Clinical osteoarthritis of the hip and knee and fall risk: The role of low physical functioning and pain medication.

OBJECTIVE: Several studies have found an increased fall risk in persons with osteoarthritis (OA). However, most prospective studies did not use a clinical definition of OA. In addition, it is not clear which factors explain this risk. Our objectives were: (1) to confirm the prospective association between clinical OA of the hip and knee and falls; (2) to examine the modifying effect of sex; and (3) to examine whether low physical performance, low physical activity and use of pain medication are mediating these relationships. METHODS: Baseline and 1-year follow-up data from the European Project on OSteoArthritis (EPOSA) were used involving pre-harmonized data from five European population-based cohort studies (ages 65-85, n = 2535). Clinical OA was defined according to American College of Rheumatology (ACR) criteria. Falls were assessed using self-report. RESULTS: Over the follow-up period, 27.7% of the participants fell once or more (defined as faller), and 9.8% fell twice or more (recurrent faller). After adjustment for confounding, clinical knee OA was associated with the risk of becoming a recurrent faller (relative risk=1.55; 95% confidence interval: 1.10-2.18), but not with the risk of becoming a faller. No associations between clinical hip OA and (recurrent) falls were observed after adjustment for confounding. Use of opioids and analgesics mediated the associations between clinical OA and (recurrent) falls, while physical performance and physical activity did not. CONCLUSION: Individuals with clinical knee OA were at increased risk for recurrent falls. This relationship was mediated by pain medication, particularly opioids. The fall risk needs to be considered when discussing the risk benefit ratio of prescribing these medications.

Longitudinal Change in Peripheral Quantitative Computed Tomography Assessment in Older Adults: The Hertfordshire Cohort Study.

There are few longitudinal data on change in bone structure and muscle mass, strength and function in later life. We report these, and consider bone-muscle interrelationships in older men and women. We studied 188 men and 166 women from the Hertfordshire Cohort Study, who underwent peripheral quantitative computed tomography (pQCT) of the radius and tibia in 2004-2005 and then again in 2011-2012. Grip strength and gait speed were also assessed at both timepoints. Percentage change per year was calculated for grip strength, gait speed, muscle cross-sectional area (mCSA), fat cross-sectional area (fCSA) and diaphyseal bone parameters [total area (Tt.Ar), cortical area (Ct.Ar), cortical density (cBMD) and trabecular density (tBMD)]. The mean (SD) age of men and women at baseline was 68.9 (2.5) and 69.2 (2.6) years, respectively. Rates of muscle area and strength loss did not differ by sex. Tt.Ar increased with age and faster in men [mean (SD) 1.78 (1.64) %/year] than women [mean (SD) 1.03 (1.69) %/year] in the radius (p < 0.001). In both the radius (p = 0.006) and tibia (p < 0.001), Ct.Ar reduced more rapidly in women than men. Change in Ct.Ar was associated with change in muscle area in the corresponding limb (radius; men: regression coefficient 0.36, 95% CI 0.20-0.52, p < 0.001; tibia; men: regression coefficient 0.14, 95% CI 0.00-0.27, p = 0.043, women: regression coefficient 0.16, 95% CI 0.01-0.30, p = 0.032). We have demonstrated that muscle strength and function decrease faster than muscle mass and have provided further evidence that changes in bone structure with age differ by sex.

Diet Quality and Bone Measurements Using HRpQCT and pQCT in Older Community-Dwelling Adults from the Hertfordshire Cohort Study.

There are few data describing associations between dietary patterns and bone microarchitecture. This study investigated the relationship between diet quality and HRpQCT and pQCT measures in older adults. Data were available for 184 men and 166 women. Dietary data were collected at baseline (1998-2003) using an administered food frequency questionnaire. A 'prudent' diet score (PDS) was identified using principal component analysis and used as an indicator of dietary quality. HRpQCT and pQCT images were acquired at follow-up in 2012, from the non-dominant distal radius and tibia using Scanco XtremeCT and Stratec XCT2000 instrument scanners, respectively. The mean (SD) PDS was - 0.24 (1.23) for men and 0.62 (1.14) for women. In women, a significant positive relationship was found between baseline dietary pattern and total and trabecular area at both the radius and the tibia, measured by HRpQCT. Similar trends were observed with pQCT parameters. Positive associations were observed for tibia total area (38% slice). At the radius, significant positive associations were found for total area (4% slice) and polar strength strain index (33% slice). All relationships remained robust to adjustment. For men, although patterns were similar, there were no significant associations for HRpQCT outcomes. Significant associations were observed for baseline PDS and polar strength strain and total area (66% slice) at the radius, measured by pQCT. Our data suggest that diets high in fruit, vegetables, oily fish and whole grain cereals in early old age are associated with greater bone size but not volumetric bone density or microarchitecture in later life in women.

Mild cognitive impairment is associated with poor physical function but not bone structure or density in late adulthood: findings from the Hertfordshire cohort study.

This study investigated the association between mild cognitive impairment (MCI) and physical function and bone health in older adults. MCI was associated with poor physical performance but not bone mineral density or bone microarchitecture. PURPOSE: Cross-sectional study to investigate the association between mild cognitive impairment (MCI) and physical performance, and bone health, in a community-dwelling cohort of older adults. METHODS: Cognitive function of 222 men and 221 women (mean age 75.5 and 75.8 years in men and women, respectively) was assessed by the Strawbridge questionnaire and Mini Mental State Exam (MMSE). Participants underwent dual-energy X-ray absorptiometry (DXA), peripheral-quantitative computed tomography (pQCT) and high-resolution peripheral-quantitative computed tomography (HR-pQCT) scans to assess their bone density, strength and microarchitecture. Their physical function was assessed and a physical performance (PP) score was recorded. RESULTS: In the study, 11.8% of women and 8.1% of men were cognitively impaired on the MMSE (score < 24). On the Strawbridge questionnaire, 24% of women were deemed cognitively impaired compared to 22.3% of men. Cognitive impairment on the Strawbridge questionnaire was associated with poorer physical performance score in men but not in women in the unadjusted analysis. MMSE < 24 was strongly associated with the risk of low physical performance in men (OR 12.9, 95% CI 1.67, 99.8, p = 0.01). Higher MMSE score was associated with better physical performance in both sexes. Poorer cognitive function, whether assessed by the Strawbridge questionnaire, or by MMSE score, was not associated with bone density, shape or microarchitecture, in either sex. CONCLUSION: MCI in older adults was associated with poor physical performance, but not bone density, shape or microarchitecture.

The relationship of bone properties using high resolution peripheral quantitative computed tomography to radiographic components of hip osteoarthritis.

OBJECTIVE: Positive associations between radiographic osteoarthritis (OA) and areal bone mineral density (BMD) have been demonstrated and appear strongest when bony features of OA are considered. To date, these associations have not been assessed using HRpQCT. DESIGN: A total of 318 participants (170 men and 148 women), aged 72.1-81.4 years from a non-selected cohort, underwent HRpQCT of the distal radius and tibia along with hip radiography. Differences in bone microarchitecture were assessed between those with and without osteophytes, sclerosis or joint space narrowing (JSN) in either hip. RESULTS: Men with osteophytes alone had significantly higher radial trabecular volumetric BMD (Tb.vBMD) and radial and tibial trabecular thickness (Tb.Th). Men with both sclerosis and osteophytes had significantly higher cortical volumetric BMD (Ct.vBMD) and cortical thickness (Ct.Th) at the distal tibia than those with osteophytes alone (P < 0.05). These relationships were maintained after adjustment for age and Body Mass Index (BMI), and were not replicated in women. Bone microarchitecture did not differ significantly in those with JSN from those without it in men or women. CONCLUSIONS: Our findings suggest higher Tb.vBMD and Tb.Th in men with osteophytosis but higher tibial Ct.vBMD and Ct.Th in men with hip joint sclerosis. These results do however require replication in other cohorts.

A novel accelerometer-based method to describe day-to-day exposure to potentially osteogenic vertical impacts in older adults: findings from a multi-cohort study.

This observational study assessed vertical impacts experienced in older adults as part of their day-to-day physical activity using accelerometry and questionnaire data. Population-based older adults experienced very limited high-impact activity. The accelerometry method utilised appeared to be valid based on comparisons between different cohorts and with self-reported activity. INTRODUCTION: We aimed to validate a novel method for evaluating day-to-day higher impact weight-bearing physical activity (PA) in older adults, thought to be important in protecting against osteoporosis, by comparing results between four cohorts varying in age and activity levels, and with self-reported PA levels. METHODS: Participants were from three population-based cohorts, MRC National Survey of Health and Development (NSHD), Hertfordshire Cohort Study (HCS) and Cohort for Skeletal Health in Bristol and Avon (COSHIBA), and the Master Athlete Cohort (MAC). Y-axis peaks (reflecting the vertical when an individual is upright) from a triaxial accelerometer (sampling frequency 50 Hz, range 0-16 g) worn at the waist for 7 days were classified as low (0.5-1.0 g), medium (1.0-1.5 g) or higher (≥1.5 g) impacts. RESULTS: There were a median of 90, 41 and 39 higher impacts/week in NSHD (age 69.5), COSHIBA (age 76.8) and HCS (age 78.5) participants, respectively (total n = 1512). In contrast, MAC participants (age 68.5) had a median of 14,322 higher impacts/week. In the three population cohorts combined, based on comparison of beta coefficients, moderate-high-impact activities as assessed by PA questionnaire were suggestive of stronger association with higher impacts from accelerometers (0.25 [0.17, 0.34]), compared with medium (0.18 [0.09, 0.27]) and low impacts (0.13 [0.07,0.19]) (beta coefficient, with 95 % CI). Likewise in MAC, reported moderate-high-impact activities showed a stronger association with higher impacts (0.26 [0.14, 0.37]), compared with medium (0.14 [0.05, 0.22]) and low impacts (0.03 [-0.02, 0.08]). CONCLUSIONS: Our new accelerometer method appears to provide valid measures of higher vertical impacts in older adults. Results obtained from the three population-based cohorts indicate that older adults generally experience very limited higher impact weight-bearing PA.

Lower leg arterial calcification assessed by high-resolution peripheral quantitative computed tomography is associated with bone microstructure abnormalities in women.

In older women, the presence of lower leg arterial calcification assessed by high-resolution peripheral quantitative computed tomography is associated with relevant bone microstructure abnormalities at the distal tibia and distal radius. INTRODUCTION: Here, we report the relationships of bone geometry, volumetric bone mineral density (BMD) and bone microarchitecture with lower leg arterial calcification (LLAC) as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT). METHODS: We utilized the Hertfordshire Cohort Study (HCS), where we were able to study associations between measures obtained from HR-pQCT of the distal radius and distal tibia in 341 participants with or without LLAC. Statistical analyses were performed separately for women and men. We used linear regression models to investigate the cross-sectional relationships between LLAC and bone parameters. RESULTS: The mean (SD) age of participants was 76.4 (2.6) and 76.1 (2.5) years in women and men, respectively. One hundred and eleven of 341 participants (32.6 %) had LLAC that were visible and quantifiable by HR-pQCT. The prevalence of LLAC was higher in men than in women (46.4 % (n = 83) vs. 17.3 % (n = 28), p < 0.001). After adjustment for confounding factors, we found that women with LLAC had substantially lower Ct.area (ß = -0.33, p = 0.016), lower Tb.N (ß = -0.54, p = 0.013) and higher Tb.Sp (ß = 0.54, p = 0.012) at the distal tibia and lower Tb.Th (ß = -0.49, p = 0.027) at the distal radius compared with participants without LLAC. Distal radial or tibial bone parameter analyses in men according to their LLAC status revealed no significant differences with the exception of Tb.N (ß = 0.27, p = 0.035) at the distal tibia. CONCLUSION: In the HCS, the presence of LLAC assessed by HR-pQCT was associated with relevant bone microstructure abnormalities in women. These findings need to be replicated and further research should study possible pathophysiological links between vascular calcification and osteoporosis.

Cluster analysis of bone microarchitecture from high resolution peripheral quantitative computed tomography demonstrates two separate phenotypes associated with high fracture risk in men and women.

Osteoporosis is a major healthcare problem which is conventionally assessed by dual energy X-ray absorptiometry (DXA). New technologies such as high resolution peripheral quantitative computed tomography (HRpQCT) also predict fracture risk. HRpQCT measures a number of bone characteristics that may inform specific patterns of bone deficits. We used cluster analysis to define different bone phenotypes and their relationships to fracture prevalence and areal bone mineral density (BMD). 177 men and 159 women, in whom fracture history was determined by self-report and vertebral fracture assessment, underwent HRpQCT of the distal radius and femoral neck DXA. Five clusters were derived with two clusters associated with elevated fracture risk. "Cluster 1" contained 26 women (50.0% fractured) and 30 men (50.0% fractured) with a lower mean cortical thickness and cortical volumetric BMD, and in men only, a mean total and trabecular area more than the sex-specific cohort mean. "Cluster 2" contained 20 women (50.0% fractured) and 14 men (35.7% fractured) with a lower mean trabecular density and trabecular number than the sex-specific cohort mean. Logistic regression showed fracture rates in these clusters to be significantly higher than the lowest fracture risk cluster [5] (p<0.05). Mean femoral neck areal BMD was significantly lower than cluster 5 in women in cluster 1 and 2 (p<0.001 for both), and in men, in cluster 2 (p<0.001) but not 1 (p=0.220). In conclusion, this study demonstrates two distinct high risk clusters in both men and women which may differ in etiology and response to treatment. As cluster 1 in men does not have low areal BMD, these men may not be identified as high risk by conventional DXA alone.

Non-invasive Assessment of Lower Limb Geometry and Strength Using Hip Structural Analysis and Peripheral Quantitative Computed Tomography: A Population-Based Comparison.

Hip fracture is the most significant complication of osteoporosis in terms of mortality, long-term disability and decreased quality of life. In the recent years, different techniques have been developed to assess lower limb strength and ultimately fracture risk. Here we examine relationships between two measures of lower limb bone geometry and strength; proximal femoral geometry and tibial peripheral quantitative computed tomography. We studied a sample of 431 women and 488 men aged in the range 59-71 years. The hip structural analysis (HSA) programme was employed to measure the structural geometry of the left hip for each DXA scan obtained using a Hologic QDR 4500 instrument while pQCT measurements of the tibia were obtained using a Stratec 2000 instrument in the same population. We observed strong sex differences in proximal femoral geometry at the narrow neck, intertrochanteric and femoral shaft regions. There were significant (p < 0.001) associations between pQCT-derived measures of bone geometry (tibial width; endocortical diameter and cortical thickness) and bone strength (strength strain index) with each corresponding HSA variable (all p < 0.001) in both men and women. These results demonstrate strong correlations between two different methods of assessment of lower limb bone strength: HSA and pQCT. Validation in prospective cohorts to study associations of each with incident fracture is now indicated.

Availability and use of neighborhood resources by older people with osteoarthritis: Results from the European Project on OSteoArthritis.

This study examines the availability and use of neighborhood resources in relation to clinical lower limb osteoarthritis (LLOA) in older participants from six European countries. Of the 2757 participants (65-85 years), 22.7% had LLOA. Participants with LLOA made more use of places to sit (OR=2.50; CI: 1.36-4.60 in the UK), and less use of parks and walking areas (OR=0.30; CI: 0.12-0.75 in Sweden), compared to participants without LLOA, particularly in countries with high availability of resources. The results suggest that specific features of the environment impact the use of neighborhood resources by older adults with LLOA.

Impact of clinical osteoarthritis of the hip, knee and hand on self-rated health in six European countries: the European Project on OSteoArthritis.

PURPOSE: Osteoarthritis (OA) has been shown to be associated with decreased physical function, which may impact upon a person's self-rated health (SRH). Only a few studies have examined the association between OA and SRH in the general population, but to date none have used a clinical definition of OA. The objectives are: (1) To examine the cross-sectional association between clinical OA and fair-to-poor SRH in the general population; (2) To examine whether this association differs between countries; (3) To examine whether physical function is a mediator in the association between clinical OA and SRH. METHODS: Baseline data of the European Project on OSteoArthritis (EPOSA) were used, which includes pre-harmonized data from six European cohort studies (n = 2709). Clinical OA was defined according to the American College of Rheumatology criteria. SRH was assessed using one question: How is your health in general? Physical function was assessed using the Western Ontario and McMaster Universities OA Index and Australian/Canadian OA Hand Index. RESULTS: The prevalence of fair-to-poor SRH ranged from 19.8 % in the United Kingdom to 63.5 % in Italy. Although country differences in the strength of the associations were observed, clinical OA of the hip, knee and hand were significantly associated with fair-to-poor SRH in five out of six European countries. In most countries and at most sites, the association between clinical OA and fair-to-poor SRH was partly or fully mediated by physical function. CONCLUSIONS: Clinical OA at different sites was related to fair-to-poor SRH in the general population. Most associations were (partly) mediated by physical functioning, indicating that deteriorating physical function in patients with OA should be a point of attention in patient care.

Definitions of Sarcopenia: Associations with Previous Falls and Fracture in a Population Sample.

Sarcopenia is common in later life and may be associated with adverse health outcomes such as disability, falls and fracture. There is no consensus definition for its diagnosis although diagnostic algorithms have been proposed by the European Working Group for Sarcopenia in Older People (EWGSOP), the International Working Group on Sarcopenia (IWGS) and the Foundation for the National Institutes of Health Sarcopenia Project (FNIH). More recently, Binkley and colleagues devised a score-based system for the diagnosis of "dysmobility syndrome" in an attempt to combine adverse musculoskeletal phenotypes, including sarcopenia and osteoporosis, in order to identify older individuals at particular risk. We applied these criteria to participants from the Hertfordshire Cohort Study to define their prevalence in an unselected cohort of UK community-dwelling older adults and assess their relationships with previous falls and fracture. Body composition and areal bone mineral density were measured using dual-energy X-ray absorptiometry, gait speed was determined by a 3-m walk test and grip strength was assessed with a Jamar hand-held dynamometer. Researcher-administered questionnaires were completed detailing falls and fracture history. The prevalence of sarcopenia in this cohort was 3.3, 8.3 and 2.0% using the EWGSOP, IWGS and related definition of FNIH, respectively; 24.8% of individuals had dysmobility syndrome. Individuals with dysmobility reported significantly higher number of falls (last year and since the age of 45 years) (p < 0.01) than those without it, but no increased fracture rate was observed in this group (p = 0.96). Those with sarcopenia as defined by the IWGS reported significantly higher falls in the last year and prevalent fractures (falls in the last year: OR 2.51; CI 1.09-5.81; p = 0.03; fractures OR 2.50; CI 1.05-5.92; p = 0.04) but these significant associations were not seen when the EWGSOP definition was applied. The IWGS definition of sarcopenia appears to be an effective means of identifying individuals at risk of prevalent adverse musculoskeletal events.

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

UNLABELLED: 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.

Osteoporosis and sarcopenia in older age.

Osteoporosis and sarcopenia are common in older age and associated with significant morbidity and mortality. Consequently, they are both attended by a considerable socioeconomic burden. Osteoporosis was defined by the World Health Organisation (WHO) in 1994 as a bone mineral density of less than 2.5 standard deviations below the sex-specific young adult mean and this characterisation has been adopted globally. Subsequently, a further step forward was taken when bone mineral density was incorporated into fracture risk prediction algorithms, such as the Fracture Risk Assessment Tool (FRAX®) also developed by the WHO. In contrast, for sarcopenia there have been several diagnostic criteria suggested, initially relating to low muscle mass alone and more recently low muscle mass and muscle function. However, none of these have been universally accepted. This has led to difficulties in accurately delineating the burden of disease, exploring geographic differences, and recruiting appropriate subjects to clinical trials. There is also uncertainty about how improvement in sarcopenia should be measured in pharmaceutical trials. Reasons for these difficulties include the number of facets of muscle health available, e.g. mass, strength, function, and performance, and the various clinical outcomes to which sarcopenia can be related such as falls, fracture, disability and premature mortality. It is imperative that a universal definition of sarcopenia is reached soon to facilitate greater progress in research into this debilitating condition. This article is part of a Special Issue entitled "Muscle Bone Interactions".

Ischemic heart disease is associated with lower cortical volumetric bone mineral density of distal radius.

UNLABELLED: In this study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was used to investigate geometric, volumetric and microstructural parameters at the distal radius and at the distal tibia in participants with ischaemic heart disease. We found that, compared with participants without ischaemic heart disease, they had substantially lower cortical volumetric bone mineral density (BMD) at the distal radius. INTRODUCTION: HR-pQCT captures novel aspects of bone geometry and volumetric bone mineral density (vBMD) and offers the ability to measure bone microarchitecture, but data relating measures obtained from this technique in patients with ischemic heart disease (IHD) are lacking. METHODS: Here, we report an analysis from the Hertfordshire Cohort Study, where we were able to study associations between measures obtained from HR-pQCT of distal radius and distal tibia in 350 participants (184 men and 166 women) aged 71.5-80.5 years with or without IHD (e.g. heart attack, angina or heart failure; n = 75 and n = 275, respectively). RESULTS: Analyses for all participants (men and women together) revealed that cortical vBMD (Ct.vBMD) was lower (p < 0.001) and cortical thickness (Ct.th) was not different (p = 0.519), whereas cortical porosity (Ct.Po) was higher (p = 0.016) in participants with IHD at the distal radius. Moreover, trabecular microarchitectural parameters were not significantly different in patients with IHD (p > 0.05 for all). Adjustment for a priori confounders (age, gender, body mass index, smoking status, alcohol consumption, high blood pressure and diabetes mellitus) did not materially affect the relationship described for Ct.vBMD (p = 0.002), but differences in Ct.Po were attenuated. Analyses in men alone revealed that only Ct.vBMD was lower at the distal radius in participants with IHD with and without adjustment for a priori confounders (p = 0.0002 and p = 0.004, respectively), whereas no statistical differences were found in women, although patterns of differences were similar in both sexes. Moreover, no association was found between IHD and bone parameters at the distal tibia either in men or women. CONCLUSIONS: We have demonstrated that IHD is associated with lower Ct.vBMD of the distal radius.

Diabetes is a risk factor for knee osteoarthritis progression.

PURPOSE: Recent studies have suggested that metabolic factors (obesity, diabetes, hypertension and dyslipidemia) and their clustering in metabolic syndrome (MetS) might be involved in the pathophysiology of knee osteoarthritis (OA). We investigated their impact on radiographic progression by an annualised measure of the joint space narrowing (JSN) of the medial tibiofemoral compartment. METHODS: 559 patients older than 50 years with symptomatic knee OA were recruited for the placebo arm of the SEKOIA trial. The presence of diabetes, hypertension and dyslipidemia was determined at baseline interview. Body mass index (BMI) was calculated, obesity was considered >30 kg/m(2). MetS was defined by the sum of metabolic factors ≥ 3. Minimal medial tibiofemoral joint space on plain radiographs was measured by an automated method at baseline and then annually for up to 3 years. RESULTS: The mean age of patients was 62.8 [62.2-63.4] years; 392 were women. A total of 43.8% was obese, 6.6% had type 2 diabetes, 45.1% hypertension, 27.6% dyslipidemia and 13.6% MetS. Mean annualised JSN was greater for patients with type 2 diabetes than without diabetes (0.26 [-0.35 to -0.17] vs 0.14 [-0.16 to -0.12] mm; P = 0.001). This association remained significant after adjustment for sex, age, BMI, hypertension and dyslipidemia (P = 0.018). In subgroup analysis, type 2 diabetes was a significant predictor of JSN in males but not females. The other metabolic factors and MetS were not associated with annualised JSN. CONCLUSION: Type 2 diabetes was a predictor of joint space reduction in men with established knee OA. No relationships were found between MetS or other metabolic factors and radiographic progression.

Individuals with high bone mass have an increased prevalence of radiographic knee osteoarthritis.

We previously reported an association between high bone mass (HBM) and a bone-forming phenotype of radiographic hip osteoarthritis (OA). As knee and hip OA have distinct risk factors, in this study we aimed to determine (i) whether HBM is also associated with knee OA, and (ii) whether the HBM knee OA phenotype demonstrates a similar pattern of radiographic features to that observed at the hip. HBM cases (defined by DXA BMD Z-scores) from the UK-based HBM study were compared with unaffected family controls and general population controls from the Chingford and Hertfordshire cohort studies. A single blinded observer graded AP weight-bearing knee radiographs for features of OA (Kellgren-Lawrence score, osteophytes, joint space narrowing (JSN), sclerosis) using an atlas. Analyses used logistic regression, adjusting a priori for age and gender, and additionally for BMI as a potential mediator of the HBM-OA association, using Stata v12. 609 HBM knees in 311 cases (mean age 60.8years, 74% female) and 1937 control knees in 991 controls (63.4years, 81% female) were analysed. The prevalence of radiographic knee OA, defined as Kellgren-Lawrence grade≥2, was increased in cases (31.5% vs. 20.9%), with age and gender adjusted OR [95% CI] 2.38 [1.81, 3.14], p<0.001. The association between HBM and osteophytosis was stronger than that for JSN, both before and after adjustment for BMI which attenuated the ORs for knee OA and osteophytes in cases vs. controls by approximately 50%. Our findings support a positive association between HBM and knee OA. This association was strongest for osteophytes, suggesting HBM confers a general predisposition to a subtype of OA characterised by increased bone formation.

Further evidence of the developmental origins of osteoarthritis: results from the Hertfordshire Cohort Study.

Investigators have suggested a link between birth weight and both hand and lumbar spine osteoarthritis (OA). In this study, we sought to extend these observations by investigating relationships between growth in early life, and clinical and radiological diagnoses of OA at the hand, knee and hip, among participants from the Hertfordshire Cohort Study. Data were available for 222 men and 222 women. Clinical OA was defined based on American College of Rheumatology criteria. Radiographs were taken of the knees and hips, and graded for the presence of osteophytes and overall Kellgren and Lawrence (KL) score. Lower weight at year one was associated with higher rates of clinical hand OA (OR 1.396, 95% CI 1.05, 1.85, P=0.021). Individuals with lower birth weights were more likely to have hip osteophytes (OR 1.512, 95% CI 1.14, 2.00, P=0.004) and this remained robust after adjustment for confounders. Furthermore, a low weight at one year was also associated with a higher osteophyte number in the lateral compartment of the knee, after adjustment for confounders (OR 1.388, 95% CI 1.01, 1.91, P=0.043). We have found further evidence of a relationship between early life factors and adult OA. These findings accord with previous studies.

Prevalence of radiographic hip osteoarthritis is increased in high bone mass.

OBJECTIVE: Epidemiological studies have shown an association between increased bone mineral density (BMD) and osteoarthritis (OA), but whether this represents cause or effect remains unclear. In this study, we used a novel approach to investigate this question, determining whether individuals with High Bone Mass (HBM) have a higher prevalence of radiographic hip OA compared with controls. DESIGN: HBM cases came from the UK-based HBM study: HBM was defined by BMD Z-score. Unaffected relatives of index cases were recruited as family controls. Age-stratified random sampling was used to select further population controls from the Chingford and Hertfordshire cohort studies. Pelvic radiographs were pooled and assessed by a single observer blinded to case-control status. Analyses used logistic regression, adjusted for age, gender and body mass index (BMI). RESULTS: 530 HBM hips in 272 cases (mean age 62.9 years, 74% female) and 1702 control hips in 863 controls (mean age 64.8 years, 84% female) were analysed. The prevalence of radiographic OA, defined as Croft score ≥3, was higher in cases compared with controls (20.0% vs 13.6%), with adjusted odds ratio (OR) [95% CI] 1.52 [1.09, 2.11], P = 0.013. Osteophytes (OR 2.12 [1.61, 2.79], P < 0.001) and subchondral sclerosis (OR 2.78 [1.49, 5.18], P = 0.001) were more prevalent in cases. However, no difference in the prevalence of joint space narrowing (JSN) was seen (OR 0.97 [0.72, 1.33], P = 0.869). CONCLUSIONS: An increased prevalence of radiographic hip OA and osteophytosis was observed in HBM cases compared with controls, in keeping with a positive association between HBM and OA and suggesting that OA in HBM has a hypertrophic phenotype.