Geographic variation of gallbladder cancer mortality and risk factors in Chile: A population‐based ecologic study

Abstract

Chile's gallbladder cancer rates are among the highest in the world, being the leading cause of cancer deaths among Chilean women. To provide insights into the etiology of gallbladder cancer, we conducted an ecologic study examining the geographical variation of gallbladder cancer and several putative risk factors. The relative risk of dying from gallbladder cancer between 1985 and 2003 was estimated for each of the 333 Chilean counties, using a hierarchical Poisson regression model, adjusting for age, sex and geographical location. The risk of gallbladder cancer mortality was analyzed in relation to region, poverty, Amerindian (Mapuche) population, typhoid fever and access to cholecystectomy, using logistic regression analysis. There were 27,183 gallbladder cancer deaths, with age and sex-adjusted county mortality rates ranging from 8.2 to 12.4 per 100,000 inhabitants. Rates were highest in inland and southern regions. Compared to the northerncoast, the northern-inland region had a 10-fold risk (95% of confidence interval (95% CI): 2.4-42.2) and the southern-inland region had a 26-fold risk (95% CI: 6.0-114.2). Independent of region, other risk factors for gallbladder cancer included a high Mapuche population (Odds ratio (OR):3.9, 95% CI 1.8-8.7), high typhoid fever incidence (OR:2.9, 95% CI 1.2-6.9), high poverty (OR:5.1, 95% CI 1.6-15.9), low access to cholecystectomy (OR:3.9, 95% CI 1.5-10.1), low access to hospital care (OR:14.2, 95% CI 4.2-48.7) and high urbanization (OR:8.0, 95% CI 3.4-18.7). Our results suggest that gallbladder cancer in Chile may be related to both genetic factors and poor living conditions. Future analytic studies are needed to further clarify the role of these factors in gallbladder cancer etiology.

Cáncer de vesícula biliar en Chile y factores nutricionales de riesgo

“…Los principales factores de riesgo que han sido estudiados en relación al cáncer en general son el tabaco, alcohol, agentes infecciosos, radiación ionizante, agentes químicos, patrones dietarios y la obesidad (16)(17)(18)(19). Específicamente para el CVB, se han identificado como componentes de riesgo ser de sexo femenino, colelitiasis, obesidad, etnia, inflamación crónica, historia de enfermedades infecciones como H. pylori e historia familiar de cáncer (6,15).…”

“…La incidencia es baja en la población caucásica de los Estados Unidos y en la mayoría de los países de Europa occidental, en cambio es muy alta en Asía y Latinoamérica (12,16,17). La etnia mapuche presenta la tasa más alta de vesícula biliar a nivel mundial (25,26).…”

“…El estudio realizado por Bertran (8) señala que la población de la ciudad de Valdivia, Chile, manifestó una incidencia cruda de cán-cer de vesícula de 17,8 por 100.000 habitantes y un SIR ajustado por edad de 17,5 (CI 95%; 15,[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]4). En este estudio, el 76% de los casos fueron mujeres, con una incidencia cruda de 26,7 y un SIR de 24,3 (CI 95%; 21,2-27,4).…”

Emphasizing unique strengths and eliminating redundancy for research in low‐income and middle‐income countries: Lessons from a South American country

“…Consider a unique epidemiological fact about Chile: to our knowledge, the incidence of gallbladder cancer in Chile is the highest in the world, and is many times higher than that of comparable and neighboring nations. 7 Gallbladder cancer in Chile is one of the leading causes of cancer death among women. 7 For this reason, studying potential reasons why the cancer is uniquely prevalent, as well as exploring its molecular characteristics, are inherently high-value research efforts.…”

“…7 Gallbladder cancer in Chile is one of the leading causes of cancer death among women. 7 For this reason, studying potential reasons why the cancer is uniquely prevalent, as well as exploring its molecular characteristics, are inherently high-value research efforts.…”