AN ASSOCIATION OF APLASTIC-ANEMIA IN THAILAND WITH LOW SOCIOECONOMIC-STATUS

The relationship of socioeconomic status to the risk of aplastic anaem ia was evaluated in a case-control study conducted in Bangkok and two rural regions of Thailand (Khonkaen and Songkla). Among 152 cases and 921 controls there were significant trends of increasing risk with dec reasing years of education (P = 0.01) and total household income (P = 0.0001), after control for confounding. The relative risk estimate for those with monthly incomes of <1500 baht (about $60 U.S.) was 3.9 (95 % confidence interval 2.1-7.3) compared to those with monthly incomes of at least 5000 baht (about $200). The pattern of increasing risk wit h decreasing income was observed in all three regions, with significan t trends in Bangkok (P = 0.004) and Khonkaen (P = 0.003). This finding may partly explain the high incidence of aplastic anaemia in Thailand . Low socioeconomic status may be a surrogate for one or more environm ental factors that could cause aplastic anaemia, such as infectious pa thogens or toxic exposures.