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A clinical trial carried out during the autumn/winter season in 46 institutionalized elderly subjects (35 women, 11 men) (group mean age = 83 +/- 2 years) revealed a severe deficiency in vitamin D in these subjects (25-hydroxyvitamin D level less than or equal to 3 ng/ml). After oral administration of 100,000 IU of vitamin D3, an increase in 25-hydroxyvitamin D levels above the 10 ng/ml threshold was observed and maintained for three months. A second dose, administered after 3 months, made it possible to sustain this level. No sign of toxicity was detected, notably no trace of hypercalcemia. In contrast, no change in the deficit (25-hydroxyvitamin D level less than or equal to 3 ng/ml) was seen in the placebo population. Three-monthly administration of the moderate dosage of 100,000 IU of vitamin D3 all year round would offer a simple, effective and risk-free system to counteract vitamin D deficiency in the elderly and of preventing the risk of osteomalacia, thus reducing the incidence of fractures.

25-hydroxyvitamin D (25 OH vit D) plasma levels were measured according to the method of Preece et al. in 2 groups of subjects. Group 1 consisted of 10 adult controls in whom 25 OH vit D levels were measured 11 times at 1 month intervals. Group 2 consisted of 93 mother-child pairs including 71 neonates with normal plasma calcium levels (group 2a) and 22 with hypocalcemia (group 2b). In mothers, 25 OH vit D levels (group 2a: 12 ng/ml +/- 6.4 SD, n = 71; group 2b: 9.5 ng/ml +/- 3.5 SD, n = 22) were lower than in controls (25.1 ng/ml +/- 7.9 SD). In neonates, 25 OH vit D levels were correlated with those of their mothers; however there was no significant difference in neonates with or without hypocalcemia (group 2a: means = 11.9 ng/ml +/- 6.1 SD, n = 71; group 2b: means = 10 ng/ml +/- 4.1 SD, n = 22). 25 OH vit D levels in adults of group 1 were significantly correlated with exposure to sunlight, while no significant correlation was found in the mothers-children pairs of group 2. These results confirm the relationship of 25 OH vit D plasma levels of neonates with their mothers' but do not support the concept of a relation between low plasma levels in mother and the occurrence of hypocalcemia in neonates.

Over a 3 years period, PTH, 25 OHD, calcium and phosphate levels were measured in all patients admitted to a department of Internal Medicine with abnormal phospho-calcic metabolism or bone disease. The diagnostic value of iPTH was analysed, especially in cases of hyper- and hypocalcaemia. In hypercalcaemia, the iPTH did not differentiate between the two main differential diagnoses: hyperparathyroidism and cancer. In patients with a negative calcium balance, the iPTH level is often raised and many help towards diagnosis. However, it should first of all orientate the clinician towards the detection of renal failure which is a common cause of this condition.

A radiocompetitive estimation of 25-hydroxyvitamin D in human serum is described. After extraction, a stage of purification by chromatography on a Sephadex LH 20 column permits separation of 25-hydroxyvitamin D from Vitamin D and other metabolites. The reaction of radiocompetition uses as tracer tritiated 25-hydroxycholecalciferol and as source of binding protein, rat renal cytosol. The characteristics of the binding protein and the presence in human plasma of significant quantities of 24,25-dihydroxyvitamin D render necessary the chromatographic stage. This technic permits one to measure simply and specifically 25-hydroxyvitamin D in the human serum, of which normal levels (average +/- standard deviation) are 12.88 +/- 5.42 microgram/l 3.2.10(-8) + 1.35.10(-8) mol/l).

Serum levels of 25 OH-D, Calcium, Phosphorus and Alkaline phosphatase were measured in 53 children. These children, immigrants for 3/4, 3 to 6 years old, were in good health, and usually followed in a medical advice of PMI in the center of the city. During the month of february, march, april, the half of immigrant children have a serum 25 OH-D deficiency and high alkaline phosphatase, when european children have a normal 25 OH-D level and low alkaline phosphatase. After a stay in their origin country, in september, october, the children come back with a normal 25 OH-D level. Difference between winter and autumn is very significative. The risk factors of a vitamin D deficiency are studied.

Besides its well known anti-rachitic properties, vitamin D has numerous in vitro and in vivo actions on the proliferation-differentiation of epidermal and cancer cells, as well as on the recruitment, differentiation and activities of the immune cells. Even though numerous association studies have suggested a possible link between a low vitamin D status and the risk of developing tumoral, auto-immune, neurologic or cardiovascular diseases, further data have proven to be more discordant and at best modest. In addition, the range of vitamin D doses or status active on these extra-skeletal pathologies remains poorly defined, between insufficiency and overload. Looking forward to clearly needed randomized intervention studies, optimal vitamin D status and intakes remain best defined on the basis of the vitamin D indisputable effects on calcium homeostasis and skeletal mineralization.

Le déficit et l’insuffisance en vitamine D, définis respectivement par des concentrations sériques de 25 hydroxyvitamine D (25OHD) inférieures à 20 ng/ml et entre 20 et 30 ng/ml, sont des situations très fréquentes qui sont associées à une augmentation du risque de développer différentes pathologies, pas seulement osseuses. Les effets d’une supplémentation en vitamine D sur la diminution du risque de fractures et de chutes sont documentés par différentes études d’intervention. Les autres effets potentiels extra-osseux de la vitamine D sont principalement documentés par des études observationnelles et expérimentales. Même s’il n’existe pas encore de consensus sur les besoins en vitamine D, tous les experts s’accordent pour considérer que les AJR (200 UI/J en France) sont très insuffisants et doivent être augmentés. Cet article aborde successivement le métabolisme de la vitamine D et ses effets, la définition du statut vitaminique D basée sur la concentration sérique de 25OHD, les indications du dosage de la 25OHD (qui ne doit pas être prescrit à tout le monde) et propose des modalités de traitement.

In Quebec, cancer is the principal cause of mortality. This epidemiologic research program includes two components. The first component takes place at the "Institut national de santé publique du Québec" and involves surveillance and evaluation of practices in oncology with the aim of providing the Quebec Ministry of Health with some of the evidence needed to determine its policies in cancer control. The second component takes place at the "Unité de recherche en santé des populations (URESP)" of Laval University and is devoted to studying the etiology and prevention of breast cancer. This paper focuses on this second research component which uses mammographic breast density as an intermediate biomarker to study the causes of breast cancer and strategies to prevent it. Breast cancer risk is much higher among women with very dense breasts than among those with little or no breast density. Recently, we were among the first to show that women with high vitamin D or calcium intakes have less breast density than those with low intakes, especially among premenopausal women. Furthermore, we have confirmed that breast density was increased among premenopausal women with high levels of IGF-I and low levels of IGFBP3 which is consistent with the observed effect of these molecules on breast cancer risk. Studies are now being conducted to assess whether breast density varies according to blood levels of vitamin D and of additional growth factors, as well as to genetic polymorphisms involved in the pathways of vitamin D, calcium and growth factors. The increase in vitamin D and calcium intakes may prove to be a safe and inexpensive approach to breast cancer prevention; this possibility should be carefully examined as quickly as possible.

Objectives: To evaluate vitamin D status in two subgroups of the Lebanese aged population. To compare results with reference values observed in healthy young volunteers., Methods: Fifty aged institutionalized patients (25 men and 25 women) and 51 aged ambulatory subjects (25 men and 26 women) underwent the following explorations during winter: serum 25-OH vitamin D, parathyroid hormone, corrected serum calcium, phosphorus, creatinine, and alkaline phosphatases and urinary calcium/creatinine. Serum 25-OH vitamin D and urinary calcium/creatinine were also measured in 34 healthy young volunteers., Results: Serum 25-OH vitamin D levels in 25 ambulatory subjects (49%) and 30 institutionalized patients (60%) were below 10 ng/ml. There was non significant difference in 25-OH vitamin D levels between the ambulatory and institutionalized aged populations, nor between aged women and aged men. Parathyroid hormone, alkaline phosphatases and urinary calcium/creatinine levels were higher in the institutionalized population than in the ambulatory population (p = 0.07; p = 0.0001; p = 0.0001 respectively). Aged women had higher parathyroid hormone and calcium/creatine levels than aged men (p = 0.005; p = 0.005 respectively). Finally, in the young population, 25-OH vitamin D was higher than in the aged institutionalized and ambulatory populations (p = 0.0001 and p = 0.0009 respectively). An inverse non-significant correlation (r = -0.16) was found between parathyroid hormone and 25-OH vitamin D., Conclusion: Our results show that even in a sunny country like Lebanon, vitamin D deficiency is often observed. The degree of deficiency probably lies between that observed in Europe and the United States. It could be related to low vitamin D diet.

Background: Administration of oral vitamin D supplements has been the usual strategy used in France for the prevention of rickets. But this strategy needs reevaluation since the fortification of infant formulas with vitamin D is authorized in this country. We report the effects of oral daily supplements of vitamin D on the calcium metabolism and vitamin D status of infants receiving or not fortified milk during the first trimester of life., Population and Methods: Circulating levels of 25-hydroxyvitamin D (25-(OH)D) were measured: 1) in 64 infants aged 1 to 4 months, seen as outpatients between February and October, given oral vitamin D2 (theoretically 1,000 IU/d) and fed infant formulas, fortified or not with vitamin D; 2) in healthy neonates born to unsupplemented (n = 48) or supplemented vitamin D mothers (n = 22), between April and July, followed from birth (n = 70) to 3 months of age (n = 52), fed fortified milk, and given either 500 or 1,000 IU/D of vitamin D2. Serum calcium, phosphate, intact parathyroid hormone levels and alkaline phosphatase activities were simultaneously measured in this second study., Results: In the first study, the infants who had been seen during the summer and fed fortified milk had 25-(OH)D levels higher than those seen during the winter and fed the unfortified formulas (37.0 +/- 11.2 ng/mL vs 29.1 +/- 9.7 ng/mL, P = 0.013). But when daily supplements of vitamin D2 were strictly controlled (second study), all infants fed the fortified milk had 25-(OH)D levels within the adult range (10 to 37 ng/mL) at 1 and 3 months of age, whatever their vitamin D status at birth and although these infants were seen during the summer. No difference was found between infants given 500 or 1,000 IU/d as regards their mean serum calcium, phosphate and alkaline phosphatase activities. In addition, the percentage of infants with calcemia above 2.60 mM/L was even lower with the 1,000 IU/d vitamin D dosage than with the 500 IU/d dosage., Conclusions: Daily supplements of vitamin D2 (500 to 1,000 IU/d) during the first trimester of life do not appear to induce a significant vitamin D overload when fortified milk is given to the infants. These supplementations may thus be maintained, especially when neonates are at risk of vitamin D deficiency.

Résumé: Objectif: L’objectif de cette revue est de connaître le lien existant entre le cancer du sein et la vitamine D, qu’elle soit synthétisée par la peau ou apportée par l’alimentation ou par une supplémentation. Matériel et méthodes: Les articles pris en compte ont été extraits de la base de données Pubmed de 1998 à 2012. Les mots clés utilisés ont été : ű 25-hydroxyvitamin D Ƈ, ű breast cancer recurrence Ƈ, ű breast cancer risk Ƈ, ű serum levels of vitamin D Ƈ, ű vitamin D intake Ƈ. Au total, 37 articles ont été retenus. Résultats: L’exposition solaire, via la synthèse de vitamine D, est associée à une diminution du risque de cancer du sein. Une telle baisse semble également probable pour les apports alimentaires ainsi que pour la supplémentation en vitamine D à raison d’une dose supérieure à 400UI/j. Une relation inverse entre le taux sanguin de 25-hydroxyvitamine D (25-OH-D) et le risque de cancer du sein a inconstamment été retrouvée. L’augmentation de la 25-OH-D sérique semble être associée à une diminution du risque de récidive du cancer du sein. Conclusion: Des recommandations concernant une supplémentation en vitamine D pourraient être établies, mais nécessitent d’être étoffées par des recherches complémentaires. [ABSTRACT FROM AUTHOR]

This study of the three main vitamin D metabolites namely 25-(OH) D, 24, 25-(OH) 2D and 1, 25-(OH) 2D includes (1) a summary of the usual assay techniques, (2) a discussion about the concentrations and the role of these metabolites during the neonatal and childhood periods, (3) a report of the results obtained during the past seven years in our laboratory with comments on the interest and limits of these assays for the diagnosis of different types of rickets.

Between october 1976 and march 1978, 160 patients with low 25-OH-D plasma levels were observed (25-OH-D less than 7 ng/ml). In this population, a high frequency of asthenia, anorexia, vertebral demineralization were noticed. Mean plasma level of calcium was significantly lower than controls. Mean plasma level of alkalin phosphatases was significantly higher than controls. These patients presented a varied pathology. These diseases were probably responsible for the low 25-OH-D plasma level. The mechanisms were varying, but anorexia and sun exposure defect were likely the main cause of the low 25-OH-D plasma level.

The authors report on a new case of severe hypercalcaemia induced by prolonged oral treatment with high doses of vitamin D2. (6 mg/day for 9 months). Blood calcium level did not return to normal until 6 months after the drug was discontinued. The plasma concentration of 25 (OH) D was more than three times the normal value and remained very high throughout the observation period. The plasma concentration of 24, 25 (OH)2 D was slightly raised during treatment but became normal after 15 days, while that of 1,25 (OH)2 D, the active form of vitamin D, remained normal throughout, suggesting that the pathogenesis of vitamin D-induced hypercalcaemia is probably complex.

Copyright of Gériatrie et Psychologie Neuropsychiatrie du Vieillissement is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Objective. – To analyse the status of vitamin D and the influence of a supplement of vitamin D in neonates and infants during the first 6 months of life in the african equatorial environnement of Gabon. Design. – Clinical (weight, height, head circumference, and diseases) and biological (calcemia, phosphatemia, serum alkaline phosphatase activity and plasma 25-hydroxyvitamin D levels) parameters were compared between 2 groups of children: group 1: 41 infants receving a daily supplement of 1000 IU of vitamin D, and group 2: 38 infants without vitamin D supplement. Results. – No significant differences were observed between the 2 groups concerning clinical and biological parameters. In particular plasma levels of 25-hydroxyvitamin D were normal and similar in both groups. Conclusion. – A vitamin D supplement appears to be useless in 0 to 6 months infants living in Gabon. [Copyright &y& Elsevier]

Copyright of Médecine is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gériatrie et Psychologie Neuropsychiatrie du Vieillissement is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Résumé: Un projet d'arrêté ministériel inscrivant le cholécalciférol, c'est-à-dire la vitamine D3 (VD3), dans la liste des perturbateurs endocriniens (PE) est à l'origine de débats en France. L'objectif de notre article était de préciser les arguments scientifiques pour et contre l'inscription de la VD3 dans la liste des PE, qui semble être initialement due à son utilisation à très forte dose comme raticide/rodenticide dans certains pays. Premièrement, le cholécalciférol ne peut être défini comme une substance exogène, terme utilisé dans les différentes définitions des PE, car il est largement synthétisé dans la peau suite à l'exposition aux UVB. Deuxièmement, il n'existe aucune publication dans la base de données PubMed en faveur d'une inscription de la VD3 dans la liste des PE. La requête « vitamin D AND endocrine disruptor » retrouvait 33 références au 10 mars 2022, la plupart évoquant des perturbations du métabolisme de la vitamine D par les PE. Troisièmement, un grand nombre d'études concluent, au contraire, que la VD3 a des effets bénéfiques sur de nombreuses fonctions altérées par les PE. Plus largement, nous alertons sur le fait qu'apprendre que la VD3 pourrait être règlementairement considérée comme un PE pourrait occasionner, auprès du grand public, une défiance vis-à-vis de la supplémentation en vitamine D, ce qui n'est pas souhaitable en termes de santé publique car de nature à aggraver la prévalence déjà trop élevée des individus carencés en vitamine D. Il est encore temps d'éviter cette décision aberrante et non fondée. A French ministerial decree planning to include cholecalciferol, i.e. vitamin D3 (VD3), in the endocrine disruptors (ED) list has generated a lot of concerns in French physicians and scientists. The aim of the present article was to discuss the scientific rationale that may support or not this decision, which seems to be due to the use of VD3 overdose as a rodenticide in some European countries. First, it is noticeable that cholecalciferol is not an "exogenous substance", a term used in all the definitions of ED, as it is largely synthesized in the skin after UVB rays exposure. Second, we did not find any published article that may support the inclusion of VD3 in the ED list. The request "vitamin D AND endocrine disruptor" reported 33 references in the PubMed database on March, 10, 2022, most of them discussing disturbances of vitamin D metabolism by EDs. Third, a large amount of studies conclude that VD3 has or may have beneficial effects on many functions that are known to be altered by EDs. In addition, we warn that learning that VD3 could be legally considered as a PE may cause the general public to mistrust vitamin D supplementation, which is not desirable in terms of public health as it may increase the already too high prevalence of vitamin D deficient individuals. We consider the aberrant decision of including cholecalciferol in the ED list should be rapidly invalidated before being effective in France and possibly disseminated in the European Union. [ABSTRACT FROM AUTHOR]

Summary: Aims: The aim of the study was to assess compliance with the current recommendations of prophylactic prescription of vitamin D via a multicentric cross-sectional epidemiological survey of 3240 children under 6years of age. Method: Parent questionnaires and data from the health records of children presenting to the emergency departments of 25 teaching hospitals and hospital centers provided information on the children''s characteristics, their prescriptions, and other vitamin D intake. Based on the currently applicable recommendations, intakes of 600–1200IU/day — 900–1500 IU/day for children with pigmented skin and/or premature and/or hypotrophic children — are considered adequate. Results: In 1606 infants, 9.8% of the prescriptions were below and 23.7% were above the recommendations; in 1256 children between 18 months and 5years of age, 53.4% of the prescriptions were below and 5.1% were above the recommendations. Children at risk, those from the southern half of France, and those between 18months and 5years of age were more likely to receive a prescription below the recommendations; their risk of receiving a prescription above the recommended guidelines was smaller. Of the children aged between 61 and 71months, 85% had not received any prescription at all during the previous 12months. These results were compared with the laboratory data collected from a subsample of children. There was a significant correlation between the adequacy of the prescription and the biological vitamin D status both for 25-hydroxyvitamin D (25-OH-D) serological concentrations and for calciuria. Conclusions: Only 66.6% of the prescriptions in children between 0 and 18months of age and 41.5% in children between 19months and 5 years of age comply with the recommendations; 53.4% of the prescriptions in the latter age group are below the current recommendations. [Copyright &y& Elsevier]

Introduction. Without magnesium, vitamin D cannot be converted to its biolo- gically active form, a relationship that is often overlooked. Objective. The aim of this study was to estimate the frequency of hypovitaminosis D and that of hypomagnese-mia on the one hand, and to analyze the relationship between vitamin D status, magnesium, and plasma parathormone on the other hand. Population and methods. A retrospective descriptive-analytical,and epidemiological study was conducted on a 112 apparently healthy young adult subjects. For this purpose, bioassays of 25-hydroxy-vitamin D, magnesium and plasma parathormone were performed. Results. The frequency of hypovitaminosis D (serum 25-hydroxyvitamin D  30ng/mL) represented 88.39%. Hypomagnesemia affeted 43.75% of the studied population. A highly significant positive correlation was noted between plasma magnesium levels and vitamin D status of the subjects (R= 0.849; P = 0.000), whereas, a very significant negative correlation was observed between magnesium and plasma parathormone levels (R=-0.92 ; P = 0.000). Conclusion. A high frequency of hypovitamin D, a significant frequency of hypomagne-semia, and a positive correlation between plasma magnesium and vitamin D status are observed. Magnesium level is a determining factor in the variation of serum calcidiol concentrations that should be considered in the assessment of vitamin D status.

Abstract: The main cause of osteomalacia in adults is a severe and prolonged loss in vitamin D; today, it is easily recognized by 25-hydroxyvitamin D assay [25(OH)D]. The clinical context, laboratory abnormalities of the calcium-phosphate metabolism, abnormalities on medical imaging studies (radiographs, bone scan), sometimes, a very low density measured on bone densitometry can raise the possibility of mineralization disorder such as osteomalacia. Diagnosis can be confirmed by histomorphometric analysis of transiliac bone biopsy performed after double tetracyclin labeling. Cause for vitamin D deficiency should be searched and treated. Simple supplementation with vitamin D can cure these patients. Rare forms of osteomalacia, termed vitamin D-resistant rickets, are due to a genetic abnormality on an enzyme (Prader''s pseudo-deficient rickets or type-1 vitamin D-resistant rickets due to the absence of alpha 1-hydroxylase) or an abnormal vitamin D receptor (VDR, type 2 vitamin D-dependent rickets) creating a resistance to the action of vitamin D in target organs. In this particular form, the treatment is difficult; it necessitates the use of high pharmacological doses of vitamin D in addition to a high calcium supplementation. [Copyright &y& Elsevier]

Abstract: Objectives. – Rickets can still be observed among children and adolescents living in Europe, and a significant proportion of healthy children and adolescents presents serum 25–hydroxyvitamin D (25-(OH)D) values below the threshold indicating an insufficient vitamin D status. We have previously proposed detecting at risk individuals with a decision-making abacus based on questionnaires assessing calcium and vitamin D intakes and vitamin D production via sun exposure. Methods. – We tested the validity of this detection by receiver operating characteristic (ROC) analysis, using, as the main outcome measure, the serum 25-(OH)D values measured at the time of questionnaires presentation. In addition, the original questionnaires have been simplified by limiting the items to those significantly associated with 25-(OH)D values. The study group included 116 children and adolescents aged 6 to 17 years, seen at the end of the winter, and randomized in 2 groups: “ test ”, for the development of the tool (n =75), and “ validation ” (n =41). Results. – The present analysis shows that the proposed decision-making abacus has a sufficient ability to detect children at risk of vitamin D deficiency (with 25-(OH)D values below 10 ng/ml): area under the curve 0.748/0.895, sensibility 0.71/0.83, and specificity 0.62/0.80, in the test and validation groups, respectively. Conclusion. – These questionnaire and abacus may offer a substantial help to detect children and adolescents at risk of vitamin D deficiency in both a private office or hospital environment. [Copyright &y& Elsevier]

The 25-hydroxyvitamin D (25OHD) serum concentration should not be measured to everybody but recommendations for this measurement in several clinical situations are available from numerous guidelines and expert positions. It can be proposed to measure 25OHD in diseases where a target range of 25OHD concentrations associated with better outcomes is defined with a sufficient level of evidence, and when this target concentration is difficult to reach without previous measurement (or may be exceeded in case of too large doses are provided). Many National and International Medical Societies recommend to measure 25OHD at least in any situation of « bone fragility » (defined by a low bone mineral density and/or a low energy fracture), in malabsorptions, in chronic kidney disease, in any « phosphocalcic pathology, in patients with clinical signs of profound vitamin D deficiency or excess, and, more generally in any biological exploration of calcium/phosphorus metabolism that includes the measurement of PTH. Although these recommandations may seem discordant with the recent French restriction in the reimbursment of 25OHD measurement, they may still be reimbursed.

Causes of secondary osteoporosis represent 10 to 20% of all postmenopausal osteoporosis causes. Accordingly, laboratory testing needs to be performed to exclude those conditions before any therapeutic strategy. It is particularly the case in women with a recent fragility fracture or in otherwise healthy women with unexplained low bone mineral density. While there is no consensus for a simple testing strategy, evaluation of serum and urine calcium, phosphate, creatinine with 25-hydroxyvitamin D and complete blood count including erythrocyte sedimentation rate and possibly protein electrophoresis and serum thyroid-stimulating hormone could be recommended. [Copyright &y& Elsevier]