Bone Mineral Density and Vitamin D Status Among African American Children With Forearm Fractures

Abstract

WHAT'S KNOWN ON THIS SUBJECT: Forearm fractures are unique injuries which are associated with lower bone mineral density in adults and white children. The relationships among bone mineral density, 25-hydroxyvitamin D status, and risk for forearm fracture have not been investigated in African American children. WHAT THIS STUDY ADDS:Our data support an association between both lower bone mineral density and vitamin D deficiency and increased odds of forearm fracture in African American children. Promotion of bone health is indicated in this population.abstract OBJECTIVE: To determine whether African American children with forearm fractures have decreased bone mineral density and an increased prevalence of vitamin D deficiency (serum 25-hydroxyvitamin D level #20 ng/mL) compared with fracture-free control patients. METHODS:This case-control study in African American children, aged 5 to 9 years, included case patients with forearm fracture and control patients without fracture. Evaluation included measurement of bone mineral density and serum 25-hydroxyvitamin D level. Univariable and multivariable analyses were used to test for associations between fracture status and 2 measures of bone health (bone mineral density and 25-hydroxyvitamin D level) while controlling for other potential confounders. RESULTS:The final sample included 76 case and 74 control patients. There were no significant differences between case and control patients in age, gender, parental education level, enrollment season, outdoor play time, height, or mean dietary calcium nutrient density. Cases were more likely than control patients to be overweight (49.3% vs 31.4%, P = .03). Compared with control patients, case patients had lower whole body z scores for bone mineral density (0.62 6 0.96 vs 0.98 6 1.09; adjusted odds ratio 0.38 [0.20-0.72]) and were more likely to be vitamin D deficient (47.1% vs 40.8%; adjusted odds ratio 3.46 [1.09-10.94]). CONCLUSIONS:These data support an association of lower bone mineral density and vitamin D deficiency with increased odds of forearm fracture among African American children. Because suboptimal childhood bone health also negatively impacts adult bone health, interventions to increase bone mineral density and correct vitamin D deficiency are indicated in this population to provide short-term and long-term benefits. Pediatrics 2012;130:e553-e560