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S Boonen

Publications and source records attributed to S Boonen.

At least 19 recordsLinked to original sources

The estrogen receptor ligand ICI 182,780 does not impair the bone-sparing effects of testosterone in the young orchidectomized rat model.

Testosterone (T) can affect bone metabolism not only directly, but also via its metabolites, estrogen or dihydrotestosterone, produced by enzymes present in bone. Therefore, the aim of this study was to investigate whether the high-affinity estrogen receptor ligand ICI 182,780 (ICI) impaired the bone-protective action of T in 3-month-old orchidectomized (Orch) rats, studied during an experimental period of 3 months. As expected, Orch significantly decreased trabecular bone volume in the proximal tibial metaphysis (-52%), as measured by histomorphometry, and had a similar negative effect on volumetric bone mineral density (BMD) in the distal femoral metaphysis (-53%), as assessed by peripheral quantitative computed tomography (pQCT). The loss of bone induced by Orch was completely prevented by T administration. Moreover, the Orch-associated increases of biochemical markers of bone turnover (serum osteocalcin, urinary deoxypyridinoline, and calcium excretion) did not occur when Orch rats received T. Administration of ICI in combination with T did not impair this bone-sparing effect. Cortical bone parameters (as determined by pQCT), body weight gain, and body composition (as measured by dual-energy X-ray absorptiometry) were not affected by T or ICI in combination with T. Furthermore, no differences were observed in serum concentrations of insulin-like growth factor-I or glucose homeostasis. In conclusion, ICI does not impair the long-term bone-protective effects of T in orchidectomized male rats, suggesting that testosterone can mediate its effect on the male skeleton directly via the androgen receptor. The absence of effects on body growth via the growth hormone--insulin-like growth factor-I axis may be a possible explanation for the lack of skeletal effects of this selective estrogen receptor antagonist.

Animals↗

Testosterone prevents orchidectomy-induced bone loss in estrogen receptor-alpha knockout mice.

To examine the role of the estrogen receptor-alpha (ERalpha) during male skeletal development, bone density and structure of aged ERalphaKO mice and wild-type (WT) littermates were analyzed and skeletal changes in response to sex steroid deficiency and replacement were also studied. In comparison to WT, ERalphaKO mice had smaller and thinner bones, arguing for a direct role of ERalpha to obtain full skeletal size in male mice. However, male ERalphaKO mice had significantly more trabecular bone as assessed both by pQCT and histomorphometry, indicating that ERalpha is not essential to maintain cancellous bone mass. Six weeks following orchidectomy (ORX), both WT and ERalphaKO mice showed high-turnover osteoporosis as revealed by increases in serum osteocalcin and decreases in trabecular (-38% and -58% in WT and ERalphaKO, respectively) and cortical bone density (-5% and -4% in WT and ERalphaKO, respectively). Administration of testosterone propionate (T, 5 mg/kg/day) completely prevented bone loss both in ERalphaKO and in WT mice. As expected, estradiol (E2, 60 microg/kg/day) replacement did not prevent cancellous bone loss in ORX ERalphaKO mice. However, E2 stimulated bone formation at the endocortical surface in ORX ERalphaKO, suggesting that osteoblasts may respond to nonERalpha-mediated estrogen action. In conclusion, although functional ERalpha may play a significant role during male skeletal development, this receptor does not seem essential for androgen-mediated skeletal maintenance in older male mice.

Animals↗

Quantitative ultrasound and trabecular architecture in the human calcaneus.

Relationships between quantitative ultrasound (QUS), density (bone volume density [BV/TV]), and trabecular architecture were investigated in 69 calcaneal cancellous bone cubes. Ultrasound signal velocity, phase velocity, attenuation, and broadband ultrasonic attenuation (BUA) measurements were made along the mediolateral axis. Density and architectural parameters were measured using microcomputed tomography (microCT). Density yielded the best correlations with QUS (r2 = 73-77%). Of the individual architectural parameters, correlations with QUS were highest for the Structure Model Index (SMI), a parameter quantifying the relative proportion of rods and plates (r2 = 57-63%). After adjustment for density, significant associations with QUS remained for SMI, trabecular spacing (Tb.Sp), and trabecular number (Tb.N), although the variance in QUS attributable uniquely to individual architectural parameters was at best 4%. In multivariate regression models, combinations of density and architectural parameters explained 76-82% of the variance in QUS, representing an r2 increase of, at most, 8% compared with using density alone. However, multivariate models using combinations of architectural parameters alone (i.e., density excluded) also had a good predictive ability for QUS (r2 = 73-81%). Thus, although these data show modest but significant density-independent relationships between QUS and trabecular architecture in the human calcaneus for the first time, the causal relationships behind the variation in acoustic properties remain obscure. Given the relative weakness and complexity of the emerging associations between QUS and architecture, it is prudent to regard QUS measurements in calcaneal bone primarily as an indicator of bone density.

Adult↗

The economic cost of hip fractures among elderly women. A one-year, prospective, observational cohort study with matched-pair analysis. Belgian Hip Fracture Study Group.

BACKGROUND: We conducted a prospective study to assess the costs of initial hospitalization for a first hip fracture and to evaluate the excess costs attributable to the hip fracture during the one-year period following hospital discharge. METHODS: This investigation was designed as a one-year prospective cohort study with matched-pair analysis. Elderly women who were receiving care for a first hip fracture at four Belgian hospitals were matched, with respect to age and residence, with women (control subjects) with no history of hip fracture who lived in the same neighborhood. The initial hospitalization costs were tabulated from the hospital invoices. To estimate the costs during the year after hospital discharge, health-care services utilized by the hip-fracture patients and by the control subjects were recorded. We used the official reimbursement rates to assign a cost to these services, and the results are reported in United States dollars. RESULTS: The mean age of the 159 patients who had a hip fracture was 79.3 years, and that of the 159 control subjects was 78.7 years. The total mean cost of the initial hospitalization was $9534 for the hip-fracture patients. The total direct costs during the year after discharge averaged $13,470 for the hip-fracture patients and $6170 for the control subjects. Thus, the excess direct cost during the one-year period following hospital discharge averaged $7300 for the hip-fracture patients. The largest cost differences were attributable to nursing-home stays (31%), rehabilitation-center stays (31%), hospitalizations (16%), and home physical-therapy services (14%). Two-fifths of the excess costs were spent during the three months following hospital discharge. Moreover, we observed a shift in resource utilization after hospital discharge. CONCLUSIONS: Our one-year prospective study demonstrated that the costs of treating a hip-fracture patient are about three times greater than those of caring for a patient without a fracture. This study also highlights the savings to society if a hip fracture can be avoided.

Aftercare↗

Primary hyperparathyroidism: pathophysiology, diagnosis and indications for surgery.

There is little debate about the primacy of surgery in the management of symptomatic or complicated primary hyperparathyroidism. Rather, the question has been what to do about the many patients with nonclassical disease. Recent prospective data have confirmed that patients with asymptomatic primary hyperparathyroidism who are not surgical candidates for parathyroidectomy appear to do well when they are managed conservatively. On average, these patients remain stable, with little progression to the more serious manifestations of hyperparathyroidism over 10 years. It would seem, therefore, that the overall population of older patients with mild asymptomatic primary hyperparathyroidism can be safely followed without intervention. A certain proportion of cases do progress, however, so surveillance is necessary. Individual patients can have worsening hypercalcemia or hypercalciuria, and in a small percentage of patients, bone density may decrease over time. In most patients, deferral of surgery is not a one-time decision, but rather one that is reviewed and reconsidered in conjunction with meticulous monitoring.

Bone Density↗

Polymorphisms of the VDR, ER and COLIA1 genes and osteoporotic hip fracture in elderly postmenopausal women.

In view of the reported associations between osteoporosis and polymorphisms of the vitamin D receptor (VDR), collagen Ialpha1 (COLIA1) and estrogen receptor (ER) genes, an association study was performed between VDR, COLLIA1, and ER genotypes and bone mineral density, biochemical markers of bone turnover and hip fracture occurrence in Belgian older postmenopausal women. The gene polymorphisms were evaluated by restriction fragment length polymorphism analyses, using the restriction enzymes BsmI (VDR), AccB7I (COLIA1), and PvuII and XbaI (ER), respectively. As expected, bone mineral density and biochemical analyses demonstrated significant differences between hip fracture patients and elderly controls. However, no significant differences in genotype distributions or allele frequencies were observed between the cases (n = 135, age 78 +/- 9 years) and controls (n = 239, age 76 +/- 4 years) for any of the gene polymorphisms. Stratification of both study populations according to VDR, COLIA1 or ER genotype did not reveal any statistically significant difference in bone density or bone turnover between subgroups with different genotypes. In conclusion, despite its limited statistical power the outcome of this study does not support the hypothesis of a major contribution of the VDR, COLIA1 or ER polymorphisms to explain variations in bone mineral density or bone turnover, or to identify elderly women at risk of osteoporotic hip fracture.

Aged↗

Costs induced by hip fractures: a prospective controlled study in Belgium. Belgian Hip Fracture Study Group.

The economic burden of hip fractures is thought to be important, but the excess medical costs they induce remain largely unknown. We assessed the direct medical costs induced by hip fractures during and after hospitalization. Hospital costs of 170 consecutive Belgian women with hip fracture were gathered. During the year following discharge, all medical costs were collected for the 159 hip fracture women who survived the acute hospitalization stay. A similar collection of data was performed on a comparison group of 159 age-and residence-matched women without a history of hip fracture. The mean cost of the acute hospital stay was 8,667 Belgian francs and the mean 1-year hip-fracture-related extra costs after hospitalization was 6,636 Belgian francs. During the year following the acute hospital stay, 19% of the hip fracture women and 4% of the comparison women were newly admitted to nursing homes (p<0.001). Although health care costs increased with age, hip-fracture-related extra costs after hospitalization seemed similar in those below or above 81 years old. These extra costs amounted to 7,710 Belgian francs in women not living in nursing homes at the time of fracture, and to 3,479 Belgian francs in women who lived in nursing homes. Health or mental status before hip fracture seemed not to affect extra costs. Taking into account the higher mortality of women with hip fracture, the extra costs during the acute hospital stay and during the 1-year follow-up amounted to a mean 15,151 Belgian francs. In conclusion, both acute hospital stays and subsequent medical care contribute significantly to medical costs induced by hip fractures.

Age Factors↗

Skeletal effects of estrogen deficiency as induced by an aromatase inhibitor in an aged male rat model.

Aromatization of androgens into estrogens may be important for maintenance of the male skeleton. To address this hypothesis, we evaluated the skeletal effects of selective estrogen deficiency as induced by the aromatase inhibitor vorozole (Vor), with or without 17beta-estradiol (E(2)) administration (1.35 microg/day), in aged (12-month-old) male rats. A baseline group was killed at the start of the experiment (Base). The control group (Control), the group treated with vorozole alone (Vor), the group treated with E(2) alone (E(2)), or the group with a combination of both (Vor + E(2)) were killed 15 weeks later. Vorozole significantly increased serum testosterone (T) and reduced serum E(2) compared with Control. Body weight gain and serum insulin-like growth factor-I (IGF-I) were also lower in Vor, whereas significant weight loss and decrease of serum IGF-I occurred as a result of E(2) administration. Bone formation as assessed by serum osteocalcin was unaffected but osteoid surface in the proximal metaphysis of the tibia was increased in Vor-treated rats. Bone resorption as evaluated by urinary deoxypyridinoline excretion was increased in Vor. Biochemical parameters of bone turnover were reduced significantly in all E(2) treated rats. Premature closure of the growth plates and decreased osteoid and mineralizing surfaces were also observed in E(2) and Vor + E(2). Apparent bone density of lumbar vertebrae and femur, as measured by dual-energy X-ray absorptiometry (DXA), was significantly reduced in Vor. Vorozole decreased femoral bone density mainly in the distal femur (trabecular and cortical region). This decrease of bone density was not present in E(2) and Vor + E(2). Similar findings were observed when bone density was assessed by peripheral quantitative computed tomography (pQCT); that is, trabecular density of the distal femur, the proximal tibia, and the distal lumbar vertebra were all lower in Vor. This decrease in density was not observed in all E(2)-treated animals. In conclusion, administration of the aromatase inhibitor, vorozole, to aged male rats induces net trabecular bone loss in both the appendicular and axial skeleton, despite a concomitant increase in serum testosterone. E(2) administration is able to prevent this trabecular bone loss in vorozole-treated animals.

Aging↗

Osteoporosis and osteoporotic fractures in men: a clinical perspective.

The lifetime risk of any fracture of the hip, spine or distal forearm in men aged 50 years has been estimated to be 13%, compared with 40% in women. Although the overall incidence of osteoporosis is less in men than in women, the disease still represents an important public health problem. In particular, hip fractures are associated with substantial mortality and morbidity, even more so than in women. In male patients presenting with osteoporotic fractures, major causes of skeletal fragility, such as hypogonadism, glucocorticoid excess, primary hyperparathyroidism and alcohol abuse, can often be identified. In as many as 50% of osteoporotic men, however, no aetiology can be found: these men suffer from a syndrome commonly referred to as idiopathic osteoporosis, which is presumably related to some type of osteoblast dysfunction. Recent evidence indicates that the loss of skeletal integrity in ageing men may be partially related to endocrine deficiencies, including vitamin D, androgen and/or oestrogen deficiency. While the consequences of vitamin D or oestrogen deficiency in women have been well established, the skeletal impact of these (partial) age-related deficiencies in men remains to be clarified. Osteoporosis in elderly men is a multifactorial disease, as it is in women. The prevention of osteoporosis should therefore focus not only on increasing the bone strength, but also on decreasing the risk of falls. However, the prevention and therapy of osteoporotic disorders in men are virtually unexplored. To date, the use of specific osteoporotic drugs in osteoporotic men is still based on reasonable but untested assumptions.

Endocrine System Diseases↗

An aged rat model of partial androgen deficiency: prevention of both loss of bone and lean body mass by low-dose androgen replacement.

The aim of this study was to evaluate the effects of different doses of androgen replacement, both on body composition and bone, in an aged male orchidectomized rat model. Testosterone was administered by 0.5, 1, and 2.5-cm sc SILASTIC implants (release of, respectively, 11.5, 23, and 55 microg/day) to aged (12 months old, +/- 550 g) male orchidectomized Wistar rats during a 15-week experimental period. T 0.5 only partially prevented decrease of ventral prostate and seminal vesicle weight, compared with an intact group that received an empty implant (Intact). The 1-cm implant (T 1) completely prevented decrease of both seminal vesicles and ventral prostate weight. The 2.5-cm implant (T 2.5) was clearly supraphysiological, as demonstrated by significant hypertrophy of both androgen-sensitive organs. Serum testosterone was lower in T 0.5 and T 1 (0.38 +/- 0.06 ng/ml and 0.92 +/- 0.06 ng/ml, respectively) and higher in T 2.5 (2.4 +/- 0.28. ng/ml), compared with both Intact (1.6 +/- 0.23 ng/ml) and the baseline group(1.6 +/- 0.11 ng/ml). As expected, orchidectomized rats that received an empty SILASTIC implant had significantly lower bone mineral content (-7.9%), apparent density (-5.7%), and lean body mass (-10.8%), as measured by dual-energy x-ray absorptiometry, without significant changes in body weight and fat mass, compared with Intact. Also, cancellous (-50.3%) and cortical (-1.8%) volumetric density, as measured by peripheral quantitative computed tomography, were decreased in the tibia. Bone turnover, as measured by serum osteocalcin and urinary deoxypyridinoline excretion, was increased in orchidectomized rats that received an empty SILASTIC implant. T 0.5 prevented all changes, not only in bone mineral content, density, and turnover but also in lean body mass. Moreover, there were no significant differences, for all these parameters, between the different doses of testosterone replacement. In conclusion, low-dose androgen replacement does not lead to lower bone mineral density, higher bone turnover, and lower lean body mass in aged male rats, whereas complete androgen deficiency does. Therefore, the threshold concentration of testosterone necessary for prevention of both bone and lean body mass loss in aged male rats is clearly lower than for prostate and seminal vesicles.

Aging↗

[Involutional osteoporosis in women: therapeutic strategy. Recommendations of the Belgian Bone Club].

Osteoporosis is now considered as a major public health issue and a serious threat for the quality of life of elderly women. Several new compounds are currently marketed for the prevention and treatment of involutional osteoporosis in women. Therefore, it is important to offer to the practitioners pragmatic solutions to be used for the rational management of this disorder. This article is the result of a national consensus offering practical guidelines for the management of osteoporotic patients, based on the current published data.

Estrogen Antagonists↗

The effect of modifying dietary calcium intake pattern on the circadian rhythm of bone resorption.

In order to assess day-to-day variations of the circadian rhythm of biochemical bone resorption markers, urinary morning (6-8 a.m.) and evening (7-10 p.m.) samples from 35 individuals were monitored during 3 subsequent days. The bone-specific deoxypyridinoline (DPD) crosslinks of type I collagen followed a circadian rhythm in all individuals. In contrast, no such pattern was observed in the urinary hydroxyproline/creatinine and calcium/creatinine measurements. The DPD crosslink measurements showed a much larger difference between the morning and evening samples collected within 1 day compared with the variation between the samples collected in the morning or evening on subsequent days, indicating the importance of adequate timing of urine sampling for clinical trials aiming to monitor effects on bone resorption. The analysis of DPD crosslinks was then used to evaluate the effects of different patterns of dietary calcium intake on the circadian rhythm of bone resorption in osteoporotic patients. No significant effect on the circadian rhythm of the DPD crosslinks was found after concentrating the normal daily calcium intake to the evening (6-10 p.m.) during 8 days (n = 7). Ingestion of a dietary calcium supplement (600 mg) at 10 p.m. during 8 days (n = 7) resulted in an increased urinary calcium excretion in the morning, and a flattening of the circadian peak and nadir concentrations of urinary DPD/creatinine. The absolute levels of DPD/creatinine in the morning and evening urine samples, respectively, were not significantly altered compared with the control day. We conclude that dietary calcium supplementation in the evening only marginally affects the circadian rhythm of urinary DPD crosslinks in established osteoporosis patients.

Aged↗

Upper and lower gastrointestinal evaluation of elderly inpatients who are iron deficient.

PURPOSE: Iron deficiency anemia is commonly caused by chronic gastrointestinal blood loss, and a thorough examination of the gastrointestinal tract has become standard practice. In contrast, iron deficiency without anemia has hardly been studied, and its causes are less certain. The aim of the present study was to determine the diagnostic value of upper and lower gastrointestinal evaluation in elderly hospitalized patients with iron deficiency, irrespective of the hemoglobin level. PATIENTS AND METHODS: In a prospective study, 151 consecutive elderly patients with iron deficiency (serum ferritin level < 50 microg/L at two separate occasions) were investigated using esophagogastroduodenoscopy with colonoscopy (n = 90) or barium enema (n = 61). RESULTS: A potential upper gastrointestinal tract lesion was found in 47 (49%) of the 96 anemic patients and in 31 (56%) of the 55 nonanemic patients (P = 0.38). Nonanemic patients had a greater prevalence of erosive gastritis or duodenitis. Anemic patients (72%) were more frequently investigated with a colonoscopy than nonanemic patients (38%, P = 0.001), and a lower gastrointestinal lesion was found in 32% of the anemic patients and 16% of the nonanemic patients (P = 0.03). Cancer was the most common lesion in the colon; 11 of the 18 patients were asymptomatic. Site-specific symptoms, fecal occult blood loss, and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) were not associated with the detection of gastrointestinal lesions. In 9.5% of the patients with a benign upper gastrointestinal lesion, a synchronous colonic tumor was found. CONCLUSION: Elderly patients with iron deficiency should undergo endoscopic examination, irrespective of the hemoglobin level. The presence of gastrointestinal symptoms, a positive fecal occult blood test, and the use of NSAIDs are of limited value in guiding the diagnostic procedure.

Aged↗

Down-regulation of the serum stimulatory components of the insulin-like growth factor (IGF) system (IGF-I, IGF-II, IGF binding protein [BP]-3, and IGFBP-5) in age-related (type II) femoral neck osteoporosis.

Both a decrease in bone formation and an increase in bone resorption have been implicated in the pathogenesis of age-related (type II) femoral neck osteoporosis. While the increase in the bone resorption rate has been shown to be partially related to secondary hyperparathyroidism, the mechanisms underlying the decline in bone formation have not yet been identified. The aim of the present study was to test the hypothesis that the bone formation deficit associated with type II osteoporosis might be due to secondary hyperparathyroidism and/or to a deficiency of the insulin-like growth factor (IGF) system. Circulating concentrations of IGF-I, IGF-II, IGF binding protein (IGFBP)-3, IGFBP-4, IGFBP-5, 25-hydroxycholecalciferol (25(OH)D3), and intact parathyroid hormone (PTH) were measured in 50 elderly women after sustaining a hip fracture and in 50 healthy age-matched controls. In addition, serum levels of osteocalcin (OC), skeletal alkaline phosphatase, and N-terminal procollagen peptide and urinary pyridinium cross-links were determined as markers of bone remodeling, and bone mineral density (BMD) was assessed at the proximal femur. In the patient group, serum was drawn within 18 h of the fracture and prior to surgery. Circulating protein concentrations did not change over this time frame. No difference was found between mean IGFBP-4 serum levels in the two groups studied, while mean levels of IGF-I, IGF-II, IGFBP-3, IGFBP-5, 25(OH)D3, and markers of bone formation were significantly lower (p < 0.006) in patients as compared with healthy subjects. Serum PTH and urinary pyridinium cross-links, however, were markedly increased (p < 0.001) in the osteoporotic group. In pooled data from the normal and osteoporotic populations, age-adjusted multiple regression models based on IGF-I, IGF-II, IGFBP-3, and IGFBP-5 were found to be highly predictive of serum OC (R2 = 19%, p < 0.001) and BMD of femoral neck (R2 = 49%, p < 0.0001), consistent with an effect of the anabolic IGF components on overall bone formation rate. Similar models based on 25(OH)D3 and PTH, however, were statistically unrelated to OC. To address further the potential impact of trauma on circulating IGF system components, we measured IGF system component levels in 10 male patients within 18 h following tibial fracture and in 10 age-matched normal male subjects. There was no significant difference in serum level of any of the IGF system components between the two groups. Although limited by its cross-sectional design, the present study suggests that, in addition to bone resorption resulting from secondary hyperparathyroidism, impaired bone formation associated with deficiency of the IGF system might predispose elderly women to fragility fracture of the proximal femur.

Age Factors↗

Lack of association between estrogen receptor genotypes and bone mineral density, fracture history, or muscle strength in elderly women.

The PvuII polymorphism of the estrogen receptor (ESR) gene and its relation to bone mineral density (BMD), fracture history, and muscle strength was studied in 313 postmenopausal (76 +/- 5 years) women of Caucasian origin, of whom 142 had suffered from a fragility fracture after the age of 50 years (14 with fracture of the hip, 38 of the spine, 45 of the wrist, and 85 of other bones). The ESR genotype distribution was similar in women with and without a history of fragility fracture (PP 21%, Pp 43%, pp 36% compared with PP 18%, Pp 47%, pp 35%). We did not find a correlation between the ESR genotypes and BMD at the lumbar spine, the femoral neck, or the proximal forearm. No association was found with grip or quadriceps strength. We further evaluated the relationship between the vitamin D receptor (VDR) and ESR haplotypes and BMD in a random subgroup of 270 elderly women. No differences were found in women with the BBpp versus the bbPP haplotype in the femoral neck (mean difference +/- SD, in Bbpp compared with bbPP groups: -0.05 +/- 0.15 g/cm2), the spine (0.01 +/- 0.13 g/cm2), or the forearm (0.04 +/- 0.08 g/cm2). The significant association of quadriceps strength with VDR genotypes (25% lower in BB compared with bb genotype, p < 0.05) was not influenced by ESR haplotypes. We conclude that in elderly Caucasian women the PvuII ESR polymorphism is not associated with osteoporosis, fracture history, nor muscle strength and does not influence the association of bone density and muscle strength with polymorphism of the VDR.

Aged↗

Factors associated with hip fracture occurrence in old age. Implications in the postsurgical management.

Fractures of the proximal femur (intracapsular as well as trochanteric fractures) are the most devastating complication of osteoporosis. These fractures are not only associated with significant morbidity, but also with a severe risk of death (+/- 25%) within one year. The strongest predisposing factor for fractures of the proximal femur is low bone density. In addition, numerous studies provide evidence that several other factors, independently, contribute to hip fracture risk, including low body mass index, previous fractures, muscle weakness, impaired vision, cognitive impairment, history of hyperthyroidism, use of long-acting sedatives, and physical inactivity. These findings indicate the need for preventive strategies based on risk factor modification and also on measures to maintain bone density. In view of the growing incidence of subsequent fracture of the contralateral hip, preventive strategies should be initiated in all these patients as an integral part of the postsurgical management during the acute hospital stay. These strategies should not only include combined supplements of calcium and vitamin D to attenuate further bone loss, but also a comprehensive assessment of risk factors.

Aged↗

Lack of association between osteoarthritis of the hip and gene polymorphisms of VDR, COL1A1, and COL2A1 in postmenopausal women.

OBJECTIVE: To evaluate whether DNA polymorphisms of the VDR (vitamin D receptor), COL1A1 (alpha1 type I collagen), and COL2A1 (alpha1 type II collagen) genes, which have previously been linked to bone mineral density (BMD) and/or osteoarthritis (OA), are also associated with OA of the hip (OAH). METHODS: Genotype frequency distributions were compared between a group of 239 elderly healthy female controls and a group of 75 female OAH patients who underwent total hip replacement. All participants underwent BMD measurements of the total body, lumbar spine, and femoral neck. Mutation detection was done using polymerase chain reaction followed by restriction enzyme digestion. Polymorphisms were detected by digestion with Bsm I for VDR, Acc B7I for COL1A1, and Pvu II for COL2A1. RESULTS: None of the genotype frequency distributions of any of the examined polymorphisms was significantly different between the OAH group and the control group. No significant differences in BMD variables were observed after stratification of the subjects according to the examined genotypes within each study group. CONCLUSION: In Belgian postmenopausal women, the examined polymorphisms of the candidate genes VDR, COL1A1, and COL2A1 do not significantly contribute to an increased prevalence of OAH or to differences in BMD.

Aged↗

Measurements of vertebral shape by radiographic morphometry: sex differences and relationships with vertebral level and lumbar lordosis.

OBJECTIVE: To examine sex-related and vertebral-level-specific differences in vertebral shape and to investigate the relationships between the lumbar lordosis angle and vertebral morphology. DESIGN AND PATIENTS: Lateral thoracic and lumbar spine radiographs were obtained with a standardized protocol in 142 healthy men and 198 healthy women over 50 years old. Anterior (Ha), central (Hc) and posterior (Hp) heights of each vertebra from T4 to L4 were measured using a digitizing technique, and the Ha/Hp and Hc/Hp ratios were calculated. The lumbar lordosis angle was measured on the lateral lumbar spine radiographs. RESULTS: Ha/Hp and Hc/Hp ratios were smaller in men than women by 1.8% and 0.7%, respectively, and these ratios varied with vertebral level. Significant correlations were found between vertebral shape and the lumbar lordosis angle. CONCLUSIONS: These results demonstrate that vertebral shape varies significantly with sex, vertebral level and lumbar lordosis angle. Awareness of these relationships may help prevent misdiagnosis in clinical vertebral morphometry.

Aged↗