Obesity and hypertension among children after treatment for acute lymphoblastic leukemia

BACKGROUND: The purpose was to determine the prevalence and treatment-related risk factors for obesity and hypertension among childhood acute lymphoblastic leukemia (ALL) survivors treated with contemporary therapy. METHODS: In a single-center longitudinal study, serial body mass indices (BMI) and blood pressure (BP) measurements of children ages 2-20 at time of ALL diagnosis and enrolled on pediatric cooperative group trials from 1993-2003 were abstracted from medical records and converted to population-referenced z-scores. RESULTS: Among 165 study participants, BMI z-scores increased significantly between diagnosis (median age 4.8 years) and therapy completion. At the end of therapy, 17.0% of survivors were overweight (BMI of 25-29, or 85-94% for age), 21.2% were obese (BMI >or=30, or >or=95% for age), and 15.3% had BP meeting stage 1+ hypertension thresholds (systolic or diastolic BP >or=140/90 mm Hg, or 95% for age and height plus 5 mm Hg). These proportions were found to be unchanged 2-3 years later. In multivariate analysis, the highest level of corticosteroid exposure was associated with both obesity (odds ratio OR] 6.0; 95% confidence interval 95% CI], 1.2-28.5) as well as stage 1+ hypertension (OR 2.4; 95% CI, 1.2-5.1) compared with the lowest level. Females also were more likely to have increased BMI and elevated BP compared with males. Treatment intensity and cranial radiotherapy were not found to be associated with BMI or BP changes. CONCLUSIONS: Despite reductions in the use of cranial radiotherapy, contemporary childhood survivors of ALL remain at an increased risk of obesity and hypertension at least several years after the completion of treatment, with those exposed to higher doses of corticosteroids at greater risk.