaluate the global distribution, associated factors, and epidemiologic trends of gallbladder cancer (GBC) by country, sex, and age groups. The Global Cancer Observatory was interrogated for the disease burden of GBC using age-standardized rates (ASR). The prevalence of different potential risk factors for each country was extracted from Global Health Observatory and their associations with GBC incidence and mortality were examined by linear regression analysis using beta coefficients (β). The Cancer Incidence in Five Continents I-XI and the WHO Mortality database were searched and Average Annual Percent Change (AAPC) was generated from joinpoint regression analysis. The incidence (ASR = 2.3) and mortality (ASR = 1.7) of GBC varied globally in 2018 and were higher in more developed countries and among females. Countries with higher incidence had higher human development index (β_male = 0.37; β_female = 0.27), gross domestic products (β_male = 0.13) and higher prevalence of current smoking (β_female = 0.05), overweight (β_male = 0.02), obesity (β_male = 0.03), and hypercholesterolaemia (β_male = 0.07). Similar patterns of associations were also observed for mortality with an additional association found for diabetes (β_female = 0.07). Although there was an overall decreasing trend in mortality, an increasing trend in incidence was observed among some populations, particularly in males (AAPCs, 8.97 to 1.92) and in younger individuals aged <50 years (AAPCs, 12.02 to 5.66). The incidence of GBC varied between countries and was related to differences in the prevalence of potential risk factors. There was an increasing incidence trend among males and younger individuals. More intensive lifestyle modifications and disease surveillance are recommended for these populations.