Body mass index and annual increase of body mass index in long-term childhood cancer survivors; Relationship to treatment

Purpose: Evaluation of body mass index (BMI) at final height (FH) and annual BMI increase in adult childhood cancer survivors (CCS) after treatment with anthracyclines, platinum, and/or radiotherapy. Methods: BMI (weight/height2) was calculated retrospectively from diagnosis until FH. The prevalence of underweight (BMI < 18.5 kg/m ²) and overweight (BMI ≥ 25 kg/m ²)/obesity (BMI ≥ 30 kg/m ²) at FH was compared with age-matched controls. The association between underweight/ overweight at FH and treatment was assessed by multivariate logistic regression. Annual BMI increase after treatment was assessed by multilevel analysis. Analyses were adjusted for age and underweight/overweight at diagnosis, and age at FH. Results: At FH the prevalence of overweight had not increased, while CCS experienced more underweight as compared to controls (14% vs. 4%, P < 0.001). Overweight at FH was associated with cranial/craniospinal radiotherapy (CRT; OR, 2.23; 95% CI, 1.17-4.26) and underweight at FH with anthracyclines > 300 mg/m ² (OR, 2.84; 95% CI, 1.33-6.06). Annual BMI increase was +0.47 (0.34-0.60) kg/m ²/year. In CCS, the annual BMI increase was greater in those with CRT ≥ 30 Gy as compared with those with less or no CRT (+0.15 kg/m ²/year [0.04-0.25 kg/m ²/year], P = 0.008) and smaller in those with a higher cumulative anthracycline dose (-0.03 kg/m ²/year [-0.05 to -0.0005 kg/m ²/year] per 100 mg/m ², P = 0.046). Conclusions: After treatment with anthracyclines, platinum, and/or radiotherapy, CRT-treated survivors have more overweight at FH, and a greater annual BMI increase, while anthracycline-treated survivors have more underweight at FH and a lower annual BMI increase.