Quantitative Ultrasound and Symptomatic Vertebral Fracture Risk in Chinese Women

Quantitative ultrasound (QUS) is emerging as a simple, inexpensive and noninvasive method for assessing bone quality and assessing fracture risk. We assessed the usefulness of a contact calcaneal ultrasonometer by studying normal premenopausal women (group I, n= 53), normal postmenopausal women (group II, n= 198), and osteoporotic women without (group III, n= 141) and with vertebral fractures (group IV, n= 53). The osteoporotic subjects had a T-score of the spine or hip neck bone mineral density (BMD) <−2.5 based on the local Chinese peak young mean values. When compared with postmenopausal controls, mean broadband ultrasound attenuation (BUA), speed of sound (SOS), and quantitative ultrasound index (QUI) were 26%, 2.1% and 25% lower in women with vertebral fractures (p all <0.005). The correlation coefficients between QUS parameters and BMD of the spine and hip ranged between 0.4 and 0.5. The ability of the QUS to discriminate between patients groups was determined based on the mean value of normal premenopausal women in group I. The mean T-score for women with fractures was −2.87 ± 1.02 for BUA, −2.54 ± 0.79 for SOS, −3.17 ± 0.70 for QUI, −2.65 ± 0.86 for L2–4 BMD and −2.53 ± 0.66 for hip neck BMD. After adjustment for age and body mass index, the odds ratio of vertebral fracture was 1.71 (95% CI 1.2–2.6) for each 1 SD reduction in BUA, 2.72 (1.3–5.3) for SOS, 2.58 (1.4–4.6) for QUI, 2.33 (1.6–3.3) for L2–4 BMD, 2.09 (1.37–3.20) for femoral neck BMD and 1.88 (1.34–2.92) for total hip BMD. The association between the QUS parameters and vertebral fracture risk persisted even adjustment for BMD. The area under the receiver operating characteristic curve for BUA for vertebral fracture was 0.92, for SOS, QUI, L2–4 BMD and femoral neck BMD was 0.95, and for total hip was 0.91. Received: 7 January 1999 / Accepted: 18 May 1999     

Bone Mineral Density and Vertebral Fractures in Men

In women, many studies indicate that the risk of vertebral fragility fractures increases as bone mineral density (BMD) declines. In contrast, few studies are available for BMD and vertebral fractures in men. It is uncertain that the strength of the relationship between BMD and fractures is similar in magnitude in middle-aged men and in postmenopausal women. In the present study, 200 men (mean age 54.7 years) with lumbar osteopenia (T-score <−1.5) were recruited to examine the relationships between spine BMD and hip BMD and the associations of BMD with vertebral fractures. Lumbar BMD was assessed from L2 to L4, in the anteroposterior view, using dual-energy X-ray densitometry. At the upper left femur, hip BMD was measured at five regions of interest: femoral neck, trochanter, intertrochanter, Ward’s triangle and total hip. Spinal radiographs were analyzed independently by two trained investigators and vertebral fracture was defined as a reduction of at least 20% in the anterior, middle or posterior vertebral height. Spinal radiographs evidenced at least one vertebral crush fracture in 119 patients (59.5%). The results of logistic regression showed that age, femoral and spine BMDs were significant predictors of the presence of a vertebral fracture. Odds ratios for a decrease of 1 standard deviation ranged from 1.8 (1.3–2.8) for spine BMD to 2.3 (1.5–3.6) for total hip BMD. For multiple fractures odds ratios ranged from 1.7 (1.1–2.5) for spine BMD to 2.6 (1.7–4.3) for total hip BMD. In all models, odds ratios were higher for hip BMD than for spine BMD, particularly in younger men, under 50 years. A T-score <−2.5 in the femur (total femoral site) was associated with a 2.7-fold increase in the risk of vertebral fracture while a T-score <−2.5 in the spine was associated with only a 2-fold increase in risk. This study confirms the strong association of age and BMD with vertebral fractures in middle-aged men, shows that the femoral area is the best site of BMD measurement and suggests that a low femoral BMD could be considered as an index of severity in young men with lumbar osteopenia. Received: 27 October 1998 / Accepted: 22 February 1999     

Risk Factors for Perimenopausal Fractures: A Prospective Study

This prospective study was aimed at determining the risk factors for the development of fractures in perimenopausal women. The study group (n= 3068) was comprised of a stratified population sample of women aged between 47 and 56 years. During the follow-up period of 3.6 years, 257 (8.4%) of the women sustained a total of 295 fractures. After adjustment for covariates, the relative risk (RR) of sustaining a fracture was found to be 1.4 [95% confidence interval (CI) 1.2–1.6] for a 1 standard deviation (SD) decrease in the spinal and femoral neck bone mineral density (BMD). Women with a previous fracture history were found to have an increased risk of fracture [RR 1.7 (95% CI 1.3–2.2)] and those reporting three or more chronic illnesses exhibited a RR of 1.4 (95% CI 1.0–1.9). Women not using hormone replacement therapy (HRT) had a RR of 1.5 (95% CI 1.1–2.2) for all fracture types. When osteoporotic fractures (vertebral, hip, proximal humerus and wrist fractures; n= 98) were used as an endpoint, the independent risk factors were found to be a low BMD (RR for a 1 SD decrease in both spinal and femoral neck BMD was 1.6, 95% CI 1.3–2.0), a previous fracture history (RR 1.9, 95% CI 1.3–2.9) and nonuse of HRT (RR 2.2, 95% CI 1.3–4.0). The independent risk factors for all other fractures (n = 158) were a low BMD (RR for a 1 SD decrease in the spinal BMD was 1.4, 95% CI 1.2–1.6 and in the femoral neck BMD was 1.3, 95% CI 1.1–1.5), a previous fracture history (RR 1.6, 95% CI 1.1–2.2), smoking (RR 1.8, 95% CI 1.1–2.7) and having had three or more chronic illnesses (RR 1.6, 95% CI 1.1–2.2). Weight, height, age, menopausal status, maternal hip fracture, use of alcohol, coffee consumption or dietary calcium intake were not independently associated with the development of any particular type of fracture. We conclude that the independent risk factors for perimenopausal fractures are a low bone density, previous fracture history, nonuse of HRT, having had three or more chronic illnesses and smoking, the gradient of risk being similar for spinal and femoral neck BMD measurements in the perimenopausal population. The risk factors are slightly different for perimenopausal osteoporotic than for other types of fractures. Received: 6 April 1999 / Accepted: 18 August 1999     

Family History of Appendicular Fracture and Risk of Osteoporosis: A Population-Based Study

Family and twin studies demonstrate a strong genetic component to osteoporosis, suggesting that a positive family history for this disease may be an important clinical risk factor. We have therefore explored the extent to which a history of wrist fracture in a female first-degree relative was associated with an increased risk of prevalent fracture at both appendicular and vertebral sites in a cross-sectional study design. One thousand and three Caucasian women (age range 45–64 years) were studied from a UK population cohort. Bone mineral density (BMD) was measured at the lumbar spine and femoral neck using dual-energy X-ray absorptiometry. Appendicular fractures (wrist and hip) were recorded by questionnaire and validated from radiographs and hospital records. Vertebral fractures were assessed using radiologic survey of the thoracolumbar spine and semi-automated morphometric analysis. A positive family history of osteoporotic fracture (hip and/or wrist) in either a mother and/or sister was reported in 138 of the 1003 women. When compared with those with a negative family history of fracture, BMD was significantly reduced in those with a positive history at both the spine (p = 0.02) and the hip (p = 0.02). In total, there were 63 validated fragility fractures found in the 1003 women (16 wrist, 6 hip and 41 vertebral). Family history of osteoporotic fracture was associated with an increased total risk for osteoporotic fracture, with an odds ratio (95% confidence interval) of 2.02 (1.02, 3.78). Site-specific analysis showed that a positive family history of wrist fracture was associated with a considerably elevated risk of wrist fracture, with an odds ratio of 4.24 (1.44, 12.67). These increases in risk remained after adjustment for BMD, suggesting that other genetic factors account for the familial risk of osteoporosis and fracture. Received: 20 August 1998 / Accepted: 25 January 1999     

Effects of Gender and Age on the Association of Apolipoprotein E ε4 with Bone Mineral Density,Bone Turnover and the Risk of Fractures in Older People*

The aim of this study was to examine whether the presence of apolipoprotein E ε4 (ApoE ε4) is associated with a lower bone mineral density (BMD), lower quantitative ultrasound (QUS) measurements, higher bone turnover and fracture risk, and whether these relations are modified by gender and age. A total of 1406 elderly men and women (≥65 years) of the Longitudinal Aging Study Amsterdam (LASA) participated in this study. In all participants, QUS measurements were assessed, as well as serum osteocalcin (OC) and urine deoxypyridinolin (DPD/Cr urine). Follow-up of fractures was done each three months. In a subsample (n = 604), total body bone mineral content (BMC) and BMD of the hip and lumbar spine were measured. In addition, prevalent vertebral deformities were identified on radiographs. In women, the presence of ApoE ε4 was associated with significantly lower femoral neck BMD (g/cm²; mean ± SEM; ε4+, 0.64 ± 0.01 vs. ε4−, 0.67 ± 0.01; p= 0.04), lower trochanter BMD (g/cm²; mean ± SEM; ε4+, 0.58 ± 0.01 vs. ε4–, 0.61 ± 0.01; p= 0.01) and lower total body BMC (g; mean ± SEM; ε4+, 1787 ± 40.0 vs. ε4–, 1863 ± 23.8; p= 0.04). Women with ApoE ε4 also had a higher risk of severe vertebral deformities (OR=2.78; 95%CI: 1.21–6.34). In men, the associations between ApoE status and both hip BMD and QUS depended on age. Only among the younger men (65–69 years) was the presence of ApoE ε4 associated with lower BMD values. Bone markers and fractures were not associated with ApoE ε4 in either women, or men. In conclusion, this large community-based study confirms the importance of ApoE ε4 as a possible genetic risk factor related to BMD and vertebral deformities and demonstrates that its effect is gender related, and depends on age in men only. Received: 6 July 2001 / Accepted: 2 April 2002     

Sex Difference in the Validity of Vertebral Deformities as an Index of Prevalent Vertebral Osteoporotic Fractures: A Population Survey of Older Men and Women

Morphometric methods have been developed for standardized assessment of vertebral deformities in clinical and epidemiologic studies of spinal osteoporosis. However, vertebral deformity may be caused by a variety of other conditions. To examine the validity of morphometrically assessed vertebral deformities as an index of osteoporotic vertebral fractures, we developed an algorithm for radiological differential classification (RDC) based on a combination of quantitative and qualitative assessment of lateral spinal radiographs. Radiographs were obtained in a population of 50- to 80-year-old German women (n= 283) and men (n = 297) surveyed in the context of the European Vertebral Osteoporosis Study (EVOS). Morphometric methods (Eastell 3 SD and 4 SD criteria, McCloskey) were validated against RDC and against bone mineral density (BMD) at the femur and the lumbar spine. According to RDC 36 persons (6.2%) had at least one osteoporotic vertebral fracture; among 516 (88.9%) nonosteoporotics 154 had severe spondylosis, 132 had other spinal disease and 219 had normal findings; 14 persons (2.4%) could not be unequivocally classified. The prevalence of morphometrically assessed vertebral deformities ranged from 7.3% to 19.2% in women and from 3.5% to 16.6% in men, depending on the stringency of the morphometric criteria. The agreement between RDC and morphometric methods was poor. In men, 62–86% of cases with vertebral deformities were classified as nonosteoporotic (severe spondylosis or other spinal disease) by RDC, compared with 31–68% in women. Among these, most had wedge deformities of the thoracic spine. On the other hand, up to 80% of osteoporotic vertebral fractures in men and up to 48% in women were missed by morphometry, in particular endplate fractures at the lumbar spine. In the group with osteoporotic vertebral fractures by RDC the proportion of persons with osteoporosis according to the WHO criteria (T-score <−2.5 SD) was 90.0% in women and 86.6% in men, compared with 67.9–85.0% in women and 20.8–50.0% in men with vertebral deformities by various methods. Although vertebral deformities by most definitions were significantly and inversely related to BMD as a continuous variable in both sexes [OR; 95% CI ranged between (1.70; 1.07–2.70) and (3.69; 1.33–10.25)], a much stronger association existed between BMD and osteoporotic fractures defined by RDC [OR; 95% CI between (4.85; 2.30–10.24) and (15.40; 4.65–51.02)]. In the nonosteoporotic group individuals with severe spondylosis had significantly higher BMD values at the femoral neck (p <0.01) and lumbar spine (p <0.0004) compared with the normal group. On the basis of internal (RDC) and external (BMD) validation, we conclude that assessment of vertebral osteoporotic fracture by quantitative methods alone will result in considerable misclassification, especially in men. Criteria for differential diagnosis as used within RDC can be helpful for a standardized subclassification of vertebral deformities in studies of spinal osteoporosis. Received: 5 February 1999 / Accepted: 24 June 1999     

Prevalent Vertebral Deformity Predicts Incident Hip though not distal Forearm Fracture: Results from the European Prospective Osteoporosis Study

The presence of a vertebral deformity increases the risk of subsequent spinal deformities. The aim of this analysis was to determine whether the presence of vertebral deformity predicts incident hip and other limb fractures. Six thousand three hundred and forty-four men and 6788 women aged 50 years and over were recruited from population registers in 31 European centers and followed prospectively for a median of 3 years. All subjects had radiographs performed at baseline and the presence of vertebral deformity was assessed using established morphometric methods. Incident limb fractures which occurred during the follow- up period were ascertained by annual postal questionnaire and confirmed by radiographs, review of medical records and personal interview. During a total of 40 348 person-years of follow-up, 138 men and 391 women sustained a limb fracture. Amongst the women, after adjustment for age, prevalent vertebral deformity was a strong predictor of incident hip fracture, (rate ratio (RR) = 4.5; 95% CI 2.1–9.4) and a weak predictor of ‘other’ limb fractures (RR = 1.6; 95% CI 1.1–2.4), though not distal forearm fracture (RR = 1.0; 95% CI 0.6–1.6). The predictive risk increased with increasing number of prevalent deformities, particularly for subsequent hip fracture: for two or more deformities, RR = 7.2 (95% CI 3.0–17.3). Amongst men, vertebral deformity was not associated with an increased risk of incident limb fracture though there was a nonsignificant trend toward an increased risk of hip fracture with increasing number of deformities. In summary, prevalent radiographic vertebral deformities in women are a strong predictor of hip fracture, and to a lesser extent humerus and ‘other’ limb fractures; however, they do not predict distal forearm fractures. Received: 23 February 2000 / Accepted: 11 August 2000     

Proximal Femur Geometry To Detect and Distinguish Femoral Neck Fractures from Trochanteric Fractures in Postmenopausal Women

Some proximal femur geometry (PFG) parameters, measured by dual-energy X-ray absorptiometry (DXA), have been reported to discriminate subjects with hip fracture. Relatively few studies have tested their ability to discriminate femoral neck fractures from those of the trochanter. To this end we performed a cross-sectional study in a population of 547 menopausal women over 69 years of age with femoral neck fractures (n= 88), trochanteric fractures (n= 93) or controls (n= 366). Hip axis length (HAL), neck–shaft angle (NSA), femoral neck diameter (FND) and femoral shaft diameter (FSD) were measured by DXA, as well as the bone mineral density (BMD) of the nonfractured hip at the femoral neck, trochanter and Ward’s triangle. In fractured subjects, BMD was lower at each measurement site. HAL was longer and NSA wider in those with femoral neck fractures. With logistic regression the age-adjusted odds ratio (OR) for a 1 standard deviation (SD) decrease in BMD was significantly associated at each measurement site with femoral neck fracture (femoral neck BMD: OR 1.9, 95% confidence interval (95% CI): 1.4–2.5; trochanter BMD: OR 1.6, 95% CI 1.2–2.0; Ward’s triangle BMD: OR 1.7, 95% CI 1.3–2.2) and trochanteric fracture (femoral neck BMD: OR 2.6, 95% CI 1.9–3.6; trochanter BMD: OR 3.0, 95% CI 2.2–4.1; Ward’s triangle BMD: OR 1.8, 95% CI 1.4–2.3). Age-adjusted OR for 1 SD increases in NSA (OR 2.2, 95% CI 1.7–2.8) and HAL (OR 1.3, 95% CI 1.1–1.6) was significantly associated with the fracture risk only for femoral neck fracture. In the best predictive model the strongest predictors were site-matched BMD for both fracture types and NSA for neck fracture. Trochanteric BMD had the greatest area (0.78, standard error (SE) 0.02) under the receiver operating characteristic curve in trochanteric fractures, whereas for NSA (0.72, SE 0.03) this area was greatest in femoral neck fractures. These results confirm the association of BMD with proximal femur fracture and support the evidence that PFG plays a significant role only in neck fracture prediction, since NSA is the best predictive parameter among those tested. Received: 24 April 2001 / Accepted: 1 August 2001     

A Randomized Trial of Sodium Fluoride (60 mg) ± Estrogen in Postmenopausal Osteoporotic Vertebral Fractures: Increased Vertebral Fractures and Peripheral Bone Loss with Sodium Fluoride; Concurrent Estrogen Prevents Peripheral Loss, But Not Vertebral Fractures

Postmenopausal Caucasian women aged less than 80 years (n= 99) with one or more atraumatic vertebral fracture and no hip fractures, were treated by cyclical administration of enteric coated sodium fluoride (NaF) or no NaF for 27 months, with precautions to prevent excessive stimulation of bone turnover. In the first study 65 women, unexposed to estrogen (–E study), age 70.8 ± 0.8 years (mean ± SEM) were all treated with calcium (Ca) 1.0–1.2 g daily and ergocalciferol (D) 0.25 mg per 25 kg once weekly and were randomly assigned to cyclical NaF (6 months on, 3 months off, initial dose 60 mg/day; group F CaD, n= 34) or no NaF (group CaD, n= 31). In the second study 34 patients, age 65.5 ± 1.2 years, on hormone replacement therapy (E) at baseline, had this standardized, and were all treated with Ca and D and similarly randomized (FE CaD, n= 17; E CaD, n= 17) (+E study). The patients were stratified according to E status and subsequently assigned randomly to ± NaF. Seventy-five patients completed the trial. Both groups treated with NaF showed an increase in lumbar spinal density (by DXA) above baseline by 27 months: FE CaD + 16.2% and F CaD +9.3% (both p= 0.0001). In neither group CaD nor E CaD did lumbar spinal density increase. Peripheral bone loss occurred at most sites in the F CaD group at 27 months: tibia/fibula shaft –7.3% (p= 0.005); femoral shaft –7.1% (p= 0.004); distal forearm –4.0% (p = 0.004); total hip –4.1% (p = 0.003); and femoral neck –3.5% (p= 0.006). No significant loss occurred in group FE CaD. Differences between the two NaF groups were greatest at the total hip at 27 months but were not significant [p<0.05; in view of the multiple bone mineral density (BMD) sites, an alpha of 0.01 was employed to denote significance in BMD changes throughout this paper]. Using Cox’s proportional hazards model, in the –E study there were significantly more patients with first fresh vertebral fractures in those treated with NaF than in those not so treated (RR = 24.2, p= 0.008, 95% CI 2.3–255). Patients developing first fresh fractures in the first 9 months were markedly different between groups: –23% of F CaD, 0 of CaD, 29% of FE CaD and 0 of E CaD. The incidence of incomplete (stress) fractures was similar in the two NaF-treated groups. Complete nonvertebral fractures did not occur in the two +E groups; there were no differences between groups F CaD and CaD. Baseline BMD (spine and femoral neck) was related to incident vertebral fractures in the control groups (no NaF), but not in the two NaF groups. Our results and a literature review indicate that fluoride salts, if used, should be at low dosage, with pretreatment and co-treatment with a bone resorption inhibitor. Received: 22 August 2000 / Accepted: 23 July 2001     

Digital X-Ray Radiogrammetry Identifies Women at Risk of Osteoporotic Fracture: Results from a Prospective Study

Using digital X-ray radiogrammetry (DXR) on hand radiographs from a large population-based study, 1,370 postmenopausal women were evaluated in a prospective fashion; fracture occurrence was compared with DXR measurements of historic radiographs. Further, the aim of the study was to evaluate factors affecting DXR bone mineral density (BMD) in this cohort. The study is based on data from a subgroup of women participating in the third Copenhagen City Heart Study and additional data from a questionnaire obtained in 1999. The mean follow-up time was 6.1 years. During the observation period, 245 women suffered a fracture. Odds ratios (ORs) per 1 standard deviation decline in DXR-BMD were statistically significant for fracture in the groups of wrist fractures, proximal humerus fractures, vertebral fractures, and other fractures as well as in the total fracture group. In the hip fracture group, the P value almost reached significance (0.052). The highest ORs (2.4) were found in the group with proximal humerus fractures and in the vertebral fracture group (2.0). In the wrist fracture and hip fracture groups, ORs were 1.7 and 1.4, respectively. The group with other fractures had an OR of 1.7, and the OR in the entire fracture group was 1.6. Age, fracture, and smoking were negatively correlated with DXR-BMD, whereas BMI, age at menopause, hormone replacement therapy, and physical fitness and muscle strength were positively correlated with DXR-BMD. In conclusion, BMD estimated by DXR of the metacarpals predicts later osteoporotic fracture and seems to provide meaningful information on bone mass in epidemiological studies, where DXA measurements are not available.     

Quantitative Ultrasound and Bone Densitometry to Evaluate the Risk of Nonspine Fractures: A Prospective Study

The ability of quantitative ultrasound (QUS) to estimate the risk of osteoporotic fractures was evaluated in a prospective study over a mean time of 5.47 years in 254 postmenopausal women (mean age 58.06 ± 7.67 years). Baseline measurements of ultrasound transmission velocity (UTV) and bone mineral density (BMD) were taken at the distal radius (DR). UTV was also measured at the patella (P). Fifty nonspine fractures due to minor trauma were detected during annual check-ups with an incidence of 3.59/year. Fractures occurred in older women with a lower BMD and QUS. Using Cox regression analysis the relative risk (RR) per 1 standard deviation (SD) decrease in the unadjusted QUS and BMD measurements was: BMD-DR = 3.56, 95% confidence interval (CI) 1.57–8.09; UTV-DR = 5.35, 95% CI 2.07–13.83; UTV-P = 4.49, 95% CI 2.08–9.68. The relationship between BMD and QUS variables and fracture risk persisted after adjusting for potential confounders apart from previous fractures, giving the following RR: BMD-DR = 2.99, 95% CI 1.06–8.41; UTV-DR = 3.69, 95% CI 1.18–11.49; UTV-P = 3.89, 95% CI 1.53–9.90. Correcting also for previous fractures, only UTV-P remained an effective predictor of fracture risk even after QUS measurement correction for BMD. Wrist fractures were best related to BMD-DR (RR 7.33, 95% CI 1.43–37.50) and UTV-DR (RR 10.94, 95% CI 1.10–108.45), while hip and ankle fractures were significantly associated only with UTV-P (hip: RR 32.14, 95% CI 1.83–562.80; ankle: RR 17.60, 95% CI 1.78–173.79). The combined use of BMD and QUS is a better predictor of fracture risk than either technique used separately. Comparison of the areas under the receiver operating characteristic (ROC) curves did not show differences in the ability of BMD and QUS to correctly distinguish fractures. In conclusion, QUS predicts fracture risk in osteoporotic women at least as well as BMD. UTV-DR and BMD-DR are good predictors of wrist fractures, while UTV-P is strongly related to hip and ankle fractures. QUS and BMD combined improve the diagnostic ability of each technique individually. Received: 27 April 1999 / Accepted: 3 December 1999     

Vitamin D Receptor Gene Polymorphisms, Bone Mass, Bone Loss and Prevalence of Vertebral Fracture: Differences in Postmenopausal Women and Men

Bone mineral density (BMD), the major determinant of fracture risk, is under strong genetic control. Although polymorphisms of the vitamin D receptor (VDR) gene have been suggested to account for some of the genetic variation in bone mass, the influence of VDR genotypes on osteoporosis remains controversial. Previous published studies have focused mainly on women, but the pattern of response in men has not been determined. Using the BsmI restriction enzyme, we studied the influence of the different VDR genotypes on bone mass, bone loss and the prevalence of vertebral fractures in a population-based sample of both sexes (n = 326). BMD was measured at the lumbar spine and femoral neck, with a 4-year interval, using dual-energy X-ray absorptiometry. Vertebral fractures were assessed by two lateral radiographs at the beginning and end of the study. The prevalence of the three possible VDR genotypes was similar to those in other Caucasian populations and no differences were found between men and women. Women with the favorable bb genotype showed significantly higher BMD values at the lumbar spine and femoral neck, and a positive rate of BMD change at the femoral neck compared with women with the BB and Bb genotypes. Moreover, women with the bb genotype showed a trend toward a lower prevalence and incidence of vertebral fractures (p= 0.07). We have not found any differences between VDR genotypes in men. In conclusion, VDR gene polymorphisms are related to bone mass and bone loss in women; also a trend in the prevalence of vertebral fractures was observed in postmenopausal women but not in men. Received: 8 June 1998 / Accepted: 7 December 1998     

Serum Bone Alkaline Phosphatase and Calcaneus Bone Density Predict Fractures: A Prospective Study

The aim of this study was to assess the ability of serum bone-specific alkaline phosphatase (bone ALP), creatinine-corrected urinary collagen crosslinks (CTx) and calcaneus bone mineral density (BMD) to identify postmenopausal women who have an increased risk of osteoporotic fractures. Calcaneus BMD and biochemical markers of bone turnover (serum bone ALP and urinary CTx) were measured in 512 community-dwelling postmenopausal women (mean age at baseline 69 years) participating in the Hawaii Osteoporosis Study. New spine and nonspine fractures subsequent to the BMD and biochemical bone markers measurements were recorded over an average of 2.7 years. Lateral spinal radiographs were used to identify spine fractures. Nonspine fractures were identified by self-report at the time of each examination. During the 2.7-year follow-up, at least one osteoporotic fracture occurred in 55 (10.7%) of the 512 women. Mean baseline serum bone ALP and urinary CTx were significantly higher among women who experienced an osteoporotic fracture compared with those women who did not fracture. In separate age-adjusted logistic regression models, serum bone ALP, urinary CTx and calcaneus BMD were each significantly associated with new fractures (odds ratios of 1.53, 1.54 and 1.61 per SD, respectively). Multiple variable logistic regression analysis identified BMD and serum bone ALP as significant predictors of fracture (p = 0.002 and 0.017, respectively). The results from this investigation indicate that increased bone turnover is significantly associated with an increased risk of osteoporotic fracture in postmenopausal women. This association is similar in magnitude and independent of that observed for BMD. Received: 18 June 1999 / Accepted: 21 June 1999     

Does a Fracture at One Site Predict Later Fractures at Other Sites? A British Cohort Study

The extent to which a fracture at one skeletal site predicts further fractures at other sites remains uncertain. We addressed this issue using information from the UK General Practice Research Database, which contains the medical records of general practitioners; our study population consisted of all patients aged 20 years or older with an incident fracture during 1988 to 1998. We identified 222 369 subjects (119 317 women, 103 052 men) who had sustained at least one fracture during follow-up. There was a 2- to 3-fold increase in the risk of subsequent fractures at different skeletal sites. A patient with a radius/ulna fracture had a standardized incidence ratio (SIR) of 3.0 (95% confidence interval 2.9–3.1) for fractures at a different skeletal site; for initial vertebral fracture, this ratio was 2.9 (2.8–3.1) and for initial femur/hip fracture it was 2.6 (2.5–2.7). The SIRs were generally higher among men than women. Men aged 65–74 years with a radius/ulna fracture or vertebral fracture had substantially higher rates of subsequent femur/hip fractures than expected; SIRs were 6.0 (3.4–9.9) and 13.4 (7.3–22.5). Corresponding SIRs among women of similar age were 3.3 (2.8–3.9) and 5.8 (4.1–8.1), respectively. Men and women aged 65 years or older with a vertebral fracture had a 5-year risk of femur/hip fracture of 6.7% and 13.3%, respectively. Our results indicate that fractures at any site are strong risk factors for subsequent fractures, among both elderly men and women. Received: 19 November 2001 / Accepted: 13 February 2002     

Fractal Analysis of Trabecular Bone Texture on Calcaneus Radiographs: Effects of Age, Time Since Menopause and Hormone Replacement Therapy

An analysis of trabecular bone texture based on fractal mathematics, when applied to trabecular bone images on plain radiographs, can be considered as a reflection of trabecular bone microarchitecture. It has been shown to be able to distinguish postmenopausal osteoporosis cases from controls. This cross-sectional study was carried out to investigate the influence of age, time since menopause and hormone replacement therapy (HRT) on the fractal dimension of trabecular bone texture at the calcaneus in a sample of 537 healthy women. Fractal analysis of texture was performed on calcaneus radiographs and the result expressed as the Hmean parameter (H = 2–fractal dimension). Total hip, femoral neck and lumbar spine bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. There was a statistically significant Hmean parameter decrease with age (p<0.0001) but the degree of correlation was low (r=–0.2) compared with the correlation between age and BMD (r=–0.36 to –0.61 according to the BMD site). We found a weak but statistically significant correlation between time since menopause and Hmean (r=–0.14, p= 0.03) in the 241 postmenopausal women included in the study. Hmean was significantly lower in a group of postmenopausal women without HRT (n= 110) compared with a group of age-matched postmenopausal women with HRT (n = 110): respectively 0.683 ± 0.043 and 0.695 ± 0.038 (p= 0.03). In conclusion, this study suggests that there is a menopause- and age-related decrease in the Hmean parameter and that HRT interferes with the results of the fractal analysis of trabecular bone texture on calcaneus radiographs. Received: 2 March 2001 / Accepted: 2 October 2001     

Metacarpal Morphometry Using a Semi-automated Technique in the Assessment of Osteoporosis and Vertebral Fracture Risk

Metacarpal morphometry represents a potentially cheap and widely available non-invasive assessment of skeletal status. In two cross-sectional studies, we compared the performance characteristics of a semi-automated technique (the Teijin Bonalyzer) with an in-house manual measurement, and with measures of skeletal strength at other sites. The metacarpal cortical index (mCI) was measured on hand radiographs of 178 osteoporotic women using both the Teijin Bonalyzer and a digitizing tablet. Measurements on the latter were consistently lower than with the Bonalyzer except for mCI (0.443 ± 0.080 vs 0.364 ± 0.060, p<0.001), although correlation coefficients between these two methods were highly significant (r= 0.62–0.83, p<0.001). The reproducibility errors of metacarpal bone mineral density (mBMD) were constant (1.1–1.2%) whilst those for mCI showed a marked operator-dependency (2.0–7.9%). In 379 elderly community-dwelling women, Bonalyzer mCI and mBMD showed a significant decline with age (r=−0.30 and −0.27 respectively, p<0.05). Both mCI and mBMD correlated significantly with forearm BMD (r= 0.50 and 0.57 respectively, p<0.001) and hip BMD (r= 0.48 and 0.53 respectively, p<0.001). After adjustment for age and weight, hip BMD demonstrated the best discrimination for prevalent vertebral fractures as judged by the gradient of risk for a 1 SD decrease in measurement (odds ratio (OR) 2.17, 95% CI 1.56–3.01). Similar but smaller gradients of risk were shown by Bonalyzer mCI (OR 1.32, 95% CI 1.00–1.75), mBMD (OR 1.35, 95% CI 1.02–1.78) and forearm BMD (OR 1.39, 95% CI 1.08–1.80). MCI, and in particular mBMD, may be useful assessments of bone mass and fracture risk. In our study, it is comparable to peripheral assessment of skeletal status by forearm densitometry. Received: 22 February 2000 / Accepted: 6 June 2000     

Vertebral Fractures Predict Subsequent Fractures

This population-based study documents an increase in most types of fractures following the occurrence of a clinically recognized vertebral fracture among 820 Rochester, Minnesota, residents. During 4349 person-years of follow-up, 896 new fractures were observed. Relative to incidence rates in the community, there was a 2.8-fold increase in the risk of any fracture, which was greater in men (standardized incidence ratio (SIR), 4.2; 95% CI, 3.2–5.3) than women (SIR, 2.7; 95% CI, 2.4–3.0). The estimated cumulative incidence of any fracture after 10 years was 70%. The greatest increase in risk was for subsequent fractures of the axial skeleton, in particular a 12.6-fold increase (95% CI, 11–14) in additional vertebral fractures. There was a lesser increase in most limb fractures, including a 2.3-fold increase (95% CI, 1.8–2.9) in hip fractures and a 1.6-fold increase (95% CI, 1.01–2.4) in distal forearm fractures. There was a slightly greater association with distal forearm fractures among those whose first vertebral fracture occurred before age 70 years but a similar relationship with hip fractures, including cervical and intertrochanteric hip fractures separately, regardless of age at the initial vertebral fracture. There was also an equivalent increase in subsequent fracture risk whether the initial vertebral fracture was attributed to severe or moderate trauma. These data show that vertebral fractures represent an important risk factor for fractures in general, not just those of the spine and hip. Received: 2 September 1998 / Accepted: 9 February 1999     

Impact of Hip and Vertebral Fractures on Quality-Adjusted Life Years

The objective of the study was to estimate the impact of hip and vertebral fractures on quality of life in postmenopausal women using a preference-based health measure that is appropriate for economic evaluations and to investigate correlates of health outcome. Interviews to assess health-related quality of life, which also documented other health conditions and characteristics, were undertaken in women age 50 years and older without osteoporotic fractures compared with women with hip and/or vertebral fracture(s). Health status was characterized by self-reported physical limitations and the mental and physical component summary scores of the SF-36. Quality-adjusted life years (QALYs), which reflect each individual’s assessment of her overall health utility, were estimated with time tradeoff values. Regression methods were used to examine QALY correlates (e.g. time since fracture) for each fracture group and to estimate differences in QALYs between fracture and non-fracture subjects after accounting for other patient characteristics. Among 382 women ages 50–96 years, fracture subjects were significantly older, less likely to use hormone replacement therapy and more likely to report physical limitations than non-fracture subjects. On the QALY scale, where 1 represents perfect health and 0 represents death, mean QALY values were 0.82 (95% CI: 0.76, 0.87) among 114 women with one or more vertebral fractures and 0.63 (95% CI: 0.52, 0.74) among 67 with hip fracture compared with 0.91 (95% CI: 0.88, 0.94) among 201 women without fracture. No significant correlates of QALYs were identified among women with vertebral fracture alone. Among hip fracture subjects, time since hip fracture and presence of a vertebral fracture were significant correlates of QALYs. In multiple regression analyses, estimated QALY differences (fracture minus non-fracture subjects) ranged from –0.05 to –0.55 and were equivalent to losses of 20–58 days, 23–65 days and 115–202 days per year for vertebral fracture (p= 0.001), hip fracture (p= 0.009) and hip plus vertebral fracture (p<0.001) subjects, respectively, depending on age. Thus to adequately assess the cost-effectiveness of osteoporosis treatment, the negative impact of vertebral fractures on QALYs, even among women who have survived a hip fracture, must be considered. Received: 2 February 2001 / Accepted: 23 July 2001     

Effects of Alendronate on Bone Density in Men with Primary and Secondary Osteoporosis

Alendronate has been reported to increase bone mineral density (BMD) and reduce fracture risk in women with osteoporosis. As there are no proven safe and effective treatments available for men with osteoporosis, we compared the effects of alendronate (10 mg/day) on BMD, measured using dual-energy X-ray absorptiometry, in a 12-month prospective, controlled, open label study involving (i) men with primary (n= 23) or secondary osteoporosis (n= 18), (ii) postmenopausal women with primary (n= 18) or secondary (n= 21) osteoporosis, and (iii) 29 male and 14 female untreated controls matched by age, height and weight. The patients had one or more vertebral fractures and ranged in age from 34.6 to 85.1 years. BMD was detectably increased relative to baseline by 6 months, and increased by comparable amounts in males and females with primary or secondary osteoporosis. At 12 months, lumbar spine BMD was 5.4%± 1.1% to 7.0%± 2.2% higher in the treated groups compared with baseline and controls (p<0.05 to 0.0001). Trochanteric BMD increased by 2.6%± 1.5% and 3.7%± 1.7% in treated men with primary and secondary osteoporosis, respectively (p = 0.06 to 0.08), and by 3.9%± 1.3% in treated women with primary osteoporosis (p<0.01) after 12 months. No significant changes were detected at the femoral neck or Ward’s triangle. BMD remained unchanged in controls. We infer that alendronate has comparable incremental effects on BMD in men and women with primary and secondary osteoporosis within 12 months of treatment. The changes are in the order of 0.5 SD – effects associated with a clinically worthwhile reduction in fracture risk. The data provide room for optimism regarding the role of alendronate in the treatment of osteoporosis in men. Randomized, double-masked and placebo-controlled trials are needed to confirm these preliminary findings and demonstrate antifracture efficacy using vertebral and nonvertebral fracture rates as the primary endpoint. Received: 23 February 1999 / Accepted: 2 June 1999     

The Tromsø Study: Registration of Fractures, How Good are Self-reports, a Computerized Radiographic Register and a Discharge Register?

In order to compare different methods of fracture registration, we sought all nonvertebral fractures suffered during 8 years (1988–95) among 21 441 persons invited to a survey in 1979/80. We registered a total of 54 hip fracture cases through three separate sources (self-report, computer linkage to the local radiographic archives, discharge register), whereas forearm fractures (a total of 291 cases) were registered through two separate sources (self-report, computer linkage to the radiographic archives). The registration of fractures at other sites (a total of 1321 cases) were from one source (computer linkage to the local radiographic archives), and we have compared three ways of obtaining data from this single source (no ascertainment, ascertainment of records coded as fracture, ascertainment of all records). Ninety-three percent of all hip fractures and 97% of all wrist fractures in the entire study population were found by computer linkage to the radiographic archives, whereas the discharge register detected 87% of all the hip fractures. Computer linkage with ascertainment gave no overreporting of fractures. Among the 11 626 persons who answered a follow-up questionnaire in 1994/95, 97% (CI 84–100%) of all hip fractures and 72% (CI 66–78%) of all wrist fractures were self-reported. We conclude that a computerized search of radiographic archives is a viable method of fracture registration. Received: 8 February 1999 / Accepted: 11 June 2001