Do Adolescent Idiopathic Scoliosis Patients With Vitamin D Deficiency Have Worse Spine Fusion Outcomes?

BACKGROUND: Prior research has shown that patients with adolescent idiopathic scoliosis (AIS) have a higher prevalence of vitamin D deficiency compared with healthy peers. In adult orthopaedic populations, vitamin D deficiency has been shown to be a risk factor for higher reported pain and lower function. We investigated whether there was an association between vitamin D levels and AIS patient-reported outcomes, as measured by the Scoliosis Research Society (SRS-30) questionnaire. METHODS: This was a single-center, cross-sectional study. Postoperative AIS patients were prospectively recruited during routine follow-up visits, 2 to 10 years after spine fusion. Vitamin D levels were measured by serum 25-hydroxyvitamin D (ng/mL). Patients were categorized based on vitamin D level: deficient (<20 ng/mL), insufficient (20 to 29 ng/mL), or sufficient (≥30 ng/mL). The correlation between vitamin D levels and SRS-30 scores was analyzed using multivariable analysis and pair-wise comparisons using Tukey method. RESULTS: Eighty-seven AIS patients (83% female) were enrolled who presented at median 3 years (interquartile range: 2 to 5 y; range: 2 to 10 y) after spine fusion. Age at time of surgery was mean 15 (SD±2) years. Major coronal curves were a mean of 57 (SD±8) degrees preoperatively and 18 (SD±7) degrees postoperatively. It was found that 30 (34%) of patients were vitamin D sufficient, 33 (38%) were insufficient, and 24 (28%) were deficient. Although there was no correlation between vitamin D level and Pain, Mental Health, or Satisfaction domains ( P >0.05), vitamin D-deficient patients were found to be younger ( P <0.001) and had lower SRS-30 function ( P =0.002), Self-image ( P <0.001), and total scores ( P =0.003). CONCLUSIONS: AIS patients with vitamin D deficiency (<20 ng/mL) are more likely to be younger age at time of surgery, and report lower Function, Self-image, and Total SRS-30 scores postoperatively. Further work is needed to determine whether vitamin D supplementation alters curve progression and patient outcomes. LEVEL OF EVIDENCE: Level II-prognostic study.

A randomized clinical trial of vitamin D supplementation in healthy adolescents.

PURPOSE: The most safe and effective dose of vitamin D supplementation for healthy adolescents is currently unknown. The aim of this study was to compare the efficacy of 200 IU versus 1,000 IU of daily vitamin D3 for supplementation in healthy adolescents with baseline vitamin D sufficiency. METHODS: We conducted a double-blind, randomized clinical trial. Fifty-six subjects, ages 11-19 years, with baseline vitamin D sufficiency received 1,000 IU or 200 IU of daily vitamin D3 for 11 weeks. Compliance was assessed using MEMS6 Trackcaps and pill counts. RESULTS: Fifty-three subjects completed the clinical trial. Subjects in the two treatment arms were similar in terms of age, race, gender, body mass index, and dietary calcium and vitamin D intake. Serum 25(OH)D level in the 200 IU treatment arm was 28.1 ± 6.2 ng/mL at baseline (mean ± SD) and 28.9 ± 7.0 ng/mL at follow-up. In the 1,000 IU treatment arm, 25(OH)D levels were 29.0 ± 7.3 and 30.1 ± 6.6 at baseline and follow-up, respectively. Mean change in 25(OH)D level did not differ significantly between treatment arms (p = .87), nor did mean change in parathyroid hormone, calcium, phosphate, bone turnover markers, fasting glucose, or fasting insulin. CONCLUSIONS: In healthy adolescents with baseline vitamin D sufficiency, supplementation with vitamin D3 doses of 200 and 1,000 IU for 11 weeks did not increase serum 25(OH)D levels, with no significant difference observed between treatment arms.

Bone mineral density, fracture, and vitamin D in adolescents and young women using depot medroxyprogesterone acetate.

STUDY OBJECTIVE: To evaluate bone mineral density (BMD) in adolescents and young adults treated with depot medroxyprogesterone acetate (DMPA). DESIGN, SETTING, PARTICIPANTS: Eighty-three healthy subjects, 13-20 years old, who received at least 3 DMPA injections in an urban adolescent clinic and underwent dual energy x-ray absorptiometry (DXA) were evaluated by chart review. MAIN OUTCOME MEASURES: Anthropometric data, DMPA use, BMD of the spine and hip, fracture history, and vitamin D status were collected. RESULTS: Subjects were a median age of 16.4 years old (range 13-20 years) when DMPA was initiated. The median number of DMPA injections was 5 (range 3-18) before the first DXA. At the spine and hip, respectively, BMD was normal (Z-score > -1.0 SD) for most subjects (79%, 86%). Subjects who received > 5 injections were more likely to have low spinal BMD (Z-score ≤ -2.0 SD) at first DXA (P = .018). In 15 subjects with repeat DXA measurements, after an additional median 6 injections, spinal BMD Z-score decreased by -0.33 ± 0.10 (mean ± SD, P = .004), as did absolute BMD at the hip (-0.019 ± 0.007 g/cm(2), P = .014). History of fracture was not associated with initial or subsequent BMD measurements. Most (12/13, 92.3%) subjects with vitamin D measurements were deficient (25-hydroxy vitamin D < 20 ng/mL). CONCLUSIONS: Most subjects on DMPA had normal BMD at first DXA. Low spinal BMD was associated with longer DMPA use, and some BMD measurements declined with prolonged use. Fracture history is not an absolute contraindication to DMPA use in this population. Studies are needed to determine possible benefits of vitamin D supplementation in DMPA users.