A patient-level key performance indicator set to measure the effectiveness of fracture liaison services and guide quality improvement: a position paper of the IOF Capture the Fracture Working Group, National Osteoporosis Foundation and Fragility Fracture Network

The International Osteoporosis Foundation (IOF) Capture the Fracture® Campaign with the Fragility Fracture Network (FFN) and National Osteoporosis Foundation (NOF) has developed eleven patient-level key performance indicators (KPIs) for fracture liaison services (FLSs) to guide quality improvement.

INTRODUCTION

Fracture Liaison Services (FLSs) are recommended worldwide to reduce fracture risk after a sentinel fracture. Given not every FLS is automatically effective, the IOF Capture the Fracture working group has developed and implemented the Best Practice Framework to assess the organisational components of an FLS. We have now developed a complimentary KPI set that extends this assessment of performance to the patient level.

METHODS

The Capture the Fracture working group in collaboration with the Fragility Fracture Network Secondary Fragility Fracture Special Interest Group and National Osteoporosis Foundation adapted existing metrics from the UK-based Fracture Liaison Service Database Audit to develop a patient-level KPI set for FLSs.

RESULTS

Eleven KPIs were selected. The proportion of patients: with non-spinal fractures; with spine fractures (detected clinically and radiologically); assessed for fracture risk within 12 weeks of sentinel fracture; having DXA assessment within 12 weeks of sentinel fracture; having falls risk assessment; recommended anti-osteoporosis medication; commenced of strength and balance exercise intervention within 16 weeks of sentinel fracture; monitored within 16 weeks of sentinel fracture; started anti-osteoporosis medication within 16 weeks of sentinel fracture; prescribed anti-osteoporosis medication 52 weeks after sentinel fracture. The final KPI measures data completeness for each of the other KPIs. For these indicators, levels of achievement were set at the < 50%, 50-80% and > 80% levels except for treatment recommendation where a level of 50% was used.

CONCLUSION

This KPI set compliments the existing Best Practice Framework to support FLSs to examine their own performance using patient-level data. By using this KPI set for local quality improvement cycles, FLSs will be able to efficiently realise the full potential of secondary fracture prevention and improved clinical outcomes for their local populations.

Diagnosis and management of bone fragility in diabetes: an emerging challenge

Fragility fractures are increasingly recognized as a complication of both type 1 and type 2 diabetes, with fracture risk that increases with disease duration and poor glycemic control. Yet the identification and management of fracture risk in these patients remains challenging. This review explores the clinical characteristics of bone fragility in adults with diabetes and highlights recent studies that have evaluated bone mineral density (BMD), bone microstructure and material properties, biochemical markers, and fracture prediction algorithms (i.e., FRAX) in these patients. It further reviews the impact of diabetes drugs on bone as well as the efficacy of osteoporosis treatments in this population. We finally propose an algorithm for the identification and management of diabetic patients at increased fracture risk.

Hip fracture, mortality risk, and cause of death over two decades

Men and women with hip fracture have higher short-term mortality. This study investigated mortality risk over two decades post-fracture; excess mortality remained high in women up to 10 years and in men up to 20 years. Cardiovascular disease (CVD) and pneumonia were leading causes of death with a long-term doubling of risk.

INTRODUCTION

Hip fractures are associated with increased mortality, particularly short term. In this study with a two-decade follow-up, we examined mortality and cause of death compared to the background population.

METHODS

We followed 1013 hip fracture patients and 2026 matched community controls for 22 years. Mortality, excess mortality, and cause of death were analyzed and stratified for age and sex. Hazard ratio (HR) was estimated by Cox regression. A competing risk model was fitted to estimate HR for common causes of death (CVD, cancer, pneumonia) in the short and long term (>1 year).

RESULTS

For both sexes and at all ages, mortality was higher in hip fracture patients across the observation period with men losing most life years (p < 0.001). Mortality risk was higher for up to 15 years (women (risk ratio (RR) 1.9 [95 % confidence interval (CI) 1.7-2.1]); men (RR 2.8 [2.2-3.5])) and until end of follow-up ((RR 1.8 [1.6-2.0]); (RR 2.7 [2.1-3.3])). Excess mortality by time intervals, censored for the first year, was evident in women (<80 years, up to 10 years; >80 years, for 5 years) and in men <80 years throughout. CVD and pneumonia were predominant causes of death in men and women with an associated higher risk in all age groups. Pneumonia caused excess mortality in men over the entire observation period.

CONCLUSION

In a remaining lifetime perspective, all-cause and excess mortality after hip fracture was higher even over two decades of follow-up. CVD and pneumonia reduce life expectancy for the remaining lifetime and highlights the need to further improve post-fracture management.

Effective secondary fracture prevention: implementation of a global benchmarking of clinical quality using the IOF Capture the Fracture® Best Practice Framework tool

Fracture Liaison Services are the best model to prevent secondary fractures. The International Osteoporosis Foundation developed a Best Practice Framework to provide a quality benchmark. After a year of implementation, we confirmed that a single framework with set criteria is able to benchmark services across healthcare systems worldwide.

INTRODUCTION

Despite evidence for the clinical effectiveness of secondary fracture prevention, translation in the real-world setting remains disappointing. Where implemented, a wide variety of service models are used to deliver effective secondary fracture prevention. To support use of effective models of care across the globe, the International Osteoporosis Foundation's Capture the Fracture® programme developed a Best Practice Framework (BPF) tool of criteria and standards to provide a quality benchmark. We now report findings after the first 12 months of implementation.

METHODS

A questionnaire for the BPF was created and made available to institutions on the Capture the Fracture website. Responses from institutions were used to assign gold, silver, bronze or black (insufficient) level of achievements mapped across five domains. Through an interactive process with the institution, a final score was determined and published on the Capture the Fracture website Fracture Liaison Service (FLS) map.

RESULTS

Sixty hospitals across six continents submitted their questionnaires. The hospitals served populations from 20,000 to 15 million and were a mix of private and publicly funded. Each FLS managed 146 to 6200 fragility fracture patients per year with a total of 55,160 patients across all sites. Overall, 27 hospitals scored gold, 23 silver and 10 bronze. The pathway for the hip fracture patients had the highest proportion of gold grading while vertebral fracture the lowest.

CONCLUSION

In the first 12 months, we have successfully tested the BPF tool in a range of health settings across the globe. Initial findings confirm a significant heterogeneity in service provision and highlight the importance of a global approach to ensure high quality secondary fracture prevention services.

Vitamin D insufficiency over 5 years is associated with increased fracture risk-an observational cohort study of elderly women

This study of elderly Swedish women investigated the association between chronic vitamin D insufficiency and osteoporotic fractures occurring between ages 80-90. The incidence and risk of hip and major osteoporotic fractures was significantly higher in elderly women with low vitamin D levels maintained over 5 years.

INTRODUCTION

Vitamin D insufficiency among the elderly is common; however, relatively little is known about the effects of long-term hypovitaminosis D on fracture. We investigated sequential assessment of serum 25(OH)D at age 75 and 80 to determine if continuously low 25(OH)D levels are associated with increased 10-year fracture incidence.

METHODS

One thousand forty-four Swedish women from the population-based OPRA cohort, all 75 years old, attended at baseline (BL); 715 attended at 5 years. S-25(OH)D was available in 987 and 640, respectively and categorized as: <50 (Low), 50-75 (Intermediate), and >75 nmol/L (High). Incident fracture data was collected with maximum follow-up to 90 years of age.

RESULTS

Hip fracture incidence between age 80-85 was higher in women who had low 25(OH)D at both baseline and 5 years (22.2 % (Low) vs. 6.6 % (High); p = 0.003). Between age 80-90, hip fracture incidence was more than double that of women in the high category (27.9 vs. 12.3 %; p = 0.006). Within 5-years, 50 % of women in the continuously low group compared to 34 % in the continuously high 25(OH)D group had an osteoporotic fracture (p = 0.004) while 10-year incidence was higher compared to the intermediate (p = 0.020) but not the high category (p = 0.053). The 10-year relative risk of hip fracture was almost three times higher and osteoporotic fracture risk almost doubled for women in the lowest 25(OH)D category compared to the high category (HR 2.7 and 1.7; p = 0.003 and 0.023, respectively).

CONCLUSION

In these elderly women, 25(OH)D insufficiency over 5-years was associated with increased 10-year risk of hip and major osteoporotic fractures.

Self-reported recreational exercise combining regularity and impact is necessary to maximize bone mineral density in young adult women: a population-based study of 1,061 women 25 years of age

Recreational physical activity in 25-year-old women in Sweden increases bone mineral density (BMD) in the trochanter by 5.5% when combining regularity and impact. Jogging and spinning were especially beneficial for hip BMD (6.4-8.5%). Women who enjoyed physical education in school maintained their higher activity level at age 25.

INTRODUCTION

The aims of this study were to evaluate the effects of recreational exercise on BMD and describe how exercise patterns change with time in a normal population of young adult women.

METHODS

In a population-based study of 1,061 women, age 25 (±0.2), BMD was measured at total body (TB-BMD), femoral neck (FN-BMD), trochanter (TR-BMD), and spine (LS-BMD). Self-reported physical activity status was assessed by questionnaire. Regularity of exercise was expressed as recreational activity level (RAL) and impact load as peak strain score (PSS). A permutation (COMB-RP) was used to evaluate combined endurance and impacts on bone mass.

RESULTS

More than half of the women reported exercising on a regular basis and the most common activities were running, strength training, aerobics, and spinning. Seventy percent participated in at least one activity during the year. Women with high RAL or PSS had higher BMD in the hip (2.6-3.5%) and spine (1.5-2.1%), with the greatest differences resulting from PSS (p < 0.001-0.02). Combined regularity and impact (high-COMB-RP) conferred the greatest gains in BMD (FN 4.7%, TR 5.5%, LS 3.1%; p < 0.001) despite concomitant lower body weight. Jogging and spinning were particularly beneficial for hip BMD (+6.4-8.5%). Women with high-COMB-RP scores enjoyed physical education in school more and maintained higher activity levels throughout compared to those with low scores.

CONCLUSION

Self-reported recreational levels of physical activity positively influence BMD in young adult women but to maximize BMD gains, regular, high-impact exercise is required. Enjoyment of exercise contributes to regularity of exercising which has short- and long-term implications for bone health.

Balloon kyphoplasty and vertebroplasty in the management of vertebral compression fractures

Vertebral compression fractures (VCFs) are the most prevalent fractures in osteoporotic patients. The classical conservative management of these fractures is through rest, pain medication, bracing and muscle relaxants. The aim of this paper is to review prospective controlled studies comparing the efficacy and safety of minimally invasive techniques for vertebral augmentation, vertebroplasty (VP) and balloon kyphoplasty (BKP), versus non-surgical management (NSM). The Fracture Working Group of the International Osteoporosis Foundation conducted a literature search and developed a review paper on VP and BKP. The results presented for the direct management of osteoporotic VCFs focused on clinical outcomes of these three different procedures, including reduction in pain, improvement of function and mobility, vertebral height restoration and decrease in spinal curvature (kyphosis). Overall, VP and BKP are generally safe procedures that provide quicker pain relief, mobility recovery and in some cases vertebral height restoration than conventional conservative medical treatment, at least in the short term. However, the long-term benefits and safety in terms of risk of subsequent vertebral fractures have not been clearly demonstrated and further prospective randomized studies are needed with standards for reporting. Referral physicians should be aware of VP/BKP and their potential to reduce the health impairment of patients with VCFs. However, VP and BKP are not substitutes for appropriate evaluation and treatment of osteoporosis to reduce the risk of future fractures.

Coordinator-based systems for secondary prevention in fragility fracture patients

The underlying causes of incident fractures--bone fragility and the tendency to fall--remain under-diagnosed and under-treated. This care gap in secondary prevention must be addressed to minimise both the debilitating consequences of subsequent fractures for patients and the associated economic burden to healthcare systems. Clinical systems aimed at ensuring appropriate management of patients following fracture have been developed around the world. A systematic review of the literature showed that 65% of systems reported include a dedicated coordinator who acts as the link between the orthopaedic team, the osteoporosis and falls services, the patient and the primary care physician. Coordinator-based systems facilitate bone mineral density testing, osteoporosis education and care in patients following a fragility fracture and have been shown to be cost-saving. Other success factors included a fracture registry and a database to monitor the care provided to the fracture patient. Implementation of such a system requires an audit of existing arrangements, creation of a network of healthcare professionals with clearly defined roles and the identification of a 'medical champion' to lead the project. A business case is needed to acquire the necessary funding. Incremental, achievable targets should be identified. Clinical pathways should be supported by evidence-based recommendations from national or regional guidelines. Endorsement of the proposed model within national healthcare policies and advocacy programmes can achieve alignment of the objectives of policy makers, professionals and patients. Successful transformation of care relies upon consensus amongst all participants in the multi-disciplinary team that cares for fragility fracture patients.

Subtrochanteric fractures after long-term treatment with bisphosphonates: a European Society on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis, and International Osteoporosis Foundation Working Group Report

This paper reviews the evidence for an association between atypical subtrochanteric fractures and long-term bisphosphonate use. Clinical case reports/reviews and case-control studies report this association, but retrospective phase III trial analyses show no increased risk. Bisphosphonate use may be associated with atypical subtrochanteric fractures, but the case is yet unproven.

INTRODUCTION

A Working Group of the European Society on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis and the International Osteoporosis Foundation has reviewed the evidence for a causal association between subtrochanteric fractures and long-term treatment with bisphosphonates, with the aim of identifying areas for further research and providing recommendations for physicians.

METHODS

A PubMed search of literature from 1994 to May 2010 was performed using key search terms, and articles pertinent to subtrochanteric fractures following bisphosphonate use were analysed.

RESULTS

Several clinical case reports and case reviews report a possible association between atypical fractures at the subtrochanteric region of the femur in bisphosphonate-treated patients. Common features of these 'atypical' fractures include prodromal pain, occurrence with minimal/no trauma, a thickened diaphyseal cortex and transverse fracture pattern. Some small case-control studies report the same association, but a large register-based study and retrospective analyses of phase III trials of bisphosphonates do not show an increased risk of subtrochanteric fractures with bisphosphonate use. The number of atypical subtrochanteric fractures in association with bisphosphonates is an estimated one per 1,000 per year. It is recommended that physicians remain vigilant in assessing their patients treated with bisphosphonates for the treatment or prevention of osteoporosis and advise patients of the potential risks.

CONCLUSIONS

Bisphosphonate use may be associated with atypical subtrochanteric fractures, but the case is unproven and requires further research. Were the case to be proven, the risk-benefit ratio still remains favourable for use of bisphosphonates to prevent fractures.

Variation in the PTH gene, hip fracture, and femoral neck geometry in elderly women

Parathyroid hormone (PTH) is a principal regulator of calcium homeostasis. Previously, we studied single-nucleotide polymorphisms present in the major genes in the PTH pathway (PTH, PTHrP, PTHR1, PTHR2) in relation to bone mineral density (BMD) and fracture incidence. We found that haplotypes of the PTH gene were associated with fracture risk independent of BMD. In the present study, we evaluated the relationship between PTH haplotypes and femoral neck bone size. Hip structure analysis and BMD of the femoral neck was assessed by DXA in elderly women from the Malmö Osteoporosis Prospective Risk Assessment study. Data on hip fracture, sustained as a result of low trauma, after the age of 45 years were also analyzed. Haplotypes derived from six polymorphisms in the PTH locus were analyzed in 750 women. Carriers of haplotype 9 had lower values for hip geometry parameters cross-sectional moment of inertia (P = 0.029), femoral neck width (P = 0.049), and section modulous (P = 0.06), suggestive of increased fracture risk at the hip. However, this did not translate into an increased incidence of hip fracture in the studied population. Women who suffered a hip fracture compared to those who had not had longer hip axis length (HAL) (P < 0.001). HAL was not significantly different among haplotypes. Polymorphisms in the PTH gene are associated with differences in aspects of femoral neck geometry in elderly women; however, the major predictor of hip fracture in our population was HAL, to which PTH gene variation does not contribute significantly.

The non-inherited maternal HLA haplotype affects the risk for type 1 diabetes

The aim was to test the hypothesis that the human leucocyte antigen (HLA) haplotype that is not inherited from the mother, that is, the non-inherited maternal antigen (NIMA) affects the risk for type 1 diabetes (T1D). A total of 563 children with T1D and 286 non-diabetic control children from Sweden were genotyped for DRB1, DQA1 and DQB1 alleles. The frequency of positively (DR4-DQA1*0301-B1*0302 and DR3-DQA1*0501-B1*0201), negatively (DR15-DQ A1*0102-B1*0602) or neutrally (all other) T1D associated HLA haplotypes were compared between NIMA and non-inherited paternal antigen (NIPA). All comparisons were carried out between HLA-matched patients and controls. The frequency of positively associated NIMA was higher among both DR4/X-positive healthy individuals compared wit DR4/X-positive patients (P < 0.00003) and DR3/X-positive healthy individuals compared with DR3/X-positive patients (P < 0.009). No such difference was observed for NIPA. High-risk NIMA was increased compared to NIPA among healthy DR3/X- and DR4/X-positive children (P < 0.05). There was no difference in frequency of positively associated haplotypes between patient NIMA and NIPA. The NIMA but not the NIPA affects the risk for T1D, suggesting that not only the inherited but also non-inherited maternal HLA haplotypes, perhaps through microchimerism or other mechanisms, may influence the risk for the disease.

Disease activity and disability but probably not glucocorticoid treatment predicts loss in bone mineral density in women with early rheumatoid arthritis

OBJECTIVES

Osteoporosis is a known complication of rheumatoid arthritis (RA). This prospective study aimed to evaluate whether disease activity, disability, and glucocorticoid (GC) treatment in early RA were risk factors for loss of bone mineral density (BMD).

METHODS

We followed 97 women (mean age 58 years), for 24 months, with a history of RA of less than 12 months. At baseline, 77 women were receiving standard treatment with disease-modifying antirheumatic drugs (DMARDs) and 20 were receiving no treatment. Risk factors for osteoporosis were recorded. Disease activity score (DAS28), Health Assessment Questionnaire (HAQ) score, and medications were registered at baseline and every 6 months and calculated as areas under the curve (AUCs). Femoral neck and lumbar spine BMD were measured at baseline and after 2 years and compared to BMD in age- and gender-matched controls. Risk factors were analysed by linear regression models.

RESULTS

BMD loss was comparable to that of age-matched women in both the lumbar spine and the femoral neck, although neither was significantly different from baseline. In multivariate analyses the AUC for DAS28 was an independent predictor of changes in lumbar spine BMD (p = 0.003) and that for HAQ of changes in femoral neck BMD (p = 0.018). GC use was not an overall predictor of BMD loss.

CONCLUSION

BMD loss was predicted by high disease activity and disability but not by GC treatment. With the DMARD, GC, hormone replacement therapy (HRT), and bisphosphonate treatment strategies used during the study period, the general outcome seems favourable concerning loss of BMD in patients with early RA.

Post-fracture management of patients with hip fracture: a perspective

BACKGROUND

Hip fracture creates a worldwide morbidity, mortality and economic burden. After surgery, many patients experience long-term disability or die as a consequence of the fracture. A fracture is a major risk factor for a subsequent fracture, which may occur within a short interval.

METHODS

A literature search on post-fracture management of patients with hip fracture was performed on the Medline database. Key experts convened to develop a consensus document.

FINDINGS

Management of hip-fracture patients to optimize outcome after hospital discharge requires several stages of care co-ordinated by a multidisciplinary team from before admission through to discharge. Further studies that specifically assess prevention and post-fracture management of hip fracture are needed, as only one study to date has assessed an osteoporosis medication in patients with a recent hip fracture. Proper nutrition is vital to assist bone repair and prevent further falls, particularly in malnourished patients. Vitamin D, calcium and protein supplementation is associated with an increase in hip BMD and reduction in falls. Rehabilitation is essential to improve functional disabilities and survival rates. Fall prevention and functional recovery strategies should include patient education and training to improve balance and increase muscle strength and mobility. Appropriate management can prevent further fractures and it is critical that high-risk patients are identified and treated. To foster this process, clinical pathways have been established to support orthopaedic surgeons.

CONCLUSION

Although hip fracture is generally associated with poor outcomes, appropriate management can ensure optimal recovery and survival, and should be prioritized after a hip fracture to avoid deterioration of health and prevent subsequent fracture.

Large-scale association study between two coding LRP5 gene polymorphisms and bone phenotypes and fractures in men

Herein we investigated the association between polymorphisms in the LRP5 gene and bone phenotypes and fractures in three large male cohorts based on the rationale that mutations in LRP5 cause severe bone phenotypes. Results showed an association of the Val667Met SNP with spine BMD in 3,800 young and elderly men.

INTRODUCTION

The low-density lipoprotein receptor-related protein 5 (LRP5)-Wnt signalling system is of importance for regulating osteoblastic activity, which became clear after findings that inactivating mutations in LRP5 cause osteoporosis. The overall aim of this study was to investigate the association between polymorphisms in the LRP5 gene and bone mineral density (BMD) in three large cohorts of young and elderly men.

METHODS

The cohorts used were MrOS Sweden (n = 3014, aged 69-81 years) and MrOs Hong Kong (n = 2000, aged > 65 years) and the Swedish GOOD study (n = 1068, aged 18-20 years). The polymorphisms Val667Met and Ala1330Val were genotyped using a TaqMan assay.

RESULTS

When combining the data from the Swedish cohorts in a meta-analysis (n = 3,800), men carrying the 667Met-allele had 3% lower BMD at lumbar spine compared with non-carriers (p < 0.05). The Val667Met SNP was not polymorphic in the Hong Kong population and thus were not included. There were no associations between the Ala1330Val SNP and bone phenotypes in the study populations. No associations between the LRP5 polymorphisms and self-reported fractures were seen in MrOs Sweden.

CONCLUSIONS

Results from these three large cohorts indicate that the Val667Met polymorphism but not the Ala1330Val contributes to the observed variability in BMD in the Swedish populations.

Genetic variation in the PTH pathway and bone phenotypes in elderly women: evaluation of PTH, PTHLH, PTHR1 and PTHR2 genes

INTRODUCTION

Parathyroid hormone (PTH) is a key regulator of calcium metabolism. Parathyroid hormone-like hormone (PTHrP) contributes to skeletal development through regulation of chondrocyte proliferation and differentiation during early bone growth. Both PTH and PTHrP act through the same receptor (PTHR1). A second receptor, PTHR2, has been identified although its function is comparatively unknown. PTH hyper-secretion induces bone resorption, whereas intermittent injection of PTH increases bone mass. To explore the effects of genetic variation in the PTH pathway, we have analysed variations in PTH, PTHLH, PTHR1 and PTHR2 in relation to bone mass and fracture incidence in elderly women.

MATERIALS AND METHODS

This study includes 1044 elderly women, all 75 years old, from the Malmö Osteoporosis Prospective Risk Assessment study (OPRA). Single nucleotide polymorphisms (SNPs) from 4 genes and derived haplotypes in the PTH signaling pathway were analysed in 745-1005 women; 6 SNPs in the PTH gene and 3 SNPs each in the PTHLH, PTHR1 and PTHR2 genes were investigated in relation to BMD (assessed at baseline), fracture (434 prevalent fractures of all types over lifetime, self-reported and 174 incident fractures up to 7 years, X-ray verified) and serum PTH.

RESULTS AND CONCLUSION

Individually, SNPs in the 4 loci did not show any significant association with BMD. Neither were PTHLH, PTHR1 and PTHR2 polymorphisms associated with fracture. Three of 5 common haplotypes, accounting for >98% of alleles at the PTH locus, were identified as independent predictors of fracture. Haplotype 9 (19%) was suggestive of an association with fractures of any type sustained during lifetime (p=0.018), with carriers of one or more copies of the haplotype having the lowest incidence (p=0.006). Haplotypes 1 (13%) and 5 (37%) and 9 were suggestive of an association with fractures sustained between 50 and 75 years (p=0.02, p=0.013 and p=0.034). Carriers of haplotypes 1 and 5 were more likely to suffer a fracture (haplotype 1, p=0.045; haplotype 5, p=0.008). We conclude, that while further genotyping across the gene is recommended, in this cohort of elderly Swedish women, polymorphisms in PTH may contribute to the risk of fracture through mechanisms that are independent of BMD.

Rates of fracture in participants and non-participants in the Osteoporosis Prospective Risk Assessment study

We invited 1604 randomly selected women, all 75 years of age, to participate in a study on the risk factors for fracture. The women were divided into three groups consisting of 1044 (65%) who attended the complete study, 308 (19%) respondents to the study questionnaire only and 252 (16%) who did not respond. The occurrence of the life-time fracture was ascertained from radiological records in all groups and by questionnaires from the attendees and respondents. According to the radiological records, fewer of the questionnaire respondents (88 of 308, 28.6%) and non-respondents (68 of 252, 27%) had sustained at least one fracture when compared with the attendees (435 of 1044, 41.7%; chi-squared test, p < 0.001). According to the questionnaire, fewer of the respondents (96 of 308, 31.1%) had sustained at least one previous fracture when compared with the attendees (457 of 1044, 43.7%; chi-squared test, p < 0.001). Any study concerning the risk of fracture may attract those with experience of a fracture which explains the higher previous life-time incidence among the attendees. This factor may cause bias in epidemiological studies.

The association between hyperglycemia and fracture risk in middle age. A prospective, population-based study of 22,444 men and 10,902 women

AIMS

Type 1 diabetes mellitus is associated with increased fracture risk, whereas the risk associated with type 2 diabetes is less obvious. Elevated fasting blood glucose and high 2-h glucose during an oral glucose tolerance test indicate impaired glucose tolerance or diabetes. The associations among fasting blood glucose, 2-h glucose, and the risk of fracture were investigated.

METHODS

The Malmö Preventive Project consists of 22,444 men (44+/-6.6 yr) and 10,902 women (50+/-7.4 yr), with a follow-up of 19 yr (+/-3.9) and 15 yr (+/-4.5) for incident fractures. Baseline assessment included multiple examinations and lifestyle information. A logistic regression model was used. Adjustments were made for age, body mass index (BMI), and smoking.

RESULTS

Low-energy fractures were recorded in 1246 men and 1236 women. A 2-h glucose measurement between 4.3 and 6.2 mmol/liter in men (second and third quartile), and above 6.5 mmol/liter in women (third and fourth quartile), adjusted for age, BMI, and smoking, was significantly associated with a decreased risk of multiple fractures, in men [odds ratios (ORs) 0.57-0.71] and women (ORs 0.38-0.66). In women, a 2-h glucose measurement above 7.5 mmol/liter was associated with a decreased risk of osteoporotic fractures (OR 0.57, 95% confidence interval 0.44-0.74).

CONCLUSIONS

In middle-aged men and women, elevated 2-h glucose levels were associated with decreased risks of multiple and osteoporotic fractures, independent of age, BMI, and smoking. A high 2-h glucose level is characterized by peripheral insulin resistance with a high insulin level. Our findings indirectly suggest a positive effect on bone from hyperglycemia.

Islet cell autoantibody levels after the diagnosis of young adult diabetic patients

AIMS

The aim was to determine the course of islet cell antibodies [glutamate decarboxylase (GADA), tyrosine phosphatase-like islet antigen 2 (IA-2A) and islet cell (ICA)] after the diagnosis of the diabetic patient.

METHODS

The Diabetes Incidence Study in Sweden (DISS) attempted to prospectively enrol all newly diagnosed diabetic patients aged 15-34 years during 1992 and 1993. C-peptide and autoantibody levels were determined from venous blood samples at diagnosis and again at yearly intervals for 6 years.

RESULTS

After the first year, the odds of remaining GADA positive decreased by 9% per year [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.85-0.96] while the mean GADA index remained unchanged ( = 0.8, P = 0.37). There was no change in the percentage of subjects testing IA-2A positive after the first year ( = 0.1, P = 0.75). However, the mean index decreased 0.04 per year (95% CI: 0.03-0.05)-a 7.9% decline (95% CI: 5.4-10.4%). The odds of a subject testing positive for ICA decreased by 24% per year (OR = 0.76, 95% CI = 0.70-0.82). The mean ICA levels decreased 0.75 per year (95% CI: 0.66-0.84)-a 16.4% decline (95% CI: 14.1-18.6%). The rate of change in titres for all three autoantibodies was independent of gender, human leucocyte antigen genotype and C-peptide status.

CONCLUSIONS

GADA levels remained high while ICA levels declined. In contrast to a previous study, we found that the proportion of IA-2A subjects remaining positive did not decrease after the first year, while the average index decreased slightly.

Risk factors for fragility fracture in middle age. A prospective population-based study of 33,000 men and women

The incidence of fragility fractures begins to increase in middle age. We investigated prospectively risk factors for low-energy fractures in men and women, and specifically for forearm, proximal humerus, vertebral, and ankle fractures. The population-based Malmö Preventive Project consists of 22,444 men and 10,902 women, mean age 44 and 50 years, respectively, at inclusion. Baseline assessment included multiple examinations and lifestyle information. Mean follow-up was 19 and 15 years for men and women, respectively, regarding incident fractures. Fractures were ascertained from radiographic files. At least one low-energy fracture occurred in 1,262 men and 1,257 women. In men, the risk factors most strongly associated with low-energy fractures were diabetes [relative risk (RR) 2.38, confidence interval (CI) 95% 1.65-3.42] and hospitalization for mental health problems (RR 1.92, CI 95% 1.47-2.51). Factors associated with mental health and lifestyle significantly increased the fracture risk in most of the specific fracture groups: hospitalizations for mental health problems (RR 2.28-3.38), poor appetite (RR 3.05-3.43), sleep disturbances (RR 1.72-2.95), poor self-rated health (RR 1.80-1.83), and smoking (RR 1.70-2.72). In women, the risk factors most strongly associated with low-energy fractures were diabetes (RR 1.87, CI 95% 1.26-2.79) and previous fracture (RR 2.00, CI 95% 1.56-2.58). High body mass index (BMI) significantly increased the risk of proximal humerus and ankle fractures (RR 1.21-1.33) while, by contrast, lowering the risk of forearm fractures (RR 0.88, CI 95% 0.81-0.96). Risk factors for fracture in middle-aged men and women are similar but with gender differences for forearm, vertebral, proximal humerus, and hip fracture whereas risk factors for ankle fractures differ to a certain extent. The risk-factor pattern indicates a generally impaired health status, with mental health problems as a major contributor to fracture risk, particularly in men.

Increased bone density and decreased bone turnover, but no evident alteration of fracture susceptibility in elderly women with diabetes mellitus

Bone density, bone turnover and fracture susceptibility were evaluated in 1,132 randomly recruited women, all 75 years old. Seventy-four of the women had diabetes, while 1,058 women did not. Areal bone mineral density (aBMD) of the hip and lumbar spine was investigated by dual energy X-ray absorptiometry (DXA), and bone mass of the calcaneus was measured by ultrasound. Urinary deoxypyridinoline/creatinine (U-DPD/Crea) and serum C-terminal cross-linked telopeptide of type 1 collagen (S-CTX) were assessed as markers of bone resorption. Serum bone-specific alkaline phosphatase (S-bone ALP) and serum osteocalcin (S-OC) were assessed as markers of bone formation. Also, serum 25(OH) vitamin D and serum parathyroid hormone (S-PTH) were assessed. Fracture susceptibility was evaluated retrospectively and prospectively for up to 6.5 years. In diabetic women, the aBMD of the femoral neck was 11% higher (p<0.001), and BMD of the lumbar spine was 8% higher (p=0.002) than in non-diabetic women. There was no difference in bone mass by ultrasound of the calcaneus. Women with diabetes had higher BMD of the femoral neck (p<0.001) and lumbar spine (p=0.03) also after correction for differences in body weight. In diabetic women, U-DPD/Crea, S-CTX, and S-OC were decreased when compared with non-diabetic women (p=0.001 or less). After correction for covariance of body weight and plasma creatinine, S-CTX (p<0.001) and S-OC (p<0.001) were still lower in the diabetic women. Diabetic patients had hypovitaminosis D (p=0.008), a difference explained by differences in time spent outdoors and body weight. S-PTH did not differ between the groups. Women with diabetes had no more lifetime fractures (52%) than women without diabetic disease (57%), (p=0.31). This study shows that elderly women with diabetes and without severe renal insufficiency have high bone mass and low bone turnover. The high bone mass and low bone turnover is not likely to have a strong influence on fracture susceptibility.

Increased risk of diabetes among relatives of female insulin-treated patients diagnosed at 15-34 years of age

AIMS

This study aimed to determine the risk of developing diabetes among relatives of patients diagnosed between 15 and 34 years of age who were treated with insulin. Our second aim was to determine whether there was a difference in risk of diabetes between relatives of male and female patients.

METHODS

A questionnaire was sent to patients in the Diabetes Incidence Study in Sweden registry diagnosed between 1983 and 1993 to determine the presence of first-degree relatives with diabetes.

RESULTS

In 3087 index patients treated with insulin, 17.8% (95% confidence interval 16.5, 19.2) had a first-degree relative (excluding offspring) treated with insulin, the frequency being higher in female (19.8%) than in male (16.5%, P = 0.018) patients. A total of 10.7% had a parent treated with insulin. The prevalence of insulin-treated diabetes was higher among parents of female (12.5%) than of male (9.5%), insulin-treated index patients (P = 0.0068). A similar difference was observed using life table analysis (P = 0.0025), which also showed that the risk by 63 years of age was 7.6% for parents of female and 4.9% for parents of male insulin-treated index patients. In insulin-treated index patients, 8.4% had a sibling with insulin-treated diabetes.

CONCLUSIONS

We conclude that the risk for relatives of women with insulin-treated diabetes was higher than for relatives of insulin-treated male patients. We suggest that greater genetic susceptibility is required for females compared with males in the 15-34 age group in order to develop diabetes and hence females might carry more diabetes genes since more of their relatives also develop diabetes.

Association between 25-hydroxy vitamin D levels, physical activity, muscle strength and fractures in the prospective population-based OPRA Study of Elderly Women

Vitamin D supplements have been used to prevent fractures. The effect may be mediated through increased bone mass, but also through reduced falling propensity. The aim of this study was to evaluate the association between 25-hydroxy vitamin D levels (25OHD), fall-associated variables (including tests of functional performance), and fracture in ambulatory women. At baseline 25OHD was measured in 986 women. Fall-associated variables were investigated at baseline. Fractures were recorded during a 3-year follow-up. Four percent of the women had 25OHD levels below 20 ng/ml (50 nmol/l), and 26% had 25OHD levels below 30 ng/ml (75 nmol/l). 25OHD correlated with gait speed (r =0.17, P <0.001), the Romberg balance test (r =0.14, P <0.001), self-estimated activity level (r =0.15, P <0.001), and thigh muscle strength (r =0.08, P =0.02). During the 3-year follow-up, 119 out of the 986 women sustained at least one fracture. The Cox proportional hazard ratio (HR) (95% confidence interval) for sustaining a fracture during the follow-up was 2.04 (1.04-4.04) for the group of women with 25OHD below 20 ng/ml, in which 9 out of 43 women sustained a fracture. Thirty-two of the 256 women with 25OHD levels below 30 ng/ml sustained a fracture during the follow-up, with a non-significant HR of 1.07 (1.07-1.61). This cohort of elderly, ambulatory women had a high mean 25OHD. A low 25OHD was associated with inferior physical activity level, gait speed and balance. A 25OHD level below 30 ng/ml was not associated with an increased risk of fractures in this study. However, a subgroup of women with 25OHD levels below 20 ng/ml had a tendency to an increased risk of fractures, which may be associated with an inferior physical activity and postural stability.

Global core recommendations for a musculoskeletal undergraduate curriculum

OBJECTIVE

To develop core recommendations for the learning outcomes of an undergraduate curriculum in musculoskeletal conditions for any parts of the globe.

METHODS

Recommendations were developed by wide consultation with experts in orthopaedics, rheumatology, osteoporosis, and rehabilitation from all parts of the world who had interest and experience in these specialties, with the support of international and national societies. All possible knowledge, skills, and attitudes that might be of relevance to musculoskeletal conditions were initially considered and then reduced to those considered essential for all doctors.

RESULTS

The recommendations focus on (a) basic skills to assess and diagnose musculoskeletal problems; (b) the competency to assess specific common or urgent musculoskeletal problems; (c) the theoretical background of the conditions and their management; and (d) the core knowledge necessary to support diagnosis and management, including basic sciences. At the end of the course, all students should be able to differentiate normal from abnormal locomotor symptoms in a patient, determine the relevant investigations and interpret the results, formulate a limited differential diagnosis, recognise the impact of the problem on the individual patient, and make an appropriate management plan.

CONCLUSIONS

The recommendations set global standards for the minimum level of competence in managing patients with musculoskeletal problems. They define what all doctors should know when graduating from medical school, regardless of further specialisation. They are intended to form the basis of a curriculum for a musculoskeletal course and can be adapted for any medical school in any country throughout the world.

Association of the collagen type 1 (COL1A 1) Sp1 binding site polymorphism to femoral neck bone mineral density and wrist fracture in 1044 elderly Swedish women

Identification of risk factors for osteoporosis has been essential for understanding the development of osteoporosis and related fragility fractures. A polymorphism of the binding site for the transcription factor Sp1 of the collagen I alpha 1 gene (COLIA1) has shown an association to bone mass and fracture, but the findings have not been consistent, which may be related to population differences. The Sp1 polymorphism was determined in 1044 women, all 75 years old, participating in the population-based Osteoporosis Prospective Risk Assessment study in Malmö (OPRA). Bone mineral density, heel ultrasound and all previous fractures were registered. BMD was 2.7% lower in the femoral neck in women carrying at least one copy of the "s" allele ( P = 0.027). There was no difference in bone mass at any other site, weight, BMI or age at menopause. Women with a prevalent wrist fracture (n = 181) had an increased presence of the "s" allele. The odds ratio for prevalent wrist fracture was 2.73 (95% CI 1.1-6.8) for the ss homozygotes and 1.4 (95% CI 1.0-2.0) for the Ss heterozygotes when compared with the SS homozygotes. In conclusion, in this large and homogeneous cohort of 75-year-old Swedish women, there was an association among the Sp1 COLIA1 polymorphism, bone mass, and fracture. The presence of at least one copy of the "s" allele was associated with lower femoral neck BMD and previous wrist fracture and in addition, it was related to an increased risk for wrist fracture.

Single nucleotide polymorphisms in the human gene for osteoprotegerin are not related to bone mineral density or fracture in elderly women

Osteoprotegerin (OPG), a secreted member of the tumor necrosis factor receptor family, is a potent inhibitor of osteoclast activation and differentiation. In animal models OPG prevents bone loss, and in humans bone resorption can be reduced by injections of OPG. OPG may also play a role in cardiovascular disease since mice lacking the OPG gene display arterial calcification. In a screening effort of the OPG gene, we recently discovered a single nucleotide polymorphism in the promoter region of OPG (T950C), and reported an association with vascular morphology and function in 59 healthy individuals. Due to the pronounced effect of OPG on bone turnover, the present study was conducted to investigate whether OPG polymorphisms are also associated with bone mineral density or with fracture. The relationship between single nucleotide polymorphisms in the promoter region of OPG (T950C) and the first intron (C1217T), and bone mineral density, measured by DXA in the hip or spine or ultrasound of the heel, was investigated in the Malmö OPRA-study of 1044 women, all 75 years old. The possible relation to fracture incidence was also analyzed. Among the 858 and 864 individuals respectively, genotyped, no significant associations between the investigated single nucleotide polymorphisms and bone mineral density measurements (T950C P = 0.50-0.64, C1217T P = 0.51-1.00), quantitative ultrasound measurements of the calcaneus, or fractures (T950C P = 0.61-0.66, C1217T P = 0.14-0.33) were found. Thus, our results show that polymorphisms in the OPG gene, one of which has previously been found to be associated with cardiovascular morphology and function, are not associated with bone mineral density in elderly Swedish women.

Influence of muscle strength, physical activity and weight on bone mass in a population-based sample of 1004 elderly women

High physical activity level has been associated with high bone mass and low fracture risk and is therefore recommended to reduce fractures in old age. The aim of this study was to estimate the effect of potentially modifiable variables, such as physical activity, muscle strength, muscle mass and weight, on bone mass in elderly women. The influence of isometric thigh muscle strength, self-estimated activity level, body composition and weight on bone mineral density (dual energy X-ray absorptiometry; DXA) in total body, hip and spine was investigated. Subjects were 1004 women, all 75 years old, taking part in the Malmö Osteoporosis Prospective Risk Assessment (OPRA) study. Physical activity and muscle strength accounted for 1-6% of the variability in bone mass, whereas weight, and its closely associated variables lean mass and fat mass, to a much greater extent explained the bone mass variability. We found current body weight to be the variable with the most substantial influence on the total variability in bone mass (15-32% depending on skeletal site) in a forward stepwise regression model. Our findings suggest that in elderly women, the major fracture-preventive effect of physical activity is unlikely to be mediated through increased bone mass. Retaining or even increasing body weight is likely to be beneficial to the skeleton, but an excess body weight increase may have negative effects on health. Nevertheless, training in elderly women may have advantages by improving balance, co-ordination and mobility and therefore decreasing the risk of fractures.

Effect of previous and present physical activity on bone mass in elderly women

The importance of a physically active lifestyle as a preventive measure for maintaining bone mass is often stressed. The aim of this study was to evaluate the effect of everyday physical activity on bone mass from young adulthood to old age in 75-year-old women. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry technique in total body, hip (femoral neck and trochanter), and spine (LII-LIV) in a population-based cohort of 995 women, all 75 years old. Each woman responded to a questionnaire giving an estimate of the previous and present physical activity level at work and leisure time from youth and up to the present age of 75 years. No correlations were found between the different estimates of physical activity level and BMD. In a multiple regression analysis the different estimates of physical activity level did not have any combined effect on BMD in any of the skeletal regions measured; neither did the physical activity, previous or present, differ when the subgroup of women with a BMD in the highest quintile at all sites was compared with women with a BMD in the lowest quintile. The activity level in the various areas of life did not correlate to each other indicating that few women had chosen a generally active vs non-active lifestyle. A hypothetical positive effect on bone by one activity could therefore be diminished by another. The answer alternatives were mostly not normally distributed, which could also affect the results, making it difficult to identify women with extremely high or low physical activity level. In conclusion, the results from this study of randomly selected elderly women cannot confirm an effect of previous and present everyday physical activity on bone mass. Neither was it possible to find an effect of physical activity in those women with the highest BMD at all sites, suggesting that other factors are of greater importance for maintaining bone mass in elderly women.

Role of biochemical markers in the management of osteoporosis

Several serum and urine biochemical markers of bone resorption and formation have been developed. Biochemical bone markers have been used as intermediate end-points in all major studies of anti-osteoporotic therapies. Bone resorption markers, in particular, may add an independent, predictive value to the assessment of bone loss and fracture risk. There are also potential advantages in monitoring anti-osteoporotic treatment in the short-term in addition to bone densitometry, to rapidly identify non-responders to therapy, or non-compliance. Despite these recent advances, until now bone markers have simply been very useful research tools, with their clinical utility being limited by intra-individual and diurnal variability. However, the probability of the true bone mineral density response to hormone replacement therapy for the individual patient may be predicted using algorithms based on a spectrum of cut-off bone marker levels with varying false positive and negative rates. Thus, the transition of biochemical bone markers into everyday clinical practice may be rapidly approaching.

Bone loss following tibial osteotomy: a model for evaluating post-traumatic osteopenia

The reduced bone mineral density (BMD) found in patients with fractures may, in part, follow rather than precede the fracture. We studied the magnitude and reversibility of bone loss in the 15 months following osteotomy in 21 men and 5 women with localized medial arthritis of the knee. BMD (mean +/- SD), measured using dual-energy X-ray absorptiometry, decreased by a maximum of 35 +/- 21% in the mid-diaphysis of the affected tibia at 9 months after surgery (p < 0.001). At 15 months, reversal of bone loss in non-fractured bones was incomplete; the remaining deficit was 20 +/- 27% relative to baseline (p < 0.001). Maximum bone loss occurred at 9 months at the total body (5 +/- 2%), spine (15 +/- 17%) and at Ward's triangle of the proximal femur of the unoperated limb (10 +/- 17%) (all p < 0.01). In summary, post-traumatic bone loss is region-specific with incomplete reversibility, at least after about 15 months. Deficits in BMD in cross-sectional studies of patients with fractures, held to be responsible for the bone fragility, may, in part, follow rather than precede the fracture.

The proportion of carboxylated to total or intact osteocalcin in serum discriminates warfarin-treated patients from control subjects

We assessed the serum concentration of gamma-carboxylated osteocalcin (OC), total OC, and full-length OC in a clinical setting of 37 patients on continuous warfarin treatment (international normalized ratio 2.0-3.8). A comparison was done with the results from 30 untreated age-matched controls. Four monoclonal antibodies, previously generated and characterized as to their ability to recognize different human OC forms and fragments, were used in three two-site immunofluorometric assays. The warfarin-treated patients had significantly lower levels of carboxylated OC 4.9 +/- 3.8 (+/- 1 SD) ng/ml compared with the controls 13.1 +/- 9.7 (p < 0.0001). There was no difference in the levels of total OC or full-length OC between the two groups of patients. A strong correlation was found between the serum concentration of carboxylated OC and total OC, both for the warfarin-treated patients (r = 0.98) and for the controls (r = 0.99). There was a distinct cut-off level at 0.80, in the quotient carboxylated OC/total OC, at which all warfarin-treated patients fell below and all controls above this level. Hence, the concentration or ratio of serum gamma-carboxylated OC in clinical settings such as warfarin-treated patients could be measured using two-site immunoassays.

Effects of short-term calcium depletion and repletion on biochemical markers of bone turnover in young adult women

The skeletal responses to calcium depletion and repletion in rodents have been well characterized, but those in humans are poorly understood. The present study sought to evaluate the effects of short term dietary calcium depletion and repletion on biochemical markers of bone turnover in 15 young Caucasian women (age, 21-30 yr). The study contained 3 phases: 1) 5 days of a regular diet containing more than 800 mg/day calcium to establish baseline values (baseline phase), 2) 22 days of a restricted diet containing less than 300 mg/day calcium (depletion phase), and 3) 7 days of a normal diet containing more than 800 mg/day calcium (repletion phase). Serum and urine samples were obtained from each subject during the baseline phase; on the first, second, and last days of the depletion phase; and on the third and last days of the repletion phase. Serum levels of calcium, PTH, 1,25-dihydroxyvitamin D3, osteocalcin, and C-terminal type I procollagen peptide (PICP) and urinary levels of calcium and deoxypyridinoline were determined. Serum and urinary calcium levels were significantly reduced, and serum PTH and 1,25-dihydroxyvitamin D3 levels were markedly increased during depletion. These changes were completely reversed after 1 week of repletion. Depletion also rapidly and significantly increased the urinary deoxypyridinoline level, indicating increased bone resorption. The increase also returned rapidly to baseline upon repletion. Calcium depletion had contrasting effects on bone formation markers; whereas depletion significantly reduced the serum PICP level, it significantly increased serum osteocalcin level. Past histomorphometric studies in rodents indicated that the number of mature but inactive osteoblasts was increased during depletion despite an inhibition of bone formation. Thus, it is speculated that although the reduction in serum PICP reflected the depletion-associated inhibition of bone formation, the increase in serum osteocalcin could represent this depletion-related increase in osteoblast number. During repletion, serum osteocalcin remained elevated above baseline. PICP recovered from its depressed level and increased above baseline, a finding consistent with past histomorphometric findings of increased bone formation during repletion. In summary, this study confirms that 1) a short calcium depletion period produces calcium stress in young women, which leads to rapid stimulation of bone resorption and inhibition of bone formation; and 2) a subsequent calcium repletion period could lead to a compensatory increase in bone formation. In conclusion, the skeletal responses to calcium depletion/ repletion in young women may be similar to those in rodents.

Effects of calcium depletion and repletion on serum insulin-like growth factor I and binding protein levels in weanling rats

Previous studies in a weanling rat model indicated that dietary calcium depletion not only stimulated osteoclastic resorption but also inhibited bone formation. The present study sought to test whether the depletion-associated inhibition of bone formation is related to a reduction in serum insulin-like growth factor-I (IGF-I) and/or an increase in its binding proteins (IGFBPs). Twenty male weanling rats were divided into two weight-matched groups. The study group was subjected to a semisynthetic diet deficient in calcium (0.02% calcium) for 28 days, while the control group was pair-weighed on the same diet but containing 0.62% calcium. After the depletion phase, all rats were fed the same calcium-containing diet for an additional 14 days. Serum samples were obtained from each animal on a weekly basis and assayed for IGF-I and IGFBPs. During depletion, there was no statistically significant difference in serum IGF-I level between the study group and the control group. In contrast, the study group showed a statistically significant increase in several serum IGFBPs with apparent molecular size of 30-38 kD (IGFBP-3), 26-28 kD (IGFBP-1, -2, -5, and/or -6), and 24-25 kD (IGFBP-4), respectively, compared to the control group. There was no difference in nutritional intakes between the two groups of rats during depletion. During repletion, there was also no significant difference in serum IGF-I level between the control and study group. However, during the first 7 days of repletion, serum IGFBP-3 and the 26-28 kD IGFBP of the study group was significantly less than those of the control group, which then returned to the control level after 2 weeks of repletion. In summary: (1) calcium depletion in weanling rats increased several serum IGFBPs without an effect on IGF-I; and (2) calcium repletion induced an acute reduction in serum IGFBP-3. In conclusion, these findings represent the first evidence that the depletion-related inhibition of bone formation in the rat may be associated with an increase in several serum IGFBPs, which may act to inhibit the osteogenic actions of IGFs.

Assessment of biochemical markers of bone metabolism in relation to the occurrence of fracture: a retrospective and prospective population-based study of women

We have in a population-based setting evaluated biochemical markers of bone metabolism in 328 women, aged 40-80 years, and related it to contents of bone mineral measurements and the retrospective and prospective presence of fracture. The participants were recruited from the city population files. Serum samples for analysis of osteocalcin (Oc), procollagen I carboxy-terminal extension peptide (PICP), and carboxy-terminal telopeptide of type I collagen (ICTP) were taken, and forearm bone mineral content (BMC) was measured by single photon absorptiometry (SPA). Fracture history was recorded, and the information was verified and supplemented from both radiologic and orthopedic files. Five years later the registration of fractures was repeated. At the initial investigation, Oc was 23% lower in women who had sustained a fracture (n = 37) within 6 years before measurement (6.3 +/- 3.6 microgram/l vs 8.2 +/- 4.2 microgram/l (p = 0.006)), after adjusting for age and BMC difference. PICP and ICTP were not different from values in the women without fracture. However, in women aged 70-80 years with a fracture sustained during the previous 6 years, PICP was lower (128 +/- 32 microgram/l vs 144 +/- 34 microgram/l, p = 0.046). Oc and ICTP were significantly correlated to age and BMC (Oc-age r = 0.36, Oc-BMC r = -0.31, ICTP-age r = 0.44, ICTP-BMC r = -0.24). The correlations of PICP were weaker. Prospectively, logistic regression gave an odds ratio (OR) of 1.8 (p = 0.015) for a low PICP and fracture susceptibility, at a change of 1 SD, independent of age and BMC. In the age bracket 70-80, the odds ratio was 2.4 (p = 0.036). The odds ratio for ICTP, independent of age and BMC, was 1.9 (P = 0.043) for 1 SD decrease and subsequent fracture risk. We concluded that women who had sustained at least one recent fracture had an altered bone turnover with decreased bone formation but an unaltered resorption. Women with retrospectively registered fractures also sustained subsequent fractures. A decrease from the mean of the collagen markers PICP and ICTP was associated with an increased risk for future fracture. Utilizing these biochemical markers of bone metabolism in a female population, PICP and ICTP had a similar influence on the risk of future fracture as forearm BMC (OR = 1.6, p = 0.03).

Serum osteocalcin increases during fracture healing in elderly women with hip fracture

The purpose of this study was to define the bone metabolic properties during the postfracture period in elderly women with hip fracture. Osteocalcin (Oc), a marker of bone formation, was measured in 58 women with hip fracture (77 +/- 7 years) admitted to the hospital from their own homes. Serum samples were taken on average 5 h (range 1-21) from fracture and at follow-up, on average 4.6 months later. Comparison was made with 58 age-matched (79 +/- 5 years) women. Women with hip fracture had initially 30% lower Oc levels compared to the controls (p = 0.0001). The Oc level was independent of time elapsed from trauma, within 18 h, after which the level further decreased. At follow-up, Oc showed a 44% increase (p = 0.0001) and had reached the level of the controls, but not beyond it. A concomitant, but less marked increase was noted for alkaline phosphatase (ALP) (p = 0.0001). We conclude that although the bone formation, as assessed by Oc, is apparently lower in elderly women who sustain a hip fracture, the ability to induce a fracture response, with an increased bone turnover during fracture healing is intact. Subsequently, it is essential that a time perspective is applied, as the bone metabolic changes in patients having sustained a fracture are related to the time elapsed from fracture.

Migration of the Charnley stem in rheumatoid arthritis and osteoarthritis. A roentgen stereophotogrammetric study

Migration of 65 Charnley stems implanted with modern cementing techniques was studied by roentgen stereophotogrammetry. There were 25 patients with rheumatoid arthritis (RA) and 40 with osteoarthritis (OA) followed up for two years. In 43 cases a bone sample for histomorphometric analysis was obtained from the femur during the operation. In 22 cases the mean subsidence of the prosthetic head was 0.40 mm and in 20 the mean posterior migration was 1.25 mm. There was no difference in migration between the two diagnostic groups (p = 0.8) after adjusting for variations in gender, age and weight. Male gender was associated with increased subsidence (p = 0.006). Histological examination showed that the RA series had more osteoid surface (p = 0.04), but neither this, nor any of the other histomorphometric variables, influenced migration. These results suggest that, unlike the acetabular socket, the cemented Charnley femoral component is equally secure in osteoarthritis and in rheumatoid arthritis, and that its initial fixation is not influenced by the quality of the local cancellous bone. Our results provide data with which the early performance of new prosthetic designs and fixation methods can be compared.

Migration of the Charnley stem in rheumatoid arthritis and osteoarthritis. A roentgen stereophotogrammetric study

Migration of 65 Charnley stems implanted with modern cementing techniques was studied by roentgen stereophotogrammetry. There were 25 patients with rheumatoid arthritis (RA) and 40 with osteoarthritis (OA) followed up for two years. In 43 cases a bone sample for histomorphometric analysis was obtained from the femur during the operation. In 22 cases the mean subsidence of the prosthetic head was 0.40 mm and in 20 the mean posterior migration was 1.25 mm. There was no difference in migration between the two diagnostic groups (p = 0.8) after adjusting for variations in gender, age and weight. Male gender was associated with increased subsidence (p = 0.006). Histological examination showed that the RA series had more osteoid surface (p = 0.04), but neither this, nor any of the other histomorphometric variables, influenced migration. These results suggest that, unlike the acetabular socket, the cemented Charnley femoral component is equally secure in osteoarthritis and in rheumatoid arthritis, and that its initial fixation is not influenced by the quality of the local cancellous bone. Our results provide data with which the early performance of new prosthetic designs and fixation methods can be compared.

Micromotion of the acetabular component and periacetabular bone morphology

The quality of the periacetabular bone might be an explanation for the increase in the rate of socket loosening seen radiographically in patients with rheumatoid arthritis as compared with patients with osteoarthrosis. Early implant micromotion, as measured by roentgen stereophotogrammetric analysis, is of predictive value with regard to long time retention. For uncemented porous sockets, the initial fixation might be decisive for the degree of bone ingrowth. Roentgen stereophotogrammetry was used to study cemented Charnley acetabular components in 32 hips with rheumatoid arthritis and 30 hips with osteoarthrosis, and uncemented Harris-Galante acetabular components in 19 hips with osteoarthrosis. Micromotions as long as 24 months after surgery were related to the periacetabular cancellous bone quality, as assessed by histomorphometric methods from samples taken during surgery. Acetabular components migrated more in hips with rheumatoid arthritis than in those with osteoarthrosis (p < 0.04). Hips with rheumatoid arthritis had approximately 4 times more nonmineralized bone than hips with osteoarthrosis (p < 0.0002). However, within each diagnostic group, no correlation was found between migration and the degree of mineralization (r < or = 0.24, p > or = 0.07). Migration of uncemented acetabular components did not correlate with the histomorphometric variables (r < or = 0.20, p > or = 0.42). Histomorphologic characteristics of the periacetabular trabecular bone do not seem to be of importance for acetabular component micromotion.

Energy-dispersive X-ray microanalysis of the bone mineral content in human trabecular bone: a comparison with ICPES and neutron activation analysis

To evaluate the accuracy of bone mineral composition determination by electron microprobe analysis (EDX) the measurements have been compared to instrumental neutron activation analysis (INAA) and chemical analysis (ICPES). Bone specimens from five femoral heads were used. The trabecular content of calcium (Ca) and phosphorus (P) was analyzed by the three different methods. The EDX method allows for a microstructural analysis of intact, methylmetacrylate-embedded, undecalcified bone and the measuring points can thus be distinctly identified centrally in each trabecula. The analysis yielded 25.8 +/- 0.7 wt % Ca and 10.5 +/- 0.1 wt % P, compared with 22.2 +/- 0.5 and 23.0 +/- 1.0 wt % Ca, and 9.83 +/- 0.21 and 10.02 +/- 0.44 wt % P for INAA and ICPES, respectively. The EDX analysis was calibrated by consecutive measurements of a hard, pressed tablet of hydroxyapatit of known content. The mean Ca content deviated with -0.38 wt % from the given content and P with -0.89 wt %. We could not verify any particular interference from the embedding procedure, however, it is possible that the relatively lower P content still may reflect this. The magnesium (Mg) concentration was 0.31 +/- 0.02 wt % by EDX and 0.26 +/- 0.02 wt % by INAA. The EDX analytical method provides a useful tool for simultaneous elemental quantification in bone. It has the advantage of permitting the use of regular bone biopsy material and thus allowing for a unique microstructural evaluation of the degree of mineralization.(ABSTRACT TRUNCATED AT 250 WORDS)

Periarticular bone in rheumatoid arthritis versus arthrosis. Histomorphometry in 103 hip biopsies

Histomorphologic differences of the periarticular bone in rheumatoid arthritis (RA) and osteoarthrosis (OA) may be of importance for long-term prosthetic fixation. We have evaluated bone specimens, obtained during total hip replacement from an acetabular and a femoral biopsy site, in 42 RA-hips and 61 OA-hips. In both groups the bone turnover was increased in the acetabulum compared to that in the femur. In the acetabulums the total trabecular bone volume was equal, but osteoid volume, osteoid surface, resorptive surface, and the appositional rate were increased in RA. On the femoral side, only the osteoid volume was higher in RA. The increased bone turnover with a greater amount of unmineralized tissue, as well as resorptive activity in the acetabulum, may be of importance for the higher rate of acetabular component migration and loosening after total hip replacement in RA.

Periarticular bone mineral content in rheumatoid arthritis and arthrosis of the hip. Dual photon X-ray absorptiometry in 53 cases

The bone mineral content (BMC) was determined by dual photon X-ray absorptiometry prior to hip replacement in 22 patients with rheumatoid arthritis and 31 with arthrosis. Compared with the arthrosis patients, the rheumatoids had approximately 20 percent lower bone mineral content in the proximal femur, the lumbar spine, and in the innominate bone superior to the acetabulum.

Circulating levels of vitamins K1 and K2 decreased in elderly women with hip fracture

We measured the serum levels of phylloquinone (vitamin K1) and of the menaquinones, MK-7 and MK-8, in a group of 51 women with a mean age of 81 years who were studied within a few hours after a hip fracture. A group of 38 healthy age-matched women randomly chosen from the same population served as controls. Patients with hip fracture had a marked reduction in serum vitamin K1 (336 +/- 302 versus 585 +/- 490 pg/ml, p < 0.01), MK-7 (120 +/- 84 versus 226 +/- 178 pg/ml, p < 0.001), and MK-8 (89 +/- 113 versus 161 +/- 145 pg/ml, p < 0.01), and a large number had undetectable levels, especially of MK-8. Vitamin K levels were not correlated with the time elapsed after fracture or with serum cortisol or other biochemical variables. These data suggest that patients with hip fracture have vitamin K deficiency, an abnormality that could affect bone metabolism through an impairment of the gamma carboxylation of the gla-containing proteins of bone.

Impairment of bone turnover in elderly women with hip fracture

Hip fracture is one of the most severe consequences of osteoporosis affecting aged women. However, abnormalities of bone turnover responsible for bone loss in this condition have not been clearly defined. To further evaluate the bone metabolic status of women sustaining hip fracture, we have prospectively measured serum osteocalcin as a marker of bone formation and urinary excretion of pyridinoline (Pyr) and deoxypyridinoline (D-pyr) cross-links as markers of bone collagen degradation in 174 independently living women (80 +/- 8 years) within a few hours after a hip fracture. Comparison was made with 77 age-matched controls (80 +/- 5 years) and 17 premenopausal women (39 +/- 3 years). In addition 15 of the patients were followed with daily measurements during the first postoperative week. At the time of admission osteocalcin was 20% lower in the fractured women compared to the elderly controls (7.6 +/- 3.8 vs. 9.5 +/- 4.5 ng/ml, P = 0.001). Pyr and D-pyr were 36% and 40% higher, respectively (P = 0.0001), than in elderly controls and 85% and 76% higher than in premenopausal controls (P = 0.0001). Serum osteocalcin did not correlate with the cortisol level measured at the same time (r = 0.03, ns), nor with serum albumin and creatinine. Serum osteocalcin remained unchanged within 18 hours after fracture, whereafter it progressively decreased until the third postoperative day. No correlation was noted between the excretion of pyridinoline cross-links and the time elapsed from fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum osteocalcin and fracture susceptibility in elderly women

The purpose of this investigation was to evaluate the bone turnover by using bone metabolic markers in relation to previous fracture history and independent of bone mass. Patients and controls were recruited from a population-based study of 193 women, all living in the same city and aged 60, 70, and 80 years. The bone mineral content (BMC) was measured bilaterally in the distal forearm by single-photon absorptiometry (SPA). At the same time, serum samples were obtained for biochemical analysis. Of the 193 women, we identified 26 with at least one major fracture during the past few years. Each of these 26 women with a certified recent previous fracture was individually matched with a woman from the same study group of equal BMC and age but without a fracture history. In the two groups, the serum samples were analyzed for osteocalcin, C-terminal procollagen peptide (P1CP), alkaline phosphatase, bone-specific alkaline phosphatase, calcium, phosphate, and albumin. The serum concentration of osteocalcin was 20% lower in the women with a previous fracture than in the controls (P = 0.03). The other markers of bone formation gave similar values in the two groups. There was a significant correlation between the osteocalcin and P1CP concentrations (P = 0.001). Our findings indicate that the susceptibility to fractures independent of factors such as age and BMC may be related to a decreased bone turnover.

Bone mineral normative data in Malmö, Sweden. Comparison with reference data and hip fracture incidence in other ethnic groups

The bone mineral mass was measured in 324 residents of the city of Malmö, Sweden, by dual energy roentgen absorptiometry (DEXA) using the Lunar DPX equipment--total body, hip, and lumbar vertebrae. The bone mineral content of the wrist was also measured with single photon absorptiometry (SPA) in 88 of the individuals. Weight, height, and vertebral height, as well as body fat, lean body mass, menarcheal age, menopausal age, and hand grip strength were determined. Measurements were compared with reference bone mineral content values from the United States, Japan, and France--also hip fracture incidence was compared. All bone mineral values decreased with age. A good correlation was found between the DEXA technique of total body bone mineral and the forearm SPA values. The bone mineral content was correlated with lean body mass and weight. The Malmö bone mineral content was on the same level as in the United States, but higher than in Japan and France. The comparatively high risk of fragility fractures in the Scandinavian countries compared with most other settings cannot be explained by low bone mass.

Earlier wrist fracture: a confounding factor in distal forearm bone screening

Thirty-six women aged 60, 70 or 80 years who had fractured one of their distal radii (Colles' fracture) 0 to 35 (median 10) years earlier were examined in this population-based study. Single photon measurements (SPA) were performed on both arms 1 cm and 6 cm proximal to the styloid process of the ulna. All women were questioned about earlier wrist fractures and which, if any, side had been affected. Information about the type and site of the fracture was also gathered from the hospital records. The bone mineral content (BMC) was found to be increased by almost 20% in the once-fractured radius at the distal measuring site (1 cm) when compared with the unaffected side. This difference did not seem to diminish with time. At the proximal measuring site there was no difference between the once-fractured and the non-fractured side. There was a progressive loss of bone mineral in the once-fractured arm during the first years after the fracture however. This appeared to be reversed after about 10 years to a relative gain, even though the correlation was weak. Six of the 36 women could not remember which side had been fractured and five could not remember having had such a fracture at all. Determination of osteoporosis by measuring forearm BMC with single photon densitometry is therefore of limited value in some women of the oldest age groups.