The Association Among Vitamin D status, Bone Geometry and Muscle Structure in 14 to 18 y Female Adolescents with Usual Intake of < 2 Servings of Milk and Alternatives per Day
Notice bibliographique
Résumé
The associations among vitamin D status, based on serum 25‐hydroxyvitamin D (25OHD), and bone geometry and muscle structure in adolescents is under investigated. The objective was to explore the relationships among serum 25OHD and bone and muscle parameters of the lower leg and forearm in female adolescents with usual intake of < 2 servings of milk and alternatives per day. Healthy adolescents (14 to 18 y, n=50) from the Greater Montreal area participating in a trial (NCT02236871) were divided into three groups according to serum 25OHD level (<50, n=15; 50–74.9, n= 25; and ≥75 nmol/L, n=10) at baseline. Trabecular and cortical volumetric bone mineral density (vBMD), cortical thickness (CT) and bone area (BA) of the radius (4% and 66% sites), the tibia (4%, 38% and 66% sites) and muscle cross‐sectional area and density (66% sites) were obtained using peripheral quantitative computed tomography (pQCT, XCT‐2000; Stratec). Fasted venous blood was sampled to measure serum 25OHD concentration (Liaison, Diasorin). Lean mass and fat mass were acquired using dual‐energy X‐ray absorptiometry (DXA; Hologic Discovery QDR series). This was followed by standardized anthropometry, individual topological angle (ITA) as well as 24‐hour recall for dietary calcium, vitamin D, total energy and protein intake. All data reflect baseline only. Differences among 25OHD level groups for bone and muscle parameters were tested using mixed model ANOVA with post‐hoc Bonferroni adjustment. Data are presented as mean ± SD unless otherwise stated. Multivariate linear regression models, adjusting for age, height, fat mass, lean mass, ethnicity, skin color and vitamin D intake, were applied to evaluate the association between 25OHD and bone parameters. Participants (n= 50) had a mean age of 16.4 ± 1.5 y and a BMI of 21.7 ± 3.1 kg/m 2 (). No significant differences among the groups were obtained for any of the bone parameters except for trabecular vBMD at the 4% tibia, where the group with 25OHD levels of >75 nmol/L revealed greater vBMD values than the group with less than 50 nmol/L (). Muscle parameters did not differ among vitamin D status groups. After applying multivariate linear regression models, the association between 25OHD and bone parameters remained significant for trabecular vBMD of the 4% tibia (). Findings of this study support a beneficial role of vitamin D status in skeletal health of female youth. Further longitudinal studies are needed to determine whether changes in vitamin D status over time associates with peak bone mass. Support or Funding Information Supported by a contribution from the Dairy Research Cluster Initiative (Dairy Farmers of Canada, Agriculture and Agri‐food Canada, the Canadian Dairy Network and the Canadian Dairy Commission), Canada Foundation for Innovation and Canada Research Chairs Program Descriptive characteristics of the study population 25OHD Levels (nmol/L) Total Sample, n = 50 < 50, n =15Means ± SD 50 – 74.9, n = 25Means ± SD ≥ 75, n = 10Means ± SD 25OHD (nmol/L) 63.7 ± 27.8 38.9 ± 7.6 60.3 ± 6.4 109.2 ± 25.4 Age (y) 16.4 ± 1.5 16.6 ± 1.4 16.4 ± 1.7 16.1 ± 1.3 Ethnicity, white (%) 66 40 66.7 100 Height (cm) 165.0 ± 7.0 165.9 ± 7.1 164.0 ± 7.3 166.3 ± 6.3 Weight (kg) 60.7 ± 10.8 62.8 ± 12.6 58.8 ± 10.2 62.5 ± 9.9 BMI (kg/m 2 ) 22.2 ± 3.2 22.7 ± 3.5 21.8 ± 3.1 22.6 ± 3.1 Fat Mass (kg) 16.9 ± 5.6 18.0 ± 5.1 15.9 ± 5.6 17.7 ± 6.4 Lean Mass (kg) 42.5 ± 6.9 42.4 ± 7.8 40.6 ± 5.7 42.6 ± 4.7 Vitamin D Intake (IU/d) 108.7 ± 118.4 128.7 ± 106.1 133.6 ± 88.9 128.1 ± 95.2 Calcium Intake (mg/d) 741.4 ± 445.9 705.2 ± 469.6 727.5 ± 449.5 830.8 ± 435.0 Protein Intake (g/d) 73.3 ± 38.6 65.3 ± 36.1 77.8 ± 43.4 74.2 ± 30.4
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Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».