Mark S. Stein

Should older people in residential care receive vitamin D to prevent falls? Results of a randomized trial.

Objectives: To determine whether vitamin D supplementation can reduce the incidence of falls and fractures in older people in residential care who are not classically vitamin D deficient.

Serum vitamin D and falls in older women in residential care in Australia

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.

Falls Relate to Vitamin D and Parathyroid Hormone in an Australian Nursing Home and Hostel

OBJECTIVES: To determine whether falling relates to serum levels of vitamin D and parathyroid hormone.

Prevalence and risk factors for osteopenia in dialysis patients

Dialysis patients are at risk for low bone mineral density (BMD) consequent of hyperparathyroidism, 1,25-dihydroxyvitamin D deficiency, previous immunosuppression, chronic acidosis, secondary amenorrhea, and chronic heparin and aluminum exposure. We wanted to determine the prevalence and distribution of osteopenia and the influence of risk factors for osteopenia in dialysis patients. Dual energy x-ray absorptiometry was used to record BMD at the lumbar spine (LS), hip, and nondominant forearm. Results were expressed as Z-scores (standard deviations from the mean of a healthy age- and gender-matched reference population). Osteopenia was defined as a Z-score worse than -2. In the 250 dialysis patients studied, the prevalence of osteopenia at the LS, femoral neck (FN) and ultradistal radius (UD) was 8%, 13% and 20%, respectively. The median Z-scores at these sites were all significantly different from the healthy reference population median of 0 and were 0.29 (P = 0.008), -0.67 (P < 0.001), and -1.01 (P < 0.001), respectively. Previous transplantation was associated with as much as a one Z-score lower BMD at the FN (P = 0.0069) and UD (P = 0.0011) and a marginally significant reduction at the LS (P = 0.0777). Previous parathyroidectomy was associated with a markedly higher LS BMD (P = 0.0001) and a higher BMD at the FN (P = 0.0017) but not the UD (P = 0.3691). A history of secondary amenorrhea was associated with a lower FN BMD (P = 0.0047) but not a significantly lower BMD at the LS (P = 0.0978) or UD (P = 0.2327). In hemodialysis patients without a history of transplantation, parathyroidectomy, or secondary amenorrhea, there was no correlation between Z-score at any site and duration of dialysis. Thus, osteopenia in dialysis patients occurs in both axial and appendicular sites and sites of compact and cancellous bone. It is more common with previous transplantation and secondary amenorrhea, whereas a history of parathyroidectomy is associated with increased BMD. No relationship was found between BMD and duration of hemodialysis, which suggests that important changes in BMD occur during the predialysis stage of chronic renal failure.

Risk factors for secondary hyperparathyroidism in a nursing home population

OBJECTIVE Secondary hyperparathyroidism may cause bone loss and structural deterioration of bone and may thus be a cause of fracture in the elderly. Vitamin D deficiency, renal impairment and medications are potential causes of hyperparathyroidism and may also directly predispose to fracture. We present the first findings of an ongoing study of hip fracture, vitamin D deficiency and hyperparathyroidism in a large Australian nursing home.

Relationships with serum parathyroid hormone in old institutionalized subjects

OBJECTIVE and BACKGROUND Old people in residential care are at the highest risk of any group for hip fracture. This may relate to their high prevalence of hyperparathyroidism. There are few data, however, on relationships with serum parathyroid hormone (PTH) in these individuals. This study therefore examined complex associations with serum PTH in nursing home and hostel residents.

An update on the therapeutic potential of vitamin D analogues

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.

Determination of age at death using combined morphology and histology of the femur.

Bone is characterised by age‐related morphological and histological changes. We have previously established an automated method of recording bone morphometry and histology from entire transverse sections of cortical bone. Our aim was to determine whether data acquired using this automated system were useful in the prediction of age. Ninety‐six specimens of human femoral middiaphysis were studied from subjects aged 21–92 y. Equations predicting specimen age were constructed using macroscopic data (total subperiosteal area (TSPA), periosteal perimeter (PP), endosteal perimeter (EP), cortical bone area (CA) and moments of area) and microscopic data (the number, size and diversity of pores and intracortical porosity) together with sex, height and weight. Both TSPA and PP were independent predictors of age but the number of pores was not a significant predictor of age in any equation. The age predicted by these equations was inaccurate by more than 8 y in over half the subjects. We conclude that we could not predict age at a clinically acceptable level using data from our automated system. This most likely reflects an insensitivity to regional age‐related changes in bone histology because we recorded data from each entire cortex. Automated bone measurement according to cortical region might be more useful in the prediction of age. The inclusion of TSPA together with PP as independent predictors of age raises the possibility that a future measure of periosteal shape at the femoral diaphysis could also be helpful in the prediction of age. The accuracy reached with the relatively simple methods described here is sufficient to encourage the development of image‐analysis systems for the automatic detection of more complex features.

Diffusion tensor imaging of acute inflammatory lesion evolution in multiple sclerosis

The initiating events in multiple sclerosis (MS) plaque formation are poorly understood. Retrospective analysis of serial imaging data can improve the understanding of tissue changes characterising acute MS lesion evolution. This study aimed to assess lesion evolution using diffusion tensor imaging data from serially acquired scans from 22 patients with MS. Mean diffusivity (MD) and fractional anisotropy (FA) were measured from 13 suitable plaques from five patients and carefully matched regions of contralateral normal-appearing white matter. Measurement times were on average: 5 months and 1 month prior to, during, and 1 month and 2 months post gadolinium-enhancement. A significant increase in MD (7.25%) but no change in FA was observed in white matter areas that exhibited enhancement 5 months later. The pre-lesional MD increase was significantly correlated with the MD increase 2 months subsequent to enhancement (R=0.73, p=0.04) but not to the MD increase during enhancement (R=0.11). These results suggest that MD is sensitive to tissue changes that precede blood-brain barrier (BBB) breakdown by at least 5 months and that MD assessments may predict injury following BBB restoration.

A multidisciplinary practice guideline for hip fracture prevention in residential aged care

High numbers of hip fractures in residential aged care make the institution of a practical prevention program an urgent priority. We developed and implemented a pilot multidisciplinary practice guideline integrating fall prevention, hip protectors, and osteoporosis management in a group of 50 residents at very high risk of hip fracture. We describe the characteristics of these residents and report the outcome of this observational study, which resulted in an implementation rate of between 50% and 86% for six individually considered interventions at 6‐month follow‐up.