Bone mineral density and vertebral compression fracture rates in ankylosing spondylitis.

OBJECTIVE--To examine the relationship between disease severity and bone density as well as vertebral fracture risk in patients with ankylosing spondylitis (AS). METHODS--Measurements were taken for bone mineral density (BMD) and vertebral fracture rates in 87 patients with AS. BMD was measured at the hip (femoral neck -FN), lumbar spine (L1-L4-LS) and for the whole body using a hologic-QDR-1000/W absorptiometer. An algorithm based on normal female ranges of vertebral heights was used to define a fracture as occurring when two vertebral ratios were each three standard deviations below the calculated mean of the controls. RESULTS--Patients with AS had significantly lower FN-BMD in proportion to disease severity (based on a Schober index) and disease duration. LS-BMD was also reduced in early disease, but in patients with advanced AS it had increased considerably. Nine vertebral fractures (10.3%) were identified which was considerably higher than expected when compared with a fracture of 1.9% in a control population of 1035 females of a similar age range. Patients with AS with fractures were significantly older, more likely to be male, had longer disease duration and more advanced spinal limitation with less mobility. There was no significant reduction in lumbar spine or femoral neck bone density in the fracture group. CONCLUSIONS--Vertebral fractures that result from osteoporosis are a feature of longstanding AS. BMD used as a measure of osteoporosis of the spine in advanced AS is unreliable probably as a result of syndesmophyte formation and does not predict the risk of vertebral fracture. Alternative sites such as the neck of the femur should be used for sequential assessment of BMD in AS.     

How should clinicians manage osteoporosis in ankylosing spondylitis?

Osteoporosis is a common complication of AS, with an incidence between 18.7% and 62%. The prevalence of osteoporosis is greater in males, and increases with increasing patient age and disease duration. Osteoporosis is also more common in patients with syndesmophytes, cervical fusion, and peripheral joint involvement. These variables are not all independent, as they may be indicators of disease duration. Osteoporosis in patients with AS is largely confined to the axial skeleton, in contrast to the pattern of osteoporosis seen in rheumatoid arthritis. BMD at the lumbar spine and femoral neck may be severely reduced, while most studies indicate that carpal and radial BMD remain within normal limits. The development of syndesmophytes in late AS can lead to difficulties in the use of DEXA scanning to determine lumbar BMD, as the extraspinal bone may obscure osteoporotic vertebrae. Under these circumstances more accurate assessment of lumbar BMD, and one that correlates better with femoral neck BMD, may be obtained by quantitative CT scanning or DEXA scanning of the lateral aspect of the L3 vertebra. Osteoporosis in AS significantly increases the risk of vertebral compression fractures within 5 years of the diagnosis of AS. The risk of a vertebral compression fracture occurring over a 30 year period following the diagnosis of AS is 14%, compared to 3.4% for population controls. In patients with vertebral osteoporosis relatively minor trauma, such as slipping, can lead to spinal fracture and dislocatior with subsequent damage to the spinal cord. There is a higher incidence of spinal cord injury following spinal fracture dislocations in patients with AS, and the resulting neurological deficit can range from mild sensory loss to complete paraplegia. Cytokines such as TNF-alpha and IL-6 may play an important part in the pathogenesis of osteoporosis in early AS, and IL-6 levels have been correlated with markers of disease activity and severity. In late AS, mechanical factors such as decreased mobility and the support provided by extraspinal bone may play a role in vertebral osteoporosis. Screening patients with AS for the presence of osteoporosis is an important, but contentious subject. This and subsequent monitoring needs to be considered in all patients, but longterm studies are needed to determine with confidence which patients should undergo screening, by which methods, and how often. The treatment of osteoporosis in AS is at present similar to that used for primary osteoporosis, except that due to the male predominance and a relatively young age of patients, there is a limited role for hormone replacement therapy. Exercise regimens and bisphosphonates are widely used, but a study of the relative efficacy of different bisphosphonate agents in patients with AS is required.     

The prevalence of vertebral fractures in mild ankylosing spondylitis and their relationship to bone mineral density

OBJECTIVE: To determine bone mineral density (BMD) in patients with mild ankylosing spondylitis (AS), to establish the prevalence of vertebral fractures and fracture risk in these patients, and to determine the relationship between BMD and vertebral fractures. METHODS: Sixty-six men with mild AS were studied. BMD of the lumbar spine and femoral neck was measured by dual X-ray absorptiometry (DXA) and radiographs of the thoracic and lumbar spine were obtained in all subjects. From the radiographs, vertebral fractures were characterized by a morphometric technique using established criteria. Thirty-nine healthy male subjects aged 50-60 yr, recruited from primary care registers, had spinal radiographs performed and served as controls for vertebral fractures. RESULTS: In patients with AS, BMD was reduced in both the lumbar spine 0.97 (0.1) g/cm(2) [T score -1.10 (1.3), 95% confidence interval (CI) -0.50, +0.14] and femoral neck 0.82 (0.1) g/cm(2) [T score -1.40 (1.2), 95% CI -0.51, +0.09]. There was no correlation between BMD of either the lumbar spine or femoral neck and duration of disease in patients with AS. Eleven of 66 (16.7%) patients with AS had a vertebral fracture, compared with one of 39 (2.6%) controls; odds ratio 5.92 (95% CI 1.4, 23.8). AS patients with fractures were not significantly older (mean age 41.4 vs 37.8 yr, P=0.17), but had significantly longer disease duration (12.4 vs 9.3 yr, P<0.05) than patients without fractures. No significant difference was found in the visual analogue scores for pain in AS patients with fractures compared with those without. No significant correlation was observed between BMD of the lumbar spine or femoral neck and vertebral fractures in patients with AS. In addition, there was no significant difference in the lumbar spine or femoral neck BMD in AS patients with fractures compared with those without. CONCLUSIONS: Spinal and hip osteopenia and vertebral fractures are a feature of mild AS. However, there was no correlation between BMD and vertebral fractures in these patients. AS patients with mild disease had a higher risk of fractures compared with the normal population and this increased with the duration of disease.     

经皮椎体增强术后生物力学有限元模型的建立及应用

目的建立腰2椎体骨质疏松致压缩骨折患者应用骨水泥注入治疗前后生物力学有限元模型,观察对比病椎与相邻椎体治疗前后应力的改变情况。方法随机选取本院1例70岁腰2椎体骨质疏松致压缩骨折经皮实施椎体成形术治疗患者,双侧腰2椎弓根予以少量骨水泥注入,2年后随访其病椎与相邻的椎体均未见新发骨折,并且局部无疼痛。参照治疗前后患者腰椎CT资料,建立三维生物力学有限元模型,并模拟患者腰椎旋转、屈伸及左右侧屈,观察对比病椎与相邻椎体治疗前后应力的改变情况。结果成功建立腰2椎体骨质疏松致压缩骨折予以少量骨水泥注入治疗前后的三维生物力学有限元模型。共计211618个单元生成,其中20914个4节点壳单元、190107个10节点体单元、597个杆单元。骨水泥注入后,腰2椎体的伸、屈及侧屈应力较前增加（P均〈0．05）,椎体旋转时应力治疗前后比较无统计学差异（P〉0．05）;腰1及腰3椎体伸、屈、旋转及侧屈时应力治疗前后无差异（P〉0．05）。结论生物力学有限元模型有助于腰椎骨质疏松致压缩骨折患者骨水泥治疗的预后判定。关键词：腰椎骨折;骨质疏松;骨水泥;生物力学;三维有限元     

Ankylosing spondylitis and osteoporosis

PURPOSE: Ankylosing Spondylitis (AS) is an inflammatory rheumatism characterized by its disease course with flares leading to progressive ankylosis of the spine related to paravertebral ligamentous and discal structures ossification. AS patients suffer significantly more vertebral fractures than control groups. These fractures could affect cervical spine. They are due to either ankylosis-related flawed spine compliance or AS-induced osteoporosis. CURRENT KNOWLEDGE AND KEY POINTS: The physiopathology of this osteoporosis is multi-factorial, but essentially linked to AS-related inflammatory phenomenons. It is marked by reduced bone density (at lumbar spine and femoral neck), increased bone turnover (with increased urinary C-telopeptide cross-linked collagen type 1), but without any significant change in phosphocalcic blood parameters. Histological features are depressed bone formation, with either maintained or increased resorption. FUTURE PROSPECTS: The screening of this osteoporosis is based upon investigating people at risk (progressive inflammatory AS) using dual-energy x-ray absorptiometry and biochemical markers of bone turnover. Treatment is based upon a modulation of both inflammatory phenomenons and bone remodelling using bisphosphonates and anti-TNF alpha.     

Ankylosing spondylitis and bone mineral density—what is the ideal tool for measurement?

Ankylosing spondylitis (AS) is characterised by chronic inflammation and partial ossification, yet vertebral fractures due to osteoporosis, although common, are frequently unrecognised. The aim of this study was to (1) show the frequency of changes in the progress of osteopenia/osteoporosis in AS depending on duration and stage of the disease and (2) assess the ranking of two different methods of bone density measurement in this clinical pattern. We measured bone density in 84 male and female patients with both dual X-ray absorptiometry (DXA) and single energy quantitative computed tomography (SE-QCT). In the initial and advanced stages of the disease, a high decrease in axial bone density could be verified (DXA: osteopenia in 5% and osteoporosis in 9.2%; SE-QCT: osteopenia in 11.8% and osteoporosis in 30.3%). Peripheral bone density decrease as in osteopenia could be proven in 17.6% by DXA measurement. With SE-QCT, a decrease in vertebral trabecular bone density could already be observed in the initial stage and continued steadily during the course of the disease; cortical bone displayed the same trend up to stages of ankylosis. With DXA, valid conclusions are more likely to be expected in less marked ankylosing stages of AS. In stages of advanced ankyloses in the vertebral region (substantial syndesmophytes), priority should be given to SE-QCT, due to the selective measurement of trabecular and cortical bone. The DXA method often yields values that are too high, and the replacement of vertebral trabecular bone by fatty bone marrow is not usually recorded as standard. There may already be an increased risk of bone fracture in AS in osteopenia on DXA along with an osteoporosis already established on SE-QCT.     

Appendicular and vertebral bone mass in ankylosing spondylitis. A comparison of plain radiographs with single- and dual-photon absorptiometry and with quantitative computed tomography.

OBJECTIVE. We assessed the prevalence, severity, and anatomic distribution of ankylosing spondylitis (AS)-related osteopenia (OP). METHODS. We studied 70 patients (60 males, 10 premenopausal females) with AS (according to the New York criteria) to determine the frequency of OP. Bone mass was measured by plain radiographs of the spine, by single-photon absorptiometry (SPA) of the distal and midshaft of the radius on the nondominant side, by dual-photon absorptiometry (DPA) of the lumbar spine (L2-L4), and by quantitative computed tomography (QCT) of the lumbar spine. RESULTS. SPA values for the radius mass were normal in males and in females, both at the distal and midshaft sites. In contrast, spine radiographs showed diminished density of the vertebral bodies in 69% of the males and 50% of the premenopausal females. Two male patients had had a vertebral compression fracture, and one female patient had had two. DPA values for the spine mass were significantly diminished in the male patients compared with the controls, but not in the female patients. Males with less severe AS also had the largest reduction in lumbar bone mineral content. In patients with more severe disease, lumbar bone mineral content was not statistically different from that in controls. QCT of the lumbar spine performed in 10 patients disclosed low density of the trabecular bone of the vertebral bodies, more so in those with more severe AS and syndesmophyte formation and/or apophyseal joint fusion, which contrasts with the normal values on DPA in these patients. CONCLUSION. Male patients with AS have axial osteopenia. In those who have very severe AS with new bone formation, DPA demonstrates normal values as a result of two opposite trends: central osteopenia (as assessed from QCT) and peripheral new-bone formation, which transforms vertebral bodies into long bones. This could modify the mechanical resistance of the spine and account for the propensity for anteroposterior transvertebral and transdiscal fractures after trauma in AS.     

Sustained-release sodium fluoride in the treatment of the elderly with established osteoporosis

BACKGROUND: We ascertained the safety and efficacy of fluoride in augmenting spinal bone mass and reducing spinal fractures in older women with established osteoporosis. We compared a combination of sustained-release sodium fluoride, calcium citrate, and cholecalciferol (SR-NaF group) with calcium and cholecalciferol alone (control group). METHODS: Eighty-five ambulatory women aged 65 years or older with 1 or more nontraumatic vertebral compression fractures were enrolled in a 42-month randomized, double-blind, placebo-controlled trial. Primary outcome measures were vertebral fracture rate, bone mass, and safety. RESULTS: The vertebral fracture rate determined by means of computer assistance in the SR-NaF group was significantly lower than that in the control group (relative risk [RR], 0.32; 95% confidence interval [CI], 0.14-0.73; P =.007). Results of visual adjudicated inspection also confirmed a significant reduction in fracture rate (RR, 0.40; 95% CI, 0.17-0.95; P =.04). Bone mineral density in L2 through L4 increased significantly from baseline in the SR-NaF group by 5.4% (95% CI, 2.7%-8.2%; P<.001), and by 3.2% in the control group (95% CI, 0.8%-5.6%; P =.01). The between-group differences in bone mineral density were not significant. The femoral neck and total hip bone mineral density remained stable in the SR-NaF group and was not significantly different from that of the control group. There were no significant differences in adverse effects between groups. CONCLUSION: The SR-NaF group significantly decreased the risk for vertebral fractures and increased spinal bone mass without reducing bone mass at the femoral neck and total hip.     

Osteoporosis in patients with inflammatory bowel disease.

Bone mineral content in spinal trabecular and peripheral cortical bone was measured in 75 unselected patients with small and/or large intestinal inflammatory bowel disease. Osteoporosis, defined as a bone mineral content greater than 2 SD below the age and sex matched normal mean value was present in 23 patients (30.6%). Three amenorrhoeic females aged 34, 38, and 42 years had severe clinical osteoporosis and a further three patients had one or more vertebral crush fractures. Eighteen of the 23 patients with osteoporosis had small intestinal disease with one or more resections and the mean lifetime steroid dose in those with osteoporosis was significantly higher than in those with normal bone mineral content. Bone mineral content in spinal trabecular bone showed significant negative correlations with lifetime steroid dose and serum alkaline phosphatase and a significant positive correlation with serum albumin. Peripheral cortical bone mineral content was positively correlated with body weight, height and body mass index. We conclude that the prevalence of osteoporosis is increased in patients with inflammatory bowel disease, severe clinical osteoporosis developing in some relatively young patients. The pathogenesis of this bone loss is probably multifactorial; steroid therapy is likely to be an important contributory factor.     

Spinal fractures in patients with ankylosing spondylitis

The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine.     

Male osteoporosis with vertebral fractures? Look for ankylosing spondylitis! A report of 10 cases

OBJECTIVE: Several authors have described the association of ankylosing spondylitis (AS) and osteoporosis. Usually vertebral fractures complicate severe AS. METHODS: We report a series of 10 men in whom benign spondyloarthropathy was discovered during etiological investigation for osteoporosis. Eight patients had B27+ AS and 2 had psoriatic arthritis with axial involvement. The mean number of vertebral fractures was 1.5. No patient had an appendicular fracture. RESULTS: Phosphorus and calcium levels and measurements of 25OHD3, parathyroid hormone, osteocalcin, and serum CTX were in the normal range. The decrease in bone mineral density was greater in the spine (mean T-score at L2-L4 -2.95, mean total hip T-score -1.67). CONCLUSION: Osteoporosis with fractures may reveal benign spondyloarthropathy whose clinical expression is sometimes incomplete. Our findings demonstrate that osteoporosis is not always correlated with the severity of AS.     

Appendicular and vertebral bone mass in ankylosing spondylitis. A comparison of plain radiographs with single- and dual-photon absorptiometry and with quantitative computed tomography

Objective. We assessed the prevalence, severity, and anatomic distribution of ankylosing spondylitis (AS)-related osteopenia (OP). Methods. We studied 70 patients (60 males, 10 premenopausal females) with AS (according to the New York criteria) to determine the frequency of OP. Bone mass was measured by plain radiographs of the spine, by single-photon absorptiometry (SPA) of the distal and midshaft of the radius on the nondominant side, by dual-photon absorptiometry (DPA) of the lumbar spine (L2-L4), and by quantitative computed tomography (QCT) of the lumbar spine. Results. SPA values for the radius mass were normal in males and in females, both at the distal and midshaft sites. In contrast, spine radiographs showed diminished density of the vertebral bodies in 69% of the males and 50% of the premenopausal females. Two male patients had had a vertebral compression fracture, and one female patient had had two. DPA values for the spine mass were significantly diminished in the male patients compared with the controls, but not in the female patients. Males with less severe AS also had the largest reduction in lumbar bone mineral content. In patients with more severe disease, lumbar bone mineral content was not statistically different from that in controls. QCT of the lumbar spine performed in 10 patients disclosed low density of the trabecular bone of the vertebral bodies, more so in those with more severe AS and syndesmophyte formation and/or apophyseal joint fusion, which contrasts with the normal values on DPA in these patients. Conclusion. Male patients with AS have axial osteopenia. In those who have very severe AS with new bone formation, DPA demonstrates normal values as a result of two opposite trends: central osteopenia (as assessed from QCT) and peripheral new-bone formation, which transforms vertebral bodies into long bones. This could modify the mechanical resistance of the spine and account for the propensity for anteroposterior transvertebral and transdiscal fractures after trauma in AS.     

A case of post-pregnancy osteoporosis combined with ankylosing spondylitis

Post-pregnancy osteoporosis is not a common disease and is hard to diagnosis because their specific situation is post-partum and lactation. It commonly occurs on lumbar spine within a few months after the birth of a patient’s first child and it could lead to be fracture after minor trauma. Although its etiology is not clear, it would not be of sufficient magnitude to cause fractures unless the woman already had a substantial decrease in bone mass. Also, it is rare to be combined with ankylosing spondylitis. Ankylosing spondylitis has a higher risk of osteoporosis and vertebral fracture which increased with the duration of disease. We report a case of post-pregnancy osteoporosis with multiple spinal compression fracture in association of ankylosing spondylitis.     

Body composition and skeletal metabolism following pituitary irradiation in acromegaly

The change in body composition in acromegaly that resulted from pituitary irradiation was examined using the technic of total body neutron activation analysis. Before treatment, increased ratios of total body P:Ca, P:K and Na:K were noted. After pituitary irradiation, the total body levels of P, Na and K were reduced in a proportion that indicated restoration of body composition towards normal. Skeletal mass (total body calcium) decreased into the range observed in osteoporosis in several patients. Trabecular bone mass, as reflected by the Singh Index, was consistently reduced, and two patients had vertebral compression fractures. Local bone mass as determined by photon absorptiometry was reduced when the values were normalized for age, sex and body size.It is postulated that in untreated acromegaly there is differential bone remodelling with an increase in cortical bone accompanied by a reduced trabecular bone mass. When reduction of hGH levels is accomplished with treatment, cortical apposition may decrease. Since the increased cortical bone mass probably aids in preventing vertebral compression fractures, the treated acromegalic patient may incur an increased risk of fractures. This risk may be increased further by the hypogonadism which may arise secondary to pituitary irradiation or surgery. It would be prudent to ensure that the hypogonadal acromegalic patient receives an adequate calcium intake and sex hormone replacement therapy.     

Biochemical markers of bone metabolism in mild ankylosing spondylitis and their relationship with bone mineral density and vertebral fractures.

OBJECTIVE: To determine the relationship of biochemical markers of bone metabolism in patients with mild ankylosing spondylitis (AS) with disease activity, bone mineral density (BMD), and vertebral fractures. METHODS: A total of 56 male patients with mild AS were studied. All patients had BMD measured by dual x-ray absorptiometry of the lumbar spine and hip and radiographs of the thoracic and lumbar spines. Radiographs of patients with AS were evaluated morphometrically and vertebral fractures were defined using established criteria. Serum osteocalcin, total and bone alkaline phosphatase (ALP, BALP, respectively), 25-hydroxyvitamin D (25-OHD), parathyroid hormone (PTH), urinary deoxypyridinoline (Dpyr), and pyridinoline (Pyr) were measured in the patients with AS and compared with 52 age and sex matched controls. Thirty-nine healthy male subjects aged 50-60 years, recruited from primary care registers, had spinal radiographs and served as controls for vertebral fractures. RESULTS: Patients with AS had reduced BMD of the lumbar spine, 0.98 (0.1) g/cm2 [T score = -1.14 (1.2) and Z score = -1.01 (1.2)], and femoral neck, 0.83 (0.1) g/cm2 [T score = -1.44 (1.2) and Z score = -0.73 (1.1)]. Of the 56 patients with AS, 11 (19.6%) had a vertebral fracture, whereas only one of 39 control subjects did (2.6%). Patients with AS had significantly lower mean serum osteocalcin compared with controls [9.03 (2.7) microg/l vs 11.05 (2.33) microg/l; p < 0.001], and significantly higher mean serum ALP [73.09 (19.5) U/l vs 53.02 (16.7) U/l; p < 0.001] and BALP [38.54 (9.9) U/l vs 30.35 (8.28) U/l; p < 0.001]. There was no significant difference in the excretion of Dpyr and Pyr between patients with AS and controls [4.90 (3.9) nmol/mmol vs 4.00 (3.6) nmol/mmol, and 15.66 (10.8) nmol/mmol vs 12.24 (10.3) nmol/mmol, respectively]. There were no significant differences in the mean 25-OHD and PTH levels in patients with AS compared to controls [20.03 (1.6) micromol/l vs 18.9 (2.9) micromol/l and 3.31 (1.5) pmol/l vs 2.63 (0.4) pmol/l, respectively]. The biochemical markers of bone formation and resorption correlated well with inflammatory indices of disease activity (acute phase reactants), but not with BMD of the lumbar spine or femoral neck. No significant difference was seen in any marker of bone turnover when AS patients with vertebral fractures were compared with those without. CONCLUSION: Bone turnover in patients with mild AS is characterized by low serum osteocalcin and ALP in the presence of normal calciotropic hormones. Biochemical markers of bone metabolism do not correlate with BMD or vertebral fractures. The disparity between osteocalcin and alkaline phosphatase in patients with AS needs further evaluation.     

绝经后妇女脊椎压缩性骨折与骨密度的关系

目的探讨绝经后妇女脊椎压缩性骨折与骨密度（BMD）的关系。方法为病例一对照研究，入选250例有脊椎压缩性骨折的绝经后妇女，另有250名无脊椎压缩性骨折的绝经后妇女作为对照组。两组均有胸腰椎正侧位X线摄片，并应用双能X线吸收仪检测腰椎1～4和左股骨近端各部位BMD。结果脊椎压缩性骨折组身高、体重、腰椎2～4和股骨近端各部位BMD值均显著低于对照组（均P〈0．01）。腰椎2～4BMD是发生脊柱骨折的预报因子（r=-0．416，P〈0．01）。身高和全髋部BMD与骨折次数和骨折椎体数目呈负相关（均P〈0．01）。按股骨颈和全髋部BMD值，骨折组骨质疏松检出率各为50．8％和50．4％；另外剔除在腰椎2～4发生椎体骨折53例，按腰椎2～4BMD检出骨质疏松占64．5％。同时，腰椎2～4、股骨颈或全髋部BMD值低于-2．5s者发生脊柱压缩性骨折的风险分别是BMD正常者的4．76、2．36和3．52倍。结论腰椎呈低骨量是发生脊椎压缩性骨折的重要危险因素。身高的下降和全髋部低BMD值是骨折发生次数和受累椎体数目的危险因子；对绝经后妇女在重视BMD测量的同时，应重视脊柱X线正侧位检查。     

Predictors of osteoporosis and vertebral fractures in patients presenting with moderate-to-severe chronic obstructive lung disease

Bone mineral density (BMD) alone does not reliably predict osteoporotic fractures. The Fracture Risk Assessment Tool (FRAX) was developed to estimate the risk of fracture in the general population. This study was designed to identify predictors of osteoporosis and vertebral fractures in patients presenting with chronic obstructive pulmonary disease (COPD). We studied 85 patients (mean age = 75 years; 92% men) with moderate to very severe COPD. Osteoporosis and vertebral fractures were diagnosed with dual energy X-ray absorptiometric scan and vertebral X-rays, respectively. Patient characteristics, including age, gender, body mass index (BMI), and results of pulmonary function tests, chest computed tomography scan, blood and urinary biomarkers of bone turnover were recorded, and a FRAX score was calculated by a computer-based algorithm. Osteoporosis, defined as a T score < -2.5, found in 20 patients (24%), was associated with female gender, BMI, dyspnea scale, long-term oxygen therapy (LTOT), vital capacity (VC), emphysema score on computed tomography, measurements of serum and urinary biomarkers of bone turnover. Vertebral fractures, diagnosed in 29 patients (35%), were strongly correlated with age, LTOT, VC, and forced expiratory volume in 1 sec, treatment with oral corticosteroid or warfarin, and weakly associated with the presence of osteoporosis. There was no correlation between FRAX score and prevalence of vertebral fractures, suggesting that neither BMD alone nor FRAX score would predict the presence of vertebral fractures in COPD patients. A disease-specific algorithm to predict osteoporotic fractures is needed to improve the management of patients suffering from COPD.     

Clinical characteristics and etiologic factors of premenopausal osteoporosis in a group of Spanish women

OBJECTIVES: To analyze the clinical characteristics and the principal causes of osteoporosis in premenopausal women. METHODS: This study included 52 osteoporotic premenopausal women ages 20-51 years (mean 36.2 +/- 7) who were referred to an outpatient rheumatology department for osteoporosis evaluation. Bone mass assessment, automated biochemical profile, urinary calcium excretion, and bone marker assays were performed on all patients. Hormonal measurements were made when a specific etiology was not readily apparent. The diagnosis of osteoporosis was defined by the presence of atraumatic vertebral fractures and/or by densitometric criteria. Previous skeletal fractures, weight, height, body mass index (BMI), age at menarche, and family history of osteoporosis also were recorded. RESULTS: Twenty-nine patients (56%) had idiopathic osteoporosis and 23 (44%) had secondary osteoporosis. Fifteen patients (29%) had vertebral fractures and 12 had previous peripheral fractures. Patients with secondary osteoporosis showed higher BMI (23.2 +/- 3 v 21.2 +/- 2, P =.02) and lower femoral Z-scores of bone mineral density (BMD) (-2.1 +/- 0.6 v -1.5 +/- 0.9, P =.02) than those with idiopathic disease. The most frequent causes of secondary osteoporosis included Cushing syndrome, pregnancy osteoporosis, and osteogenesis imperfecta. Nearly half of the patients (48%) with idiopathic osteoporosis had a family history of osteoporosis. In addition, 11 patients (38%) with idiopathic osteoporosis had associated hypercalciuria. Except for an increase in urinary calcium excretion (248 +/- 53 v 143 +/- 47 mg/24 h, P <.0001), no other significant differences in the remaining variables analyzed were found between hypercalciuric and normocalciuric patients with idiopathic osteoporosis. CONCLUSIONS: Idiopathic osteoporosis was the most frequent diagnosis of pre-menopausal osteoporosis in our unit. These patients showed lower BMI and higher femoral neck Z-scores than patients with secondary causes. A family history of osteoporosis and hypercalciuria were factors frequently associated with this disorder.     

Serum osteoprotegerin and its ligand in cirrhotic patients referred for orthotopic liver transplantation: relationship with metabolic bone disease.

AIMS: A prospective study was carried out in 22 cirrhotic patients referred for orthotopic liver transplantation, in order to analyze serum osteoprotegerin (OPG) and RANKL levels and their relationship with metabolic bone disease. METHODS: Serum levels of OPG and RANKL were measured in all patients as well as bone markers, serum parathyroid hormone and 25-hydroxyvitamin D levels. OPG and RANKL values were compared with those obtained in 29 healthy controls. Bone mineral density (BMD) of the lumbar spine and proximal femur was measured by dual X-ray absorptiometry and spinal X-rays were obtained to assess vertebral fractures. RESULTS: Serum OPG levels were higher in cirrhotic patients than in controls (6.4+/-2 vs 2.7+/-0.7 pmol/l; P=0.001) and RANKL serum levels were lower in cirrhotic patients (0.215+/-0.6 vs 1.012+/-1.2 pmol/l; P=0.002), with an increased OPG:RANKL ratio when compared with the control group (280.3+/-334.5 vs 113+/-137.6; P=0.04). Ten patients had osteoporosis (45%) and up to 45% skeletal fractures. No differences were found in OPG levels between patients with and without osteoporosis by densitometric criteria or fractures. Negative correlations were found between OPG levels and femoral neck (R-0.46; P=0.03) and total hip BMD (R-0.48; P=0.025). By contrast, OPG values were not related to markers of bone turnover. CONCLUSIONS: OPG values are elevated in cirrhotic patients before liver transplantation, particularly in those with low bone mass at the proximal femur.     

Bone loss is detected more frequently in patients with ankylosing spondylitis with syndesmophytes

OBJECTIVE: To define the relationship between bone growth (syndesmophytes) and bone loss (osteoporosis) in ankylosing spondylitis (AS). METHODS: Bone mineral density (BMD) at the spine, hip, and radius was measured by dual-energy x-ray absorptiometry (DEXA), dual-energy quantitative computed tomography (DEQCT), and peripheral quantitative computed tomography (pQCT) in 103 patients with AS. Radiographs of the lumbar spine were used to detect syndesmophytes. Patients were divided in 3 groups according to disease duration. RESULTS: Osteopenia at the hip and spine was found by DEXA in 56% and 41%, respectively, of the patients with disease duration < 5 years (n = 27), with an additional 11% and 15% having osteoporosis. In patients with a longer disease duration, > 10 years (n = 28), 29% were osteoporotic at the hip and only 4% at the lumbar spine. In contrast, using spinal DEQCT, 59% of patients with early disease were found to be osteopenic; 36% of patients with long-standing disease were osteopenic and 18% were osteoporotic. More than half the patients (55%) had syndesmophytes (n = 55). With spinal DEQCT there were more patients with syndesmophytes (63%) in the group with reduced bone density than in the group without (45%). This was similar with DEXA measurements at the hip, where 31% compared to 14% had osteoporosis, respectively. Osteocalcin was elevated in 34% of patients, but was not associated with disease activity or BMD. CONCLUSION: The majority of patients with AS had reduced bone density. The method of bone density measurement is critical and should be different depending on disease duration. The finding that more patients with syndesmophytes had reduced bone density than those without suggests that bone growth and bone loss occur in parallel, and the role of inflammation in this process warrants further investigation.