Volume 72, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


has been related to anemia, but the mechanisms mediating this relationship remain unresolved. The primary objective of this study was to assess the role of occult blood loss in mediating -associated anemia after adjusting for age, sex, socioeconomic status (SES), and other helminth infections. The secondary objective was to identify intensity categories of risk for occult blood loss for and hookworm after adjustment for the presence of other helminth infections. The role of occult blood loss in mediating -associated anemia was studied cross-sectionally in 729 individuals 8–30 years old in Leyte, The Philippines. Three stool specimens were examined in duplicate for helminth eggs. Hemoglobin, fecal occult blood loss, and anemia were measured and related to the presence and intensity of helminths. Multivariate models were made to adjust for confounding by other helminths and SES. In multivariate models, hemoglobin significantly decreased with increasing infection intensity of , hookworm, and ( < 0.0031, < 0.0001, and < 0.0001, respectively). Individuals with higher intensities and were significantly more likely to be fecal occult positive (odds ratio [OR] = 3.54; = 0.008 and OR = 2.68; = 0.013, respectively), although this was not true for individuals with hookworm. Additionally, individuals with higher intensities of , hookworm, and were all more likely to be anemic (OR = 3.7, = 0.0002; OR = 5.3, = 0.0003; and OR = 1.6, = 0.021, respectively). It is likely that occult blood loss plays a role only at heavier intensity infections and some other mechanism, such as anemia of inflammation, may be contributing to anemia.


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  • Received : 10 May 2004
  • Accepted : 07 Jul 2004

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