Low Vitamin D Levels are Associated With Need for Surgical Correction of Pediatric Fractures

Background: There is growing concern over the relationship between the severity of pediatric fractures and low vitamin D [25-hydroxyvitaminD (25(OH) D)] status. Objective: Compare 25(OH) D levels and lifestyle of children with fractures to nonfracture controls to determine if 25(OH) D levels are associated with fractures and if there is a 25(OH) D fragility fracture threshold. Methods: Pediatric fracture and nonfracture controls were included. Bone health survey and medical record data were analyzed. Fractures were categorized using the Abbreviated Injury Scale (AIS). AIS 3 fractures were identified as fractures that required surgical intervention. Univariate and multivariable ordinal regression analyses were performed to identify potential risk factors for increased fracture severity. Results: A total of 369 fracture patients and 662 nonfracture controls aged 18 years and younger were included. Both groups' 25(OH) D levels were comparable. 25(OH) D was 27.5 +/- 8.9 in the fracture group compared with 27.4 +/- 9.1 ng/mL in nonfracture controls (P=0.914). AIS 3 fractures had lower 25(OH) D levels (24.6 +/- 9.3 ng/mL) versus AIS 1 and 2 (30.0 +/- 10.8 and 28.3 +/- 8.4, respectively, P=0.001). Univariate correlations for AIS severity were found with age (P=0.015) and outdoor playtime (P=0.042). Adjusted odds ratios for 25(OH) D levels < 12 ng/mL was 55.4 (P=0.037), 25(OH) D between 12 and 20 ng/mL was 6.7 (P=0.039), 25(OH) D between 20 and 30 ng/mL was 2.8 (P=0.208), and 25(OH) D between 30 and 40 was 1.7 (P=0.518). Clinical Relevance: Occurrence of a pediatric fracture was not associated with 25(OH) D levels in our study. However, children with lower vitamin D levels were found to be at higher risk for more severe fractures. Early evidence suggests that the target serum level for 25(OH) D should be at least 40 ng/mL in patients less than 18 years of age as the relative risk of more severe fractures increased as 25(OH) D levels decreased < 40ng/mL. Level of Evidence: Level III.