Biomedical subjects

L Hyldstrup

Publications and source records attributed to L Hyldstrup.

At least 19 recordsLinked to original sources

PubMed2000

[Proper advice on nutrition. Recommendations concerning the conduct of the nutritional news].

The Committee on Proper Conduct in Public Advice on Nutrition, set up by the Danish Nutrition Council, has produced recommendations to persons involved in communicating results of nutrition research. The guidelines are targeted on scientists, industry, journalists and publishers as well as consumers to facilitate proper conduct in communication of own or other scientists' research results, which might influence consumers' choice and intake of food. The results are presented as recommendations and checklists providing the necessary requirements to bring people in a position to make the best possible evaluation of the new scientific results and to put the results into their proper perspective. The aim of this report is to improve the process so that the communicator focuses on the background information necessary for the reader/listener/viewer in the current situation to achieve a balanced view and benefit from the new scientific result.

Choice Behavior↗

PubMed1999

Bone density reduction in various measurement sites in men and women with osteoporotic fractures of spine and hip: the European quantitation of osteoporosis study.

We have measured bone mineral density (BMD) using dual X-ray absorptiometry (DXA) of the spine and hip, spinal quantitative computed tomography (QCTspi), and peripheral radial quantitative computed tomography (pQCTrad) in 334 spine and 51 hip fracture patients. The standardized hip and spine BMD for each patient was calculated and compared with the combined reference ranges published previously, each densitometer having been cross-calibrated with the prototype European Spine Phantom (ESPp) or the European Forearm Phantom (EFP). Male and female fracture cases had similar BMD values after adjusting for body size, where appropriate. This suggests that the relationship between bone density (mass per unit volume) and fracture risk is similar between men and women. However, compared with age-matched controls, mean decreases in BMD ranged from 0.78 SD units (women with hip fracture, DXAspi) to 2.57 SD units (men with spine fractures, QCTspi). The proportion of spine and hip fracture patients falling below the cutoff for osteoporosis (T-score <-2.5 SD) proposed by the World Health Organization (WHO) study group varied according to different BMD measurement procedures (range 18-94%). This finding suggests that the WHO definition requires different thresholds when used with non-DXA BMD measurement techniques. Receiver operator characteristic (ROC) analysis was used to compare measurement techniques for their ability to discriminate between cases and controls. Among DXA sites, the proximal femur was preferred when evaluating generalized bone loss, particularly in elderly people. An additional spinal BMD measurement may add clinical value if spine fracture risk assessment has a high priority. Both axial and peripheral QCT techniques performed comparably to DXA in spinal osteoporosis, so investigators and clinicians may use any of the three technologies with similar degrees of confidence for the diagnosis of generalized or site-specific bone loss providing straightforward clinical guidelines are followed.

Absorptiometry, Photon↗

PubMed1998

[Alendronate].

Explore the source record for details and available documents.

Alendronate↗

PubMed1998

Calcium and vitamin D supplementation increases spinal BMD in healthy, postmenopausal women.

We undertook a double-masked, randomized, placebo-controlled trial to evaluate the effect of a calcium and vitamin D supplement and a calcium supplement plus multivitamins on bone loss at the hip, spine and forearm. The study was performed in 240 healthy women, 58-67 years of age. Duration of treatment was 2 years. Bone mineral density (BMD) was measured at the lumbar spine, hip and forearm. A dietary questionnaire was administered twice during the study and revealed a fairly good calcium and vitamin D intake (919 mg calcium/day; 3.8 micrograms vitamin D/day). An increase in lumbar spine BMD of 1.6% was observed in the treatment group after 2 years (p < 0.002). In the placebo group no significant changes were observed during the 2 years. Lumbar spine BMD was significantly higher in the treatment group at both 1 (p < 0.01) and 2 years (p < 0.05) compared with the placebo group. Though not significant, the same trend was seen at the hip. No significant changes from baseline values were observed at the distal forearm in either the treatment or the placebo group. In conclusion, we found a significant increase in urinary calcium excretion in the treatment group compared with the placebo group. Together with significant changes in serum calcium and serum parathyroid hormone, this indicates that a long-term calcium and vitamin supplement of 1 g elementary calcium (calcium carbonate) and 14 micrograms vitamin D3 increases intestinal calcium absorption. A positive effect on BMD was demonstrated, even in a group of early postmenopausal age, with a fairly good initial calcium and vitamin D status.

Aged↗

PubMed1998

Bone metabolism in patients with systemic lupus erythematosus. Effect of disease activity and glucocorticoid treatment.

The bone metabolism in patients with systemic lupus erythematosus (SLE) has previously been examined, but the results are conflicting. In the present study the bone mineral density (BMD) of the axial and the appendicular skeleton was examined by means of dual energy x-ray absorptiometry. The bone turnover was evaluated by means of biochemical markers in serum and urine in a prospective cohort consisting of 36 female and male SLE patients. Repeated measurements of BMD were performed for up to two years. The BMD was decreased in the hand and in the femoral neck but normal in the spine and in the distal forearm. A weak correlation was found between the BMD of the femoral neck and the total consumption of glucocorticoids. Apart from this finding the BMD was uninfluenced by treatment with glucocorticoids and cyclophosphamide. No significant changes of BMD were found during the follow-up period. The serum concentration of the carboxyterminal cross-linked telopeptide of type I collagen was increased in almost all patients, but no other biochemical markers of bone metabolism were abnormal.

Absorptiometry, Photon↗

PubMed1997

Effect of vitamin D treatment in hypoparathyroid patients: a study on calcium, phosphate and magnesium homeostasis.

AIM: This study was undertaken to examine the effects of long-term vitamin D treatment on calcium, phosphate and magnesium homeostasis at organ level in hypoparathyroid patients. METHODS: Fifteen vitamin D-treated hypoparathyroid patients were studied, eight of the patients in a combined 47Ca kinetic and calcium, phosphate and magnesium balance study. Results were compared with a matched control group of 12 normal individuals. RESULTS: All the patients had normal serum levels of calcium, phosphate and magnesium. Absolute intestinal calcium absorption was increased (P < 0.0001). Urinary calcium excretion was normal, but active tubular calcium reabsorption (TmCa/glomerular filtration rate) was low (P< 0.001). Bone resorption rates and bone mineralization rates were very low (P < 0.001 and P < 0.05). Twenty-four-hour urinary hydroxyproline excretion and serum cross-linked carboxyterminal telopeptide of type I were in the upper normal range. Serum alkaline phosphatase was normal, but serum carboxyterminal propeptide of human type I procollagen and serum osteocalcin were significantly reduced (P < 0.05). Calcium balance was positive and significantly different from controls (P < 0.001). All parameters from phosphate homeostasis were normal. Intestinal magnesium absorption was low though not significantly different from normal (P = 0.06). Urinary excretion of magnesium was not significantly higher than normal, but renal magnesium reabsorption was reduced (P <0.001). Magnesium balance was low, though the difference was not significant (P < 0.06). CONCLUSION: Long-term vitamin D treatment in hypoparathyroid patients resulted in a positive calcium balance. Bone turnover was very low. Results of bone markers and resorption rate were conflicting. Vitamin D treatment apparently normalized the abnormalities previously found in phosphate homeostasis of hypoparathyroid patients. Magnesium homeostasis was disturbed, with a more negative balance compared with normal subjects, implying a state of magnesium deficiency in these patients.

Adult↗

PubMed1997

Assessment of different markers of bone resorption in postmenopausal osteoporotic women treated with pamidronate.

The aim of this study was to evaluate the different bone resorption markers, total pyridinoline (Pyr) and total deoxypyridinoline (Dpyr), assessed by a HPLC method, free Dpyr, assessed by a new immunoassay, and urinary excretion of hydroxyproline (OH-proline), in postmenopausal osteoporotic women during long-term treatment with pamidronate. A total of 60 postmenopausal women with previous distal forearm fracture were included in this 12-month placebo-controlled and double-blind study, where intermittent oral pamidronate, 75 or 150 mg, or placebo were given daily for 4 weeks, every 16 weeks. After 1 week a significant reduction in urinary excretion of total Dpyr was observed in the group treated with 150 mg pamidronate compared to the placebo (p < 0.01) and to the 75-mg group (p < 0.001). A maximal 50.4% decrease in total Dpyr, (p < 0.0001 compared to the placebo group, p < 0.01 compared to the 75-mg group), was observed after 3 weeks of treatment with 150 mg pamidronate, and this decrease persisted to week 52. After 4 weeks of treatment with 150 mg pamidronate the maximal decrease in free Dpyr was only 26.5%, which persisted during 12 months of treatment. Decreases in urinary excretion of total Pyr and OH-proline were less than the decreases in total Dpyr. The correlation between total Dpyr (HPLC method) and free Dpyr (Pyrilinks-D assay) at baseline was r = 0.91. Total Dpyr assessed by the HPLC method reflects the pamidronate-induced decrease in bone resorption, and the changes in this resorption marker were more pronounced than changes in free Dpyr, total Pyr and OH-proline. In this study free Dpyr analysis was less suitable for reflecting bone resorption during bisphosphonate therapy.

Aged↗

PubMed1996

Bone loss in rheumatoid arthritis. Influence of disease activity, duration of the disease, functional capacity, and corticosteroid treatment.

Axial and appendicular bone mass were studied in 95 patients with rheumatoid arthritis. The aims were to quantify bone mineral density (BMD) and to evaluate the importance of disease activity, duration of disease, functional capacity, and corticosteroid treatment for bone loss in patients with rheumatoid arthritis. The BMD in the lumbar spine (BMDSPINE) did not differ from age-matched healthy controls, but distal forearm BMD (BMDARM) and metacarpal BMD (BMDMCB) were significantly lower in the patients (p < 0.01 and p < 0.001, respectively). Neither BMDSPINE nor BMDMCB were related to the disease activity at the time of investigation. By contrast, BMDARM was decreased in patients with active disease. BMD in any of the three measured locations was not directly correlated to duration of the disease. However, the bone mass in the appendicular skeleton was already decreased within the first two years after the start of the disease. The overall functional capacity in terms of physical activity increased BMD in the axial skeleton. The local functional capacity in terms of grip strength was positively related to BMD in the appendicular skeleton. Patients with severe functional impairment had the lowest BMDARM. The decreased BMD in patients with rheumatoid arthritis seems primarily to be caused by an impaired physical activity which may be related to disease activity. Corticosteroids did not decrease BMD in neither the axial nor the appendicular skeleton. The antiinflammatory effect of steroids lead to clinical improvement, which may counteract the expected negative effect of these drugs on bone in rheumatoid arthritis.

Absorptiometry, Photon↗

PubMed1994

Osteocalcin: a non-invasive index of metabolic bone disease in patients treated by CAPD.

Serum osteocalcin has been found to correlate with bone formation. However, present literature gives only limited data on osteocalcin and bone histomorphometry in patients undergoing peritoneal dialysis. This study assessed serum osteocalcin, dialysate osteocalcin, peritoneal clearance of osteocalcin (Clp-osteocalcin) and mass transfer of osteocalcin (MTp-osteocalcin), and evaluated relationships between these values and bone histomorphometry. Eighteen patients were treated by continuous ambulatory peritoneal dialysis (CAPD). Bone biopsies, serum and dialysate osteocalcin, serum levels of parathyroid hormone, alkaline phosphatase, aluminum, phosphate, Ca2+ and vitamin D3 metabolites were measured at the start and in 10 of the patients a year later. Serum osteocalcin was found to be elevated. Osteocalcin was detected in the dialysate resulting in significant values of Clp-osteocalcin and MTp-osteocalcin. Serum and dialysate levels of osteocalcin correlated significantly (r = 0.66, P < 0.001) and like MTp-osteocalcin with serum levels of alkaline phosphatase and PTH. Histomorphometry showed that osteitis fibrosa was the predominant bone disease detected. Serum concentration of osteocalcin correlated with osteoid thickness, eroded and osteoclast surfaces, aluminum staining, and some of the bone dynamic parameters. Dialysate osteocalcin, MTp-osteocalcin, PTH and alkaline phosphatase correlated with practically the same histomorphometric parameters as serum osteocalcin. No correlations were seen between Clp-osteocalcin and any histomorphometric parameters. Serum osteocalcin was elevated above the normal range, and significant positive correlations between serum osteocalcin and bone formation parameters were found. Serum osteocalcin correlated with almost the same histomorphometric parameters as PTH. Thus, serum levels of PTH and osteocalcin gave additional information to one another as non-invasive parameters in this group of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Acute effect of oral, intraperitoneal, and intravenous 1 alpha-hydroxycholecalciferol on markers of bone metabolism.

OBJECTIVE: To study the acute effect of 1 alpha-hydroxycholecalciferol (1 alpha-OHD3) on serum levels of alkaline phosphatase, Ca2+, osteocalcin, parathyroid hormone (PTH), phosphate and type I and III procollagens (PICP and PIIINP respectively) in patients undergoing peritoneal dialysis. Also, 1,25-(OH)2D3 was measured. DESIGN: Single doses of 1 alpha-OHD3 (80 ng/kg body wt) were given in randomized cross-over fashion, orally, intraperitoneally (i.p.) and intravenously (i.v.) on three occasions. Blood was sampled at 0, 1, 6, 12, and 24 h after administration of 1 alpha-OHD3. MAIN RESULTS: Following oral administration of 1 alpha-OHD3, a decrease in serum alkaline phosphatase was seen when levels at 1 and 6 h were compared to baseline (P < 0.05). Oral and i.v. drug administrations resulted in an increasing trend in serum Ca2+ throughout the study (P < 0.05). Moreover, a difference in serum Ca2+ was found when 24-h levels after oral 1 alpha-OHD3 dose was compared to baseline (P < 0.05). Serum osteocalcin at 12 and 24 h after oral 1 alpha-OHD3 compared to baseline were increased (P < 0.05). Intact PTH followed a circadian rhythm after all three routes of drug delivery. After 24 h, significant decreases of intact PTH were observed in the oral and i.v. group. No changes in serum phosphate and serum PICP levels were observed over time after oral, i.p., and i.v. delivery of 1 alpha-OHD3. However, serum PIIINP following oral and i.p. administration of 1 alpha-OHD3 decreased at 1 and 6 h (P < 0.05). CONCLUSION: Oral and i.v. administration of 1 alpha-OHD3 does influence serum levels of osteocalcin, PTH, and PIIINP: Noticeable is the significant increase in serum osteocalcin after oral administration of 1 alpha-OHD3, the remarkable increase (22.6%) in osteocalcin 24 h after i.v. 1 alpha-OHD3, though not statistically significant, the increase in serum PTH levels 12 h following oral and i.v. doses of 1 alpha-OHD3 and the moderate effect on serum Ca2+ levels.

Administration, Oral↗

PubMed1994

Progressive escape from parathyroid suppression: a common phenomenon in primary hyperparathyroidism (a calcium clamp study).

OBJECTIVE: Induced aggravation of hypercalcaemia in vivo and in vitro causes partial suppression of parathyroid hormone (PTH) secretion in primary hyperparathyroidism (PHP). Furthermore, one in-vitro study also demonstrates progressive escape from such action. The aim of the present in-vivo study was to examine whether escape from suppression is a common feature of PHP. DESIGN: A rapid increment in blood ionized calcium (B-Ca2+) to 0.25-0.30 mmol/l above individual baselines was achieved by intravenous calcium infusions. This induced or aggravated hypercalcaemia was kept constant for 2 hours (controls) or 4 hours (patients). PATIENTS AND CONTROLS: The study of PHP comprised 19 patients (18 females and one male) aged 39-85 years (geometric mean 66). For comparison we included the results obtained in a control group of 24 healthy subjects (11 women and 13 men) aged 20-68 years (geometric mean 32). MEASUREMENTS: The individual levels of B-Ca2+ were controlled by frequent bedside measurements of B-Ca2+. The changes in serum intact parathyroid hormone (S-PTH(1-84)) were registered. RESULTS: After 30 minutes of calcium infusion average concentrations of S-PTH(1-84) had decreased from 7.9 (6.7-9.4) pmol/l in PHP and 2.5 (2.1-2.9) pmol/l in controls to their respective nadir values of 2.9 (2.1-4.1) pmol/l and 0.6 (0.5-0.8) pmol/l. While S-PTH(1-84) remained suppressed at a stable level for 120 minutes in controls, in PHP it started to escape progressively after 30 minutes to a level of 4.2 (3.0-5.8) pmol/l (P < 0.001). Linear regression analysis of the individual S-PTH(1-84) observations in PHP, from 30 to 240 minutes of study, revealed that five patients did not escape (group A) while the remainder 14 patients escaped progressively (group B). Within group B, seven patients escaped significantly after 120 minutes, 10 after 180 minutes and 14 after 240 minutes. Although comparable respecting B-Ca2+ before and during calcium infusion, group A and B presented different S-PTH(1-84) curves. Thus, at times zero, 30, 120 and 240 minutes their respective average concentrations of S-PTH(1-84) measured 9.9 (9.1-10.9) vs 7.3 (5.9-9.0) (P < 0.02), 4.6 (3.7-5.7) vs 2.5 (1.6-3.9) (P < 0.01), 5.0 (3.9-6.5) vs 3.0 (1.9-4.8) (P < 0.05) and 5.2 (3.6-7.4) vs 3.9 (2.6-6.0) (NS) pmol/l. CONCLUSIONS: We hypothesize that two different mechanisms are involved in the parathyroid response to the calcium clamp, an initial and fast inhibition of PTH release, while the subsequent course depends on the balance between the intra-glandular secretion rate of PTH and the intra-glandular capacity for PTH degradation. The escape from parathyroid suppression during a sustained stable increment in B-Ca2+ suggests that the basal secretion over-rides degradation in a majority of the patients with PHP.

Aged↗

PubMed1994

Effect of oral calcium on noninvasive indices of bone formation and bone mass in hemodialysis patients: a randomized double-blind placebo-controlled study.

The purpose of this study was to evaluate the effect of high-dose oral calcium on biochemical indices of bone formation, bone bisphosphonate clearance (BBC) and bone mineral content (BMC) of the distal forearm in patients undergoing hemodialysis. Eighteen patients agreed to participate and were randomized in a double-blind manner to receive either 2 g elemental calcium/day (n = 9) or placebo (n = 9) for 6 months. Previous treatment with aluminum-containing phosphate binders was continued unchanged throughout the study. In the placebo group, serum alkaline phosphatase and osteocalcin tended to increase by 8.0 and 10.2%, respectively, while BBC changed significantly by 49.5% (p < 0.05). In the calcium group the opposite was observed with small decreases in alakline phosphatase and osteocalcin by 8.2 and 11.0%, respectively, and no change in BBC. BMC decreased by 5.0% in the placebo group, but increased by 5.2% in the calcium group, resulting in a difference of 10.2% (p < 0.05). The present study demonstrates that high-dose oral calcium tends to reduce bone turnover and seems able to prevent bone loss in hemodialyzed patients.

Administration, Oral↗

PubMed1994

Cica clamp evaluation of parathyroid responsiveness in chronic hypoparathyroidism: a sequential citrate and calcium clamp study.

The objective of this study was to examine if the Cica clamp technique, sequential citrate and calcium administration sufficient to promote steady-state-blood-ionized calcium concentrations (B-Ca2+) of about 0.20 mmol/l below and above the individual baseline concentrations, was able to produce reciprocal changes in serum intact parathyroid hormone [S-PTH(1-84)] in chronic surgical hypoparathyroidism (HP; n = 10) and chronic idiopathic HP (n = 2). The calcium set point according to Brown [J Clin Endocrinol Metab 1993;56:572-581] was calculated when possible. Data from 22 controls were included for comparison. Within 5-10 min B-Ca2+ lowering in responding patients with surgical HP (n = 7) and controls demonstrated transient S-PTH(1-84) peaks from 1.3 +/- 0.7 to 3.5 +/- 3.2 pmol/l (p < 0.05) and from 3.4 +/- 1.2 to 19.1 +/- 6.7 pmol/l (p < 0.001), respectively. Subsequently S-PTH(1-84) declined to steady-state hypersecretion levels of about 1.9 +/- 1.2 and 8.6 +/- 2.6 pmol/l, respectively. An increase of B-Ca2+ made S-PTH(1-84) unmeasurable in all HP responders except one, while S-PTH(1-84) remained measurable, 0.9 +/- 0.4 pmol/l, in all controls. In responding patients with surgical HP and controls the respective calcium set points averaged 1.05 +/- 0.06 and 1.13 +/- 0.04 mmol/l, respectively (p < 0.001). The remaining nonresponders with surgical and idiopathic HP did not respond at all. To summarize, 7 out of 10 patients with surgical HP demonstrated a normal pattern of parathyroid response to sequential B-Ca2+ decreases and increases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Pharmacokinetic evaluation of pamidronate after oral administration: a study on dose proportionality, absolute bioavailability, and effect of repeated administration.

To evaluate dose proportionality and absolute bioavailability of a new enteric-coated pellet formulation of pamidronate disodium (AREDIA), nine females (aged 52-66 years) were given three different single peroral doses of pamidronate disodium (75, 150, and 300 mg) and an i.v. infusion of 15 mg over 30 minutes at constant infusion rate. Repeated peroral doses (75 and 150 mg) were administered to 12 females (aged 51-70 years) for 10 consecutive days. Urinary excretion of pamidronate after peroral and i.v. administration was used for estimation of pamidronate absorption. Renal excretion of pamidronate ranged from 0.01% to 0.35% of dose, with mean values of 0.11, 0.16, and 0.18% for 75, 150, and 300 mg, respectively. After i.v. infusion, the renal excretion of pamidronate was 26-53% of the dose, lower than for other bisphosphonates. The absolute bioavailability was 0.31% (range 0.08-0.7%) after 75 mg, 0.43% (0.01-1.20%) after the 150-mg dose, and 0.48% (0.07-1.06%) following 300 mg of pamidronate disodium. Urinary excretion after the 10th intake showed a significant increase (difference 0.07% (range -0.003-0.29%), P < 0.02) when compared with the first dose. In conclusion, intestinal uptake of pamidronate was low with high intraindividual variation, like other bisphosphonates.

Administration, Oral↗

PubMed1993

Oral calcium effectively reduces parathyroid hormone levels in hemodialysis patients: a randomized double-blind placebo-controlled study.

The objective of this study was to elucidate the effect of oral calcium supplement upon the severity of secondary hyperparathyroidism and hyperphosphatemia in patients undergoing hemodialysis. Twenty-three accepted to participate and were randomly allocated to receive in a double-blind manner either 2 g elemental calcium per day (n = 12) or placebo (n = 11) for 6 months. Three patients dropped out leaving 10 patients in each group. In the calcium group serum ionized calcium increased significantly during the 1st month from 1.15 +/- 0.02 to 1.29 +/- 0.04 mmol/l (mean +/- SE) and was then stabilized at an average of 1.26 +/- 0.02 mmol/l for the remaining 5 months. Serum intact parathyroid hormone (PTH) decreased in average by 54% within the 1st month and remained at that level for the following months. Hyperphosphatemia remained stable throughout. On the contrary, in the placebo group, serum concentrations of ionized calcium and intact PTH remained unchanged, while serum phosphate increased significantly. The present study demonstrates that oral calcium reduces secondary hyperparathyroidism and prevents the progression of hyperphosphatemia in patients undergoing hemodialysis.

Adult↗

PubMed1993

Bone metabolism in obesity: changes related to severe overweight and dietary weight reduction.

A non-invasive evaluation of bone metabolism was performed in 44 morbidly obese patients before and after a mean weight loss of 22.4 kg (range 7.9-43.4 kg) after 2 months and a further weight loss of 7.3 kg after 8 months (0.8-20.0 kg). This weight reduction was obtained by a nutritionally adequate very-low-calorie diet. Before treatment the bone mineral content of the distal forearm was increased compared to normals (51.9 U vs. 43.7 U, p < 0.001). Bone formation was evaluated by serum alkaline phosphatase and serum osteocalcin. Serum alkaline phosphatase was increased (187.8 U/l vs 147.4 U/l, p < 0.001) while serum osteocalcin was lower than in the controls (0.67 nmol/l vs 0.98 nmol/l, p < 0.01). Bone resorption, as measured by the urinary hydroxyproline/creatinine ratio, was not increased in the obese patients (19.2 molar ratio x 10(-3) vs 16.7 molar ratio x 10(-3), NS). After 2 months, the bone mineral content had declined by 3.3%. Serum alkaline phosphatase remained unchanged (187.8 U/l vs 186.9 U/l, NS) but serum osteocalcin demonstrated a significant rise (3.94 nmol/l vs 10.53 nmol/l, p < 0.001), parallel to changes in the hydroxyproline/creatinine ratio (19.2 molar ratio x 10(-3) vs 25.2 molar ratio x 10(-3), p < 0.001). At 8 months, no further change in the bone mineral content was seen. The hydroxyproline/creatinine ratio did still increase (from 25.8 molar ratio x 10(-3) to 30.1 molar ratio x 10(-3), p < 0.05), while serum alkaline phosphatase and serum osteocalcin remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Bisphosphonate kinetics in patients undergoing continuous ambulatory peritoneal dialysis: relations to dynamic bone histomorphometry, osteocalcin and parathyroid hormone.

In the evaluation of renal osteodystrophy bone biopsy is often performed. However, a reliable noninvasive test could be very useful, and recently the estimation of osseous tracer uptake as an index of bone formation has been introduced-the bone bisphosphonate clearance (BBC). The aim of the present investigation therefore was to compare BBC with parameters of bone histology, serum levels of osteocalcin, alkaline phosphatase, and parathyroid hormone in patients (n = 8) undergoing continuous ambulatory peritoneal dialysis (CAPD). No significant correlations were found between BBC values and the bone histomorphometrical variables measured. A positive correlation was seen between serum osteocalcin and resorption and active resorption surface (p < 0.05), as well as tetracycline-labelled surface, bone formation rate, surfaces, volume and tissue referents, respectively (p < 0.01). Furthermore, levels of alkaline phosphatase showed significant correlations to mineral appositional rate, tetracycline-labelled surface and bone formation rate, volume referent (p < 0.05). Values of parathyroid hormone were significantly correlated to resorption surface (p < 0.02), active resorption surface, mineral appositional rate and mineralization lag time (p < 0.05). In conclusion, BBC was of no use in patients treated with CAPD as a noninvasive test for evaluation of bone histomorphometry. However, osteocalcin correlated best with resorption and bone dynamics indices. Levels of alkaline phosphatase and parathyroid hormone were of a more limited value.

Adult↗

PubMed1992

Late Calcium Metabolic Consequences of Jejuno-ileal Bypass.

Seventeen patients with previous jejuno-ileal bypass operation (JIB) for obesity were included in a follow-up study 11 to 19 years after JIB. Evaluation of calcium-parathyroid hormone axis was performed by a highly sensitive two-site IRMA assay for serum intact parathyroid hormone and serum ionized calcium. Evidence of a varying degree of secondary hyperparathyroidism was found. The observed hyperparathyroidism was of clinical significance in a subpopulation characterized by increased bone turnover and reduced bone mineral content. As a consequence, the calcium metabolism with special attention to the parathyroid function must be carefully monitored in JIB patients. Serum ionized calcium alone and vitamin D metabolites do not identify patients at risk of bone loss.

Journal Article↗