Serum 25-OHD insufficiency as a risk factor for hip fracture

The aging population and an increasing number of hip fractures worldwide have made prevention of hip fractures a matter of importance. The prevalence of hypovitaminosis D in patients with acute hip fracture has been reported widely in recent years, and the vitamin D nutritional status in such reports is usually evaluated based on serum 25-hydroxyvitamin D (25-OHD). The aim of this article is to review the relationship of serum 25-OHD and osteoporotic fracture and the prevalence of 25-OHD insufficiency in patients with hip fracture, including assessment of nutritional status, oral status, activity, and dementia. We conclude that the serum 25-OHD level may be a useful index for risk of hip fracture in elderly people.     

Hip fracture patients in India have vitamin D deficiency and secondary hyperparathyroidism

Summary

This study evaluated the parameters of bone mineral homeostasis including 25(OH)D and PTH in 90 Indian patients with hip fracture and 90 controls. Hypovitaminosis D, secondary hyperparathyroidism, and biochemical osteomalacia was present in 77, 69, and 50 % patients, respectively, significantly higher compared to controls. Vitamin D deficiency is an important risk factor for hip fracture.

Introduction

The prevalence of vitamin D deficiency is not well known in hip fracture patients from India. Therefore, the present study was conducted to evaluate the parameters of bone mineral homeostasis including 25(OH)D and intact PTH in hip fracture from North India.

Methods

Ninety consecutive patients with hip fracture and similar number of age- and sex-matched controls were enrolled in the study. The fasting venous samples were analyzed for 25-hydroxyvitamin D (25-OHD), intact parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium, and phosphorus. Vitamin D deficiency was defined as serum 25-OHD of <20 ng/dl.

Results

The mean age of hip fracture subjects was 65.9?±?12.6 which was comparable in men and women. Majority of study subjects were women (70 women and 20 men). The serum 25(OH)D and calcium levels were significantly lower, whereas the intact PTH and ALP levels were significantly higher in patients compared to controls. There was significant negative correlation between serum 25(OH)D and PTH. In the hip fracture group, 76.7 % of the subjects had vitamin D deficiency, and 68.9 % had secondary hyperparathyroidism. In the control group, vitamin D deficiency and elevated PTH levels were seen in 32.3 and 42.2 %, respectively.

Conclusion

About three fourths of hip fracture patients have vitamin D deficiency, and two thirds have secondary hyperparathyroidism. Therefore, the serum 25-OHD level may be a useful index for the assessment of risk of hip fracture in India.     

Vitamin D status among patients with hip fracture and elderly control subjects in Yekaterinburg, Russia

Purpose Vitamin D deficiency leads to secondary hyperparathyroidism and osteomalacia, and both conditions are associated with fractures, the most severe being hip fracture. The serum 25-hydroxyvitamin D level depends on latitude and season. Yekaterinburg is situated at a high latitude and the duration of winter is about 5 months. Methods In this study, the serum 25(OH)D and PTH concentrations, and the prevalence of hypovitaminosis D in elderly people, inhabitants of Yekaterinburg, were investigated. The study was performed on 63 people with hip fracture (mean age, 68.8 years) and 97 independently living elderly people (mean age, 70.2 years). Results Serum 25(OH)D (mean±SD) in the hip fracture group was 22.4±11.4 nmol/L, significantly lower than in control group, which was 28.1±10.1 nmol/L. The percentage of patients with severe hypovitaminosis D (<25 nmol/L) in the hip fracture group was 65%, compared to 47% in the control group (p<0.05). The prevalence of hypovitaminosis D among hip fracture patients, as well as among independently living elderly people in Yekaterinburg, was high. Conclusion Supplementation of vitamin D in elderly people with and without fracture might prevent secondary hyperparathyroidism, osteomalacia and fractures.     

Changes in Bone and Calcium Metabolism Following Hip Fracture in Elderly Patients

Although hip fracture is one of the most common causes of acute immobilization in elderly patients, little is known about the influence of immobilization on changes in bone and calcium metabolism following this event. We therefore compared serum biochemical indices of bone and calcium metabolism in 20 elderly subjects with hip fracture with those measured in 20 healthy age-matched controls. Rankin scores, a measure of functional dependence with 0 representing independence and 5 representing total dependence, were assigned. We also examined serial changes in these biochemical indices from shortly following the fracture to the early recovery period. Ionized calcium, intact parathyroid hormone (PTH), intact bone Gla protein (BGP), pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), 25-hydroxyvitamin D (25-OHD), and 1,25-dihydroxyvitamin D (1,25-[OH]₂D) were measured. One week after the fracture, mean serum concentrations of calcium and ICTP were elevated in correspondence to degree of immobilization (mean Rankin score; 4.4), while serum concentrations of BGP, PTH, 25-OHD, and 1,25-[OH]₂D were depressed. Rankin score (mean: 4.4) correlated positively with ICTP and negatively with BGP at this time. At 2 months, calcium and ICTP elevation decreased and BGP, PTH and 1,25-[OH]₂D were less depressed, coinciding with a decline in Rankin score from 4.2 to 2.2. Indices were further improved at 3 months (mean Rankin score, 1.3), with calcium and BGP returning to normal. We concluded that increased bone resorption, and decreased bone formation, and hypercalcemia are present by 1 week following the hip fracture, and some resorption increase persists for at least 3 months. These changes could explain in part the high risk of another hip fracture. Received: 3 April 2000 / Accepted: 15 December 2000     

Glomerular Filtration Rate Is a Major Determinant of the Relationship between 25-Hydroxyvitamin D and Parathyroid Hormone

The reference range for 25-hydroxyvitamin D (25-OHD) remains uncertain, and it is not clear as to whether interpretation of circulating 25-OHD would be aided by simultaneous measurement of serum parathyroid hormone (PTH). We wanted to define the level of serum 25-OHD associated with a raised serum PTH and to examine the determinants of the relationship between serum 25-OHD and serum PTH concentration. We retrospectively examined data for patients who had a 25-OHD measurement and other biochemical variables over a 12-month period in our center. We found that 28% of patients had a serum 25-OHD level below 50 nmol/L and serum PTH level in the normal reference range, whereas 24% had a serum 25-OHD level below 50 nmol/L with a serum PTH value above the normal reference range. At a serum 25-OHD level of 80 nmol/L, 1.5% had an elevated serum PTH and, at 50 nmol/L, 8% had raised serum PTH. Further examination showed that for patients with low serum 25-OHD, low glomerular filtration rate (GFR) was a major determinant of the PTH response. These data confirm an inverse correlation between serum 25-OHD and serum PTH. Minimal numbers of patients (1.5% of the study group) have a raised serum PTH at a serum 25-OHD level of 80 nmol/L. GFR is a major determinant of the PTH response to decreasing serum levels of 25-OHD.     

Risk factors for clinical stress fractures in male military recruits: a prospective cohort study

This prospective study was aimed at evaluating risk factors for symptomatic stress fractures among 179 Finnish male military recruits, aged 18 to 20 years. The subjects were studied in the very beginning of the military service of 6 to 12 months in summer. Bone mineral content (BMC) and density (BMD) were measured by dual energy X-ray absorptiometry (DXA) at the lumbar spine and at the hip and heel ultrasound investigation was performed. Blood was sampled for determination of serum total and free testosterone, total and free estradiol, sex hormone-binding globulin (SHBG), procollagen type I N propeptide, total and carboxylated osteocalcin, tartrate-resistant acid phosphatase 5b, 25-hydroxyvitamin D (25-OHD), and intact parathyroid hormone (iPTH), as well as for studying the XbaI and PvuII polymorphisms of the estrogen receptor gene and the CAG repeat polymorphism of the androgen receptor gene. Urine was collected for the determination of N-terminal cross-linking telopeptide of type I collagen. Muscle strength was measured and Cooper's test was performed. Current exercise, smoking, calcium intake, and alcohol consumption were recorded using a questionnaire. During military service, 15 men experienced a stress fracture, diagnosed with X-ray in 14 and with nuclear magnetic resonance in one man. Those who experienced a fracture were taller than those who did not (P = 0.047). The result of Cooper's test was worse in the fracture group than in the non-fracture group (P = 0.026). Femoral neck and total hip BMC and BMD, adjusted for age, weight, height, exercise, smoking, and alcohol and calcium intake were lower (P = 0.021-0.041) for the fracture group. Stress fractures associated with higher iPTH levels (P = 0.022) but not with lower 25-OHD levels. Bone turnover markers as well as sex hormone and SHBG levels were similar for men with and without stress fracture. There was no difference in the genetic analyses between the groups. In conclusion, tall height, poor physical conditioning, low hip BMC and BMD, as well as high serum PTH level are risk factors for stress fractures in male Finnish military recruits. Given the poor vitamin D status of young Finnish men, intervention studies of vitamin D supplementation to lower serum PTH levels and to possibly reduce the incidence of stress fractures are warranted.     

High prevalence of vitamin D deficiency and reduced bone mass in elderly women with Alzheimer’s disease

Patients with Alzheimer’s disease (AD) are at increased risk for falls and hip fractures. To better understand causes and prevention, we measured bone mineral density (BMD) in the second metacarpals of 46 ambulatory elderly women with AD and analyzed its relation to serum biochemical indices, sunlight exposure, and vitamin D intake. BMD was significantly less than in age-matched controls. In 26% of AD patients, the serum 25-hydroxyvitamin D (25-OHD) concentration was at a deficient level (5–10 ng/mL), and in 54% it was at an osteomalacic level (<5 ng/mL). Concentrations of ionized calcium were significantly lower in patients. Conversely, concentrations of serum bone Gla-protein and urinary hydroxyproline in patients were significantly higher than in controls. BMD correlated positively with 25-OHD concentration (p = 0.0041) and negatively with parathyroid hormone (PTH) concentration (p = 0.0022). PTH was higher in patients than in controls, and correlated negatively with 25-OHD (p < 0.0001). Many AD patients were sunlight-deprived and consumed less than 100 IU of vitamin D per day. We concluded that vitamin D deficiency due to sunlight deprivation and malnutrition, together with compensatory hyperparathyroidism, contributes significantly to reduced BMD in AD patients. Low BMD increases risk of hip fractures in patients with AD, but may be improved by vitamin D supplementation.     

Hypovitaminosis D in patients with osteoporotic hip fractures

BackgroundInadequate serum vitamin D levels are associated with secondary hyperparathyroidism, increased bone turnover, bone loss and increased fracture risk. Vitamin D is well recognized to be suboptimal in older patients when compared to age-matched controls. There are no published studies on the prevalence of hypovitaminosis D in Indian population with fragility fractures around the hip associated with osteoporosis and comminution at the fracture site.AimTo investigate the prevalence of hypovitaminosis D in patients admitted with osteoporotic hip fractures and associated fracture site comminution in a South Indian Institute.Material & MethodsA prospective cross sectional study was conducted on 100 patients admitted with osteoporotic hip fracture. Measurement of serum 25-hydroxy vitamin D was done and the same was correlated with the degree of osteoporosis using Singh’s index and fracture site comminution.ResultsOut of 100 patients studied, 92% had hypovitaminosis D with mean vitamin D level of 16.08 ± 5.95 ng/dl (65% vitamin D deficiency with mean 13.16 ± 4.24 ng/dl and 27% vitamin D insufficiency with mean 23.11 ± 2.62 ng/dl) and 94% had osteoporosis with Singh’s index grade 3 or less. Out of the 36 patients with fracture site comminution 34 patients (94%) had hypovitaminosis D and 33 patients (91.6%) had osteoporosis. Statistical significance was established for all the variables.ConclusionSignificant association was found between hypovitaminosis D, osteoporosis and fracture site comminution. High prevalence of hypovitaminosis D in patients presenting with hip fractures and fracture site comminution implicates the necessity for proper evaluation and effective supplementation of vitamin D in elderly patients along with anti-osteoporotic regimens for effective prevention and appropriate management of osteoporotic hip fractures.     

High prevalence of hypovitaminosis D in pregnant Japanese women with threatened premature delivery

Serum 25-hydroxyvitamin D (25-OHD) concentrations are thought to accurately reflect vitamin D stores, and vitamin D deficiency causes secondary hyperparathyroidism, irreversible bone loss, and increased risk of fracture. Recent studies suggest that decrease of serum 25-OHD level in mothers could increase the risk of preeclampsia, cesarean section, and craniotabes. Furthermore, this deficiency may affect bone mass and the incidence of neuromuscular diseases of their children in the future. In the present study, the serum concentration of 25-OHD in 93 pregnant women after the 30th week of their gestation was determined by direct radioimmunoassay. Mean 25-OHD levels in spring, summer, fall, and winter were 14.3 ± 5.1, 15.7 ± 6.4, 13.7 ± 5.1, and 13.9 ± 4.2 ng/ml, respectively. Severe vitamin D deficiency (25-OHD < 10 ng/ml) was found in 10 of these 93 women. Overall, hypovitaminosis D, which was defined as serum 25-OHD concentration equal to or less than 20 ng/ml, was revealed in 85 mothers (89.5%). Serum 25-OHD levels were not associated with either intact parathyroid hormone or corrected calcium concentrations, but were negatively associated with serum type I collagen N-terminal telopeptide and bone-specific alkaline phosphatase in these subjects. Mothers with threatened premature delivery had significantly lower 25-OHD levels (11.2 ± 3.2 ng/ml) than those in mothers with normal delivery (15.6 ± 5.1 ng/ml). In conclusion, the present data suggest a high prevalence of hypovitaminosis D in perinatal pregnant Japanese women throughout the year, which seems to affect bone metabolism and to be associated with threatened premature delivery.     

25-hydroxyvitamin D levels and bone histomorphometry in hemodialysis renal osteodystrophy

BACKGROUND: The importance of 25-hydroxyvitamin D (25-OHD) serum levels in hemodialysis chronic renal failure has not been so far histologically evaluated. Information still lacking relate to the effect of 25-OHD deficiency on serum parathyroid hormone (PTH) levels and on bone and its relationship with calcitriol levels. METHODS: This retrospective study has been performed on a cohort of 104 patients on hemodialysis from more than 12 months, subjected to transiliac bone biopsy for histologic, histomorphometric, and histodynamic evaluation. The patients, 61 males and 43 females, mean age 52.9 +/- 11.7 years, hemodialysis length 97.4 +/- 61.4 months, were treated with standard hemodialysis and did not receive any vitamin D supplementation. Treatment with calcitriol was not underway at the time of the biopsy. Transiliac bone biopsies were performed after double tetracycline labels. In addition, serum intact PTH (iPTH), alkaline phosphatase, and 25-OHD were measured. Calcitriol serum levels was also measured in a subset of patients (N= 53). The patients were divided according to serum 25-OHD levels in three groups: (1) 0 to 15 (15 patients), (2) 15 to 30 (38 patients), and (3) >30 ng/mL (51 patients). RESULTS: There was no significant difference in average age, hemodialysis age, serum PTH [490 +/- 494, 670 +/- 627, and 489 +/- 436 pg/mL, respectively (mean +/- SD)], alkaline phosphatase, and calcitriol between the three groups. The parameters double-labeled surface, trabecular mineralizing surface, and bone formation rate were significantly lower in group 1 than in the other groups (P < 0.03, < 0.03, and < 0.02, respectively). Osteoblast surface and adjusted apposition rate were borderline significantly lower in group 1 (P < 0.06 and < 0.10). There was no statistical difference in the biochemical and bone parameters between groups 2 and 3. A positive significant correlation was found between several bone static and dynamic parameters and 25-OHD levels in the range 0 to 30 ng/mL, showing a vitamin D dependence of bone turnover at these serum levels. However, actual evidence of an effect on bone of 25-OHD deficiency was found at serum levels below 20 ng/mL. With increasing 25-OHD levels beyond 40 ng/mL, a downslope of parameters of bone turnover was also observed. CONCLUSION: Since PTH serum levels are equally elevated in low and high 25-OHD patients, while calcitriol levels are constantly low, an effect of 25-OHD deficiency (group 1) on bone, consisting of a mineralization and bone formation defect, can be hypothesized. The effect of vitamin D deficiency or bone turnover is found below 20 ng/mL. The optimal level of 25-OHD appears to be in the order of 20 to 40 ng/mL. Levels of the D metabolite higher than 40 ng/mL are accompanied by a reduction of bone turnover.     

The relationship between vitamin D and parathyroid hormone: calcium homeostasis, bone turnover, and bone mineral density in postmenopausal women with established osteoporosis

It is evident from several studies that not all patients with hypovitaminosis D develop secondary hyperparathyroidism. What this means for bone biochemistry and bone mineral density (BMD) remains unclear. The aim of this study was to investigate the effects of hypovitaminosis D (defined as a 25OHD < or = 30 nmol/l) and patients with a blunted PTH response (defined arbitrarily as a PTH within the standard laboratory reference range in the presence of a 25OHD < or = 30 nmol/l) in comparison to patients with hypovitaminosis D and secondary hyperparathyroidism (defined arbitrarily as a PTH above the standard laboratory reference range in the presence of a 25OHD < or = 30 nmol/l) and vitamin D-replete subjects (25OHD > 30 nmol/l). Four hundred twenty-one postmenopausal women (mean age: 71.2 years) with established vertebral osteoporosis were evaluated by assessing mean serum calcium, 25OHD, 1,25(OH)2D, bone turnover markers, and BMD. The prevalence of hypovitaminosis D was 39%. Secondary hyperparathyroidism was found in only one-third of these patients who maintained calcium homeostasis at the expense of increased bone turnover relative to the vitamin D-replete subjects (bone ALP mean difference: 43.9 IU/l [95% CI: 24.8, 59.1], osteocalcin: 1.3 ng/ml [95% CI: 1.1, 2.5], free deoxypyridinoline mean difference: 2.6 nmol/nmol creatinine [95% CI: 2.5, 4.8]) and bone loss (total hip BMD mean difference: 0.11 g/cm2 [95% CI: 0.09, 0.12]). Patients with hypovitaminosis D and a blunted PTH response were characterized by a lower serum calcium (mean difference: 0.07 mmol/l [95% CI: 0.08, 0.2]), a reduction in bone turnover (bone ALP mean difference: 42.4 IU/l [95% CI: 27.8, 61.9], osteocalcin: 1.6 ng/ml [95% CI: 0.3, 3.1], free-deoxypyridinoline mean difference: 3.0 nmol/nmol creatinine [95% CI: 1.9, 5.9]), but protection in bone density (total hip BMD mean difference: 0.10 g/cm2, [95% CI: 0.08, 0.11]) as compared to those with hypovitaminosis D and secondary hyperparathyroidism. This study identifies a distinct group of patients with hypovitaminosis D and a blunted PTH response who show a disruption in calcium homeostasis but protected against PTH-mediated bone loss. This has clinical implications with respect to disease definition and may be important in deciding the optimal replacement therapy in patients with hypovitaminosis D but a blunted PTH response.     

Vitamin D status and bone mass in UK South Asian women

INTRODUCTION: Low vitamin D status is prevalent among South Asians living in the UK. The relationship, however, between serum 25-hydroxyvitamin D level (25OHD), serum parathyroid level (PTH) and bone mass in this group of women is unknown. The aim of this study was to determine the association between serum PTH, 25OHD and bone mass in a population based sample of young UK South Asian women. MATERIALS AND METHODS: Names of South Asian women aged 18 to 36 years of Pakistani origin living in the Greater Manchester area were identified from primary care registers using validated computer software. Subjects were invited to attend for (i) a blood test for assessment of serum calcium (Ca), albumin, PTH and 25OHD and (ii) for bone mineral density (BMD) scanning using the following: areal BMD at the hip (femoral neck, total hip) and lumbar spine using dual X-ray absorptiometry (Hologic QDR 4500), and volumetric BMD at the distal radius using peripheral quantitative computed tomography (Norland Stratec XCT 2000). Linear regression was used to determine the association between serum 25OHD, PTH and BMD at the different sites with adjustments made for age. RESULTS: In all, 78 women (mean age 29.2 years) were included in the analysis. Mean serum Ca level was 2.42 mmol/l, 25OHD, 7.9 ng/ml and PTH, 52.8 pg/ml. The majority of women (94%) had serum 25OHD levels 15 ng/ml, though rose progressively in subjects with levels below 10 ng/ml. Serum 25OHD was positively associated with BMD at the hip and spine while PTH was negatively associated with BMD at the hip and spine. When categorized by serum 25OHD level there was an increase in BMD at the total hip and distal radial site at least up to levels of 15 ng/ml. CONCLUSIONS: Despite widespread recognition, hypovitaminosis D is still prevalent among young UK South Asian women. In these women a decrease in serum 25OHD level 相似文献   

老年患者25( OH) D、PTH与骨折的相关分析

目的了解骨科老年患者25-羟基维生素D(25(OH)D)、甲状旁腺激素(PTH)水平及与骨折的相关性。方法2011.8~2014.12我院骨科老年患者428名,72.47±6.19岁,其中骨折192名。测定血清25(OH)D和PTH,腰椎(L1-4)、全髋、股骨颈骨密度。比较骨折与非骨折组25(OH)D,PTH及骨密度的差异;分析25(OH)D、PTH各组骨折和骨密度的差异;分析25(OH)D和PTH、骨密度的相关性;用相对工作特征曲线(relative operating characteristic,ROC curve)分析25(OH)D对骨折的预测价值。结果骨折组与非骨折组相比,25(OH)D水平及全髋和股骨颈骨密度偏低。不同25(OH)D水平组骨折发生的差异具有统计学意义,维生素D严重缺乏组、缺乏组骨折发生率较高。维生素D严重缺乏组、缺乏组、不足组的骨密度偏低,PTH增高组骨密度也偏低。25(OH)D与PTH、腰椎(L1-4)、全髋、股骨颈BMD存在相关性。ROC曲线下面积为0.529,不能以25(OH)D的水平预测骨折。结论骨科老年患者存在严重的维生素D缺乏,维生素D缺乏者骨折发生率明显增高,对其应从补充维生素D、预防跌倒、提高骨质量等多方面进行综合干预。     

Serum intact parathyroid hormone levels in elderly Chinese females with hip fracture

Summary Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)₂D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25 (OH)₂D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture.     

Correlations between Vitamin D Status and Biochemical/Clinical and Pathological Parameters in Primary Hyperparathyroidism

Background To determine the prevalence of vitamin D deficiency and the effects of vitamin D status on parathyroid adenoma weight, clinical and biochemical indices in patients with primary hyperparathyroidism (pHPT) were studied. Methods Eighty patients with pHPT who underwent surgical treatment and in whom the presence of parathyroid adenoma were confirmed histopathologically were studied retrospectively from recorded data files. Patients were divided into three groups: patients with 25-hydroxyvitamin D (25-OHD) concentrations < 15 ng/ml (group 1, n = 44), patients with 25-OHD concentrations > 15–25 ng/ml (group 2, n = 9), and patients with 25-OHD concentrations > 26 ng/ml (group 3, n = 27). Serum calcium, phosphate, alkaline phosphatase, creatinine, and albumin levels and urinary calcium excretion were determined by auto-analyzer. Plasma 25-OHD and parathyroid hormone (PTH) levels were determined by immunoradiometric assay using commercially available kits. Results No statistically significant differences were observed with respect to serum calcium, phosphorus, albumin, and creatinine concentrations between these groups. Serum PTH, alkaline phosphatase concentrations, urinary calcium excretion, parathyroid adenoma weight, and postoperative sixth month PTH concentrations were significantly higher in group 1 patients than in group 2 and group 3 patients. Significant correlations were observed between parathyroid adenoma weight and serum 25-OHD concentrations (r = −0.348, P = 0.020); parathyroid adenoma weight and urinary calcium excretion (r = 0.348, P = 0.021). Multiple regression analysis revealed that parathyroid adenoma weight, serum 25-OHD, and preoperative PTH concentrations correlated independently and significantly with postoperative sixth month PTH concentrations. Conclusions Vitamin D deficiency leads to more severe bone disease, increased parathyroid tumor growth, and delayed postoperative recovery of parathyroid function in patients with primary hyperparathyroidism.     

Prevalence and seasonal variation of hypovitaminosis D and its relationship to bone metabolism in healthy Hungarian men over 50 years of age: the HunMen Study

Summary

This study reports a high prevalence of hypovitaminosis D and low bone mineral density (BMD) in a healthy Hungarian male cohort over 50 years of age. Men with 25-hydroxyvitamin D levels of <75 nmol/L had a significantly higher 10-year hip and major osteoporotic fracture probability using the country-specific fracture risk assessment (FRAX) algorithm.

Introduction

The aim of this study is to characterize the prevalence and seasonal variation of hypovitaminosis D and its relationship to bone metabolism in healthy Hungarian men over 50 years of age.

Methods

We determined levels of 25-hydroxyvitamin D (25-OH-D), PTH, osteocalcin (OC), C-terminal telopeptides of type-I collagen (CTX-I), procollagen type 1 amino-terminal propeptide (PINP), BMD at L1–L4 (LS) and femur neck (FN), daily dietary calcium intake, and the 10-year probability of hip fracture and a major osteoporotic fracture using the country-specific FRAX algorithm in 206 randomly selected ambulatory men.

Results

The mean (range) age of the volunteers was 60 (51–81) years. The prevalence of hypovitaminosis D (25-OH-D, <75 nmol/L) was 52.9%. The prevalence of low (T-score?<??1.0) BMD at the FN and LS was 45% and 35.4%, respectively. The mean (range) FRAX hip fracture and FRAX major osteoporotic fracture was 0.8% (0–9.4%) and 3.8% (1.7–16%), respectively. On comparing the vitamin D sufficient to the insufficient group, there was a statistically significant difference between the FRAX hip fracture and FRAX major osteoporotic fracture indexes. There was significant seasonal variation in the vitamin D levels; the lowest levels were measured in winter and the highest in summer.

Conclusions

A high prevalence of hypovitaminosis D and low BMD were observed in the studied Hungarian male population. This is the first study reporting higher 10-year hip and major osteoporotic fracture probability using the country-specific FRAX algorithm in individuals with hypovitaminosis D.     

Changes in the supporting muscles of the fractured hip in elderly women.

There is little information concerning the changes in the muscles supporting the fractured hip joint. Morphologic and histochemical examinations of biopsy specimen from the middle gluteal muscles were performed at surgery in 42 elderly women with hip fracture caused by a fall. On the basis of serum 25-hydroxyvitamin D (25-OHD) concentration, the patients were divided into a sufficient group (25-OHD concentration >39 nmol/L, n = 20) and a deficient group (25-OHD concentration <39 nmol/L, n = 22). Reflecting the muscular trauma in the fall-induced hip fracture, the following pathologic changes were common in both the sufficient and deficient groups: degenerating and regenerating fibers; fiber necrosis; and inflammatory reaction. The mean type II fiber diameter in the deficient group (15.4 +/- 4.2 microm) was significantly smaller than that in the sufficient group (38.7 +/- 8.1 microm) (p < 0.0001). In the deficient group, the mean type II fiber diameter correlated with the serum 25-OHD concentration (r = 0.714, p = 0.0011). This correlation was not observed in the sufficient group. Low physical activity along with vitamin D deficiency prior to the hip fractures may have caused the severe type II fiber atrophy in the deficient group. Such changes may weaken the support of the hip joint and lead to falls. We believe that severe type fiber II atrophy is an independent risk factor for hip fractures and this should be studied in a classic case-control study. Severe type II fiber atrophy may also have contributed to the poor functional outcome in the deficient group. Further research is needed to develop treatments and rehabilitation protocols that might improve gait and body function by attenuating type II fiber atrophy.     

Abnormal calcium homeostasis in disabled stroke patients with low 25-hydroxyvitamin D

Disabled elderly stroke patients occasionally have very low serum 25-hydroxyvitamin D (25-OHD), which may be due to sunlight deprivation and malnutrition. Many of such patients have very low level of serum 1, 25-dihydroxyvitamin D (1, 25-[OH]2D; calcitriol), and immobilization-induced hypercalcemia may be responsible for inhibition of renal synthesis of calcitriol. To elucidate determinants of serum 1, 25-[OH]2D levels in elderly poststroke patients, we measured serum indices of bone and calcium metabolism and metacarpal bone mineral density (BMD). Patients whose serum 1, 25-[OH]2D concentration was below the mean-3 SD of normal control subjects were defined as the low 1, 25-[OH]2D group and the rest of the patients were designated as the normal group. Mean illness duration was 59 months in the normal group and 20 months in the low group. The Barthel index (BI), which predicts the degree of immobilization, was significantly lower in the low group than in the normal group. Mean serum 1, 25-[OH]2D and 25-OHD concentrations in the normal group were 36.7 pg/ml and 4.4 ng/ml, respectively; and those in the low group were 14.2 pg/ml and 1.8 ng/ml, respectively. Multiple regression analysis identified illness duration and calcium level as independent determinants of 1, 25-[OH]2D in both groups, and PTH in the normal group and 25-OHD in the low group were additional independent determinants. BMD in stroke patients was significantly lower than that in controls, and BMD in the normal group was lower as compared to the low group. BMD correlated negatively with 1, 25-[OH]2D and PTH in the normal group, and hyperparathyroidism may contribute to reduced BMD. These results suggest that treatment of decreased bone mass in stroke patients has to be individualized according to vitamin D status and calcium homeostasis.     

Serum 25-hydroxyvitamin D levels and activities of daily living in noninstitutionalized elderly Japanese requiring care

To date, no study has investigated the nutritional status of vitamin D in frail elderly people living at home. The purposes of this study were to assess serum 25-hydroxyvitamin D (25[OH]D) levels and associated factors in noninstitutionalized elderly people who had various levels of physical disability, and to propose an adequate vitamin D nutritional status for the elderly by interpreting the serum 25(OH)D levels in relation to serum parathyroid hormone (PTH) levels in this population. Health examinations were conducted in the winter and summer of 2003. The subjects were 143 elderly people in the winter, and 120 elderly people in the summer, who all used the long-term care insurance system at home. Serum 25(OH)D concentrations were determined with a chemiluminescence protein-binding assay, and serum intact PTH concentrations were determined with an immunoradiometric assay. The subjects' disease histories and lifestyle information were obtained through an interview. Activities of daily living (ADL) levels were evaluated using the Barthel index, and grip strength was measured with a digital hand dynamometer. Average serum 25(OH)D levels in the winter and summer were 54.2 nmol/l (SD 29.0) and 53.3 nmol/l (SD 32.3), respectively, and intact PTH concentrations in the winter and summer were 4.2 pmol/l (SD 1.8) and 4.3 pmol/l (SD 1.8), respectively. The proportion of people who had a low 25(OH)D (<30 nmol/l) and high intact PTH levels (>6.9 pmol/l) were 15%–20% and 8%, respectively. Significant predictors of low serum 25(OH)D concentrations were low ADL levels, female sex, and low fish consumption in both seasons. Serum 25(OH)D concentrations of less than 50 nmol/l were associated with elevated serum intact PTH concentrations. In conclusion, elderly people requiring care at home are at high risk of hypovitaminosis D, and their low serum 25(OH)D levels are mainly associated with low ADL levels. In addition, maintenance of serum 25(OH)D concentrations above 50 nmol/l may prevent hypovitaminosis D-induced hyperparathyroidism.     

Low Vitamin D Levels in Outpatient Postmenopausal Women from a Rheumatology Clinic in Madrid, Spain: Their Relationship with Bone Mineral Density

To evaluate a possible relationship between vitamin D levels and bone mineral density (BMD) and the prevalence of hypovitaminosis in a population of postmenopausal women from a rheumatologic outpatient clinic in Madrid, Spain, 171 postmenopausal women (aged 47–66 years) divided into two groups (osteoporotic and nonosteoporotic, according to WHO criteria) were studied between November and June. Liver and kidney function were normal in all subjects. Serum parathyroid hormone (PTH) and calcidiol levels were determined and bone densitometry carried out at the lumbar spine and hip level. PTH and calcidiol serum levels did not show any correlation. Serum PTH was inversely related to BMD at both hip and lumbar spine in the total group, and at the hip with calcidiol levels lower than 37 nmol/l. Calcidiol was directly related to hip BMD only when levels were lower than 37 nmol/l. Results of a stepwise multiple regression analysis showed that the single factor which affected BMD at the hip was calcidiol in the subgroup with serum calcidiol levels below 37 nmol/l, while in the subgroup with serum calcidiol levels above 37 nmol/l, the main factor affecting hip BMD was serum PTH. The prevalence of vitamin D deficiency at a cutoff of 37 nmol/l was 64%. In summary, calcidiol serum levels below 37 nmol/l seem to affect bone mass, regardless of the effect of PTH. Vitamin D deficiency is a frequent finding in the postmenopausal women who attend a rheumatology outpatient clinic in Madrid. Vitamin D supplementation should therefore be considered in this population during the winter season. Received: 2 July 1999 / Accepted: 3 March 2000