Safety and effectiveness of stoss therapy in children with vitamin D deficiency

Aim: Paediatric vitamin D (25-hydroxyvitamin D (25OHD)) deficiency can lead to nutritional rickets and extra-skeletal complications. Compliance with daily therapy can be difficult, making high-dose, short-term vitamin D (stoss) therapy attractive to correct vitamin D deficiency. We compared the effectiveness and safety of standard versus stoss therapy in treating childhood 25OHD deficiency. Methods: Children aged 2–16 years with 25OHD <50 nmol/L were randomised to either standard (5000 IU daily for 80 days) or stoss (100 000 IU weekly for 4 weeks) cholecalciferol. Participants underwent an evaluation of effectiveness and safety. The 25OHD level, random spot calcium: creatinine ratio (Ca:Cr) and compliance were measured at 12 weeks. Results: A total of 151 children were enrolled in the study (68 standard and 83 stoss), median age 9 years (inter-quartile range (IQR): 6–12 years). Baseline 25OHD levels were 26 nmol/L (IQR: 19–35 nmol/L) and 32 nmol/L (IQR: 24–39 nmol/L) in the standard and stoss groups, respectively. At 12 weeks, the median 25OHD level was significantly greater in the standard versus stoss group (81 vs. 67 nmol/L; P = 0.005); however, >80% of participants in both groups achieved sufficiency (25OHD > 50 nmol/L) and had normal urinary Ca:Cr, with no significant difference seen between groups. Compliance was similar in the two groups. Conclusions: Compared to stoss, standard therapy achieved higher 25OHD levels at 12 weeks; however, in both groups, there was a similar proportion of participants who achieved 25OHD sufficiency, with no evidence of toxicity. Unlike other studies, simplifying the treatment regimen did not improve compliance. These results support stoss therapy as an effective and safe alternative therapy for the treatment of paediatric vitamin D deficiency.