Anemia among adolescent females in urban public health clinics: Prevalence, incidence, and the need for screening

Anemia is one of the most common abnormalities encountered in general pediatric practices. Anemia is one of the five most prevalent chronic conditions in African-American females under the age of 17 years. Little is known about the prevalence of anemia in inner-city patient populations. Few studies have looked at the incidence of anemia over time, or at predictors of incident anemia. A retrospective cohort study was conducted using medical records from the 8 neighborhood health centers operated by the Philadelphia Department of Public Health. The patient population is overwhelmingly low-income (97% report household incomes below 200% of the federal poverty limit), and most are either on Medicaid or uninsured. Females who had a well-child visit and had a CBC test ordered between March 1, 2005 and September 30, 2006, and were ages 14-17 at their last visit within that period, were identified from the PHCC information system. All 314 eligible patients were selected for chart review. Eighty-four percent of the sample was African-American, 5% was Hispanic, 5% Asian, 3% white and 2% other. Because studies have indicated that normative hemoglobin values are 0.5 g/dL lower in African Americans than in non-Hispanic whites, we used hemoglobin (Hgb) level of 11.5 g/dL as the cut off for anemia. Baseline prevalence of anemia, defined as Hgb < 11.5 g/dL, was 13.4% at the first CBC age 12 or above. Among those who were not anemic at baseline and had a subsequent CBC, 11.8% developed anemia during follow-up, at an incidence rate of 3.3% (95% confidence interval 2.2%-4.7%) per year. Baseline Hgb was strongly predictive of anemia incidence. Incidence ranged from 2% among girls with baseline Hgb ≥ 13.0 g/dL to 39% among those with baseline Hgb 11.5-11.9 g/dL. Overall cumulative prevalence of anemia (Hgb < 11.5 g/dL at any point during followup) was 23.6%. Anemia was far more prevalent in this inner-city patient population than the 2% prevalence found in national data for adolescent girls. We have not located prior estimates of anemia incidence in non-pregnant inner-city adolescent females, but incidence is clearly substantial in this population. The American Academy of Pediatrics recently changed its recommendation that menstruating adolescent girls be screened for anemia during all routine physical examinations to an annual risk assessment. Other professional organizations have not recommended routine screening of adolescents. Routine and repeated screening may be appropriate in vulnerable populations, especially for those with baseline Hgb < 13.0 g/dL.