Use of Diet History in the Screening of Iron Deficiency

Abstract

Objective. To determine the relationship between diet history and microcytic anemia, a proxy for iron deficiency, and the utility of a brief dietary history in screening for microcytic anemia. Design. Cross-sectional study based on review of clinical records. Setting. Urban academic primary care clinic. Subjects. A total of 305 healthy, African-American inner-city children, presenting for well child care at 15 to 60 months of age. Children with recent minor illness or medicinal iron intake, hemoglobinopathies, chronic illnesses, failure to thrive, or elevated lead levels were excluded. Method. A brief dietary history was taken in the course of primary care visits. Dietary deficiency was defined as: (1) less than five servings each of meat, grains, vegetables, and fruit per week; (2) more than 16 oz of milk per day; or (3) daily intake of fatty snacks, sweets, or more than 16 oz of soft drink. Hematologic indices were obtained. Results. The prevalence of microcytic anemia (hemoglobin, < 11 g/dL; mean corpuscular volume, <73 fL) was 8% (24 of 305). The prevalence of low hemoglobin (<11 g/dL) with or without microcytosis was 12% (38 of 305). Dietary deficiency was associated with microcytic anemia (x2 = 26.8). As a screening test for microcytic anemia, dietary deficiency had a sensitivity of 71% (17 of 24), specificity of 79% (222 of 281), and negative predictive value of 97% (222 of 229). Conclusion. Microcytic anemia was associated with a deficient diet among low-income African-American children. A brief dietary history correctly identified children at low risk for microcytic anemia 97% of the time.