Behavior-related risk factors for opisthorchiasis-associated cholangiocarcinoma among rural people living along the mekong river in five greater mekong subregion countries.

Opisthorchiasis-associated cholangiocarcinoma (OV-CCA) is a major public health problem in Greater Mekong Subregion (GMS) Countries, the poorest region in Asia. People in this region have similar traditions or respect the same religion. There is no difference in lifestyle and food culture. Excluding Thailand, publications on risk factors for OV-CCA from the GMS Countries are few, especially data on behavioral risk factors for OV-CCA. Therefore, this study aimed to assess the behavior-related risk factors and to compare the risk of OV-CCA among rural people living along the Mekong River in five GMS countries. It was a cross-sectional analytic study during June and October 2017. All participants with informed consent completed the questionnaires. Descriptive statistics were used to describe the prevalence of risk factors. Odds ratio with 95% confidence intervals were used to compare the risk of OV-CCA. It was found that there were more drinkers than non-drinkers in all areas, except in Vietnam. The highest history of liver fluke infection was found in Cambodia. Praziquantel use and consumption of raw freshwater fish dishes were mostly found in Lao PDR. The highest consumption of nitrosamine-contaminated foodstuffs was found in Ubon Ratchathani, Thailand. The spatial comparison of OV-CCA risk showed that Lao PDR and Ubon Ratchathani were two risk areas when compared to Tachileik, Myanmar (a reference area). This study provided the behavior-related risk factors for OV-CCA among people in five GMS Countries which would be a major jigsaw puzzle leading to proactive surveillance for OV-CCA prevention in the future.