CONTEXT:

An important indicator of nutritional status within a pediatric population is the anemia prevalence rate. Limited national data are available regarding trends in anemia prevalence among non-low-income children.

OBJECTIVE:

To determine the prevalence of anemia over time among children enrolled in a health maintenance organization (HMO).

DESIGN:

Trend analysis, adjusted for clinical site, age group, sex, race/ethnicity, Medicaid insurance, and testing frequency within each year, and accounting for repeated observations of individual children across different years.

SETTING:

Massachusetts HMO.

PARTICIPANTS:

72,729 children aged 6-59.9 months seen at 126,695 well-child visits from 1987 to 2001.

MAIN OUTCOME:

Anemia prevalence by hemoglobin level.

RESULTS:

The observed prevalence of anemia was 8.9%, and was higher among younger children, blacks, boys, and those with Medicaid insurance. While the unadjusted anemia rate among children tested increased from 9.9% in 1987 to 11% in 2001, the proportion of children who were tested for anemia declined from 55% to 45% during the study period. After adjustment for demographics and testing frequency, the odds of anemia decreased over time (odds ratio 0.84, 95% confidence interval 0.76-0.93, per decade). Predicted anemia prevalence among those tested decreased from 8.9% in 1987 to 7.1% in 2001.

CONCLUSIONS:

Anemia was less prevalent in this HMO population than has been reported in low-income children. After adjustment for testing frequency, the odds of anemia declined over time. As testing practices change to target children at higher risk, trend analyses should account for differences in screening rates over time. The computerized medical records of large health systems may serve as a valuable tool for nutritional surveillance among non low-income populations.