Nutritional status, hospitalization and mortality among patients with sickle cell anemia in Tanzania

Abstract

Background: Reduced growth is common in children with sickle cell anemia, but few data exist on associations with long-term clinical course. Our objective was to determine the prevalence of malnutrition at enrollment into a hospital-based cohort and whether poor nutritional status predicted morbidity and mortality within an urban cohort of Tanzanian sickle cell anemia patients.

Design and methods: Anthropometry was conducted at enrollment into the sickle cell anemia cohort (n=1,618; ages 0.5-48 years) and in controls who attended screening (siblings, walk-ins and referrals) but who were found not to have sickle cell anemia (n=717; ages 0.5-64 years). Prospective surveillance recorded hospitalization at Muhimbili National Hospital and mortality between March 2004 and September 2009.

Results: Sickle cell anemia was associated with stunting (OR=1.92, P<0.001, 36.2%) and wasting (OR=1.66, P=0.002, 18.4%). The greatest growth deficits were observed in adolescents and in boys. Independent of age and sex, lower hemoglobin concentration was associated with increased odds of malnutrition in sickle cell patients. Of the 1,041 sickle cell anemia patients with a body mass index z-score at enrollment, 92% were followed up until September 2009 (n=908) or death (n=50). Body mass index and weight-for-age z-score predicted hospitalization (hazard ratio [HZR]=0.90, P=0.04 and HZR=0.88, P=0.02) but height-for-age z-score did not (HZR=0.93, NS). The mortality rate of 2.5 per 100 person-years was not associated with any of the anthropometric measures.

Conclusions: In this non-birth-cohort of sickle cell anemia with significant associated undernutrition, wasting predicted an increased risk of hospital admission. Targeted nutritional interventions should prioritize treatment and prevention of wasting.

Figure 1.

Height, weight and BMI centile plots for SCA compared to UK reference data. (A, C) and (E) are for females and (B, D) and (F) for males. Red dotted lines are the 95^th, median and 5^th centile curves for UK reference data (1990); solid blue lines represent the 95^th, median and 5^th centile curves for the Tanzanian SCA population. UK reference curves were extrapolated at the same level after the maximum age available of 23 years.