Search results

Meta-analysis of genome-wide association studies confirms a susceptibility locus for knee osteoarthritis on chromosome 7q22.

18 September 2018

OBJECTIVES: Osteoarthritis (OA) is the most prevalent form of arthritis and accounts for substantial morbidity and disability, particularly in older people. It is characterised by changes in joint structure, including degeneration of the articular cartilage, and its aetiology is multifactorial with a strong postulated genetic component. METHODS: A meta-analysis was performed of four genome-wide association (GWA) studies of 2371 cases of knee OA and 35 909 controls in Caucasian populations. Replication of the top hits was attempted with data from 10 additional replication datasets. RESULTS: With a cumulative sample size of 6709 cases and 44 439 controls, one genome-wide significant locus was identified on chromosome 7q22 for knee OA (rs4730250, p=9.2 × 10⁻⁹), thereby confirming its role as a susceptibility locus for OA. CONCLUSION: The associated signal is located within a large (500 kb) linkage disequilibrium block that contains six genes: PRKAR2B (protein kinase, cAMP-dependent, regulatory, type II, β), HPB1 (HMG-box transcription factor 1), COG5 (component of oligomeric golgi complex 5), GPR22 (G protein-coupled receptor 22), DUS4L (dihydrouridine synthase 4-like) and BCAP29 (B cell receptor-associated protein 29). Gene expression analyses of the (six) genes in primary cells derived from different joint tissues confirmed expression of all the genes in the joint environment.

Maternal predictors of neonatal bone size and geometry: the Southampton Women's Survey.

18 September 2018

Early growth is associated with later risk of osteoporosis and fractures. In this study, we aimed to evaluate the relationships between maternal lifestyle and body composition and neonatal bone size, geometry and density in the offspring. Participants were recruited from the Southampton Women's Survey, a unique prospective cohort of 12,500 initially non-pregnant women aged 20-34 years, resident in Southampton, UK. These women were studied in detail before and during pregnancy, and the offspring underwent anthropometric and bone mineral assessment (using dual energy-X-ray absorptiometry) at birth. A total of 841 mother-baby pairs were studied (443 boys and 398 girls). The independent predictors of greater neonatal whole body bone area (BA) and bone mineral content included greater maternal birthweight, height, parity, triceps skinfold thickness and lower walking speed in late pregnancy. Maternal smoking was independently associated with lower neonatal bone mass. Neonatal BA adjusted for birth length (a measure of bone width) was predicted positively by maternal parity and late pregnancy triceps skinfold thickness and negatively by late pregnancy walking speed. These findings were similar in both genders. We have confirmed, in a large cohort, previous findings that maternal lifestyle and body build predict neonatal bone mineral; additionally, maternal parity and fat stores and walking speed in late pregnancy were associated with neonatal bone geometry. These findings may suggest novel public health strategies to reduce the burden of osteoporotic fracture in future generations.

Volumetric bone mineral density of the tibia is not increased in subjects with radiographic knee osteoarthritis.

18 September 2018

OBJECTIVES: Radiographic osteoarthritis (ROA) has previously been shown to be associated with an increase in areal bone mineral density (BMD) as assessed by dual energy X-ray absorptiometry (DXA). Here we have assessed volumetric bone density, size and strength by peripheral quantitative computed tomography (pQCT) in a large population-based cohort study in which knee radiographs were available. METHODS: Two hundred and ninety-five men and 288 women from the MRC Hertfordshire Cohort Study underwent weight bearing extended knee X-rays and bone density measurement of the ipsi-lateral knee using pQCT. RESULTS: Increasing radiographic grade in men but not women was associated with an increase in tibial total area at 38% site and cortical area at 14% site, but not with volumetric BMD. The tibial fracture loads as well as tibial polar strength strain index at 38% site were also increased. There were no significant associations of tibia bone area, BMD or strength with radiographic grade in women. CONCLUSION: ROA is not associated with an increase in volumetric BMD as assessed by pQCT. It is, however, associated with a significant increase in bone area and strength, indicating that the association between ROA and areal BMD is mediated through bone size rather than volumetric BMD.

OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines.

18 September 2018

PURPOSE: To develop concise, patient-focussed, up to date, evidence-based, expert consensus recommendations for the management of hip and knee osteoarthritis (OA), which are adaptable and designed to assist physicians and allied health care professionals in general and specialist practise throughout the world. METHODS: Sixteen experts from four medical disciplines (primary care, rheumatology, orthopaedics and evidence-based medicine), two continents and six countries (USA, UK, France, Netherlands, Sweden and Canada) formed the guidelines development team. A systematic review of existing guidelines for the management of hip and knee OA published between 1945 and January 2006 was undertaken using the validated appraisal of guidelines research and evaluation (AGREE) instrument. A core set of management modalities was generated based on the agreement between guidelines. Evidence before 2002 was based on a systematic review conducted by European League Against Rheumatism and evidence after 2002 was updated using MEDLINE, EMBASE, CINAHL, AMED, the Cochrane Library and HTA reports. The quality of evidence was evaluated, and where possible, effect size (ES), number needed to treat, relative risk or odds ratio and cost per quality-adjusted life years gained were estimated. Consensus recommendations were produced following a Delphi exercise and the strength of recommendation (SOR) for propositions relating to each modality was determined using a visual analogue scale. RESULTS: Twenty-three treatment guidelines for the management of hip and knee OA were identified from the literature search, including six opinion-based, five evidence-based and 12 based on both expert opinion and research evidence. Twenty out of 51 treatment modalities addressed by these guidelines were universally recommended. ES for pain relief varied from treatment to treatment. Overall there was no statistically significant difference between non-pharmacological therapies [0.25, 95% confidence interval (CI) 0.16, 0.34] and pharmacological therapies (ES=0.39, 95% CI 0.31, 0.47). Following feedback from Osteoarthritis Research International members on the draft guidelines and six Delphi rounds consensus was reached on 25 carefully worded recommendations. Optimal management of patients with OA hip or knee requires a combination of non-pharmacological and pharmacological modalities of therapy. Recommendations cover the use of 12 non-pharmacological modalities: education and self-management, regular telephone contact, referral to a physical therapist, aerobic, muscle strengthening and water-based exercises, weight reduction, walking aids, knee braces, footwear and insoles, thermal modalities, transcutaneous electrical nerve stimulation and acupuncture. Eight recommendations cover pharmacological modalities of treatment including acetaminophen, cyclooxygenase-2 (COX-2) non-selective and selective oral non-steroidal anti-inflammatory drugs (NSAIDs), topical NSAIDs and capsaicin, intra-articular injections of corticosteroids and hyaluronates, glucosamine and/or chondroitin sulphate for symptom relief; glucosamine sulphate, chondroitin sulphate and diacerein for possible structure-modifying effects and the use of opioid analgesics for the treatment of refractory pain. There are recommendations covering five surgical modalities: total joint replacements, unicompartmental knee replacement, osteotomy and joint preserving surgical procedures; joint lavage and arthroscopic debridement in knee OA, and joint fusion as a salvage procedure when joint replacement had failed. Strengths of recommendation and 95% CIs are provided. CONCLUSION: Twenty-five carefully worded recommendations have been generated based on a critical appraisal of existing guidelines, a systematic review of research evidence and the consensus opinions of an international, multidisciplinary group of experts. The recommendations may be adapted for use in different countries or regions according to the availability of treatment modalities and SOR for each modality of therapy. These recommendations will be revised regularly following systematic review of new research evidence as this becomes available.

Osteoarthritis: epidemiology.

18 September 2018

Osteoarthritis (OA) is the most common joint disorder in the world. In Western populations it is one of the most frequent causes of pain, loss of function and disability in adults. Radiographic evidence of OA occurs in the majority of people by 65 years of age and in about 80% of those aged over 75 years. In the US it is second only to ischaemic heart disease as a cause of work disability in men over 50 years of age, and accounts for more hospitalizations than rheumatoid arthritis (RA) each year. Despite this public health impact, OA remains an enigmatic condition to the epidemiologist. In this chapter, we will review the definition and classification of OA, its prevalence, incidence, risk factors and natural history.

Osteoarthritis - Preface

18 September 2018

Pamidronate: a novel treatment for the SAPHO syndrome?

18 September 2018

Safety of hormone replacement therapy (HRT) in systemic lupus erythematosus (SLE).

18 September 2018

Despite its obvious benefits, many physicians are reluctant to prescribe HRT to patients with SLE. We have performed a retrospective study in 60 postmenopausal women with SLE including 30 HRT users and 30 never users. The patients were studied for 12 months after the initiation of HRT. The two groups were well matched for disease characteristics. The HRT users experienced significant improvements in general well being, libido and depression. There was no significant difference in any other parameter measured. There was no increase in the number of thrombo-embolic events in the user group despite 7 patients having a positive thrombophilia screen. In conclusion, in stable postmenopausal SLE HRT appears well tolerated and safe.

Population-based prevalence of multiple radiographically-defined hip morphologies: the Johnston County Osteoarthritis Project.

18 September 2018

OBJECTIVE: To provide the first prevalence estimates of different radiographic hip morphologies relevant to dysplasia and femoroacetabular impingement in a well-characterized USA population-based cohort. METHODS: Cross-sectional data were from the baseline examination (1991-1997) of a large population-based prospective longitudinal cohort study (The Johnston County Osteoarthritis Project). HipMorf software (Oxford, UK) was used to assess hip morphology on anteroposterior (AP) pelvis radiographs. Weighted, sex-stratified prevalence estimates and 95% confidence intervals for four key hip morphologies (AP alpha angle, triangular index sign, lateral center edge angle (LCEA), and protrusio acetabula) were derived and further stratified by age, race and body mass index (BMI). RESULTS: A total of 5192 hips from 2596 individuals were included (31% African American, 43% male, mean age 63 years, mean BMI 29 kg/m2). Cam morphology was seen in more than 25% of men and 10% of women. Mild dysplasia was present in about 1/3 of men and women, while pincer morphology was identified in 7% of men and 10% of women. Femoral side (cam) morphologies were more common and more frequently bilateral among men, while pincer morphologies were more common in women; mixed morphologies were infrequent. African-Americans were more likely to have protrusio acetabula than whites. CONCLUSION: We report the first population-based prevalence estimates of radiographic hip morphologies relevant to femoroacetabular impingement (FAI) and dysplasia in the USA. These morphologies are very common, with ¼ men and 1/10 women having cam morphology, 1/3 of all adults having mild dysplasia, and 1/15 men and 1/10 women having pincer morphology in at least one hip.

The relationship between maternal self-efficacy, compliance and outcome in a trial of vitamin D supplementation in pregnancy.

18 September 2018

In a randomised controlled trial of vitamin D during pregnancy, we demonstrated that women with lower self-efficacy were more likely to experience practical problems with taking the trial medication and that this was associated with lower compliance and achieved 25(OH)-vitamin D concentrations. INTRODUCTION: The relationship between self-efficacy (the belief that one can carry out a behaviour), compliance with study protocol and outcome was explored within a randomised, double-blind, placebo-controlled trial of vitamin D supplementation in pregnancy. METHODS: In the Maternal Vitamin D Osteoporosis Study (MAVIDOS) trial, women with circulating plasma 25(OH)-vitamin D of 25-100 nmol/l in early pregnancy were randomised to either 1000 IU cholecalciferol/day or matched placebo from 14 weeks until delivery. Circulating 25(OH)-vitamin D concentrations were assessed at 14 and 34 weeks' gestation. A sequential sub-sample completed Schwarzer's General Self-Efficacy Scale at 14 and 34 weeks and the Problematic Experiences of Therapy Scale at 34 weeks. Women were interviewed about their experiences of the trial and interview transcripts analysed thematically. RESULTS: In 203 women, those with higher self-efficacy were less likely to experience practical problems taking the study medication (odds ratio (OR) 0.81 (95 % confidence interval (CI) 0.69-0.95), p = 0.01). Over half reported practical problems associated with poorer compliance with the protocol requiring women to take the medication daily. Compliance in women who experienced practical problems was 94 % compared with 98 % for those with no problems (p < 0.001). Poorer compliance was also associated with lower concentrations of 25(OH)-D in late pregnancy in the treatment group (β = 0.54 nmol/l (95 % CI 0.18-0.89), p = 0.003). Thematic analysis suggested common difficulties were remembering to take the medication every day and swallowing the large capsules. CONCLUSIONS: These findings suggest that differences in self-efficacy influence trial outcomes. Such information may help clinicians anticipate responses to routine vitamin D supplementation in pregnancy and identify those who may need more support to comply. TRIAL REGISTRATION: ISRCTN82927713, registered 11/04/2008.