Endocrine Abstracts

Objective: Children with malignant disease are at increased risk of bone disorders, cardiovascular disease and further neoplasia. Vitamin D status may influence this risk and so we assessed Vitamin D levels in children with malignant disease undergoing active treatment or surveillance post-therapy.

Study design: This was an outpatient-based cross-sectional study of 60 children with a history of malignancy (cases: median age 11.1 years; range 1.5–24.4 years) and 61 control subjects (median age 8.4 years; range 0.2–18.0 years) who were attending hospital for the management of non-malignant disorders. Serum vitamin D (25OHD), PTH levels and bone biochemistry were determined. Vitamin D status (defined here by 25OHD levels) and its relationship to age, sex, ethnicity, time of sampling and presence of malignant disease was assessed using multiple regression.

Results: Vitamin D status was suboptimal in 62% of cases (25OHD<50 nmol/l). Vitamin D deficiency (defined here as 25OHD<25 nmol/l) was more common in children with malignant disease than controls (21.3% vs 3.3%; P=0.013). Month of sampling (P<0.001), ethnicity (P<0.001), older age (P=0.011) and history of malignancy (P=0.012) were associated with a poorer vitamin D status. Higher PTH levels were associated with significantly lower vitamin D status in controls (r=−0.42; P=<0.01) but not in cases (r=−0.07; P=0.65). The median Body Mass Index in the cases (18.7) was comparable to the controls (18.2).

Conclusions: Vitamin D levels are lower in survivors of childhood cancer in comparison to control children with the majority either insufficient or deficient. This may reflect poor diet, an increased amount of time spent indoors compared to their peers as well as the toxic effects of chemotherapy/radiotherapy. An assessment of Vitamin D status and, where necessary, appropriate supplementation may be of particular value in this group of children.