Anemia and Elevated Lead Levels in Underimmunized Inner-city Children

Objective. Underimmunized children are less frequently screened for anemia and elevated lead levels than those who are up-to-date (UTD). However, the association between underimmunization and actual disease (hemoglobin [Hgb] <11 g/dL or blood lead level [PbB] ≥10 μg/dL) has not been reported. The objective of this study was to evaluate the association between underimmunization, anemia, and elevated lead levels among children attending an inner-city clinic. Study Design. Data from a computer-based immunization tracking system were integrated with primary care-based laboratory data. Cross-sectional data for immunization coverage, anemia, and elevated lead levels were evaluated for children who were 1, 2, 3, and 4 years of age. The first Hgb or PbB values obtained within 6 months of the child's birthday were used. Setting. An inner-city hospital-affiliated pediatric primary care center. Patients. A child was considered to be a pediatric primary care center patient if he/she had at least 3 immunizations in the immunization tracking system and at least 1 Hgb or PbB screening test during February 1993 through February 1996. Results. A total of 4045 Hgb tests from 2672 children were available for analysis (1198, 1102, 945, and 800 at 1, 2, 3, and 4 years of age, respectively). Anemia was common during the first 4 years of life (21.2%, 15.8%, 11.0%, and 10.3% at 1, 2, 3, and 4 years of age, respectively). At 2 and 3 years of age, underimmunized children were significantly more likely to be anemic compared with UTD children (relative risk [RR] = 1.49, 95% confidence interval [CI] = 1.24–1.79 at 2 years of age; RR = 1.43, 95% CI = 1.12–1.83 at 3 years of age). Underimmunized children with anemia at 1 year of age were less likely than UTD children to resolve their anemia by 2 years of age (52.5% vs 20.8%, RR = 2.39; 95% CI = 1.47–3.87). Underimmunized children were also significantly more likely to have elevated lead levels at 2 years of age (RR = 1.24; 95% CI = 1.03–1.5). Conclusion. Underimmunized children in the inner city are at especially high risk for anemia and elevated lead levels. These children need routine preventive health services, as well as immunization. Integrating laboratory screening data with immunization tracking systems would be an important step toward improving the health of inner-city children.