Statistical shape modelling provides a responsive measure of morphological change in knee osteoarthritis over 12 months.

OBJECTIVES: Responsive biomarkers are needed to assess the progression of OA and their lack has hampered previous clinical trials. Statistical shape modelling (SSM) from radiographic images identifies those at greatest risk of fast-progression or joint replacement, but its sensitivity to change has not previously been measured. This study evaluates the responsiveness of SSM in knee OA in a 12-month observational study. METHODS: A total of 109 people were recruited who had undergone knee radiographs in the previous 12 months, and were grouped based on severity of radiographic OA (Kellgren-Lawrence grading). An SSM was built from three dual-energy X-ray absorptiometry scans at 6-month intervals. Change-over-time and OA were assessed using generalized estimating equations, standardized response means (SRM) and reliable change indices. RESULTS: Mode 1 showed typical features of radiographic OA and had a strong link with Kellgren-Lawrence grading but did not change significantly during the study. Mode 3 showed asymmetrical changes consistent with medial cartilage loss, osteophytes and joint malalignment, and was responsive to change, with a 12-month SRM of 0.63. The greatest change was observed in the moderate radiographic OA group (SRM 0.92) compared with the controls (SRM 0.21), and the reliable change index identified 14% of this group whose progression was clinically significant. CONCLUSION: Shape changes linked the progression of osteophytosis with increasing malalignment within the joint. Modelling of the whole joint enabled quantification of change beyond the point where bone-to-bone contact has been made. The knee SSM is, therefore, a responsive biomarker for radiographic change in knees over 12 months.

Application of the Systematic Molecular Fragmentation by Annihilation Method to ab Initio NMR Chemical Shift Calculations.

NMR is a powerful tool for obtaining information on the structural characterization and dynamics of proteins, and nucleic acids, and their complexes. The complexity of the spectra is such that elucidation through computational simulation is a much desired thing. However, the size of most structures of interest is such that they remain out of reach of accurate quantum chemical techniques. Fragmentation methods have been shown to be a viable means of reducing the cost of ab initio calculations to enable the prediction of molecular properties of large systems to chemical accuracy. We look at the systematic molecular fragmentation by annihilation method for a model peptide system and show that this procedure reproduces the shielding constants of a full calculation at only a fraction of the cost. Discussion of the considerations needed in applying this method is discussed and comparison made with the results of the similar fragment molecular orbital and ONIOM methods.

Randomized trial of switching from prescribed non-selective non-steroidal anti-inflammatory drugs to prescribed celecoxib: the Standard care vs. Celecoxib Outcome Trial (SCOT).

BACKGROUND: Selective cyclooxygenase-2 inhibitors and conventional non-selective non-steroidal anti-inflammatory drugs (nsNSAIDs) have been associated with adverse cardiovascular (CV) effects. We compared the CV safety of switching to celecoxib vs. continuing nsNSAID therapy in a European setting. METHOD: Patients aged 60 years and over with osteoarthritis or rheumatoid arthritis, free from established CV disease and taking chronic prescribed nsNSAIDs, were randomized to switch to celecoxib or to continue their previous nsNSAID. The primary endpoint was hospitalization for non-fatal myocardial infarction or other biomarker positive acute coronary syndrome, non-fatal stroke or CV death analysed using a Cox model with a pre-specified non-inferiority limit of 1.4 for the hazard ratio (HR). RESULTS: In total, 7297 participants were randomized. During a median 3-year follow-up, fewer subjects than expected developed an on-treatment (OT) primary CV event and the rate was similar for celecoxib, 0.95 per 100 patient-years, and nsNSAIDs, 0.86 per 100 patient-years (HR = 1.12, 95% confidence interval, 0.81-1.55; P = 0.50). Comparable intention-to-treat (ITT) rates were 1.14 per 100 patient-years with celecoxib and 1.10 per 100 patient-years with nsNSAIDs (HR = 1.04; 95% confidence interval, 0.81-1.33; P = 0.75). Pre-specified non-inferiority was achieved in the ITT analysis. The upper bound of the 95% confidence limit for the absolute increase in OT risk associated with celecoxib treatment was two primary events per 1000 patient-years exposure. There were only 15 adjudicated secondary upper gastrointestinal complication endpoints (0.078/100 patient-years on celecoxib vs. 0.053 on nsNSAIDs OT, 0.078 vs. 0.053 ITT). More gastrointestinal serious adverse reactions and haematological adverse reactions were reported on nsNSAIDs than celecoxib, but more patients withdrew from celecoxib than nsNSAIDs (50.9% patients vs. 30.2%; P < 0.0001). INTERPRETATION: In subjects 60 years and over, free from CV disease and taking prescribed chronic nsNSAIDs, CV events were infrequent and similar on celecoxib and nsNSAIDs. There was no advantage of a strategy of switching prescribed nsNSAIDs to prescribed celecoxib. This study excluded an increased risk of the primary endpoint of more than two events per 1000 patient-years associated with switching to prescribed celecoxib. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/show/NCT00447759; Unique identifier: NCT00447759.

Degenerative inter-vertebral disc disease osteochondrosis intervertebralis in Europe: prevalence, geographic variation and radiological correlates in men and women aged 50 and over.

Objectives: To assess the prevalences across Europe of radiological indices of degenerative inter-vertebral disc disease (DDD); and to quantify their associations with, age, sex, physical anthropometry, areal BMD (aBMD) and change in aBMD with time. Methods: In the population-based European Prospective Osteoporosis Study, 27 age-stratified samples of men and women from across the continent aged 50+ years had standardized lateral radiographs of the lumbar and thoracic spine to evaluate the severity of DDD, using the Kellgren-Lawrence (KL) scale. Measurements of anterior, mid-body and posterior vertebral heights on all assessed vertebrae from T4 to L4 were used to generate indices of end-plate curvature. Results: Images from 10 132 participants (56% female, mean age 63.9 years) passed quality checks. Overall, 47% of men and women had DDD grade 3 or more in the lumbar spine and 36% in both thoracic and lumbar spine. Risk ratios for DDD grades 3 and 4, adjusted for age and anthropometric determinants, varied across a three-fold range between centres, yet prevalences were highly correlated in men and women. DDD was associated with flattened, non-ovoid inter-vertebral disc spaces. KL grade 4 and loss of inter-vertebral disc space were associated with higher spine aBMD. Conclusion: KL grades 3 and 4 are often used clinically to categorize radiological DDD. Highly variable European prevalences of radiologically defined DDD grades 3+ along with the large effects of age may have growing and geographically unequal health and economic impacts as the population ages. These data encourage further studies of potential genetic and environmental causes.

The Scottish Early Rheumatoid Arthritis (SERA) Study: an inception cohort and biobank.

BACKGROUND: The Scottish Early Rheumatoid Arthritis (SERA) study is an inception cohort of rheumatoid (RA) and undifferentiated arthritis (UA) patients that aims to provide a contemporary description of phenotype and outcome and facilitate discovery of phenotypic and prognostic biomarkers METHODS: Demographic and clinical outcome data are collected from newly diagnosed RA/UA patients every 6 months from around Scotland. Health service utilization data is acquired from Information Services Division, NHS National Services Scotland. Plain radiographs of hands and feet are collected at baseline and 12 months. Additional samples of whole blood, plasma, serum and filtered urine are collected at baseline, 6 and 12 months RESULTS: Results are available for 1073 patients; at baseline, 76 % were classified as RA and 24 % as UA. Median time from onset to first review was 163 days (IQR97-323). Methotrexate was first-line DMARD for 75 % patients. Disease activity, functional ability and health-related quality of life improved significantly between baseline and 24 months, however the proportion in any employment fell (51 to 38 %, p = 0.0005). 24 % patients reported symptoms of anxiety and/or depression at baseline. 35/391 (9 %) patients exhibited rapid radiographic progression after 12 months. The SERA Biobank has accrued 60,612 samples CONCLUSIONS: In routine care, newly diagnosed RA/UA patients experience significant improvements in disease activity, functional ability and health-related quality of life but have high rates of psychiatric symptoms and declining employment rates. The co-existence of a multi-domain description of phenotype and a comprehensive biobank will facilitate multi-platform translational research to identify predictive markers of phenotype and prognosis.

Normocalcaemic hypoparathyroidism: prevalence and effect on bone status in older women. The OPUS study.

OBJECTIVE: There are no consistent data on the prevalence and bone status of normocalcaemic hypoparathyroidism (NHYPO) as defined by normal adjusted calcium and low PTH level. Our aim was to determine the prevalence and the metabolic bone profile of NHYPO in older women, assessing its evolution over time. The second objective was to evaluate the prevalence of other calcium metabolic disorders. DESIGN: The Osteoporosis and Ultrasound Study (OPUS) is a 6-yr prospective study of fracture-related factors. PARTICIPANTS: A total of 2419 older women (age 55-79 yrs) and 258 younger women (age 30-40 yrs) participated. Complete follow-up data were available in 1416 subjects. MEASUREMENTS: After calculating the adjusted calcium according to James' formula, we identified 'abnormal' calcium and PTH using Mahalanobis distances and allocated older women into different pathological categories using reference intervals from the healthy young women. RESULTS: We identified 57 subjects with NHYPO (2·4%). These women had lower than expected bone turnover as assessed by bone alkaline phosphatase (-14·5%, 95% CI: -26·2 to -3·0, P = 0·007), CTX (-66·3%, 95% CI: -74·0 to -56·4, P < 0·001) and osteocalcin (-36·8%, 95% CI: -45·6 to -26·6, P < 0·001). After 6 years, of the 35 NHYPO subjects with follow-up data, none developed overt hypoparathyroidism and only 15 (0·6%) subjects had persistent evidence of NHYPO. We also identified 86 subjects (3·6%) affected by hyperparathyroid hypercalcaemia. CONCLUSION: This is the first large population-based study to investigate NHYPO in older women. NHYPO is fairly common, not always persistent and is characterized by low bone turnover.

Calculating nuclear magnetic resonance shieldings using systematic molecular fragmentation by annihilation.

SMFA was used to calculate NMR shieldings in a test set of 15 molecules. Level 4 fragments were found to yield satisfactory results when hydrogen bonding was included in the calculations. The utility of additional long range corrections was also investigated. It was found that with hydrogen bonding already included, ab initio long range corrections were not necessary. Instead, inclusion of the McConnell correction for fragments was found to be sufficient. With these parameters the algorithm produces MADs of 0.046, 0.26, 0.24 and 1.04 ppm for hydrogens, carbons, nitrogens and oxygens respectively.

A genome-wide copy number association study of osteoporotic fractures points to the 6p25.1 locus.

BACKGROUND: Osteoporosis is a systemic skeletal disease characterised by reduced bone mineral density and increased susceptibility to fracture; these traits are highly heritable. Both common and rare copy number variants (CNVs) potentially affect the function of genes and may influence disease risk. AIM: To identify CNVs associated with osteoporotic bone fracture risk. METHOD: We performed a genome-wide CNV association study in 5178 individuals from a prospective cohort in the Netherlands, including 809 osteoporotic fracture cases, and performed in silico lookups and de novo genotyping to replicate in several independent studies. RESULTS: A rare (population prevalence 0.14%, 95% CI 0.03% to 0.24%) 210 kb deletion located on chromosome 6p25.1 was associated with the risk of fracture (OR 32.58, 95% CI 3.95 to 1488.89; p = 8.69 × 10(-5)). We performed an in silico meta-analysis in four studies with CNV microarray data and the association with fracture risk was replicated (OR 3.11, 95% CI 1.01 to 8.22; p = 0.02). The prevalence of this deletion showed geographic diversity, being absent in additional samples from Australia, Canada, Poland, Iceland, Denmark, and Sweden, but present in the Netherlands (0.34%), Spain (0.33%), USA (0.23%), England (0.15%), Scotland (0.10%), and Ireland (0.06%), with insufficient evidence for association with fracture risk. CONCLUSIONS: These results suggest that deletions in the 6p25.1 locus may predispose to higher risk of fracture in a subset of populations of European origin; larger and geographically restricted studies will be needed to confirm this regional association. This is a first step towards the evaluation of the role of rare CNVs in osteoporosis.

Reproducibility and Diagnostic Accuracy of Kellgren-Lawrence Grading for Osteoarthritis Using Radiographs and Dual-Energy X-ray Absorptiometry Images.

Advances in image quality from modern dual-energy X-ray absorptiometry (DXA) scanners now allow near radiograph-like quality images at a low radiation dose. This opens potential new applications for the use of DXA scanners to study other musculoskeletal conditions, such as osteoarthritis, which is often investigated by visual assessment of radiographs. Together, osteoporosis and osteoarthritis are the 2 most common musculoskeletal conditions, both of which primarily affect older people. The aim of this study was to determine whether Kellgren-Lawrence grading of DXA images can be used to grade hip osteoarthritis as effectively as radiographs. People who had attended for recent pelvic radiographs underwent DXA of hips (50 hips from 25 people) using a GE Healthcare iDXA scanner. Three observers assigned Kellgren-Lawrence grades to each image, and grading was repeated at least 1 week apart. Intraobserver and interobserver reliability for radiographs and DXA images were calculated using quadratic-weighted kappa (QWK). People were recalled 12 months later, and the tests were repeated with both the radiograph and DXA scans taken within 2 weeks of each other. Hip DXA intraobserver reproducibility achieved a QWK range of 0.88-0.95 and interobserver reproducibility of 0.85-0.88, similar to QWK from hip radiographs. Intraobserver reliability between subject-matched radiograph and iDXA images revealed QWK ranging between 0.80 and 0.88. Reproducibility of hip osteoarthritis grading using DXA was comparable with that of radiographs in this study and similar to repeatability scores previously published in literature. Given the lower radiation dose and the opportunity to simultaneously investigate osteoporosis, DXA presents an attractive imaging option for osteoarthritis.

The characterisation and determinants of quality of life in ANCA associated vasculitis.

OBJECTIVES: To contextualise and identify the determinants of poor health related quality of life (QOL) among patients with antineutrophil cytoplasm antibody (ANCA) associated vasculitis (AAV). METHODS: A multicentre AAV case-control study was conducted using two matched groups of population and chronic disease controls. Measures of physical and mental QOL as well as putative bio-psychosocial determinants of QOL impairment were collected. Concurrently, putative clinical QOL determinants were recorded. Conditional logistic regression analyses characterised group differences while multivariable logistic regression identified within-case QOL associations which were further quantified using population attributable risks (PAR). RESULTS: Cases (n=410) experienced similar QOL to chronic disease controls (n=318) (physical QOL: OR 0.7, 95% CI 0.4 to 1.1; mental QOL: OR 1.1, 95% CI 0.8 to 1.6). However, they were substantially more likely to report poor QOL compared to general population controls (n=470) (physical QOL: OR 7.0, 95% CI 4.4 to 11.1; mental QOL: OR 2.5, 95% CI 1.7 to 3.6). A few clinical, but many more bio-psychosocial factors were independently associated with poor QOL. In population terms, fatigue was found to be of principal importance (physical QOL: PAR 24.6%; mental QOL: PAR 47.4%). CONCLUSIONS: AAV patients experienced significant QOL impairment compared to the general population, but similar to those with other chronic diseases whose considerable needs are already recognised. Potentially modifiable clinical determinants have been identified; however bio-psychosocial interventions are likely to provide the greater QOL gains in this patient population.

Neural correlates of fatigue in granulomatosis with polyangiitis: a functional magnetic resonance imaging study.

OBJECTIVE: The aim of this study was to investigate the neurophysiological effects of fatigue among patients with granulomatosis with polyangiitis (GPA). METHODS: A case-control functional MRI (fMRI) study was conducted. Stable GPA subjects were recruited according to fatigue status, with those reporting fatigue defined as cases and those not defined as controls. In addition, a control group of general population subjects with idiopathic fatigue were studied. During fMRI, all participants performed a fatigue-inducing cognitive task. Functional data were acquired with a 3 T MRI scanner during periods of task activity and rest. Analyses of the differences in blood oxygen level dependent (BOLD) signal were then performed using SPM8 software and comparisons were made between case and control groups. RESULTS: GPA cases (n = 12) were demographically matched to GPA controls (n = 14) and were clinically similar apart from the higher reporting of fatigue, by design, and depressive symptoms (P = 0.0007). After adjusting for depressive symptoms, comparison of BOLD signals revealed significantly greater activation in the right thalamus, left paracentral lobule, left medial frontal gyrus and right medial globus pallidus among GPA cases. When compared with the similarly fatigued population control group (n = 13), GPA cases shared many overlapping areas of activation. However, in addition, the population control group revealed significantly greater activation elsewhere, principally the left precentral gyrus, right superior frontal gyrus and right cingulate gyrus. CONCLUSION: fMRI has identified specific differences in the neurophysiology of fatigued GPA subjects. Future application of this promising biomarker may inform the precise mechanisms of this clinically important symptom.

Markers for work disability in anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVES: ANCA-associated vasculitis (AAV) commonly affects those of working age. Since survival rates have been transformed by immunotherapeutics, the measurement of other outcomes has become increasingly relevant. Work disability is an important outcome for both patient and society that has yet to be fully evaluated in AAV. We aimed to assess employment status in AAV patients and identify putative predictors of their work disability. METHODS: A cross-sectional study was undertaken. AAV cases were recruited according to consecutive clinic attendance. Subjects completed a questionnaire that determined employment status and other psychosocial measures. Clinical factors were concurrently recorded by the attending physician. From the data of those subjects of working age, a multivariable model was developed using forward stepwise logistic regression to identify the independent associations of work disability, defined by those subjects reporting unemployment secondary to ill-health. Results are expressed as odds ratios (ORs) and 95% CIs. RESULTS: Of the 410 participants (84.4% response rate), 149 (36.7%) were employed, 197 (48.6%) retired and 54 (13.3%) unemployed secondary to ill health. Of those of working age, 26.0% were considered work disabled. Fatigue (OR 7.1, 95% CI 1.5, 33.1), depression (OR 4.4, 95% CI 1.8, 10.8), severe disease damage [Vasculitis Damage Index (VDI) > 4 (OR 3.9, 95% CI 1.01, 14.7)] and being overweight (OR 3.4, 95% CI 1.3, 8.9) were independently associated with their unemployment. CONCLUSION: A quarter of working-age AAV subjects reported unemployment as a result of ill health and are characterized by high levels of fatigue, depression, disease damage and being overweight. These potentially modifiable factors may inform future multidisciplinary interventions aimed at alleviating work disability.

Patterns of dietary intake and serum carotenoid and tocopherol status are associated with biomarkers of chronic low-grade systemic inflammation and cardiovascular risk.

Dietary modification may affect inflammatory processes and protect against chronic disease. In the present study, we examined the relationship between dietary patterns, circulating carotenoid and tocopherol concentrations, and biomarkers of chronic low-grade systemic inflammation in a 10-year longitudinal study of Scottish postmenopausal women. Diet was assessed by FFQ during 1997-2000 (n 3237, mean age 54·8 (SD 2·2) years). Participants (n 2130, mean age 66·0 (SD 2·2) years) returned during 2007-11 for follow-up. Diet was assessed by FFQ (n 1682) and blood was collected for the analysis of serum high-sensitivity C-reactive protein (hs-CRP), IL-6, serum amyloid A, E-selectin, lipid profile and dietary biomarkers (carotenoids, tocopherols and retinol). Dietary pattern and dietary biomarker (serum carotenoid) components were generated by principal components analysis. A past 'prudent' dietary pattern predicted serum concentrations of hs-CRP and IL-6 (which decreased across the quintiles of the dietary pattern; P= 0·002 and P= 0·001, respectively; ANCOVA). Contemporary dietary patterns were also associated with inflammatory biomarkers. The concentrations of hs-CRP and IL-6 decreased across the quintiles of the 'prudent' dietary pattern (P= 0·030 and P= 0·006, respectively). hs-CRP concentration increased across the quintiles of a 'meat-dominated' dietary pattern (P= 0·001). Inflammatory biomarker concentrations decreased markedly across the quintiles of carotenoid component score (P< 0·001 for hs-CRP and IL-6, and P= 0·016 for E-selectin; ANCOVA). Prudent dietary pattern and carotenoid component scores were negatively associated with serum hs-CRP concentration (unstandardised ß for prudent component: -0·053, 95% CI -0·102, -0·003; carotenoid component: -0·183, 95% CI -0·233, -0·134) independent of study covariates. A prudent dietary pattern (which reflects a diet high in the intakes of fish, yogurt, pulses, rice, pasta and wine, in addition to fruit and vegetable consumption) and a serum carotenoid profile characteristic of a fruit and vegetable-rich diet are associated with lower concentrations of intermediary markers that are indicative of CVD risk reduction.

Genome-wide association study using extreme truncate selection identifies novel genes affecting bone mineral density and fracture risk.

Osteoporotic fracture is a major cause of morbidity and mortality worldwide. Low bone mineral density (BMD) is a major predisposing factor to fracture and is known to be highly heritable. Site-, gender-, and age-specific genetic effects on BMD are thought to be significant, but have largely not been considered in the design of genome-wide association studies (GWAS) of BMD to date. We report here a GWAS using a novel study design focusing on women of a specific age (postmenopausal women, age 55-85 years), with either extreme high or low hip BMD (age- and gender-adjusted BMD z-scores of +1.5 to +4.0, n = 1055, or -4.0 to -1.5, n = 900), with replication in cohorts of women drawn from the general population (n = 20,898). The study replicates 21 of 26 known BMD-associated genes. Additionally, we report suggestive association of a further six new genetic associations in or around the genes CLCN7, GALNT3, IBSP, LTBP3, RSPO3, and SOX4, with replication in two independent datasets. A novel mouse model with a loss-of-function mutation in GALNT3 is also reported, which has high bone mass, supporting the involvement of this gene in BMD determination. In addition to identifying further genes associated with BMD, this study confirms the efficiency of extreme-truncate selection designs for quantitative trait association studies.

Lasofoxifene in postmenopausal women with osteoporosis.

BACKGROUND: The effects of lasofoxifene on the risk of fractures, breast cancer, and cardiovascular disease are uncertain. METHODS: In this randomized trial, we assigned 8556 women who were between the ages of 59 and 80 years and had a bone mineral density T score of -2.5 or less at the femoral neck or spine to receive once-daily lasofoxifene (at a dose of either 0.25 mg or 0.5 mg) or placebo for 5 years. Primary end points were vertebral fractures, estrogen receptor (ER)-positive breast cancer, and nonvertebral fractures; secondary end points included major coronary heart disease events and stroke. RESULTS: Lasofoxifene at a dose of 0.5 mg per day, as compared with placebo, was associated with reduced risks of vertebral fracture (13.1 cases vs. 22.4 cases per 1000 person-years; hazard ratio, 0.58; 95% confidence interval [CI], 0.47 to 0.70), nonvertebral fracture (18.7 vs. 24.5 cases per 1000 person-years; hazard ratio, 0.76; 95% CI, 0.64 to 0.91), ER-positive breast cancer (0.3 vs. 1.7 cases per 1000 person-years; hazard ratio, 0.19; 95% CI, 0.07 to 0.56), coronary heart disease events (5.1 vs. 7.5 cases per 1000 person-years; hazard ratio, 0.68; 95% CI, 0.50 to 0.93), and stroke (2.5 vs. 3.9 cases per 1000 person-years; hazard ratio, 0.64; 95% CI, 0.41 to 0.99). Lasofoxifene at a dose of 0.25 mg per day, as compared with placebo, was associated with reduced risks of vertebral fracture (16.0 vs. 22.4 cases per 1000 person-years; hazard ratio, 0.69; 95% CI, 0.57 to 0.83) and stroke (2.4 vs. 3.9 cases per 1000 person-years; hazard ratio, 0.61; 95% CI, 0.39 to 0.96) Both the lower and higher doses, as compared with placebo, were associated with an increase in venous thromboembolic events (3.8 and 2.9 cases vs. 1.4 cases per 1000 person-years; hazard ratios, 2.67 [95% CI, 1.55 to 4.58] and 2.06 [95% CI, 1.17 to 3.60], respectively). Endometrial cancer occurred in three women in the placebo group, two women in the lower-dose lasofoxifene group, and two women in the higher-dose lasofoxifene group. Rates of death per 1000 person-years were 5.1 in the placebo group, 7.0 in the lower-dose lasofoxifene group, and 5.7 in the higher-dose lasofoxifene group. CONCLUSIONS: In postmenopausal women with osteoporosis, lasofoxifene at a dose of 0.5 mg per day was associated with reduced risks of nonvertebral and vertebral fractures, ER-positive breast cancer, coronary heart disease, and stroke but an increased risk of venous thromboembolic events. (ClinicalTrials.gov number, NCT00141323.)

Fatigue-related brain white matter changes in granulomatosis with polyangiitis.

OBJECTIVE: To determine the association between brain white matter (WM) damage and persistent fatigue among patients with granulomatosis with polyangiitis (GPA). METHODS: A case-control MRI study was conducted. Both cases, defined as GPA patients with chronic fatigue, and controls, defined as GPA patients without fatigue, underwent MRI brain scanning. Standard T1, T2 and FLAIR images were acquired and Scheltens white matter hyperintensity scores (SWMHS) reported in order to quantify macroscopic damage. In addition, diffusion tensor imaging (DTI) data were analysed using track-based spatial statistics to measure structural integrity and thus microscopic damage. RESULTS: No statistically significant differences in macroscopic damage were observed between cases (n = 14) and controls (n = 14) (median SWMHS 6, interquartile range 3-7 vs median SWMHS 3.5, interquartile range 3-8; P = 0.52). Compared with controls, there were no regions of WM where cases recorded reduced structural integrity; however, significantly greater structural integrity was registered in the regions of the fornix and cingulum nerve bundles of cases (P < 0.05, corrected for multiple comparisons). CONCLUSION: This study found no evidence to suggest that GPA-related fatigue is associated with either macroscopic or microscopic damage of the WM. On the contrary, regions of significantly greater structural integrity were observed among fatigued cases, which may reflect sustained activation secondary to chronic fatigue exposure.

Effect on bone turnover markers of once-yearly intravenous infusion of zoledronic acid versus daily oral risedronate in patients treated with glucocorticoids.

OBJECTIVE: Long-term glucocorticoid use is accompanied by rapid bone loss; however, early treatment with bisphosphonates prevents bone loss and reduces fracture risk. The aim of this study was to examine the effects of two bisphosphonates, i.v. zoledronic acid (ZOL) versus oral risedronate (RIS), on bone turnover markers (BTMs) in subjects with glucocorticoid-induced osteoporosis (GIO). METHODS: Patients were randomly stratified according to the duration of pre-study glucocorticoid therapy [prevention subpopulation (ZOL, n = 144; RIS, n = 144) ≤3 months, treatment subpopulation (ZOL, n = 272; RIS, n = 273) >3 months]. Changes in ß-C-terminal telopeptides of type 1 collagen (ß-CTx), N-terminal telopeptide of type I collagen (NTx), procollagen type 1 N-terminal propeptide (P1NP) and bone-specific alkaline phosphatase (BSAP) from baseline were measured on day 10 and months 3, 6 and 12. RESULTS: At most time points, there were significantly greater reductions (P < 0.05) in the concentrations of serum ß-CTx, P1NP and BSAP and urine NTx in subjects on ZOL compared with RIS in both males and females of the treatment and prevention subpopulations. In pre- and post-menopausal women, there were significantly greater reductions in the concentrations of BTMs with ZOL compared with RIS. At 12 months, ZOL had significantly greater reductions compared with RIS (P < 0.05) for ß-CTx, P1NP, BSAP and NTx levels, independent of glucocorticoid dose. CONCLUSIONS: Once-yearly i.v. infusion of ZOL 5 mg was well tolerated in different subgroups of GIO patients. ZOL was non-inferior to RIS and even superior to RIS in the response of BTMs in GIO patients. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT00100620.

Explaining fatigue in ANCA-associated vasculitis.

OBJECTIVES: To identify the determinants of fatigue among patients with ANCA-associated vasculitis (AAV). METHODS: A multicentre cross-sectional study was conducted. Subjects fulfilling the European Medicines Agency criteria for granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis (Churg-Strauss) were approached according to consecutive clinic attendance and invited to complete a questionnaire assessing fatigue and putative biopsychosocial determinants of this symptom. Concurrently, potential clinical determinants were recorded. Independent associations of fatigue were identified using forward stepwise logistic regression modelling and their overall impact expressed as population attributable risk (PAR). RESULTS: The majority (74.8%) of participants (n = 410) reported high levels of fatigue that were found to be significantly associated with numerous biopsychosocial and clinical factors. Sleep disturbance [odds ratio (OR) 5.3, 95% CI 2.7, 10.5] and pain (OR 3.8, 95% CI 2.0, 7.3) were the strongest independent associations of fatigue and, on a population level, each was more than twice as important as any other putative determinant (PAR 18.1% and 16.5%, respectively). Female gender (OR 2.1, 95% 1.1, 4.0), elevated CRP (OR 3.7, 95% CI 1.7, 8.1) and the dysfunctional coping strategies of behavioural disengagement (OR 2.4, 95% CI 1.04, 5.6) and denial (OR 2.4, 95% CI 0.9, 6.7) were also independently associated with fatigue. CONCLUSION: The data suggest that AAV-related fatigue is multifactorial in origin. Sleep disturbance and pain were found to be most important, although inflammation, as measured by CRP, was also associated. This study has identified potentially modifiable determinants that will inform future interventions aimed at alleviating fatigue.

Molecular electrostatic potentials by systematic molecular fragmentation.

A simple method is presented for estimating the molecular electrostatic potential in and around molecules using systematic molecular fragmentation. This approach estimates the potential directly from the electron density. The accuracy of the method is established for a set of organic molecules and ions. The utility of the approach is demonstrated by estimating the binding energy of a water molecule in an internal cavity in the protein ubiquitin.

Predicting OA progression to total hip replacement: can we do better than risk factors alone using active shape modelling as an imaging biomarker?

OBJECTIVE: Previously, active shape modelling (ASM) of the proximal femur was shown to identify those individuals at highest risk of developing radiographic OA. Here we determine whether ASM predicts the need for total hip replacement (THR) independent of Kellgren-Lawrence grade (KLG) and other known risk factors. METHODS: A retrospective cohort study of 141 subjects consulting primary care with new hip pain was conducted. Pelvic radiographs taken on recruitment were assessed for KLG, centre-edge angle, acetabular depth and femoral head migration. Clinical factors (duration of pain, use of a stick and physical function) were collected by self-completed questionnaires. ASM differences between shape mode scores at baseline for individuals who underwent THR during the 5-year follow-up (n = 27) and those whose OA did not progress radiographically (n = 75) were compared. RESULTS: A 1 s.d. reduction in baseline ASM mode 2 score was associated with an 81% reduction in odds of THR (OR = 0.19, 95% CI 0.52, 0.70) after adjustment for KLG, radiographic and clinical factors. A similar reduction in odds of THR was associated with a 1 s.d. reduction in mode 3 (OR = 0.45, 95% CI 0.28, 0.71) and a 1 s.d. increase in mode 4 score (OR = 2.8, 95% CI 1.7, 4.7), although these associations were no longer significant after adjustment for KLG and clinical factors. CONCLUSION: ASM of the hip joint is a reliable early biomarker of radiographic OA severity, which can improve the ability to identify patients at higher risk of rapid progression and poor outcome even when KLG and clinical risk factors are taken into account.