Bone Mineral Density After Contemporary Treatment for Acute Lymphoblastic Leukaemia: A Matched Cross‐Sectional Study

ABSTRACT Background Reduced bone mineral density (BMD) has been reported in survivors of childhood and young adult acute lymphoblastic leukaemia (ALL); however, data from cohorts treated with contemporary protocols and including matched controls remain limited. Procedure In this population‐based matched cross‐sectional study, we used data from the Danish ALL‐STAR cohort, comprising ALL survivors diagnosed between 2008 and 2019 at 1–45 years of age and treated according to the NOPHO ALL2008 protocol, and age‐ and sex‐frequency matched controls. Participants were evaluated at least 1 year after completion of therapy and underwent dual‐energy x‐ray absorptiometry between 2019 and 2024. BMD was adjusted for sex, age and height and compared with that of matched controls. Results The study included 298 ALL survivors and 346 matched controls. Median age at follow‐up was 14.1 years, and the median time since diagnosis was 6.9 years. The greatest deficits in adjusted BMD were observed at hip sites, particularly among high‐risk–treated survivors, with adjusted mean values of 91.2% (95% CI 88.2–94.4) at the femoral neck, 90.1% (95% CI 86.9–93.3) at the total hip, and 90.3% (95% CI 87.0–93.7) at the trochanter. Increasing time since diagnosis was associated with partial normalisation of BMD relative to controls in the standard‐ and intermediate‐risk groups, a pattern not observed among high‐risk‐treated survivors. Conclusions Persistent BMD deficits among survivors treated with high‐risk regimens, without evidence of the partial normalisation observed in the standard‐ and intermediate‐risk groups, underscore the need for long‐term monitoring of skeletal health in this subgroup.