Malnutrition at diagnosis of acute lymphoblastic leukemia negatively affects survival in children

Background: Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer worldwide.Nutritional status plays a crucial role and may increase mortality risk; however, this area has not been completely addressed.We aimed to evaluate nutritional status using the body mass index Z-score (Z-BMI) at diagnosis, induction, and surveillance, and its impact on mortality in patients with ALL.Methods: We conducted a retrospective cohort study of patients treated between 2015 and 2020, aged 2-18 years, without other chronic comorbidities.The exposure was nutritional status, estimated with Z-BMI.The primary outcome was all-cause mortality.Results: Among 94 patients (male: 65% [n = 61]; median age: 6 years [IQR 3.5-10]), 79 (84%) were alive and 15 (16%) died during follow-up.Kaplan-Meier curves showed that patients with normal weight at diagnosis had higher survival probability, whereas those with malnutrition had the lowest survival (p = 0.045).In an adjusted Cox regression model, patients with overweight/obesity and malnutrition at diagnosis had 4.95 times (95% CI: 0.20-122; p = 0.30) and 12.5 times (95% CI: 1.25-126; p = 0.032) higher risk of mortality, respectively.Conclusions: Nutritional status at diagnosis is a predictor of mortality in children with ALL, underscoring the need for early, multidisciplinary interventions.