Anthropometry, Nutritional Status, and Dietary Intake in Pediatric Patients with Osteogenesis Imperfecta

Imaging in osteogenesis imperfecta: Where we are and where we are going

Osteogenesis imperfecta (OI) is a rare phenotypically and genetically heterogeneous group of inherited skeletal dysplasias. The hallmark features of OI include bone fragility and susceptibility to fractures, bone deformity, and diminished growth, along with a plethora of associated secondary features (both skeletal and extraskeletal). The diagnosis of OI is currently made on clinical grounds and may be confirmed by genetic testing. However, imaging remains pivotal in the evaluation of this disease. The aim of this article is to review the current role played by the various radiologic techniques in the diagnosis and monitoring of OI in the postnatal setting as well as to discuss recent advances and future perspectives in OI imaging. Conventional Radiography and Dual-energy X-ray Absorptiometry (DXA) are currently the two most used imaging modalities in OI. The cardinal radiographic features of OI include generalized osteopenia/osteoporosis, bone deformities, and fractures. DXA is currently the most available technique to assess Bone Mineral Density (BMD), specifically areal BMD (aBMD). However, DXA has important limitations and cannot fully characterize bone fragility in OI based on aBMD. Novel DXA-derived parameters, such as Trabecular Bone Score (TBS), may provide further insight into skeletal changes induced by OI, but evidence is still limited. Techniques like Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) can be useful as problem-solvers or in specific settings, including the evaluation of cranio-cervical abnormalities. Recent evidence supports the use of High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT) as a promising tool to improve the characterization of bone fragility in OI. However, HR-pQCT remains a primarily research technique at present. Quantitative Computed Tomography (QCT) is an alternative to DXA for the determination of BMD at central sites, with distinct advantages but considerably higher radiation exposure. Quantitative Ultrasound (QUS) is a portable, inexpensive, and radiation-free modality that may complement DXA evaluation, providing information on bone quality. However, evidence of usefulness of QUS in OI is poor. Radiofrequency Echographic Multi Spectrometry (REMS) is an emerging non-ionizing imaging method that holds promise for the diagnosis of low BMD and for the prediction of fracture risk, but so far only one published study has investigated its role in OI. To conclude, several different radiologic techniques have proven to be effective in the diagnosis and monitoring of OI, each with their own specificities and peculiarities. Clinicians should be aware of the strategic role of the various modalities in the different phases of the patient care process. In this scenario, the development of international guidelines including recommendations on the role of imaging in the diagnosis and monitoring of OI, accompanied by continuous active research in the field, could significantly improve the standardization of patient care.

Short-term effects of Mediterranean diet on nutritional status in adults affected by Osteogenesis Imperfecta: a pilot study

BACKGROUND

Osteogenesis Imperfecta (OI) is a heterogeneous group of connective tissue disorders, characterized by varying degrees of skeletal fragility. Patients experience a range of comorbidities, such as obesity, cardiovascular, and gastrointestinal complications, especially in adulthood. All aspects that could benefit from dietary intervention. The aim of this study was to evaluate the effects of a 6-months restricted Mediterranean Diet (rMD) on nutritional status in adult patients affected by OI. We carried out a 6-months longitudinal pilot study. 14 adults (median age: 35 years; 7 women; 7 OI type III) where recruited in 2019 among the members of As.It.O.I., the Italian Association of Osteogenesis Imperfecta. As.It.O.I. All the evaluations were performed at the University of Milan, Italy. The rMD provided a reduction of 30% from daily total energy expenditure. 45% of calories derived from carbohydrates, 35% from fat and 0.7-1.0 g/kg of body weight from proteins. Comparisons of continuous variables after 6 months of intervention were performed by the paired t-test. All P-values were two-tailed, and p < 0.05 was considered significant.

RESULTS

Patients showed significant improvement in anthropometric measurements (BMI = 30.5 vs 28.1 kg/cm2, p < 0.001; Body Fat % = 32.9 vs 29.9, p = 0.006; Waist circumferences = 83.6 vs 79.6 cm; p < 0.001; Arm Fat Area = 29.8 vs 23.07 cm2; p < 0.011) and energy expenditure (REE/kg = 27.2 vs 29.2 kcal/kg, p < 0.001). Glucose and lipid profiles improved (Δglycemia = - 8.6 ± 7.3 mg/dL, p = 0.003; ΔTC = - 14.6 ± 20.1 mg/dL, p = 0.036; ΔLDL = - 12.0 ± 12.1 mg/dL, p = 0.009). Adherence to the MD significantly increased, moving from a moderate to a strong adherence and reporting an increased consumption of white meat, legumes, fish, nuts, fruits and vegetables.

CONCLUSION

A rMD was effective in improving nutritional status and dietary quality in adults with OI. These results underscores the need to raise awareness of nutrition as part of the multidisciplinary treatment of this disease.

A scoping review of nutrition issues and management strategies in individuals with skeletal dysplasia

PURPOSE

Skeletal dysplasia are heterogeneous conditions affecting the skeleton. Common nutrition issues include feeding difficulties, obesity, and metabolic complications. This systematic scoping review aimed to identify key nutrition issues, management strategies, and gaps in knowledge regarding nutrition in skeletal dysplasia.

METHODS

The databases Ovid MEDLINE, Ovid EMBASE, Ebsco CINAHL, Scopus, and Cochrane Central Register of Controlled Trials and Database of Systematic Reviews were searched. Reference lists and citing literature for included studies were searched. Eligible studies included participants with skeletal dysplasia and described: anthropometry, body composition, nutrition-related biochemistry, clinical issues, dietary intake, measured energy or nutrition requirements, or nutrition interventions.

RESULTS

The literature search identified 8509 references from which 138 studies were included (130 observational, 3 intervention, 2 systematic reviews, and 3 clinical guidelines). Across 17 diagnoses identified, most studies described osteogenesis imperfecta (n = 50) and achondroplasia or hypochondroplasia (n = 47). Nutrition-related clinical issues, biochemistry, obesity, and metabolic complications were most commonly reported, and few studies measured energy requirements (n = 5).

CONCLUSION

Nutrition-related comorbidities are documented in skeletal dysplasia; yet, evidence to guide management is scarce. Evidence describing nutrition in rarer skeletal dysplasia conditions is lacking. Advances in skeletal dysplasia nutrition knowledge is needed to optimize broader health outcomes.

The patient clinical journey and socioeconomic impact of osteogenesis imperfecta: a systematic scoping review

BACKGROUND

Osteogenesis imperfecta (OI) is a rare heritable connective tissue disorder primarily characterised by skeletal deformity and fragility, and an array of secondary features. The purpose of this review was to capture and quantify the published evidence relating specifically to the clinical, humanistic, and economic impact of OI on individuals, their families, and wider society.

METHODS

A systematic scoping review of 11 databases (MEDLINE, MEDLINE in-progress, EMBASE, CENTRAL, PsycINFO, NHS EED, CEA Registry, PEDE, ScHARRHUd, Orphanet and Google Scholar), supplemented by hand searches of grey literature, was conducted to identify OI literature published 1st January 1995-18th December 2021. Searches were restricted to English language but without geographical limitations. The quality of included records was assessed using the AGREE II checklist and an adapted version of the JBI cross-sectional study checklist.

RESULTS

Of the identified 7,850 records, 271 records of 245 unique studies met the inclusion criteria; overall, 168 included records examined clinical aspects of OI, 67 provided humanistic data, 6 reported on the economic impact of OI, and 30 provided data on mixed outcomes. Bone conditions, anthropometric measurements, oral conditions, diagnostic techniques, use of pharmacotherapy, and physical functioning of adults and children with OI were well described. However, few records included current care practice, diagnosis and monitoring, interactions with the healthcare system, or transition of care across life stages. Limited data on wider health concerns beyond bone health, how these concerns may impact health-related quality of life, in particular that of adult men and other family members, were identified. Few records described fatigue in children or adults. Markedly few records provided data on the socioeconomic impact of OI on patients and their caregivers, and associated costs to healthcare systems, and wider society. Most included records had qualitative limitations.

CONCLUSION

Despite the rarity of OI, the volume of recently published literature highlights the breadth of interest in the OI field from the research community. However, significant data gaps describing the experience of OI for individuals, their families, and wider society warrant further research to capture and quantify the full impact of OI.

Anthropometrics of Polish children with osteogenesis imperfecta: a single-centre retrospective cohort study

BACKGROUND

Osteogenesis imperfecta (OI) causes a number of abnormalities in somatic development. The predominant symptoms are reduced bone mass and an increased risk of fractures as well as bone deformities and short stature. Due to the lack of causal treatment options, bisphosphonates are considered the gold standard of therapy. The aim of our study is to present selected anthropometric parameters (body weight, height, BMI) in children with type I and III of OI.

METHODS

We performed a retrospective analysis of medical records of patients with osteogenesis imperfecta type I and III confirmed by genetic testing. The study group included individuals admitted to the Department in 2020. We analysed the anthropometric parameters of 108 children (receiving and not receiving bisphosphonates treatment).

RESULTS

In the group of children with OI type I admitted for follow-up (group 1), the median weight percentile was 37, while in the group 2 it was 17. In the patients with OI type III (group 3), the median weight percentile was 0.1. The median height percentile in group 1 was 21, in group 2 it was 5, whereas in group 3 = 0.1. The differences in anthropometric measurements of the patients with OI type I and OI type III were statistically significant (p < 0.001). Among the analysed patients, an abnormal BMI was found in 41.67% of whom 37.78% were underweight, 48.89% were overweight and 13.33% were obese.

CONCLUSION

Considering prevalence of the disease, it is not only low stature but also abnormal BMI, and especially excessive body weight, that play an important role in the somatic development disorder.

Osteogenesis Imperfecta: The Impact of Genotype and Clinical Phenotype on Adiposity and Resting Energy Expenditure

CONTEXT

Mutations in type I collagen or collagen-related proteins cause osteogenesis imperfecta (OI). Energy expenditure and body composition in OI could reflect reduced mobility or intrinsic defects in osteoblast differentiation increasing adipocyte development.

OBJECTIVE

This study compares adiposity and resting energy expenditure (REE) in OI and healthy controls (HC), for OI genotype- and Type-associated differences.

METHODS

We studied 90 participants, 30 with OI (11 COL1A1 Gly, 8 COL1A2 Gly, 4 COL1A1 non-Gly, 1 COL1A2 non-Gly, 6 non-COL; 8 Type III, 16 Type IV, 4 Type VI, 1 Type VII, 1 Type XIV) and 60 HC with sociodemographic characteristics/BMI/BMIz similar to the OI group. Participants underwent dual-energy x-ray absorptiometry to determine lean mass and fat mass percentage (FM%) and REE. FM% and REE were compared, adjusting for covariates, to examine the relationship of OI genotypes and phenotypic Types.

RESULTS

FM% did not differ significantly in all patients with OI vs HC (OI: 36.6% ± 1.9%; HC: 32.7% ± 1.2%; P = 0.088). FM% was, however, greater than HC for those with non-COL variants (P = 0.016). FM% did not differ from HC among OI Types (P values > 0.05).Overall, covariate-adjusted REE did not differ significantly between OI and HC (OI: 1376.5 ± 44.7 kcal/d; HC: 1377.0 ± 96 kcal/d; P = 0.345). However, those with non-COL variants (P = 0.016) and Type VI OI (P = 0.04) had significantly lower REE than HC.

CONCLUSION

Overall, patients with OI did not significantly differ in either extra-marrow adiposity or REE from BMI-similar HC. However, reduced REE among those with non-COL variants may contribute to greater adiposity.

Eat, breathe, sleep with Osteogenesis Imperfecta

BACKGROUND

Although Osteogenesis Imperfecta (OI) affects the connective tissue causing extremely brittle bones with consequent skeletal deformities, it is important to go beyond bones. Indeed, the quality of life in OI does not only depend on bones status, as OI might affect also other important functions. We have therefore implemented a multidisciplinary study to assess lung function, breathing pattern, sleep quality and nutritional status in 27 adult OI type III and IV patients (median age: 34.6 years; 19 women; 14 type III).

RESULTS

According to nocturnal oxygen desaturation, two groups were identified: 13 patients with (OI_OSA, incidence: 48.2%) and 14 without (no_OSA) obstructive sleep apnea. The former was characterized by higher spinal and ribcage deformity, by more restrictive lung function, by paradoxical thoracic breathing in supine position, by rapid and shallow breathing, by higher body mass index, by longer neck and waist circumferences; by higher abdominal volume and by greater percentage of body fat mass, particularly localized in the trunk. The best predictor of OI_OSA was the negative value of the supine ribcage contribution to tidal volume, followed by the ratio between the neck and the waist circumferences with body height and the supine thoraco-abdominal volumes phase shift angle.

CONCLUSIONS

The pathophysiology of OI ensued a dangerous vicious circle, in which breathing, sleep and nutritional status are tightly linked, and they might all end up in negatively affecting the quality of life. The vicious circle is fed by some intrinsic characteristics of the disease (thoracic, cranial and mandibular deformities) and some bad daily habits of the patients (i.e. physical inactivity and low dietary quality). The former impacts on restricting the respiratory function, the latter makes Olers more prone to experience overweight or obesity. The main consequence is a high incidence of obstructive sleep apnea, which remains an underdiagnosed disorder in individuals with severe OI who are obese, with a neck to height ratio over than 31.6%, and characterized by paradoxical breathing in supine position. A multidisciplinary approach, including evaluations of breathing, sleep and nutrition, is required to better manage the disease and fulfil the maximizing well-being of OI patients.

Male but not female mice with severe osteogenesis imperfecta are partially protected from high-fat diet-induced obesity

Previously we have shown that young mice with a dominant severe form of osteogenesis imperfecta (OI), caused by mutated collagen type I, exhibit an altered glucose/insulin metabolism and energy expenditure along with elevated levels of osteocalcin, a bone-derived hormone involved in the regulation of whole-body metabolism. This study aimed to examine the long-term effects of a western diet in these OI mice. Male and female OI mice and wild type littermates (WT) were fed a high-fat diet (HFD) or a matched low-fat diet (LFD) for 26 weeks. HFD-induced obesity was observed in male and female WT and female OI mice, but not in male OI mice. HFD-fed WT and OI mice of both sexes developed hyperglycemia and glucose intolerance, but the degree of glucose intolerance was significantly lower in male and female OI mice compared to sex- and diet-matched WT mice. Indirect calorimetry revealed increased movement of male OI mice on HFD compared to LFD and, while HFD lowered energy expenditure in WT mice, energy expenditure was not changed in OI mice. Further, HFD-fed male OI mice demonstrated a diet-induced increased expression of the thermogenesis genes, Ucp1 and Pgc1α, in brown adipose tissue. On LFD, total and Gla-13 osteocalcin levels were similar in 30-week-old WT and OI mice, but on HFD, both were significantly higher in OI mice than WT. Thus, male OI mice respond to HFD with increased movement, energy expenditure, brown adipose tissue thermogenesis, and higher levels of osteocalcin, resulting in partial protection against HFD-induced obesity.

Temporomandibular Joint and Cervical Spine Mobility Assessment in the Prevention of Temporomandibular Disorders in Children with Osteogenesis Imperfecta: A Pilot Study

Osteogenesis imperfecta is a heterogeneous group of hereditary disorders of connective tissue diseases characterized by increased bone fragility, low growth, sometimes accompanied by abnormalities within the dentine, blue sclera, and partial or total hearing impairment. The changes may affect all joints, including the cervical spine and temporomandibular joints in the future, resulting in pain. The aim of the present study was to assess whether there is a relationship between the active range of motion of the cervical spine and the mobility of temporomandibular joints due to differential diagnosis in children with osteogenesis imperfecta, and to present a prevention algorithm for temporomandibular disorders. The study involved a group of 34 children with osteogenesis imperfecta, and the control group included 23 children (age 9.1 ± 3.8 years). Data were collected through an interview based on the author’s questionnaire, and the physical examination consisted in measuring the mobility of the cervical spine using an inclinometer (Cervical Range of Motion Instrument), the Helkimo scale, and linear measurements. In children with congenital bone fragility, there were acoustic symptoms from the temporomandibular joints more often than in healthy children. A correlation was found between the mobility of the cervical spine and temporomandibular joints in the study group. In the case of detecting irregularities in the temporomandibular joints, children were ordered to perform jaw-tongue coordination exercises.

Hearing loss in individuals with osteogenesis imperfecta in North America: Results from a multicenter study

Hearing loss (HL) is an extra-skeletal manifestation of the connective tissue disorder osteogenesis imperfecta (OI). Systematic evaluation of the prevalence and characteristics of HL in COL1A1/COL1A2-related OI will contribute to a better clinical management of individuals with OI. We collected and analyzed pure-tone audiometry data from 312 individuals with OI who were enrolled in the Linked Clinical Research Centers and the Brittle Bone Disorders Consortium. The prevalence, type, and severity of HL in COL1A1/COL1A2-related OI are reported. We show that the prevalence of HL in OI is 28% and increased with age in Type I OI but not in Types III and IV. Individuals with OI Types III and IV are at a higher risk to develop HL in the first decade of life when compared to OI Type I. We also show that the prevalence of SNHL is higher in females with OI compared to males. This study reveals new insights regarding prevalence of HL in OI including a lower general prevalence of HL in COL1A1/COL1A2-related OI than previously reported (28.3 vs. 65%) and high prevalence of SNHL in females. Our data support the need in early routine hearing evaluation in all types of OI that can be adjusted to the severity of the skeletal disease.

Cyclic pamidronate treatment for osteogenesis imperfecta: Report from a Brazilian reference center

Treatment of moderate and severe forms of osteogenesis imperfecta (OI) with cyclic pamidronate at the Reference Center for OI Treatment in Southern Brazil was studied. A retrospective cohort study was conducted from 2002 to 2012. Data were obtained during inpatient (drug infusion) and outpatient care. Clinical data, including the presence of blue sclerae, dentinogenesis imperfecta, history and site of the fractures, biochemical data, including calcium, phosphorus, and alkaline phosphatase levels, were systematically collected. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry (DXA). Forty-five patients (26 females) were included in the study, and the age of the patients at the time of diagnosis ranged from 1 to 144 months, with a median age (p25-p75) of 38 (5-96) months. Most cases presented OI-4 (51.1%), and the median age of the patients at the start of treatment was 3.3 years (25-75 percentiles: 0.5 - 8.7 years). Twenty-four patients (54.5%) had some adverse events or intercurrences during treatment, and the treatment compliance mean was 92.3% (± 10.7). The treatment with intravenous pamidronate has shown to be safe, well-tolerated, and effective in regard to the improvement of BMD and the reduction of the number of fractures in children and adolescents with OI.

Calcium intake improvement after nutritional intervention in paediatric patients with osteogenesis imperfecta

BACKGROUND

In several bone disorders, adequate calcium intake is a coadjuvant intervention to regular treatment. Osteogenesis imperfecta (OI) is a collagen disorder with a range of symptoms, ranging from fractures to minimum trauma, and it is typically treated with bisphosphonates. In the present study, we evaluate the impact of a nutritional intervention (NI) on dietary calcium intake and bone mineral density (BMD) in paediatric patients with OI.

METHODS

A nonrandomised clinical trial was designed with a NI. Dietary calcium intake, anthropometry and clinical features were assessed at baseline, including anthropometry, basal metabolic rate (BMR), BMD. In addition, a food guidance form was developed and sent to patients by mail. After 12 months, clinical features of patients were reassessed and compared with the baseline data.

RESULTS

Fifty-two children and adolescents were enrolled. Significant increases in total calcium intake (mg day^-1 ), percentage of adequate calcium intake (%) and number of cups of milk ingested were observed after NI. We detected a positive correlation between the variation of BMD and milk consumption in patients treated with bisphosphonate.

CONCLUSIONS

We observed an increase in calcium intake in patients with OI. This finding demonstrates the importance of nutrition therapy as part of a multidisciplinary treatment approach for bone health.

Mobility in osteogenesis imperfecta: a multicenter North American study

PURPOSE

Osteogenesis imperfecta (OI) is a genetic connective tissue disorder that causes bone fragility. Phenotypic severity influences ability to walk, however, little is known about ambulatory characteristics of individuals with OI, especially in more severe forms. The purpose of this work was to characterize mobility in OI using standard clinical assessment tools and determine if patient characteristics could be used to predict mobility outcomes.

METHODS

We collected mobility data at five clinical sites to analyze the largest cohort of individuals with OI (n = 491) to date. Linear mixed models were developed to explore relationships among subject demographics and mobility metrics.

RESULTS

Results showed minor limitations in the mild group while the more severe types showed more significant limitations in all mobility metrics analyzed. Height and weight were shown to be the most significant predictors of mobility. Relationships with mobility and bisphosphonates varied with OI type and type used (oral/IV).

CONCLUSION

These results are significant to understanding mobility limitations of specific types of OI and beneficial when developing rehabilitation protocols for this population. It is important for physicians, patients, and caregivers to gain insight into severity and classification of the disease and the influence of disease-related characteristics on prognosis for mobility.

Difference between Methods for Estimation of Basal Metabolic Rate and Body Composition in Pediatric Patients with Osteogenesis Imperfecta

Background/Aims: Osteogenesis Imperfecta (OI) is a bone disease characterized by bone fragility, deformities, and multiple fractures. The aim of this study was to compare the different methods of measuring the basal metabolic rate (BMR) and body composition (BC) in pediatric patients with OI. Methods: This cross-sectional study included 52 individuals with a median age of 9 (5.25–12.7) years. BMR was calculated by bioelectrical impedance analyses (BIA), predictive values according to age from the World Health Organization (WHO), a kcal/cm formula, and indirect calorimetry (IC). BC was assessed using the anthropometric calculation of percentage body fat (%BF) and lean mass (kg), BIA, and dual-energy X-ray absorptiometry (DEXA). Agreement among the methods was assessed using the Bland-Altman technique. Results: IC estimates of BMR were greater than BIA and lower than values obtained using the WHO and kcal/cm methods. Better agreement was observed using the WHO values for mild forms of OI and the kcal/cm formula for moderate-to-severe forms. For BC, DEXA estimates of %BF were higher and the lean mass was lower than the values obtained using BIA and anthropometry. Neither method agreed with the DEXA method results. Conclusions: Significant differences exist among the various methods used for measuring BMR and BC with regard to phenotypic differences between OI types.

Anthropometric and nutritional parameters in Egyptian children and adolescents with osteogenesis imperfecta

BACKGROUND/AIMS

Patients with osteogenesis imperfecta (OI) present with various degrees of short stature and nutritional disorders. Thus, we aimed to evaluate anthropometric and nutritional parameters in OI children and their variability among various types.

METHODS

Eighty-four patients with OI (types I, II, and IV) were subjected to the following anthropometric measurements: standing height (Ht), sitting height (SH), arm span, weight (Wt), and head circumference (HC), with calculation of Ht, SH, Wt, body mass index (BMI), and HC standard deviation scores (SDSs), and relative arm span. Triceps skinfold thickness (TSFT), subscapular skinfold thickness (SSFT), and mid upper arm circumference (MUAC) were measured, as well as dietary intake of macronutrients and calcium; also, energy requirements were calculated.

RESULTS

Ht SDS was reduced in OI-III and OI-IV compared to OI-I; SH SDS was reduced in OI-III compared to OI-I. HC SDS was more increased in OI-III than in OI-I and OI-IV. BMI SDS correlated with TSFT, SSFT, and MUAC. OI-III patients had the highest percentage of energy intake. The frequency of low macronutrient and calcium intake was highest in OI-III, while the frequency of low fat intake was highest in OI-I.

CONCLUSIONS

Anthropometric and nutritional parameters differ among OI types. Assessment of anthropometric measurements and nutritional status in OI patients is important.

Cross-sectional and longitudinal growth patterns in osteogenesis imperfecta: implications for clinical care

BACKGROUND

There is strikingly limited information on linear growth and weight in the different types of osteogenesis imperfecta (OI). Here, we define growth patterns further with the intent of implementing appropriate adaptations proactively.

METHODS

We report cross-sectional anthropometric data for 343 subjects with different OI types (144 children, 199 adults). Longitudinal height data for 36 children (18 girls, 18 boys) with OI type I and 10 children (8 girls, 2 boys) with OI type III were obtained.

RESULTS

In all cases, the height Z-scores were negatively impacted, and final height Z-scores were impacted the most. In type I, the growth velocities taper near puberty, and there is a blunted pubertal growth spurt. The growth velocities of children with type III decelerate before age 5 y; poor growth continues without an obvious pubertal growth spurt. Obesity is a concern for all patients with OI, with type III patients being the most affected.

CONCLUSION

The linear growth patterns, in addition to the marked increase in weight over time, indicate a need for lifestyle modifications early in childhood, especially a need for weight control. Further definition of the anthropometric measures in OI enables patients to begin modifications as early as possible.

Body Composition in Children and Adolescents with Osteogenesis Imperfecta

OBJECTIVE

To use peripheral quantitative computed tomography to determine the cross-sectional area (CSA) of subcutaneous fat and muscle (fat CSA, muscle CSA) in transverse forearm scans in patients with osteogenesis imperfecta (OI).

STUDY DESIGN

Fat and muscle CSA were quantified in 266 individuals (142 female) aged 5-20 years who had a diagnosis of OI type I, III, or IV and who had mutations in COL1A1 or COL1A2. Results were compared with those of 255 healthy controls.

RESULTS

In a subgroup of 39 patients with OI type I, % fat CSA correlated closely with total body percentage fat mass as determined by dual-energy x-ray absorptiometry (R(2) = 0.69; P < .001). In the entire study cohort, muscle CSA adjusted for age, sex, and forearm length was lower in OI type I and III than in controls (P < .05 each), but fat CSA was similar between OI types and controls. No relationship between the type of disease-causing mutation in the COL1A1 or COL1A2 genes and fat CSA or muscle CSA was found.

CONCLUSIONS

Children and adolescents with OI have low muscle size but a normal amount of subcutaneous fat at the forearm.

Study of the Determinants of Vitamin D Status in Pediatric Patients With Osteogenesis Imperfecta

OBJECTIVE

Vitamin D is essential to the development and maintenance of the skeleton, especially for children with bone disorders such as osteogenesis imperfecta (OI). We evaluated serum 25-hydroxyvitamin D (25-OHD) levels to assess the relationship between determinants of vitamin D status in pediatric patients with OI.

METHODS

This cross-sectional study evaluated sex, age, weight, height, body mass index, OI type, sunscreen use, season of assessment, sun exposure, vitamin D and calcium supplementation, bisphosphonate treatment, bone mineral density (BMD), milk and soda consumption, mobility, and time of sedentary activity. Levels of serum 25-OHD, calcium, parathyroid hormone (PTH), phosphorus, and alkaline phosphatase (ALP) were analyzed. Serum levels of 25-OHD were classified according to sufficient (>30 ng/ml or 75 nmol/L), insufficient (20-30 ng/ml or 50-75 nmol/L), moderately deficient (20-10 ng/ml or 50-25 nmol/L), and severely deficient (<10 ng/ml or 25 nmol/L).

RESULTS

Fifty-two patients were included and 46 (88.4%) were classified as having insufficient or deficient 25-OHD. An inverse correlation between serum 25-OHD and time of sedentary activity (r = -0.597, p < 0.001) and a positive correlation with height (r = 0.521, p = 0.046) and whole body BMD (r = 0.586, p = 0.022) were observed. A significant difference between the number of glasses of milk consumed (p = 0.010) was observed.

CONCLUSION

To optimize bone health, patients with OI need to be educated regarding habits that can improve serum 25-OHD levels, such as a reduction in periods of inactivity, the importance of sun exposure, and increasing consumption of milk and fortified dairy products.