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Background: Previous studies report that maternal vitamin D exposure during pregnancy is associated with offspring later-life bone health. A study in the Vitamin D in Pregnancy (VIP) cohort reported sexually dimorphic effects of maternal 25-hydroxyvitamin-D (25(OH)D) and offspring fracture profiles at 10 years of age. We, therefore, aimed to determine associations between maternal 25(OH)D status and offspring fracture risk at 16 years of age in this cohort., Methods: In total, 475 mother-child pairs were recruited to the VIP study in southeastern Australia. Maternal serum samples were obtained at recruitment (<16 weeks' gestation) and/or 28-32 weeks' gestation and analysed for 25(OH)D. Radiologically-confirmed incident fractures in children were ascertained from date of birth (2002-2004) until July 16, 2019. Cox proportional hazard models were used to determine associations between maternal 25(OH)D and childhood fracture risk, and final models included maternal age at recruitment, offspring sex, birth weight, gestation length and season of 25(OH)D sample., Results: Data were available for 400 children (mean age 16.1 years). There were 122 (30.5%) children who sustained at least one fracture. Higher maternal 25(OH)D (per 10 nmol/L) in early gestation was associated with a decreased fracture risk in boys (HR 0.87; 95% CI: 0.77, 0.99); the pattern was reversed in girls (HR 1.10; 95% CI 1.00, 1.22). At late gestation, higher maternal 25(OH)D was associated with an increased fracture risk in girls (HR 1.14; 95% CI: 1.04, 1.24)., Conclusions: While our findings must be interpreted within the constraints of our limitations, we report that the contradictory risk profiles observed at early childhood in this cohort remain in adolescence., (© 2024. The Author(s).)

Breast milk is an emerging matrix for vitamin D assessment of breastfed infants and their mothers. It is considered a more reliable indicator of infant intake than the assessment of maternal circulating vitamin D. With the improved sensitivity of mass spectrometry-based technologies, this method principle has been the recent mainstay for the quantitation of various vitamin D metabolites in breast milk for population-based clinical trials. There are still several areas across the total testing process (pre-analytical, analytical and post-analytical) to be defined and harmonised to translate breast milk vitamin D measurement by liquid chromatography-tandem mass spectrometry (LC-MS/MS) from population-based research to routine clinical use and public health applications. Pre-analytically, the determination of the best form of vitamin D to measure in breast milk requires more evidence. Analytically, standardisation of the methods to allow for comparability of results is required. Post analytically, breast milk vitamin D decision limits are needed to turn the individual numerical outputs into clinically meaningful results. This review aims to synthesise the current evidence and utility of measurement of breast milk vitamin D by LC-MS/MS and to lead a future discussion on best practices to allow for its clinical utility beyond its current research-based use., (Copyright © 2021 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Previously we have reported an association between maternal vitamin D and offspring bone as measured by dual-energy X-ray absorptiometry. It is plausible that shared genetics might confound associations between maternal vitamin D in pregnancy and offspring bone measures. We aimed to determine whether such associations are independent of maternal bone quality. Data for this analysis were derived from 168 mother-child pairs who returned at the 11-year follow-up of the vitamin D in pregnancy study. Gestational 25-hydroxyvitamin D [25(OH)D] was assessed by radioimmunoassay in early pregnancy at recruitment (before 16 weeks gestation) and later in pregnancy (28-32 weeks gestation). Bone quality was assessed for mothers and children at the calcaneus using quantitative ultrasound (Achilles InSight, GE). Speed of Sound (SOS), Broadband Ultrasound Attenuation (BUA) and Stiffness Index (SI) were the outcomes of interest. Maternal 25(OH)D in early pregnancy was associated with offspring SOS (β 1.46 m/s 95% CI 0.12, 2.8). When separated by sex, there was no association between maternal 25(OH)D at recruitment and offspring SI (r =  - 0.05, p = 0.68), SOS (r = 0.11, p = 0.34) or BUA (- 0.09, p = 0.43) in girls. In boys, maternal 25(OH)D at recruitment was associated with SI (r = 0.21, p = 0.048), and SOS (r = 0.24, p = 0.03) but not BUA (r = 0.10, p = 0.37). Adjustment for the offspring factors and respective maternal QUS parameter did not attenuate associations between maternal 25(OH)D in early pregnancy with offspring SOS, nor SI. There was no association with BUA. Furthermore, there was no association between maternal 25(OH)D in late pregnancy with any offspring QUS parameter. These prospective data support existing evidence of a positive relationship between maternal 25(OH)D levels during early pregnancy and measures of bone health of offspring in childhood, independent of maternal bone phenotype.

Previously we have demonstrated an association between maternal serum 25-hydroxyvitamin D (25(OH)D) during pregnancy and knee-heel length in offspring at birth. However, it is unknown whether maternal serum 25(OH)D is associated with bone measures in childhood. Thus, we aimed to examine associations between 25(OH)D at two stages of pregnancy and offspring bone measures at 11 years. Women were recruited from a single antenatal clinic in Victoria, Australia before 16 weeks gestation and provided two serum samples to determine 25(OH)D status at recruitment and 28-32 weeks gestation. Children and their mothers were followed up at 11 years of age. Children undertook dual energy X-ray absorptiometry scans at the lumbar spine and total body. Maternal 25(OH)D at recruitment (before 16 weeks gestation) was positively associated with the children's bone mineral content and density in boys, but not girls. In boys, a 10 nmol/L (4 ng/mL) increase in maternal 25(OH)D was associated with a median 0.5 g (95% CI 0.1,0.8) and 0.009 g/cm 2 (95% CI 0.001,0.017) increase in bone mineral content and density at the spine, respectively, and a median 0.006 g/cm 2 (95% CI 0.001,0.011) increase in at the total body. There was no sustained associations with 25(OH)D at the later timepoint (28-32 weeks) with any outcome. At age 11 years, maternal 25(OH)D levels during early pregnancy, but not late were positively associated with bone measures in boys, but not girls., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Evidence regarding the association between gestational vitamin D status and offspring body composition during childhood is inconsistent. Therefore, we aimed to determine the association between maternal vitamin D and offspring lean and fat mass in the Vitamin D in Pregnancy birth cohort., Methods: Subjects were mother-child pairs recruited from the Australian-based Vitamin D in Pregnancy cohort study. Mothers were recruited before 16 weeks' gestation and provided a blood sample at both recruitment and at 28-32 weeks' gestation. Serum vitamin D [25(OH)D] was measured by radioimmunoassay (Tyne and Wear, UK). Offspring lean and fat mass were quantified by using dual-energy X-ray absorptiometry (GE Lunar Prodigy, Madison, WI, USA) at 11 years of age., Results: Median maternal 25(OH)D levels were 55.9 (42.2-73.3) and 56.1 (43.6-73.9) at recruitment and 28-32 weeks' gestation, respectively. Maternal smoking was identified as an effect modifier in the association between maternal vitamin D status at recruitment and offspring body composition. In smokers, but not non-smokers, serum 25(OH)D status at recruitment was negatively associated with offspring fat mass percentage and positively associated with lean mass (both p < 0.05). There was no association with 25(OH)D status at 28-32 weeks' gestation., Conclusions: Maternal vitamin D status in early pregnancy, in smokers, is associated with offspring body composition. These important findings warrant confirmation in larger studies and trials., (© 2018 World Obesity Federation.)

Background/objectives: Cardiovascular disease (CVD) is a major cause of mortality and morbidity globally. Results from previous studies are inconsistent and it remains unclear whether low-serum 25 OHD levels are associated with an increased risk of CVD. These associations have been little studied in young women. The aim of this study was to assess the relationship between serum 25 OHD and obesity, body composition, metabolic profiles and blood pressure in young women., Subjects/methods: Women aged 16-25 years living in Victoria, Australia, were recruited through Facebook advertising in this cross-sectional study. Participants completed an online survey and attended a site visit in a fasted state, where parameters, including blood pressure, anthropometry, metabolic profiles, serum 25 OHD levels and body composition (using dual energy X-ray absorptiometry) were measured., Results: A total of 557 participants were recruited into this study. Multiple linear regression analysis showed that after adjusting for visceral fat, season, smoking, physical activity, age, alcohol intake, oral contraceptive use, country of birth, taking multivitamins and taking vitamin D supplement, a 10 nmol/L increase in 25 OHD levels was associated with 0.65% greater HDL levels (p = 0.016) and 0.92% greater triglyceride levels (p = 0.003). It was also associated with 0.48% lower BMI (p < 0.001), 0.50% lower total fat percentage (p < 0.001), 0.09% lower visceral fat percentage (p < 0.001), 0.14% lower visceral fat to total fat ratio (p < 0.001) and 0.36% lower trunk fat to total fat ratio (p < 0.001), after adjustment for season, smoking, physical activity, age, alcohol intake, oral contraceptive use, country of birth, taking multivitamins and taking vitamin D supplements. Although these associations were statistically significant, they were very small in magnitude and of uncertain clinical significance., Conclusions: These findings may help to explain an association between 25 OHD levels and CVD risk factors through associations with HDL, BMI, total body and visceral fat mass. Possible underlying mechanisms warrant further investigation.

Context: Vitamin D status and parathyroid hormone (PTH) levels influence the risk of accidental falls in older people, but the mechanisms underlying this effect remain unclear., Objective: Investigate the relationship between circulating PTH and 25 hydroxyvitamin D (25-OHD) levels and clinical tests of gait stability and balance as physical fall risk factors. We hypothesized that high levels of PTH and low 25-OHD levels would be significantly associated with gait stability and decreased balance performance., Design: Observational cohort study., Setting: Australian community., Participants: 119 healthy, ambulatory female twin adults aged 47-80 years residing in Victoria, Australia., Outcome Measures: Serum PTH and 25-OHD levels with clinical tests of gait stability [double support duration (DSD)] and dynamic balance (Step Test). Associations were investigated by regression analysis and by comparing groups divided by tertiles of PTH (<3.5, 3.5-4.9, >4.9pmol/L) and 25-OHD (<53, 53-75, >75 nmol/L) using analysis of variance., Results: Serum PTH was associated positively with DSD, with an increase of 10.6-15.7% when the mid and highest PTH tertiles were compared to the lowest tertile (p <0.025) when 25-OHD was included in the regression analysis. 25-OHD was significantly associated with DSD (greater by 10.6-11.1% when lowest and mid-tertiles compared with the highest 25-OHD tertile) (p <0.025) and dynamic balance (better performance by 12.6% in the highest compared with the lowest 25OHD tertile) (p <0.025)., Conclusion: These findings reveal an important new relationship between parathyroid hormone and gait stability parameters and add to understanding of the role of 25-OHD in motor control of gait and dynamic balance in community-dwelling women across a wide age span., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: While there is evidence linking vitamin D status with mood, this association and its clinical significance remain uncertain. Moreover, few studies have focused on young, community-dwelling females. The Safe-D study examined the association between serum 25-hydroxyvitamin D (25OHD) levels and mental health in young women., Methods: Participants completed an online questionnaire, wore a UV dosimeter to measure personal sun exposure and underwent a comprehensive health assessment. Serum 25OHD was measured by liquid chromatography-tandem mass spectrometry in 353 healthy women aged 16-25 years, living in Victoria, Australia. Mental health measures included: Patient Health Questionnaire (PHQ-9), 7-item Generalized Anxiety Disorder Scale (GAD-7), Kessler psychological distress scale (K10) and 12-item short-form health survey (SF-12), plus any self-reported mental disorder diagnoses or medication use., Results: The prevalence of self-reported mental disorder was 26% and of vitamin D deficiency 27%. The median (Q1, Q3) scores for the PHQ-9, GAD-7, K10 and SF-12 MCS were 6 (3, 9), 5 (2, 8), 19 (15, 25) and 43 (34, 49), respectively. Serum 25OHD levels were not associated with mental health scores. Vitamin D status was not associated with a reported diagnosis of depression or anxiety., Limitations: There was a low prevalence of severe vitamin D deficiency and mental health symptoms, which may reduce study power., Conclusion: Our findings do not support an association between serum 25OHD levels and mental health status in young women. Longitudinal studies and randomized clinical trials investigating vitamin D and mood in young women are needed to confirm and extend these results., (Copyright © 2016 Elsevier B.V. All rights reserved.)

No studies have explored the relationship with maternal vitamin D (25(OH)D) in pregnancy and offspring trabecular bone score (TBS). Our data suggest that maternal 25(OH)D in early pregnancy, but not late, may be associated with offspring TBS in boys. These data act as hypothesis-generating findings for confirmation in larger, longer-term studies., Introduction: Trabecular bone score (TBS), a novel tool derived from dual-energy X-ray absorptiometry (DXA), reflects the microarchitecture of the vertebrae. It has been shown to predict fracture independent of standard DXA parameters in adult populations. Previously, we demonstrated that maternal serum 25-hydroxyvitamin D (25(OH)D) during pregnancy is associated with offspring bone mineral content at age 11 years. However, associations with TBS have not been explored, thus we aimed to determine associations between maternal 25(OH)D and offspring TBS., Methods: Data were collected from the Vitamin D in Pregnancy (VIP) study. Venous blood samples were taken at recruitment and at 28-32 weeks' gestation. Maternal 25(OH)D was measured by radioimmunoassay. Offspring (n = 195, n = 181 with complete measures) underwent spine DXA (GE Lunar), at age 11 years (median = 10.9 (IQR 10.9-11.4)). TBS was calculated using TBS iNsight software., Results: Offspring of mothers with sufficient 25(OH)D levels (≥50 nmol/L) at recruitment had a higher TBS (1.363 vs. 1.340, p = 0.04). In multivariable linear regression models, after adjustment for child relative lean mass, sex and pubertal stage, a 10 nmol/L increase in maternal 25(OH)D was associated with a 0.005 (95% CI 0.000, 0.010, p = 0.04) increase in TBS. However when stratified by sex (p for interaction = 0.16), the association was significant in boys, but not girls. There were no associations with TBS and maternal 25(OH)D at 28-32 weeks., Conclusions: We speculate that maternal 25(OH)D in early pregnancy may be associated with TBS in offspring at age 11 in boys. These hypothesis-generating findings warrant confirmation with larger interventional and long-term follow-up studies.

The study aimed to explore determinants of bone parameters in young women. Most bone parameters were associated with height and lean mass. Bone parameters were not associated with vitamin D status. Future research should address whether interventions aimed at improving lean mass are beneficial to bone health in young women., Introduction: The implementation of prevention strategies during young adulthood may be crucial for osteoporosis prevention in later life, yet literature examining the determinants of bone health in premenopausal women is limited. We aimed to assess determinants of bone health, including serum 25-hydroxyvitamin D (25OHD), in females aged 16-25 years, living in Victoria, Australia, recruited through Facebook advertising., Methods: Serum 25OHD was measured by liquid chromatography-tandem mass spectrometry and bone health was measured using dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) in 326 participants., Results: Mean (± standard deviation) serum 25OHD was 69 ± 28 nmol/L and the prevalence of vitamin D deficiency (serum 25OHD <50 nmol/L) was 26%. Seven percent of participants (n = 23) reported taking a vitamin D supplement. Two percent of participants had low lumbar spine bone mineral density (Z-score <-2.0), 5% at the hip and 7% at the femoral neck. Serum 25OHD levels were not associated with DXA bone parameters, nor with pQCT bone parameters. Most bone parameters were positively associated with height and lean mass., Conclusion: Vitamin D status was not associated with bone health in young women in the current study. Our findings suggest that targeting other modifiable factors, such as lean body mass, is likely to be beneficial to bone health in young women. Longitudinal studies examining the association between vitamin D status and bone health in young women are necessary to confirm our findings. In addition, whether raising 25OHD levels is advantageous for young women's bone health is yet to be determined.

Vitamin D deficiency is a global public health concern. Studies of serum 25-hydroxyvitamin D (25(OH)D) determinants in young women are limited and few include objective covariates. Our aims were to define the prevalence of vitamin D deficiency and examine serum 25(OH)D correlates in an exploratory study of women aged 16-25 years. We studied 348 healthy females living in Victoria, Australia, recruited through Facebook. Data collected included serum 25(OH)D assayed by liquid chromatography-tandem MS, relevant serum biochemistry, soft tissue composition by dual-energy X-ray absorptiometry, skin melanin density, Fitzpatrick skin type, sun exposure using UV dosimeters and lifestyle factors. Mean serum 25(OH)D was 68 (sd 27) nmol/l and 26 % were vitamin D deficient (25(OH)D 2 h in the sun in summer daily, holidaying in the most recent summer period, serum Fe levels, height and multivitamin use were positively associated with 25(OH)D. Fat mass and a blood draw in any season except summer was inversely associated with 25(OH)D. Vitamin D deficiency is common in young women. Factors such as hormonal contraception, sun exposure and sun-related attitudes, as well as dietary supplement use are essential to consider when assessing vitamin D status. Further investigation into methods to safely optimise vitamin D status and to improve understanding of the impact of vitamin D status on long-term health outcomes is required.

Magnesium, phosphorus, zinc, calcium, potassium and protein all play integral roles in maintaining bone health in adults; however, less is known about the importance of these minerals in utero. We aimed to determine associations between maternal dietary consumption of these nutrients during gestation and birth measures in offspring. Of 475 pregnant women recruited from a single antenatal clinic before 16-week gestation (2002-2003) as part of the vitamin D in pregnancy study, 346 with recorded maternal dietary intakes at 28- to 32-week gestation and offspring measures at birth were included. At birth, trained personnel measured the infant's weight, knee-heel length, crown-heel length and head circumference. At age 11, returning offspring underwent assessment of bone mass by dual-energy X-ray absorptiometry (n = 171). Crown-heel length was positively and weakly correlated with maternal intakes of all measured nutrients except calcium, fat and carbohydrate (r = 0.15-0.17; all p ≤ 0.05). The associations with protein, phosphorus and potassium were not attenuated after adjustment for maternal and offspring characteristics. No sustained associations were seen with other birth measures. Further, associations with some nutrients persisted with offspring height at age 11 years. Offspring bone area was associated with maternal diet, but no other measure of bone mass at age 11. After adjustment for height, associations were not significant. These data highlight that whilst some nutritional factors during pregnancy are associated with offspring linear growth in utero and childhood, this does not necessarily translate into an effect on offspring bone measures in childhood.

Background: There is increasing evidence of the effect of maternal vitamin D intake during pregnancy on the risk of asthma and allergic outcomes in offspring. However, studies on the relationship between cord levels of 25-hydroxyvitamin D (25[OH]D) and asthma and allergic diseases are very few., Objective: Our aim was to investigate the associations between cord serum 25(OH)D levels and asthma, wheezing, allergic rhinitis, and atopic dermatitis in the offspring from birth to 5 years., Methods: Cord blood samples were collected at birth and analyzed for 25(OH)D levels in 239 newborns from the Etude des Déterminants pré et post natals du développement et de la santé de l'Enfant (EDEN) birth cohort. The children were followed up until age 5 years by using International Study of Asthma and Allergies in Childhood-based symptom questionnaires., Results: The median cord serum level of 25(OH)D was 17.8 ng/mL (interquartile range, 15.1 ng/mL). By using multivariable-adjusted logistic regression models, a significant inverse association was observed between cord serum 25(OH)D levels and risk of transient early wheezing and early- and late-onset atopic dermatitis, as well as atopic dermatitis, by the ages of 1, 2, 3, and 5 years. We found no association between cord serum 25(OH)D levels and asthma and allergic rhinitis at age 5 years., Conclusions: Cord serum 25(OH)D levels were inversely associated with the risk of transient early wheezing and atopic dermatitis by the age of 5 years, but no association was found with asthma and allergic rhinitis., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Context: Vitamin D deficiency has been implicated in the increased risk of several diseases. Exposure to air pollution has been suggested as a contributor to vitamin D deficiency. However, studies that have examined the effects of air pollution on vitamin D status are few and have never focused on prenatal life as an exposure window., Objective: Our aim was to investigate the associations between gestational exposure to urban air pollutants and 25-hydroxyvitamin D [25(OH)D] cord blood serum level in 375 mother-child pairs of the EDEN birth cohort., Design: The Atmospheric Dispersion Modelling System (ADMS-Urban) pollution model, a validated dispersion model combining data on traffic conditions, topography, meteorology, and background pollution, was used to assess the concentrations of two major urban pollutants, particulate matter less than 10 μm in diameter (PM(10)) and nitrogen dioxide (NO(2)), at the mother's home address during pregnancy. Cord blood samples were collected at birth and were analyzed for levels of 25(OH)D., Results: Maternal exposure to ambient urban levels of NO(2) and PM(10) during the whole pregnancy was a strong predictor of low vitamin D status in newborns. After adjustment, log-transformed 25(OH)D decreased by 0.15 U (P = 0.05) and 0.41 U (P = 0.04) for a 10-μg/m(3) increase in NO(2) and PM(10) pregnancy levels, respectively. The association was strongest for third-trimester exposures (P = 0.0003 and P = 0.004 for NO(2) and PM(10), respectively)., Conclusion: Gestational exposure to ambient urban air pollution, especially during late pregnancy, may contribute to lower vitamin D levels in offspring. This could affect the child's risk of developing diseases later in life.

Background/objectives: We tested the hypothesis that the relationship between maternal 25-hydroxyvitamin D (25-(OH)D) and offspring birth size differs according to offspring vitamin D receptor (VDR) genotype (Apa1, Bsm1, Fok1 or Taq1)., Subjects/methods: Mothers of 354 singleton babies had serum 25-(OH)D concentration measured at 28-30 weeks of gestation and consented to measurement of their babies soon after birth. DNA was extracted from the babies' Guthrie cards., Results: There was evidence of effect modification by infant FokI genotype. Babies of deficient mothers had lower birth weight with FF or Ff, but not ff genotype (P-value for interaction after adjustment for potential confounding factors=0.02), but thicker subscapular and suprailiac skinfolds with ff, but not FF or Ff genotype (P=0.008 and 0.02, respectively). Sample size was insufficient to investigate effect modification by the other VDR polymorphisms., Conclusions: These preliminary findings suggest that studies of maternal vitamin D status and birth size may need to take VDR genotype into account.

Objective: A high prevalence of mild to moderate vitamin D deficiency has been observed in women who have recently arrived from the horn of Africa and living in inner Melbourne. Vitamin D status of women with differ-ing age and ethnic distributions residing in other suburbs is unknown., Method: A tertiary referral Women's hospital-based survey of serum 25(OH)D concentrations in 2,690 women aged 14-78 years residing in Mel-bourne between 1 July 2004 and 30 June 2005. We computed odds of serum 25(OH)D concentrations<50 nmol/L and used tests of homogeneity across different suburbs in Melbourne, Victoria., Results: Women with moderate vitamin D deficiency from all suburbs were young [29.1+/-7.2 years (mean+/-standard deviation)]. The odds of moderate vitamin D deficiency were highest in inner suburbs and Greenvale, Coburg, Pascoe Vale South, Fawkner, Broadmeadows and Campbellfield from the Hume-Moreland municipality (p value for homogeneity of odds<0.001)., Conclusion: Vitamin D deficiency ap-pears to be a growing health concern in Australia and may be more prevalent in younger women in Victoria than anticipated.

Objectives: To determine the prevalence of vitamin D deficiency in older people in residential care and the influence that the level of vitamin D may have on their incidence of falls., Design: Prospective cohort., Setting: Residential care facilities for older people in several states of Australia., Participants: Six hundred sixty-seven women in low-level care and 952 women in high-level care, mean age 83.7 years., Measurements: Serum 25-hydroxyvitamin D (25D) levels and recognized risk factors for falls including current medication use, a history of previous fractures, weight, tibial length (as a surrogate for height), cognitive function, walking ability, and frequency of going outdoors were determined. The women in low-level care and high-level care were followed for an average of 145 and 168 days, respectively. Falls were recorded prospectively in diaries completed monthly by residential care staff., Results: Vitamin D deficiency (defined as a serum 25D level below 25 nmol/L) was present in 144 (22%) women in low-level care and 428 (45%) in high-level care. After excluding 358 bed-bound residents and adjusting for weight, cognitive status, psychotropic drug use, previous Colles fracture, and the presence of wandering behavior, log serum 25D level remained independently associated with time to first fall. The adjusted hazards ratio was 0.74 (95% confidence interval=0.59-0.94; P=.01), implying a 20% reduction in the risk of falling with a doubling of the vitamin D level., Conclusion: Vitamin D deficiency is common in residential care in Australia. A low level of serum vitamin D is an independent predictor of incident falls.

The review provides an evaluation of the therapeutic potential of vitamin D analogues in the context of the current understanding of vitamin D biochemistry, molecular biology and physiology. Vitamin D activity results from several circulating and intracellular physiological metabolites acting simultaneously through at least three receptors. Common analogues are reviewed. Although most vitamin D analogues have traditionally been analogues of 1,25-dihydroxyvitamin D, it may be better to deliver high doses of base vitamin or (analogues) of 25-hydroxyvitamin D. This would permit physiological endocrine, paracrine and autocrine vitamin D metabolism. Agonists or antagonists of tissue-specific vitamin D metabolic pathways could be coadministered. The importance of measuring endogenous vitamin D metabolites during in vivo studies and the pitfalls of extending data across species and time are emphasised. Human vitamin D analogue trials should include direct comparison against the related endogenous metabolite.

Residents from high level (nursing homes) and low-level care facilities (hostel) being served the three common diet texture modifications (full diet, soft-minced diet and pureed diet) were assessed. Individual plate waste was estimated at three meals on one day. Fifty-six males and 156 females, mean age 82.9+/-9.5 (SD) years, of which 139 lived in nursing homes (NH) and 76 in hostels (H) were included. Mean total energy served from meals was 5.3 MJ/day, 5.1 to 5.6 MJ/day, 95% confidence intervals (CI), in NH which was less than in H, 5.9 MJ/day (CI 5.6 to 6.2 MJ/day) (P=0.007). Protein and calcium intakes were lower in NH, 44.5g (CI 41.5 to 47.5g), 359.0mg (CI 333.2 to 384.8mg), versus 50.5g (CI 46.6 to 54.3g), 480.5mg (CI 444.3 to 516.7mg) in H (P=0.017, P<0.001 respectively). There was no difference in nutrient/energy ratios, except for protein/energy, which was higher in NH 11.7 (CI 11.3 to 12.2) than in H 9.8 (CI 9.4 to 10.3) (P<0.001). Ability to self-feed had no significant effect on nutrient intakes in NH. The self fed group (N=63) had the following nutrient intakes: energy 4.0 MJ (CI 3.6 to 4.3 MJ), protein 44.6g (CI 40.3 to 48.9g), calcium 356.9mg (CI 316.3 to 397.4mg), fibre 14.9g (CI 13.2 to 16.5g). The assisted group (N=64) had the following nutrient intakes: energy 3.9MJ (CI 3.6 to 4.2MJ), protein 46.0g (CI 40.7 to 49.6), calcium 361.9mg (CI 327.8 to 396.1mg), fibre 14.9g (CI 13.2 to 16.1g). Of NH classified as eating impaired, 36% received no assistance with feeding and had lower intakes of protein 37.8g (CI 33.0 to 42.1g) compared to those receiving some assistance 46.1g (CI 41.3 to 50.9g) (P=0.026). Reduced energy intake accounted for the differences in nutrient intakes between nursing homes and hostels, except for protein. Strategies to effectively monitor nutrient intakes and to identify those with eating impairment are required in order to ensure adequate nutrition of residents in nursing homes and hostels.

Objectives: To determine whether falling relates to serum levels of vitamin D and parathyroid hormone., Design: A cross-sectional study with retrospective analysis., Setting: An aged-care institution in Melbourne Australia., Participants: Ambulant nursing home and hostel residents (n = 83)., Measurements: Frequency of falling, frequency of going outdoors, use of cane or walker, age, sex, weight, type of accommodation, and duration of residence. Serum concentrations of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and parathyroid hormone (PTH). Plasma concentrations of albumin, calcium, phosphate, and creatinine. Use of furosemide or non-benzodiazepine anticonvulsants., Results: Median age of residents was 84 years. The cohort was vitamin D deficient with a median (interquartile range) 25-hydroxyvitamin D level of 27 (18-37) nmol/L (one-third the reference range median), P < .001. The median (interquartile range) PTH of 5.2 (3.8-7.7) pmol/L exceeded the reference range median, P < .001. Residents who fell (n = 33) had lower serum 25-hydroxyvitamin D levels than other residents (medians 22 vs 29 nmol/L, P = .02) and higher serum PTH levels (medians 6.2 vs 4.8 pmol/L, P < .01). Sixty residents lived in the hostel (72%), and 41 (49%) walked without any walking aid. In a multiple logistic regression for falling, higher serum PTH remained independently associated with falling, with an odds ratio (95% confidence interval) for falling of 5.6 (1.7-18.5) per unit of the natural logarithm of serum PTH. Other terms in the regression were hostel accommodation, odds ratio .04 (.01-.25), and ability to walk without aids, odds ratio .07 (.01-.37)., Conclusions: In ambulant nursing home and hostel residents, residents who fall have lower serum 25-hydroxyvitamin D and higher serum parathyroid hormone levels than other residents. The association between falling and serum PTH persists after adjustment for other variables.

Using a commercial kit method we obtained a vitamin D metabolite level within the normal range in a patient with biopsy-proven osteomalacia. This suggested that the ethanol extraction method employed had not removed serum factors known to falsely elevate the measurement of vitamin D metabolites. We therefore compared the levels measured after ethanol extraction and after purification by chromatography on Sep-pak C18 or Sephadex LH-20. Vitamin D metabolite levels after ethanol extraction of sera correlated with, but were higher than, those after chromatography on Sep-pak C18 cartridges (r = 0.84; 134 +/- 76 vs 76 +/- 46 nmol/l: mean +/- SD; p less than 0.01). Results were similar after chromatography on Sep-pak C18 and Sephadex LH-20 (r = 0.95; 79 +/- 46 vs 68 +/- 41 nmol/l). Sera from 5 patients (4 with osteomalacia, 1 with chronic pancreatitis/malabsorption) had vitamin D metabolite levels in the normal range after ethanol extraction but had low levels after Sep-pak C18 chromatography; four of these sera also had low levels after chromatography on Sephadex LH-20. These findings indicate that chromatography of serum on Sep-pak C18 cartridges corrects falsely elevated vitamin D metabolite levels measured by protein binding assay.