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J L Sebert

Publications and source records attributed to J L Sebert.

At least 37 records · Page 2Linked to original sources
PubMed1996

Different responses of free and peptide-bound cross-links to vitamin D and calcium supplementation in elderly women with vitamin D insufficiency.

Recent findings have shown that bisphosphonates had different effects on the urinary excretion of free and peptide-bound cross-links. Because of this discrepancy, we investigated the effects of another antiresorptive therapy, i.e. vitamin D (vitD) and calcium (Ca) supplementation (800 IU vit D3 and 1 g elemental calcium daily for 6 months) in elderly women (n = 21, age: 83.5 +/- 1.5 yr) with vitD insufficiency and secondary hyperparathyroidism (mean level 25 hydroxy vitamin D = 3.17 +/- 1.2 ng/mL, mean level of intact parathormone = 45.3 +/- 22.7 pg/mL) on the urinary excretion of free and peptide-bound cross-links. A group of free-living, healthy elderly women (n = 25, age: 76.6 +/- 3.1 yr) with a normal vitD status (mean level of 25 OH D = 23.4 +/- 8.9 ng/mL, intact parathormone = 30.2 +/- 11.2 pg/mL) was simultaneously studied. Bone resorption was assessed by total (T), free (F), peptidyl (P) hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) measured with high performance liquid chromatography, by F-LP determined with enzyme linked immunosorbent assay (iF-LP) and by the N- and C-terminal telopeptides of type I collagen (NTX and Cross-laps) before and after (3 and 6 months) therapy. Comparison of the two groups of elderly women at baseline showed that the urinary excretion of pyridinoline cross-links (T, F, and peptide-bound forms) and of telopeptide fragment of type I collagen were all increased in patients with a low vitD status. Highly significant differences were seen principally for T-HP, F-HP, and F-LP (P < 0.001). Correlation studies between each marker showed that the values of pyridinoline cross-links (T and peptide-bound forms) and of the telopeptide fragments of type I collagen correlated well, but the correlation was slightly less pronounced between free pyridinolines and the other markers. After treatment, the response to therapy was greatest for peptide-bound cross-links assessed by high performance liquid chromatography and for telopeptide fragments of type I collagen (percent change at 6 months: -21% for P-HP P < 0.05, -26% for P-LP P < 0.05, -31% for NTX P < 0.01, and -51% for CLaps P < 0.001). In contrast, free pyridinolines excretion (F-HP and F-LP) assessed by high performance liquid chromatography as well as by immunoassay remained unchanged at 3 and 6 months. Because marked and significant changes were seen with peptide-bound cross-links only and not with free forms, we conclude that vitD and Ca therapy has the same effects as bisphosphonates on the urinary excretion of free and peptide-bound cross-links. So far, no rational mechanism can be given to explain this discrepancy, and further studies are needed before routine application of these bone collagen degradation products as bone resorption markers.

Aged↗
PubMed1996

How do French rheumatologists treat early rheumatoid arthritis?

Although factors that appear to predict long-term outcomes of rheumatoid arthritis have been identified, there is no consensus about the treatment early in the disease. To determine how French office- and hospital-based rheumatologists treat early rheumatoid arthritis, we created three clinical vignettes corresponding to different levels of severity of early rheumatoid arthritis (less than six months' disease duration). Cases 1 and 2 were relatively young patients (35 and 50 years), and Case 1 had numerous poor prognosis factors. Case 3 was 80 years of age. Rheumatologists were asked to indicate which medications they would use at presentation and after one year of a favorable or unfavorable course. The study was conducted by questionnaire (response rate, 58%). Of the 185 rheumatologists who completed the questionnaire, 81% were male and 19% female; mean age was 42 +/- 8 years. In Cases 1 and 2, nonsteroidal antiinflammatory drugs were given by 99% of respondents; second-line drugs were prescribed at presentation by 93% of respondents in Case 1 and 86% in Case 2, and methotrexate was more likely to be used in the presence of poor prognosis factors (23% in case 1 and 7% in Case 2). In the event of an unfavorable course after one year, a larger proportion of rheumatologists prescribed glucocorticoid therapy (65% in Case 1 and 20% in Case 2), and there was a shift from "conventional" to "modern" second-line drugs, with more widespread use of methotrexate (65% in case 1 and 18% in case 2). In the 80-year-old patient, glucocorticoid therapy was used more often than nonsteroidal antiinflammatory drugs and second-line drugs (gold salts, hydroxychloroquine, sulfasalazine) were prescribed by 40% of rheumatologists at presentation and by 67% after one year of an unfavorable course; in the latter situation, methotrexate was selected in 24% of cases. In contrast to conventional recommendations, many French office- or hospital-based rheumatologists use second-line drugs very early and base their choice of medications on the estimated risk of severe disease and on the age of the patient.

Adult↗
PubMed1996

[Urinary excretion of free and total deoxypyridinoline during secondary hyperparathyroidism in the elderly. Comparison of chromatographic (HPLC) and immunoenzymatic (Pyrilinks-D) methods].

The measurement of urinary deoxypyridinoline (DPD) constitutes a specific and sensitive marker of bone resorption. Total and free forms of DPD are determined by chromatographic method (HPLC) after or without hydrolysis of urine, respectively. Pyrilinks-D, a new immunoassay, allows to assess directly the free forms and needs an appropriate hydrolysis step for measuring the total form. We have compared the values of free (F), total (T) and conjugated (NF) forms of DPD determined by HPLC and Pyrilinks-D, in elderly women (n = 21, mean age: 83.5 +/- 1.5 years) with vitamin D insufficiency (25 OH D < 6 ng/mL) and Ca insufficiency responsible for a secondary hyperparathyroidism (iPTH = 45.3 +/- 22.7 pg/mL) and in healthy elderly women (n = 25, mean age: 76.6 +/- 3.1 years) with a normal vit D status (25 OH D > 10 ng/mL) as control group. We have also measured DPD during the course of vit D and Ca supplementation. At baseline, the HPLC and Pyrilinks-D values of DPD/Cr are highly correlated (DPD-T: r = 0.92, p < 0.001 and DPD-F: r = 0.76, p < 0.001), DPD-F and -NF values are correlated with those of DPD-T, while DPD-F and -NF are not correlated between themselves. In elderly with vit D insufficiency, the values obtained with Pyrilinks-D as compared to control subjects, show a significant increase of urinary excretion of DPD-F (8.5 +/- 3.1 vs 5.7 +/- 1.9 nmol/mmol, Cr, p < 0.0001), DPD-T (16.8 +/- 10.2 vs 9.9 +/- 3.5 nmol/mmol, Cr; p < 0.001) and DPD-NF (8.3 +/- 9.0 vs 4.5 +/- 3.3 nmol/mmol, Cr, p < 0.05). The administration of 800 IU of vit D and 1 g of elemental Ca during a course of 6 months normalize the iPTH values (24.4 +/- 11.8 and 30.9 +/- 14.6 pg/mL at 3 and 6 months). Simultaneously, the urinary excretion at 3 and 6 months of DPD-T (12.9 +/- 6.0 and 13.6 +/- 6.5 nmol/mmol, Cr) and of DPD-NF (4.5 +/- 3.3 and 5.5 +/- 4.8 nmol/mmol Cr) assessed by Pyrilinks-D as well as by HPLC decreased significantly, while no change was seen with DPD-F assessed by both methods. The decreases expressed as percent of baseline values were about 20% for DPD-T and more than 30% for DPD-NF, while DPD-F levels remain unchanged. We conclude that the Pyrilinks-D immunoassay presents reliable characteristics and allows to assess either free or total forms of DPD, like the HPLC technique. It constitutes an excellent reflection of bone resorption in elderly with vit D insufficiency. However its application to monitor therapy like vit D and Ca supplementation, needs a hydrolysis step to determine DPD-T which appears in this study more sensitive to the treatment than DPD-F.

Aged↗
PubMed1995

A simple and automated HPLC method for determination of total hydroxyproline in urine. Comparison with excretion of pyridinolines.

An HPLC method for measuring total hydroxyproline in human urine was validated. Hydroxyproline derivatization was achieved with 9-fluorenylmethyl chloroformate after blocking primary amino acids with orthophthaldialdehyde. The derivatives (hydroxyproline and internal standard) were separated by reversed phase high-performance liquid chromatography and detected by absorbance at 254 nm. Duplicate measurements of hydroxyproline have a coefficient of variation of 3.9% and the recovery in spiked urine samples is between 99.5 and 100.8%. We have compared the HPLC procedure with a commercial colorimetric assay. Analytical criteria of these methods are identical. Regression analysis, involving 50 samples, shows an excellent correlation between hydroxyproline chromatographic (y) and colorimetric (x) procedures: y = 0.989x + 2.99 (r = 0.976). Hydroxyproline excretion was determined in urine samples from 76 women more than 5 years post-menopause. The mean hydroxyproline/creatinine ratio in this group was 19.3 +/- 5.6 mumol/mmol (range 10.6-34.7). Finally, we compared in the same urinary samples hydroxyproline excretion with pyridinoline excretion (hydroxylysylpyridinoline and lysylpyridinoline), a new marker of bone resorption. The values show a significant correlation, with r = 0.417 for hydroxylysylpyridinoline and r = 0.443 for lysylpyridinoline.

Aged↗
PubMed1995

Multiple molecular forms of pyridinolines cross-links excreted in human urine evaluated by chromatographic and immunoassay methods.

The measurement of the collagen cross-links, hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), excreted in urine either in free or peptide-bound forms represents the most extensively investigated biochemical marker of bone collagen degradation. We studied the urinary molecular forms of pyridinolines after separation in free and peptide-linked fractions by chromatography and serial dialysis. The pyridinoline amounts of molecular species (free, < 1000 D, 1000-3500 D, 3500-10,000 D, and > 10,000 D) were evaluated by high performance liquid chromatography (HPLC) as well as with the two newly introduced enzyme-linked immunosorbent assay (ELISA) methods for determination of free pyridinolines (collagen Pyrilinks and collagen Pyrilinks-D). The variability of urinary pyridinoline forms were studied in healthy adult control subjects (n = 10, 38.4 +/- 7.5) years), in adolescents (n = 10, 16 +/- 3.3 years), and in elderly subjects with vitamin D insufficiency (n = 10, 87.3 +/- 4.3 years). Free and peptide-conjugated pyridinolines with MW < 1000 D constitute the major part of urinary cross-links in all groups, with a significantly lesser excretion in elderly patients than in adolescent groups. Expressed as a percent of total cross-links, urinary free pyridinolines assessed by direct HPLC are less in elderly subjects (HP = 34.2 +/- 6.2%, LP = 32.7 +/- 7.6%) than in adolescents (HP = 45.8 +/- 10.8%, p = 0.0065 and LP = 47.8 +/- 12.1%, p = 0.012) and in healthy adults (HP = 39.3 +/- 11.5%, NS and LP = 38.1 +/- 9.3%, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Markers of bone remodeling in the elderly subject: effects of vitamin D insufficiency and its correction.

The elderly subject is prone to both vitamin B insufficiency and calcium insufficiency due to a low calcium intake and calcium malabsorption. These two alterations may lead to secondary hyperparathyroidism, and thus to increased bone loss. We investigated 72 elderly subjects (16 men and 56 women) with vitamin D insufficiency and 25 healthy elderly women with normal vitamin D status, with respect to their indices of calcium metabolism and of bone remodeling: serum total alkaline phosphates (phosphatases), bone AP (BAP), osteocalcin (BGP), tartrate-resistant acid phosphatase (TRAP), urine hydroxyproline (HYP), and the 3-OH-pyridinium derivatives pyridinoline (PYD) and deoxypyridinoline (DPD), which are new markers of bone resorption. We then studied the modifications of these markers in the patients with vitamin D insufficiency at 3 months and 6 months after onset of a daily vitamin D and calcium supplementation. When compared with elderly subjects with normal vitamin D status, patients with vitamin D insufficiency had increased intact parathyroid hormone (iPTH) levels (60.1 +/- 10.2 vs 30.2 +/- 4.5, p < 0.001) and a high bone turnover as reflected by increased values of most serum and urine markers of bone remodeling. PYD and DPD levels were significantly correlated with all indices of bone turnover, unlike HYP, which showed no correlation with bone formation markers (AP, BAP, and BGP). A daily supplement of 800 IU vitamin D3 and 1 g of elemental calcium increased 25(OH)D levels and induced a dramatic decrease of iPTH levels; at 3 and 6 months, the mean iPTH level decreased by 50% (p < 0.0001), reaching the mean value of healthy vitamin D sufficient elderly women. All markers of bone turnover, except TRAP, decreased significantly at 3 and 6 months. The PYD/DPD ratio increased significantly at 3 and 6 months. The decrease of bone markers was more marked in patients with more severe hyperparathyroidism, the greatest variations being obtained with BAP (45%, p = 0.006) and DPD (43%, p = 0.036) levels. Most markers of bone remodeling are increased in elderly subjects with vitamin D insufficiently and vary with its correction. However, BAP and DPD are the most sensitive indicators of increased bone turnover due to secondary hyperparathyroidism.

Aged↗
PubMed1995

Monofluorophosphate increases lumbar bone density in osteopenic patients: a double-masked randomized study.

To assess the efficacy of combined sodium monofluorophosphate and calcium therapy (FC) in increasing lumbar bone mineral density (BMD) in patients with low bone mass, we conducted a prospective double-masked randomized study in 94 patients aged 50-70 years. Patients were selected on the basis of a lumbar BMD at least 2 standard deviations (SD) below the young adult mean (T-score) but without evidence of previous vertebral fracture (severe osteopenia). They were randomly assigned to receive for 2 years, twice a day, either FC (13.2 mg F-, i.e. 100 mg sodium monofluorophosphate, and 500 mg Ca2+) or C (500 mg Ca2+). Vertebral BMD was measured by dual photon absorptiometry from L2 to L4. Comparison at final assessment in the 76 eligible patients (Student's t-test) showed a statistically significant difference between the two groups in the mean BMD increase in favour of FC. Furthermore, Student's t-test showed a significantly greater increase in lumbar BMD in FC-treated patients at 1 year, at 18 months and after 2 years (mean increase of 7.1%/year). These results were confirmed by ANOVA at 1 year, at 18 months and after 2 years of treatment. Of the FC-treated patients, 71.4% were considered to have responded (i.e. they showed an increase in lumbar BMD of more than 0.034 g/cm2). The dosage of 26.4 mg fluoride ion/day (i.e. 200 mg monofluorophosphate/day) therefore appears to be safe and to increase the BMD effectively in patients with low bone mass prior to vertebral fracture.

Absorptiometry, Photon↗
PubMed1995

[Bone involvement in idiopathic calcium lithiasis].

Bone involvement in idiopathic calcium nephrolithiasis is characterized by the following abnormalities: a) the bone density is decreased, the severity of bone loss being dependent upon the existence of hypercalciuria and upon the pathophysiology of this latter: it is inconsistent in the absence of hypercalciuria or when hypercalciuria is of the absorptive type I or II, whereas it is almost constant in fasting hypercalciuria without secondary hyperparathyroidism and constant and severe in the rare true renal hypercalciuria. b) The bone histology (which has been evaluated only in idiopathic hypercalciuric patients) mainly shows a defect in bone formation at the exception of the rare renal hypercalciuria. Osteoclastic hyperresorption is only seen in this latter type of hypercalciuria whereas in the other types of hypercalciuria only an increase of the total or inactive resorption surface is observed. This phenomenon is possibly explained only by a delayed refilling of the resorption lacunae secondary to the decreased bone formation. The osteoid thickness is either normal or decreased despite decrease in mineralization apposition rate which seems therefore to be secondary to the decreased bone formation. c) Symptomatic bone disease in hypercalciuric stone formers is exceptional and always related to a severe long term calcium restriction. d) The biochemical markers of bone resorption tend to be increased in idiopathic hypercalciuria. Hydroxyprolinuria is more often elevated than pyridinolinuria. However pyridinolinuria is negatively correlated to bone density. The contrast between the increase of these bone resorption markers and the usual normality of plasma PTH and of the osteoclastic resorptive surfaces, suggest the role of meat induced acid load which may favor inactive resorption by dissolution of bone buffers. A disturbed profile synthesis of cytokines which induce differentiation and proliferation of the osteoclasts and which modulate the osteoblastic proliferation and function (IL-1, IL-6, TNF-alpha, GM-CSF...) may play a role in the bone loss of calcium stone formers but further studies are necessary to precise its transient or permanent involvement in their bone disease. e) The decrease of bone formation may be explained by the suppressed PTH secretion which may be explained by hypercalcitriolemia. This excess of calcitriol synthesis may be secondary either to monocyte increased synthesis of IL-1 which stimulates the renal 1 alpha-hydroxylase by the mean of an increased PGE2 synthesis or to the relative hypophosphatemia of the calcium stone formers comparatively to healthy controls. Hypercalcitriolemia may originate from the activated monocyte itself. The decrease in bone formation may also be secondary to the action of monokines on the osteoblast differentiation and/or function.

Animals↗
PubMed1995

Evaluation of a new solid formulation of calcium and vitamin D in institutionalized elderly subjects. A randomized comparative trial versus separate administration of both constituents.

Supplementation with 800 IU of vitamin D and 1 g of calcium each day is recommended in institutionalized elderly subjects to prevent secondary hyperparathyroidism and its adverse skeletal effects. An original formulation (IDEOS) combining vitamin D and calcium has been developed for use in this end. The aim of this study was to determine whether administration of this association, of which each tablet contains 500 mg calcium and 400 IU vitamin D3, produces the same beneficial effects on laboratory parameters as separate administration of both active agents. A multicenter randomized study was conducted in 91 elderly institutionalized subjects (mean age 83.1 years) who had vitamin D deficiency [25-(OH)D < 6 ng/ml] without severe renal failure. Subjects were randomly assigned to one of the two treatment groups. Treatment duration was six months. One group (G1, n = 46) received one tablet of the new formulation twice daily. The other (G2, n = 45) received 8 drops of vitamin D3 (800 IU/day) and one calcium carbonate 500 mg tablet twice daily. Blood tests were carried out at inclusion and after three and six months of treatment. In group G1, plasma 25-(OH)D levels increased from 2.6 ng/ml at inclusion to 14.6 ng/ml at month 6 (p < 0.001), and iPTH fell from 63.2 pg/ml at inclusion to 33.8 pg/ml at month 6 (p < 0.001). In group G2, 25-(OH)D rose from 2.8 ng/ml at inclusion to 13.5 ng/ml at month 6 (p < 0.001), and iPTH fell from 55.4 pg/ml at inclusion to 32.5 pg/ml at month 6 (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Prevalence and biological consequences of vitamin D deficiency in elderly institutionalized subjects.

The prevalence of vitamin D deficiency was evaluated in a population of elderly institutionalized subjects in seven long-term geriatric care facilities in France (Amiens, Francheville, Ivry, Lille, Montpellier, Oissel and Villejuif). Residents whose functional capability was relatively good were entered into the study. There were 126 patients (99 females and 27 males) with a mean age +/- SD of 84 +/- 6.6 years. All subjects had been institutionalized for over six months and were capable of walking at least as far as the dining room. None had received vitamin D or other compounds known to affect the metabolism of phosphorus and calcium within six months before the study. Vitamin D status was evaluated by determining serum 25 hydroxyvitamin D (25 OH D) levels using a radiocompetition assay after extraction and chromatographic separation. Mean serum 25 OH D was 3.17 +/- 2.52 ng/ml (median 2.5). Eighty-five per cent of subjects had serum 25 OH D values of less than 5 ng/ml and 98% had values under 10 ng/ml, which is the cutoff usually taken to define vitamin D deficiency. Mean serum levels of intact parathyroid hormone were increased approximately two-fold as compared with values in healthy adults (70 +/- 39 pg/ml versus 33 +/- 12 pg/ml). Biochemical markers for bone formation (alkaline phosphatase, osteocalcin) and bone resorption (TRAP, hydroxyproline, pyridinoline) were all increased, with mean values 1.4-fold to 3.4-fold those seen in healthy adults. Serum 25 OH D levels were negatively correlated with serum intact parathyroid hormone levels (r = 0.41; p < 0.0001). Serum intact parathyroid hormone levels were positively correlated with alkaline phosphatase activity (r = 0.30; p < 0.001) and serum osteocalcin levels (r = 0.36; p < 0.0001) and negatively correlated with corrected serum calcium levels (r = -0.20; p < 0.02). Conclusion. Our data demonstrate that severe vitamin D deficiency is present in virtually all elderly institutionalized subjects and is accompanied with secondary hyperparathyroidism responsible for increases in markers of bone remodeling. Routine vitamin D supplementation is warranted in elderly institutionalized subjects.

Adult↗
PubMed1994

Urinary excretion of pyridinolines crosslinks measured by immunoassay and HPLC techniques in normal subjects and in elderly patients with vitamin D deficiency.

Hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) are specific constituents of mature skeletal collagens excreted in urine. Their measurement represents a sensitive index of bone resorption. In this study, we have measured urinary excretion of pyridinolines crosslinks by immunoassay (ELISA) and HPLC methods in 80 patients with different bone resorption rates. We chose a sample of 44 healthy adults (30 men and 14 women) and a sample of 36 elderly patients (7 men and 29 women) presenting a secondary hyperparathyroidism due to a vitamin D deficiency. The correlation between HPLC (x) and ELISA (y) was judged satisfactory (y = 0.794x + 6.947, r = 0.92). The sensitivity of pyridinolines estimation was 50 nmol/l for immunoassay and 20 nmol/l for HPLC. The intra-assay and inter-assay coefficients of variation for the two analytical methods was < 10%. The mean excretion of crosslinks (nmol/mmol of creatinine) measured by both methods in the sample of healthy adults was higher in women than in men. The amount of pyridinolines crosslinks excreted by elderly patients with vitamin D deficiency are three time higher than those of normal adults when measured by ELISA and HPLC methods. The distribution of different molecular forms of urinary pyridinoline crosslinks was investigated. Values of pyridinolines measured by HPLC in our samples of elderly patients have shown that free and peptide-bound pyridinolines with molecular weight (mol. wt.) smaller than 1000 Da represent approximately 80% of the total pyridinolines contained in urinary samples. A study on the evaluation of the antiserum used in the immunoassay for reacting with the different molecular forms isolated from urine showed a high affinity for free and peptide-bound pyridinolines with molecular weight smaller than 10,000 Da and that do not react strongly with peptide-bound with molecular weight greater than 10,000 Da. We conclude that, although this immunoassay does not measure total pyridinolines and does not distinguish between HP and LP, it seems convenient for diagnostic of metabolic bone diseases.

Adult↗
PubMed1993

Fractures of the proximal femur in Picardy, France, in 1987.

Between 1 January and 31 December 1987, 1178 hip fractures were recorded in the 28 clinical centres, public and private, of the Picardy region (19443 km2, 1.8 million inhabitants). Patients under 20 years and those with metastatic cancer and myelomatous fractures were excluded. Women sustained 853 fractures (age mean +/- SD: 80.2 +/- 10.4 years) and men 325 (age 69.7 +/- 16.0 years). The crude incidence rate per 10,000 person years was 13.4 for women and 5.4 for men (female/male ratio 2.6). These incidences are among the lowest recorded in Northern Europe. Women with trochanteric fractures were older than those with cervical ones, but no difference was observed for men. After adjusting for age and sex, the incidence of hip fracture was greater in urban (10.5 per 10,000 person years) and semi-rural areas (8.2) than in rural areas (5.3). The mean bed-days per patient (+/- SD) was 21.6 +/- 16.0 (quartiles: 13-17-26 days); no difference was observed between sex or age classes. The in-hospital mortality rate was 8.7%, it increased with age and was higher in men, whatever their age. We review the data in different countries, mostly European, to compare with the Picardy region.

Adult↗
PubMed1993

Renal osteodystrophy and hypercalcemia.

The occurrence of aluminum-related bone disease should be completely prevented in uremic patients by restricting the use of aluminum-phosphate binders, which can be safely replaced by oral calcium carbonate. Factors other than aluminum may lead to adynamic bone disease in uremic patients. Radiolucent bone cysts are indicative of amyloid deposits, and their occurrence and progression may be influenced by the membranes used for hemodialysis. Bone disease may persist after successful renal transplantation, and the additional deleterious effect of immunosuppressive drugs should be emphasized. Primary hyperparathyroidism is the most frequent cause of hypercalcemia in the general population. Surgery should be undertaken when there is evidence of active disease, even in asymptomatic patients. The consequences of primary hyperparathyroidism on bone mass and bone fragility remain controversial, and histologic bone studies suggest that hyperparathyroidism leads to increased bone turnover without any deleterious effect on bone volume or trabecular architecture. The diagnostic value of a newly developed immunoassay for intact parathyroid hormone and parathyroid hormone-related protein is clearly demonstrated. New bisphosphonates are of major value for the management of hypercalcemia in malignancy.

Aluminum↗
PubMed1993

Effect of sex and age on the ratio of cervical to trochanteric hip fracture. A meta-analysis of 16 reports on 36,451 cases.

We analyzed 15 published reports and our own data. In women, the ratio of cervical to trochanteric fractures (C/T) evolved in 3 periods. 1) Before the age of 50 years, the annual incidence of cervical fracture is close to that of trochanteric fracture. 2) Between 50 and 60 years, cervical fracture increases markedly, and the C/T ratio is well above unity at an age when the fracture incidence is still very low. 3) This imbalance progressively diminishes to reach unity in the very old, as the result of a progressive increase in trochanteric fractures. In men, cervical fractures are progressively more common with increasing age, and the C/T ratio exceeds unity after 70 years of age. In both genders, the incidence of cervical fracture is thus greater than that of trochanteric fracture during a limited period of time, in the perimenopausal period for women and in elderly men. Several hypotheses on the mechanics of falls and bone strength have been advanced, without any satisfactory explanation for the C/T sex and age changes.

Age Factors↗
PubMed1992

Non-aluminic adynamic bone disease in non-dialyzed uremic patients: a new type of osteopathy due to overtreatment?

Adynamic bone disease, characterized by a low bone formation rate with normal or reduced amount of unmineralized osteoid, is supposed to be the consequence of aluminum intoxication in uremic patients. However, the emergence of adynamic bone disease has been recently reported in hemodialyzed patients in the total absence of aluminum overload. This study was aimed to assess whether such a histological pattern of adynamic bone disease was already present in uremic patients not yet on dialysis. Twenty-seven asymptomatic uremic patients (mean age +/- SD 43 +/- 10 years, mean creatinine clearance 19 +/- 3 ml/mm) were studied and bone biopsies were repeated in 16 of them after 18 +/- 10 months of treatment with oral calcium carbonate (1-3 g of elemental calcium/day) and calcidiol (21 +/- 14 micrograms/day). None of the patients received aluminum hydroxide, and the search for bone aluminum deposits was negative in all patients both before and after treatment. Two patients fulfilled the criteria of adynamic bone disease on their post-treatment biopsies. They originated from patients classified as having normal bone histology before treatment. Comparison with the other patients showed that they had comparable plasma C-terminal PTH but higher plasma creatinine than patients with normal bone histology and lower plasma C-terminal PTH than patients with osteitis fibrosa but comparable plasma creatinine. The plasma levels of 1,25(OH)2D reached values above normal after treatment in these two patients. It is suggested that adynamic bone disease not related to aluminum intoxication can develop in uremic patients independently of dialysis, and is favored by a relative hypoparathyroidism for the degree of renal failure, possibly induced by elevated plasma concentrations of calcitriol.

Adult↗
PubMed1991

[Bone density in idiopathic hypercalciuria in men. Study by dual photon absorptiometry, X-ray computed tomography and histomorphometry].

Lumbar bone mineral density (BMD) of the L3 vertebra was evaluated by double photon absorptiometry or tomodensitometry (TDM) in 55 hypercalciuric individuals in two separate studies. In the first, in a department of nephrology, 29 lithiasis patients were studied by TDM of L3. By this technique, trabecular density was 75 +/- 23% of normal. It was lower in the 17 patients in whom hypercalciuria persisted after calcium restriction (66 +/- 15% of normal and below the "fracture threshold" in 9 cases) than in the 12 patients in whom it disappeared after the prescription of such a diet (88 +/- 26%, below the "fracture threshold" in 3 cases), this difference being significant (p less than 0.01). In another 26 patients, seen in a department of rheumatology, three of whom had osteoporosis with vertebral fracture, density was measured in 21 cases by double photon absorptiometry (mean Z score -1.9 +/- 1.0) and in 5 cases by TDM (mean BMD of L3 69 +/- 21% of normal). Mean iliac trabecular volume, measured in 8 cases only, was 70 +/- 25% of normal and was below the "fracture threshold" in 3 cases. Comparison of the two study groups was not possible because of differences in recruitment and methods of investigation. These two studies nevertheless show the existence of significant vertebral bone rarefaction during hypercalciuria in the young man. Confirmed and quantified in patients in whom the metabolic disturbance was discovered as a result of radiological abnormalities, this quantitative abnormality was also seen in patients in whom hypercalciurie was found because of renal lithiasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗