Vitamin D and Fracture Risk in Early Childhood: A Case-Control Study

Vitamin D level and low-energy fracture risk in children and adolescents: a population-based case-control study of 45 cases

The objective of this study is to document the rate of vitamin D deficiency and insufficiency among children with low-energy fractures and compare it to fracture-free control group. We included all children under 15 years presenting to the emergency department with low-energy fractures; controls were children without history of fractures from the outpatient department. Conventional X-ray and laboratory blood tests were performed. Vitamin D deficiency was defined as serum level ≤20 ng/ml, and the mean values were compared through two-sample t -tests. The influence of vitamin D on the fractures was defined using Chi-square test, significance with P -value < 0.05. The relationships between variables and odds of fracture occurrence were examined using logistic regression models. The final sample included 37 cases (30 males, 7 females, 7.4 ± 3.7 years) and 70 control individuals (42 males, 28 females, 7.8 ± 4.6 years) without significant differences regarding age, sex, and month of inclusion. Children with fractures had lower levels of vitamin D (21.87 ± 8.40 ng/ml vs. 25.89 ± 7.62 ng/ml) ( P = 0.01). Vitamin D played a protective role against low-energy fractures (OR, 1.08; 95% CI, 1.01-1.14; P = 0.02), boys showed three times greater fracture risk than girls (OR, 3.00; 95% CI, 1.12-8.07; P = 0.03). Finally, vitamin D deficiency correlated with almost five times increased risk of pediatric low-energy fractures (OR, 4.63; 95% CI, 1.92-11.18; P = 0.001). This is the first MENA study establishing a relation between vitamin D deficiency and low-energy fractures among children and adolescents. The findings show the protective role of vitamin D on the pediatric bone and may help physicians preventing morbidity on children and costs on their families and the socioeconomic health system.

Value-Driven Pediatric Supracondylar Humerus Fracture Care: Implementing Evidence-Based Practices

Supracondylar humerus fractures are high-volume injuries in children; therefore, value-driven treatment has far-reaching implications for patients and families as well as healthcare systems. Children younger than 5 years can remodel posterior angulation. Most Type IIa fractures will maintain alignment after closed reduction. Many patients with surgical fractures can safely wait for nonemergent fixation. Outpatient surgery is associated with shorter surgical time, lower costs, and fewer return visits to the emergency department with no increase in adverse events. Type III fractures treated the following day do not have higher rates of open reduction, and patients with associated nerve injuries have no difference in recovery time compared with those treated more urgently. Pediatric-trained surgeons generally provide more efficient care (shorter surgical time and less after-hours surgery); however, their outcomes are equivalent to non-pediatric orthopaedic surgeons. Community hospitals have lower costs compared with teaching hospitals; therefore, transferring patients should be avoided when feasible. Postoperative care can be streamlined in uncomplicated cases to minimize radiographs, therapy referrals, and multiple visits. Splinting offers safer, lower cost immobilization over casting. With staffing shortages and an increasingly burdened healthcare system, it is imperative to maximize nonsurgical care, use outpatient facilities, and minimize postoperative requirements without negatively affecting patient outcomes.

Pediatric Fractures: Does Vitamin D Play a Role?

BACKGROUND

Vitamin D (25-OHD) deficiency and insufficiency are reported in about half of all children. The literature on low 25-OHD and pediatric fracture risk presents inconsistent results. This study evaluates the association between pediatric fractures and 25-OHD, parathyroid hormone (PTH), and calcium.

METHODS

This is a prospective case-control study in 2 urban pediatric emergency departments (2014-2017). Patients aged 1 to 17 requiring intravenous access were enrolled. Demographics, nutrition, and activity information were recorded and levels of 25-OHD, calcium, and PTH were measured.

RESULTS

Two hundred forty-five subjects were enrolled: 123 fractures and 122 controls. Overall, the mean 25-OHD level was 23 ng/mL±8.5: 52 (21%) of patients were 25-OHD sufficient; 193 (79%) were not. Ninety-six percent of patients with lower extremity fractures had low 25-OHD versus 77% of patients with upper extremity fractures (P=0.024). The fracture cohort was younger (P=0.002), included more males (P=0.020), and spent more time playing outdoor sports (P=0.011) than the control cohort. The 25-OHD level (fracture 22.8 ng/mL±7.6 vs. nonfracture 23.5 ng/mL±9.3, P=0.494) and median calcium level (fracture 9.8 mg/dL vs. nonfracture 10.0 mg/dL, P=0.054) were similar between cohorts. The median PTH level was higher in the fracture than the control cohort (33 vs. 24.5 pg/mL; P<0.0005); PTH was elevated to hyperparathyroidism (>65 pg/mL) in 13% of fractures and 2% of controls (P=0.006). Matched subgroup analysis of 81 fracture patients and 81 controls by age, gender, and race showed that PTH was the only variable independently associated with increased odds of fracture (odds ratio=1.10, 95% CI, 1.01-1.19, P=0.021) in a model adjusted for vitamin D sufficiency and time spent playing outdoor sports.

CONCLUSIONS

Low 25-OHD is common in children with fractures but we found no difference in 25-OHD levels between fracture and nonfracture cohorts. This research can impact evidence-based guidelines on vitamin D level screening and/or supplementation after fracture.

LEVEL OF EVIDENCE

Diagnostic level IV-case-control study.

Relationship Between Hypovitaminosis D and Fractures Among Adolescents With Overweight or Obesity

Adolescents with overweight/obesity are at risk for vitamin D insufficiency and deficiency. Both overweight/obesity and vitamin D insufficiency/deficiency may predispose to fractures. We enrolled 103 participants (53.3% females, 15.9 ± 2.2 years) in a retrospective case-control study to determine whether an association exists between fractures and a low 25-hydroxyvitamin D (25[OH]D) among adolescents whose body mass index (BMI) ≥ 85 percentile. Cases (n = 28) sustaining a low/medium impact fracture were matched to controls (n = 75) without a fracture history. A conditional-logistic regression analysis addressing the common vitamin D insufficiency/deficiency cutoffs was used. Overweight, obesity, and significant obesity rates were 10.7%, 53.4%, and 35.9%, respectively. Mean (±SD) 25(OH)D was 16.5 ± 6.4 ng/mL. In all, 25(OH)D insufficiency rates (level <20 ng/mL) were 70.5%. Matched cases and controls had similar 25(OH)D insufficiency/deficiency rates (P > .05). Controlling for race and seasonality showed no association between fractures and 25(OH)D insufficiency/deficiency (P > .05). These data suggest that fractures are not associated with low 25(OH)D levels among adolescents whose BMI ≥ 85th percentile.

Prevalence of inadequate vitamin D level and its predictors in children presenting with torus fractures

BACKGROUND

Review of the published articles does not show any study done to see if children with torus fracture are with Vitamin D deficiency. The aim of this study was to determine association of inadequacy of Vitamin D level with torus fracture and its predictors in children in Karachi Pakistan.

METHODS

Patient underage of 13 years came with torus fracture were included in study, and managed non-operatively with below elbow cast. Proforma was made which includes demographic data (age, gender, nutritional status) and exposure to sunlight, dietary habits, kind to apparel and type of accommodation they were living at. All participants underwent measurement of serum vitamin D level.

RESULTS

Out of 558 children presented with limb fractures in emergency department, 190 (34.05%) had torus fracture, with mean age of 6.0 ± 4.2 years. 93 (48.94%) in pre-school group, 59 (31.05%) in school and 38 (20%) were breast-fed. On nutritional status, malnourished were 72 (37.89%), out of which 32 (44.44%) had first-degree malnutrition. On vitamin D level status only 52 (27.36%) participants had Vitamin D within normal range while 86 (45.26%) were found Vitamin D deficient. We found that vitamin D level is directly related to nutritional status, duration of sun exposure maternal vitamin d levels and not significantly related to age, gender, type of accommodation and different fabric types.

CONCLUSION

In this study torus fracture in children is significantly associated with Vitamin D deficiency, with common predictors including nutritional status, maternal Vitamin D level for lactating mothers and duration of exposure of sunlight. Vitamin D supplementation in children can prevent a significant number of fractures via national programs for food fortification and increase the awareness of general population on the importance of sunlight exposure and intake of food rich in Vitamin D.

Different Vitamin D Supplementation Strategies in the First Years of Life: A Systematic Review

Vitamin D (VD) is an essential micronutrient with multiple functions for human growth, and adequate intake should be guaranteed throughout life. However, VD insufficiency is observed in infants all over the world. Low VD concentration in the breast milk of non-supplemented mothers and low compliance to VD daily supplementation are the main causes of VD insufficiency, especially in the long term. Furthermore, VD supplementation dosages are still debated and differ by country. We conducted a systematic review to compare the most recent evidence on different postnatal VD supplementation strategies, determining whether supplementation given to the mother is as effective as that administered directly to the child, and whether different dosages and administration schedules differ significantly in terms of efficacy and safety. We identified 18 randomized controlled trials (RCTs) addressing the role of infant (n = 961), maternal (n = 652) or combined infant and maternal VD supplementation (n = 260 pairs). In all studies, similar outcomes emerged in terms of efficacy and safety. According to our findings, alternative approaches of VD supplementation may be adopted, especially in cases where the adherence to daily supplementation strategies is poor. This review shows that different dosages and supplementation strategies result in similar VD sufficiency rates. Therefore, international guidelines may be revised in the future to offer multiple and different options of supplementation for specific settings and ages.

Vitamin D and Forearm Fractures in Children Preliminary Findings: Risk Factors and Correlation between Low-Energy and High-Energy Fractures

Background: The forearm is the most common fracture site in childhood, accounting for every fourth pediatric fracture. It is well described that vitamin D is involved in the regulation of bone mineralization and skeletal homeostasis by the regulation of calcium absorption. The aim of our study was to determine the influence of 25-hydroxyvitamin D levels on forearm fracture falls in a pediatric population, depending on level of energy impact. Additionally, we also aimed to evaluate the correlation between 25-hydroxyvitamin D levels and other tested risk factors for pediatric fractures. Methods: We evaluated 50 eligible children aged 3 to 12 years with a forearm fracture. According to energy impact, patients were grouped into low-energy fractures (LEF) and high-energy fractures (HEF) groups. The general characteristics of the patients included age, gender, sport participation, and fractured bone and its localization. We analyzed 25-hydroxyvitamin D, parathyroid hormone (PTH), calcium, magnesium, phosphate, C-reactive protein (CRP) levels, and body mass index (BMI). Results: There is a significant difference in the 25-hydroxyvitamin D levels distribution between LEF and HEF (p < 0.001) and PTH levels (p = 0.002). For magnesium levels, calcium levels, phosphate levels, and CRP levels, there were no significant differences in their frequency distribution. For the group of patients with LEF, there is a significantly positive correlation between 25-hydroxyvitamin D and calcium levels (p = 0.019) and a borderline significantly positive correlation between 25-hydroxyvitamin D and magnesium levels (p = 0.050). For the group of patients with HEF, there was only a significantly positive correlation between 25-hydroxyvitamin D and PTH levels (p < 0.001). Conclusions: Children with LEF were more frequently insufficient in 25-hydroxyvitamin D levels but had normal calcium levels, compared to the ones with HEF. These findings suggest that LEF and HEF in children might to a certain degree have different pathophysiological mechanisms.

Vitamin D level and fractures in children and adolescents: a systematic review and meta-analysis

INTRODUCTION

The aim of the study was to determine the relationship between vitamin D levels and the risk of bone fractures in children and adolescents.

MATERIALS AND METHODS

PubMed, Embase, and Cochrane library databases were searched using subject and free words. The Newcastle-Ottawa scale form was used to assess literature quality. ReVman 5.2 and Stata 13.0 were used for statistical analyses. The results were expressed as the mean difference (MD)/odds ratio (OR) and 95% confidence interval (95% CI). The heterogeneity test was conducted according to I² and Q tests. Egger's test was used to evaluate publication bias.

RESULTS

Thirteen studies (3943 participants ≤ 18 years old) were included, and the quality of the literature was acceptable. Regarding the 25-hydroxyvitamin D (25OHD) level in the random effects model, the MD = - 0.12 ng/mL (95% CI: -1.93, 1.69), I² = 83%, and P < 0.00001, indicating large heterogeneity. Subgroup analyses were conducted according to vitamin D supplementation and 25OHD level, the sources of heterogeneity were not found. Regarding the proportion of subjects with vitamin D deficiency in the random effects model, OR = 1.09 (95% CI: 0.67, 1.79), I² = 79%, and P < 0.0001. By sensitivity analysis, after removing Al-Daghri's study, OR = 1.22 (95% CI: 0.96, 1.56), I² = 0%, and P = 0.64.

CONCLUSION

There is no relationship between vitamin D level and the risk of bone fractures in children and adolescents.

Association of serum 25(OH)Vit-D levels with risk of pediatric fractures: a systematic review and meta-analysis

The association between the risk of fractures and suboptimal vitamin D (Vit-D) status remains controversial in children. This meta-analysis suggested that serum 25(OH)Vit-D levels were lower in pediatric cases with fractures. 25-hydroxyvitamin D (25(OH)Vit-D) levels less than 50 nmol/L were associated with increased fracture risk in children.

INTRODUCTION

This study aimed to assess the association between serum 25(OH)Vit-D and the risk of fractures in children, and to explore the sources of heterogeneity and investigate their impact on results.

METHODS

Systematic review and meta-analysis were conducted for observational studies comparing serum 25(OH)Vit-D levels between fracture and non-fracture pediatric cases. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS).

RESULTS

Analysis on 17 case-control and 6 cross-sectional studies (2929 fracture cases and 5000 controls) suggested that 25(OH)Vit-D was lower in fracture cases than in controls (pooled mean difference (MD) = - 3.51 nmol/L; 95% confidence interval (CI): - 5.60 to - 1.42) with a heterogeneity (I²) of 73.9%. The sensitivity analysis which merged the case-control studies that had a NOS score ≥ 4 showed a pooled MD of - 4.35 nmol/L (95% CI: - 6.64 to - 2.06) with a heterogeneity (I²) of 35.9%. Pooled odds ratio of fracture in subjects with 25(OH)Vit-D ≤ 50 nmol/L compared to subjects with 25(OH)Vit-D > 50 nmol/L was 1.29 (95% CI: 1.10 to 1.53; I² < 1%).

CONCLUSION

This study indicated that serum 25(OH)Vit-D levels were lower in pediatric patients with fractures. 25(OH)Vit-D ≤ 50 nmol/L was associated with increased fracture risk in children.

Prevalence of vitamin D deficiency in children presenting with supracondylar fractures of humerus

OBJECTIVE

The purpose of the current analysis is to evaluate the predominance of vitamin D inadequacy in children with supracondylar fracture of the humerus.

METHODS

This is a cross-sectional study conducted at Dr Ruth K. M. Pfau Civil, Hospital, Karachi, Pakistan, from December 2019 to July 2020. Patients aged 18 months-18 years presenting with supracondylar fractures were included in the study. Patients were divided into four groups based on their age as toddlers (18 months to 3 years), pre-school age (3-5 years), school-age (6 to 11 years) and adolescents (11-18 years).

RESULTS

A total of 227 children presented with upper limb fractures of which 72 (31.7%) were supracondylar. The mean vitamin D level was found to be 32.5 ± 9.1 ng/mL. Of the study subjects, low vitamin D levels were found in 34.7% (n = 25), adequate in 59.7% (n = 43) and ideal in 5.5% (n = 4) of patients. The mean vitamin D levels for toddlers were 33.5 ng/mL, for preschool children was 27.66 ng/mL, for school-age children was 30.4 ng/mL and for adolescents was 37 ng/mL.

CONCLUSION

Vitamin D deficiency is not only restricted to Pakistan but also other parts of the world, although the reasons may vary in each of those regions. However, vitamin D supplementation in all parts of the globe can prevent a significant number of fractures. This prevalence study showed vitamin D deficiency in 35% of children with supracondylar fractures, with the lowest mean values in the preschool age group.

Vitamin D levels in Irish children with fractures: A prospective case-control study with 5 year follow-up

INTRODUCTION

Twenty-five-hydroxy-vitamin D3 (25-OH-vit D) is a prohormone that is essential for normal calcium homeostasis and bone metabolism. Understanding its role is an important component of the proper care of the pediatric orthopaedic patient. The aim of this study was to determine whether children in Ireland with fractures have increased prevalence of 25-OH-Vit D deficiency compared with age matched controls and to ascertain the relationship between a low 25-OH-vit D level and the incidence of fractures in Irish children. We hypothesised that children presenting to our centre following a fracture would have significantly lower 25-OH-vit D.

METHODS

A prospective case-control study at a large urban tertiary referral academic hospital located in Dublin, Ireland was completed over a 14 month period from June 2014 to August 2015. A total of 116 subjects, distributed as cases (n = 58) and controls (n = 58) were included in this study. Whole blood (10 ml) was taken in two serum bottles from each patient. Serum 25-hydroxy-vitamin D3 levels were measured. An age matched control group was generated from other children attending the hospital, who also had vitamin D levels measured for different clinical reasons. We followed up both the fracture and control group for the next 5 years to assess the repeat fracture rate.

RESULTS

Fifty-eight patients with a fracture requiring operative intervention, were included in the study. Statistical analysis was performed comparing to 58 age and sex-matched controls. The mean vitamin D level for the fracture group was 63.2 nmol/L (SD = 27.3), which was higher than the mean of the controls (62.5 nmol/L) (SD = 21.3) (p = 0.86), but this difference was found not to be statistically significant in unadjusted analysis. There was no statistically significant difference in the number of patients classified with low serum Vitamin D levels (<50 nmolL), with the fracture group consisting of 22 (37.9%) patients, and the control group of 17 patients (29.3%) (p = 0.33) with a level below 50 nmol/L. At five-year follow-up, 11 of the 58 patients (18.9%) in the fracture group went on to have a further fracture compared with eight patients (13.7%) from the control group. Out of these 11 from the fracture group five (45.45%) had been found to have a low serum 25-OH-Vit D level five years previously. Out of the eight controls that presented with a fracture within the five-year period, 3 (37.5%) had had a low vitamin D level at the origin of this study.

CONCLUSION

The results of this study show that children presenting to our institution with low energy fractures have a prevalence of 38% 25-hydroxy-vitamin D deficiency. This study included children from age 1 to 16 primarily Caucasian encompassing all fracture types resulting from accidental trauma. Our findings suggest that in an Irish pediatric population vitamin D status may impact fracture risk with more than one-third being deficient in this review.

Association between maternal smoking during pregnancy and risk of bone fractures in offspring: a systematic review and meta-analysis

This study aimed to investigate the effect of maternal smoking during pregnancy (MSDP) on the risk of bone fractures in the offspring through a systematic review and meta-analysis. The PubMed, Web of Science, and Scopus databases were systematically searched for relevant articles published through July 2019. According to heterogeneity, the pooled risk ratio (RR) and odds ratio (OR) and their corresponding 95% confidence interval (CI) were obtained using fixed or random effects models. The heterogeneity and quality of the included studies were assessed by the I-squared (I2 ) statistic and the Newcastle-Ottawa scale, respectively. Sensitivity analyses were performed to test the effect of MSDP misclassification on the results. The review of 842 search records yielded 5 studies including 8,746 mother-child pairs that were included in the meta-analysis. Pooling adjusted effect measures showed that MSDP was not associated with a later risk of bone fractures in the offspring (pooled RR, 1.15; 95% CI, 0.84-1.58; I2 =66.8%; P=0.049). After the adjustment for misclassification, MSDP may be associated with a 27% increased risk of bone fracture (pooled OR, 1.27; 95% CI, 1.00-1.62; I2 =0%; P=0.537). After the adjustment for misclassification, MSDP is associated with an increased risk of bone fractures among children whose mothers smoked during pregnancy.

Vitamin D in Toddlers, Preschool Children, and Adolescents

BACKGROUND

Vitamin D supplementation is known to both prevent and treat rickets, a disease of hypomineralized bone. Childhood is a period of great bone development and, therefore, attention to the vitamin D needed to optimize bone health in childhood is imperative.

SUMMARY

Observational studies have pointed to a vitamin D status, as indicated by a 25-hydroxyvitamin D concentration, of 50 nmol/L to ensure avoidance of rickets and of 75 nmol/L to optimize health. However, the benefits of achieving these levels of vitamin D status are less evident when pediatric randomized, controlled trials are performed. In fact, no specific pediatric vitamin D supplementation has been established by the existing evidence. Yet, study of vitamin D physiology continues to uncover further potential benefits to vitamin D sufficiency. This disconnection between vitamin D function and trials of supplementation has led to new paths of investigation, including establishment of the best method to measure vitamin D status, examination of genetic variation in vitamin D metabolism, and consideration that vitamin D status is a marker of another variable, such as physical activity, and its association with bone health. Nevertheless, vitamin D supplementation in the range of 10-50 μg/day appears to be safe for children and remains a promising intervention that may yet be supported by clinical trials as a method to optimize pediatric health. Key Message: Pediatric vitamin D status is associated with avoidance of rickets. Randomized, controlled trials of vitamin D supplementation for pediatric bone health are limited and equivocal in their results. Beyond bone, decreased risk for autoimmune, infectious, and allergic diseases has been associated with higher vitamin D status. The specific vitamin D supplementation to optimize toddler, child, and adolescent outcomes is unknown, but doses 10-50 μg/day are safe and may be beneficial.

Preschool Obesity Is Associated With an Increased Risk of Childhood Fracture: A Longitudinal Cohort Study of 466,997 Children and Up to 11 Years of Follow-up in Catalonia, Spain

This study aimed to determine if having an overweight or obese range body mass index (BMI) at time of beginning school is associated with increased fracture incidence in childhood. A dynamic cohort was created from children presenting for routine preschool primary care screening, collected in the Information System for Research in Primary Care (SIDIAP) platform in Catalonia, Spain. Data were collected from 296 primary care centers representing 74% of the regional pediatric population. A total of 466,997 children (48.6% female) with a validated weight and height measurement within routine health care screening at age 4 years (±6 months) between 2006 and 2013 were included, and followed up to the age of 15, migration out of region, death, or until December 31, 2016. BMI was calculated at age 4 years and classified using WHO growth tables, and fractures were identified using previously validated ICD10 codes in electronic primary care records, divided by anatomical location. Actuarial lifetables were used to calculate cumulative incidence. Cox regression was used to investigate the association of BMI category and fracture risk with adjustment for socioeconomic status, age, sex, and nationality. Median follow-up was 4.90 years (interquartile range [IQR] 2.50 to 7.61). Cumulative incidence of any fracture during childhood was 9.20% (95% confidence interval [CI] 3.79% to 14.61%) for underweight, 10.06% (9.82% to 10.29%) for normal weight, 11.28% (10.22% to 12.35%) for overweight children, and 13.05% (10.69% to 15.41%) for children with obesity. Compared with children of normal range weight, having an overweight and obese range BMI was associated with an excess risk of lower limb fracture (adjusted hazard ratio [HR] = 1.42 [1.26 to 1.59]; 1.74 [1.46 to 2.06], respectively) and upper limb fracture (adjusted HR = 1.10 [1.03 to 1.17]; 1.19 [1.07 to 1.31]). Overall, preschool children with an overweight or obese range BMI had increased incidence of upper and lower limb fractures in childhood compared with contemporaries of normal weight. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

Genetic predisposition for vitamin D deficiency is not associated with adverse outcome of very low birth weight infants: A cohort study from the German Neonatal Network

Objective

Postnatal vitamin D supplementation is standard of care in neonates and preterm infants. Despite routine supplementation of vitamin D, a wide range of complications related to vitamin D deficiency has been described in the literature. Since standard vitamin D supplementation might be not sufficient in preterm infants with a genetic predisposition for vitamin D deficiency, we investigated the outcome of preterm infants with regard to their genetic estimated vitamin D levels.

Methods

Preterm infants with a birth weight below 1500 grams were included in the German Neonatal Network at the time of their birth and tested at the age of five. The vitamin D level was genetically calculated based on three single nucleotide polymorphisms (SNPs: rs12794714, rs7944926 and rs2282679) which alter vitamin D synthesis pathways. Specific alleles of these polymorphisms are validated markers for low plasma vitamin D levels. Outcome data were based on baseline data at the time of birth, typical complications of prematurity, body measurements at the age of five and occurrence of bone fractures. T-test and Fisher’s exact test were used for statistical comparison.

Results

According to their genetic predisposition, 1,924 preterm infants were divided into groups of low (gsVitD < 20. Percentile), intermediate and high vitamin D level estimates. Low genetic vitamin D level estimates could not be shown to be associated with any adverse outcome measures examined. The analyses covered data on aforementioned determinants.

Conclusion

Low genetic vitamin D level estimates could not be shown to be associated with previously described adverse outcome in preterm infants.

Consumption of Cow's Milk in Early Childhood and Fracture Risk: A Prospective Cohort Study

Cow's milk is consumed by most North American children, yet the relationships between the volume and fat content of cow's milk consumed and childhood fracture risk are unclear. Our primary objectives in this study were to evaluate whether the volume or fat content of cow's milk consumed at 1-3 years of age was associated with the risk of fracture between 3 and 10 years of age. This was a prospective cohort study of 2,466 children enrolled in Toronto, Ontario, Canada, between 2008 and 2016. The primary exposure was volume of cow's milk consumed between the ages of 1 and 3 years, and the secondary exposure was average percentage of milk fat consumed by each child during the same period. The primary outcome was a parental report of child fracture at ages 3-10 years. In the primary and secondary adjusted analyses, no association between milk volume and fracture risk (adjusted relative risk = 1.04, 95% confidence interval: 0.87, 1.26) or between milk-fat content and fracture risk (adjusted relative risk = 1.05, 95% confidence interval: 0.84, 1.31) was observed. In this study, we did not identify a protective association of early childhood cow's milk volume or fat consumption with fracture risk in later childhood. Future prospective research is needed to understand whether cow's milk is beneficial for fracture prevention through the life course.

Vitamin D Trends in the Pediatric Orthopaedic Population: A Survey

BACKGROUND

Within the last decade, multiple studies have demonstrated the potential health benefits of vitamin D supplementation including improved bone health, reduced fracture risk, protection from autoimmune disease, and decreased cancer risk. Because of the prevalence of vitamin D deficiency in pediatric populations and despite recent evidence of increased vitamin D supplementation in the United States, our goal is to assess the knowledge of current vitamin D recommendations among pediatric orthopaedists and fellows within the Pediatric Society of North America (POSNA). It is our purpose to use the data to increase awareness and understanding of vitamin D among all pediatric providers.

METHODS

Our survey was distributed to 1316 POSNA members via a series of 2 email requests to participate in the survey on the SurveyMonkey website. They agreed to participate by responding positively on the first page of the survey. The data was depersonalized and analyzed via χ and the Fisher exact testing.

RESULTS

A total of 395 responses were recorded. Overall, 69% of participants rated their vitamin D knowledge as fair to good. In total, 68% of participants have been in practice over 10 years and represented most US geographic regions fairly equally. Most estimate that over 25% of their practice is vitamin D deficient with about a 50% compliance rate of supplementation. Over 30% of participants feel vitamin D management is mostly the role of the pediatrician; however, 64% of participants discuss or check vitamin D levels in their practice for patients with repeat fractures, medical comorbidities, or nonunions most commonly.

CONCLUSIONS

Survey participants demonstrated a wide variety of responses indicating their understanding of vitamin D testing and supplementation. Although providers estimate a high deficiency rate, many do not routinely check vitamin D. When they do check, there is no standard indication for testing or supplementation and many believe this to be the role of the pediatrician or endocrinologist. More studies are needed to provide a standardized protocol for vitamin D testing and supplementation in the pediatric orthopaedic literature.

CLINICAL RELEVANCE

POSNA survey.

Vitamin D, and Maternal and Child Health

Vitamin D has important roles in calcium metabolism and in the prevention of rickets and osteomalacia; low levels of 25-hydroxyvitamin D are common in the general population and amongst pregnant women. Whilst there is a wealth of observational evidence linking vitamin D deficiency to a wide range of disease outcomes, there are currently few high-quality randomised controlled trials to confirm any causal associations, although many are currently in progress. Furthermore, currently, the vast majority of published guidelines recommend standard supplemental vitamin D doses for children and pregnant women, yet there is increasing recognition that individual characteristics and genetic factors may influence the response to supplementation. As such, future research needs to concentrate on documenting definite beneficial clinical outcomes of vitamin D supplementation, and establishing personalised dosing schedules and demonstrating effective approaches to optimising initiation and adherence.

Vitamin D intake, calcium intake and physical activity among children with wrist and ankle injuries and the association with fracture risk

BACKGROUND

Several studies have revealed a substantial increase in the incidence of fractures in children in the past few decades.

AIM

To assess the strength of the association between suggested risk factors and fracture prevalence in children.

METHOD

A cross sectional observational study. Children aged 6-15 years and their guardians presenting to the Emergency Department of a single tertiary paediatric hospital were recruited. Self-reported data on vitamin D intake, calcium intake and physical activity were collected. All participants had a radiograph of their injured limb reported by a consultant radiologist, on the basis of which they were classified into fracture or no fracture groups. Statistical analysis included descriptive statistics and binary logistic regression.

RESULTS

Of the 130 patients recruited, 53 (41%) had sustained a fracture. The overwhelming majority of children (98%) did not consume the recommended daily dietary amount of vitamin D (400 IU/day). Low calcium intake and low levels of physical activity were also ascertained. However, there were no significant differences between fracture and no fracture groups for vitamin D intake, calcium intake or physical activity. Both site of injury (wrist) and sex (male) were associated with increased fracture risk ( p = 0.001 and p = 0.05, respectively). Logistic regression showed a statistically significant relationship between calcium intake and fracture risk (every additional unit of calcium consumption (mg/day) decreased the likelihood of fracture by 0.002, 95% confidence interval, 0.001-0.003).

CONCLUSIONS

Low dietary intake of calcium and vitamin D and low levels of physical activity were evident. Fracture risk was significantly associated with reduced calcium intake but showed no association with vitamin D intake or physical activity.

The Role of Vitamin D in Pediatric Orthopedics

Understanding the role of vitamin D is an important component of the proper care of the pediatric orthopedic patient. Vitamin D is an essential component of bone metabolism in the growth and development of the pediatric skeleton, which can be acutely affected by changes to the body's vitamin D, calcium, and phosphate levels, resulting in pathologic conditions such as rickets or fractures. This article reviews the main areas in which vitamin D relates to pediatric orthopedics and highlights some of the areas where future research is being directed.

Study designs: Part 3 - Analytical observational studies

In analytical observational studies, researchers try to establish an association between exposure(s) and outcome(s). Depending on the direction of enquiry, these studies can be directed forwards (cohort studies) or backwards (case-control studies). In this article, we examine the key features of these two types of studies.