Calcium-PTH-vitamin D axis in older patients with hip fracture

High prevalence of vitamin D deficiency and osteoporosis in patients with fragility fractures of hip: A pilot study

BACKGROUND

Vitamin D deficiency (VDD) is a major cause of poor bone health that could lead to fragility fractures, however, there is paucity of literature on prevalence of VDD and associated bone mass in patients of fragility fractures. Hip and spine are the commonest region affected by these fractures and the present study was conceptualised to ascertain the prevalence of VDD and bone mass in patients of hip fragility fractures (proximal femur) to evaluate their role in incidence of these fractures.

METHODS AND MATERIALS

Between January 2013 and December 2013, 66 patients of fragility fractures around hip with age more than 50 years presented to our out patient department. Baseline evaluation of calcium profile, renal function tests, parathyroid hormone and 25(OH)D were done. All patients underwent DXA scan of the non -fractured hip.

RESULTS

Total number of male patients was 29 and females was 37, with mean age of 64.1 and 70.3 years, respectively. Intertrochanteric femur fractures were the most common type with 35 cases. Fall in bathroom was the most common mode of injury with 36 cases (54.5%). VDD was found in 74.2% of all patients. Prevalence of secondary hyperparathyroidism was observed in 27 patients. Osteopenia, osteoporosis and severe osteoporosis were observed in 15.2%, 62.1% and 18.2% of patients respectively. Sun light exposure was inadequate in 59% of patients with only 1 female patient having adequate exposure.

CONCLUSION

Prevalence of Vitamin D deficiency is very high in patients with hip fragility (proximal femur) fractures with secondary hyperparathyroidism and osteoporosis commonly associated. These fractures in our part of the world, occur at a younger age group as compared to the Western population. Majority of the patients sustain in-house fractures.

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 levels in post-menopausal Korean women with a distal radius fracture

INTRODUCTION

The purpose of this study was to investigate serum levels of vitamin D in post-menopausal Korean women with a distal radius fracture (DRF) and to determine if there is any association between vitamin D levels and bone-related variables such as bone mineral densities (BMDs), serum parathyroid hormone (PTH) levels and several bone turnover markers.

MATERIALS AND METHODS

The data of 104 postmenopausal women surgically treated for a distal radius fracture (DRF group) and 107 age-matched control patients without a fracture (control group) were compared. Serum vitamin D levels (25-hydroxycholecalciferol, 25(OH)D(3)) were compared between the groups with consideration of age and seasonal variations. BMDs, serum PTH and several bone turnover markers, including serum osteocalcin, C-telopeptide and urine N-telopeptide, were measured and analysed to find any association with vitamin D levels.

RESULTS

The mean 25(OH)D(3) level was significantly lower in the DRF group compared to the control group (p < 0.001). In particular, patients in their sixth and seventh deciles in the DRF group had significantly lower 25(OH)D(3) levels than patients in the control group (p = 0.001 and 0.013, respectively). When seasonal variation was considered, significant differences of 25(OH)D(3) levels were found between the groups in autumn and winter. Hip BMDs were significantly lower in the DRF group than in the control group, and there was a positive correlation between serum 25(OH)D(3) levels and hip BMDs. Bone turnover markers were not significantly different between the two groups, although serum PTH levels were marginally higher in the DRF group (p = 0.08).

CONCLUSIONS

Post-menopausal Korean women with a DRF were found to have significantly lower serum vitamin D levels than the control group, and vitamin D levels were particularly lower in women in their sixth and seventh deciles who may be a good target group for prevention of future fractures. Future investigation should focus on determining whether vitamin D supplementation can be helpful in preventing future fractures in patients with a DRF.

Short and long-term variations in serum calciotropic hormones after a single very large dose of ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3) in the elderly

CONTEXT

In humans, few studies have compared the potencies of ergocalciferol and cholecalciferol in improving and maintaining vitamin D status.

OBJECTIVE

Our objective was to evaluate the effects of a single very large dose of both calciferols on serum changes of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D], ionized calcium, and parathyroid hormone (PTH) at baseline, and at 3, 7, 30, and 60 d.

DESIGN

This was a prospective randomized intervention study.

SETTING

The study was performed in a nursing home residence.

PARTICIPANTS

A total of 32 elderly female patients (age range 66-97 yr), with vitamin D deficiency was included in the study.

INTERVENTION

Participants were randomized into four groups of eight to receive a single dose of 300,000 IU ergocalciferol or cholecalciferol by oral (os) or im route.

RESULTS

25(OH)D levels sharply increased at d 3 only when vitamins were given os. The 30-d basal difference in serum 25(OH)D was significantly greater after cholecalciferol os administration (47.8 +/- 7.3 ng/ml) compared with other forms (D(3) im: 15.9 +/- 11.3; D(2) os: 17.3 +/- 4.7; D(2) im: 5 +/- 4.4; all P < 0.001). The area under the curve (AUC) of the serum 25(OH)D against time (AUC(60)) was: D(3) os, 3193 +/- 759 ng x d/ml vs. D(2) os, 1820 +/- 512, P < 0.001; and D(3) im, 1361 +/- 492 vs. D(2) im, 728 +/- 195, P < 0.01. 25(OH)D significantly influences PTH levels at 3 (P < 0.03), 7 (P < 0.01), 30 (P < 0.01), and 60 d (P < 0.05). At 60 d, the form of vitamin (cholecalciferol) significantly lowers PTH levels (P = 0.037).

CONCLUSIONS

Cholecalciferol is almost twice as potent as ergocalciferol in increasing serum 25(OH)D, when administered either by mouth or im. 25(OH)D plays a role in modulating serum PTH.