To reduce the risk of severe fracture, all children should be monitored for vitamin D status, argue the authors of a paper presented at the 2014 annual meeting of the Pediatric Orthopaedic Society of North America.
“Lower vitamin D levels are associated with surgical treatment of fractures,” explained Barbara Minkowitz, MD, “and therefore potentially permanent disability.” Dr. Minkowitz, who is in private practice with the Children’s Orthopaedic & Sports Medicine Center, in Morristown, N.J., presented data from her paper, “Association of Pediatric Fractures with Serum Vitamin D Levels Compared to Non-fracture Community Controls.”
“We looked at 1,133 healthy patients younger than 21 years of age,” said Dr. Minkowitz. “The 379 fracture patients were drawn from one pediatric orthopaedic group, and 754 control patients were drawn from 13 community pediatric groups. We collected demographic information, serum bone health assessment, and fracture history.”
Dr. Minkowitz stated that 82 percent of the study participants were “light-skinned,” with most of the rest being “dark-skinned,” including Hispanic and African Americans.
Serum level variations
According to Dr. Minkowitz, the mean vitamin D serum level for the entire patient population was 27.7 ng/mL. Within that population, the researchers found a wide range of vitamin D levels, with almost half the children in the 20s (Table 1).
“A population analysis showed that the lowest vitamin D levels were found in African-American participants, with a mean vitamin D level of 20.7 ng/mL,” she said. (According to the Institutes of Medicine, serum vitamin D levels greater than 20 ng/mL are generally considered adequate for bone and overall health in healthy individuals.)
“Hispanic participants averaged 23.1 ng/mL, and dark skin-toned children overall had an average vitamin D level of 22.2 ng/mL. This finding is consistent with the literature regarding lower vitamin D levels in this population. It is important to note that many of the light skin-toned children also had very low levels of vitamin D, which has not been noted nor stressed in the literature.”
Dr. Minkowitz noted that vitamin D levels in patients younger than 5 years could be stratified by diet: those identified by their parents as “poor eaters” averaged vitamin D levels of 23.1 ng/mL, while those described as “healthy eaters” averaged 30.7 ng/mL.
In addition, Dr. Minkowitz and her colleagues broke down serum level demographics in both the fracture and control cohorts and found them to be comparable.
“However, when we calculated the odds ratios [OR] for surgical fracture by vitamin D levels, we found that patients who had vitamin D levels of less than 12 ng/mL had an OR of 5.3 (compared to controls) of sustaining a fracture that needed to be treated surgically,” said Dr. Minkowitz. “Those in the 12- to 19-ng/mL group had an OR of 3.8; and those in the 20- to 29-ng/mL group had an OR of 2.7. We found no statistical difference for participants with vitamin D serum levels greater than 30 ng/mL.” This shows that 30-ng/mL serum vitamin D is a significant fragility fracture threshold linking fracture severity to vitamin D status.
Dr. Minkowitz explained that the study found no significant correlation between vitamin D levels and gender, age (except for patients younger than 5 years), sunscreen use, outdoor play, fracture history, season, and body mass index. Neither were parameters such as multivitamin use, mechanism of injury, and eating habits correlated to fracture severity.
“In summary, patients in both the control and fracture groups had comparable vitamin D levels overall,” she said, “although the likelihood of surgical fracture increased when vitamin D was less than 30 ng/mL.
“At-risk groups included those younger than 5 years of age described as poor eaters; Hispanics, African Americans, and other people of color; and surgical fracture patients. Based on our findings, we recommend that all children in high risk groups be routinely screened for vitamin D status,” she concluded.
Dr. Minkowitz’s coauthors include Barbara Cerame; Eileen Blechman Poletick, RN, DNP; Sherri Luxenburg; Nicole D. Formoso; Renee Eng; Samantha Nicole Easton; Jonathan Chevinsky; Scott Musial; Lior Fusman; Connor Jordan; and Ben H. Lee, MD, MPH, MSc.
Disclosure information: None of the authors report any conflicts.
Peter Pollack is the electronic content specialist for AAOS Now. He can be reached at email@example.com
- In this study comparing pediatric fracture patients with healthy community controls, researchers found similar vitamin D serum level demographics for both cohorts.
- Lower vitamin D serum levels were associated with an increased likelihood of surgical fractures, which could potentially cause permanent disability.
- Non-white children were at greater risk of low vitamin D serum levels.
- The authors recommend that all children be screened for vitamin D serum levels and supplemented with vitamin D and calcium.