Marian Regan

Radiographic patterns and associations of osteoarthritis of the knee in patients referred to hospital.

OBJECTIVES--To investigate differing patterns and associations of osteoarthritis of the knee in patients referred to hospital. METHODS--Two hundred and fifty two consecutive patients (161 women, 91 men; mean age 70 years, range 34-91 years) referred to hospital with osteoarthritis of the knee underwent clinical, radiographic, and synovial fluid screening. RESULTS--Radiographic changes of osteoarthritis of the knee (definite narrowing with or without osteoarthritic features) were bilateral in 85% of patients. Of 470 knees affected, 277 (59%) were affected in two compartments and 28 (6%) in three compartments. Unilateral and isolated medial tibiofemoral osteoarthritis were more common in men. Calcium pyrophosphate crystal deposition was common (synovial fluid identification in 132 (28%) knees; knee chondrocalcinosis in 76 (30%) patients) and associated with disability, bilateral, multicompartmental and severe radiographic osteoarthritis, marked osteophytosis, attrition, and cysts. Multiple clinical nodes (58 (23%) patients) and radiographic polyarticular interphalangeal osteoarthritis (66 (26%) patients) were associated with a higher frequency of inactivity pain, disability, multicompartmental and severe radiographic change. Forestiers disease predominated in men but showed no other associations. CONCLUSIONS--In a group of patients referred to hospital osteoarthritis of the knee is usually bilateral and affects more than one compartment. Severe and multicompartmental radiographic changes are associated with calcium pyrophosphate crystal deposition, nodal change, and polyarticular interphalangeal osteoarthritis.

Factors affecting radiographic progression of knee osteoarthritis.

OBJECTIVES--To evaluate the prognostic significance of patient characteristics and radiographic features at the knee for outcome of knee osteoarthritis. METHODS--This was a prospective observational study of 350 osteoarthritic knees. Clinical and radiographic data were obtained on 188 hospital referred patients (mean age 70, range 34-91 years). RESULTS--Median duration of follow up was two years (range 1-5 years). The majority of patients (48%) reported deterioration, but 23% experienced improvement in symptoms during the study period. Reported exercise tolerance remained unchanged in the majority (62%) and deteriorated in 35%. Change in at least one individual radiographic feature of osteoarthritis was seen in 252 (72%) knees: increase in joint space narrowing occurred in 52%, osteophyte in 32%, cysts in 19%, sclerosis in 14%, and attrition in 30%. Increase in Kellgren grade occurred in 137 (39%) knees. Knee effusion, osteoarthritis at multiple joint sites, and nodal change associated with change in Kellgren grade (odds ratios 1.03, 2.39, and 1.80; 95% confidence intervals (CI) 1.01 to 1.05, 1.16 to 4.93, and 1.02 to 3.17, respectively); warmth at the knee associated with change in any radiographic feature (odds ratio 2.22; 95% CI 1.19 to 4.14). Development of, or increase in, attrition and joint space narrowing associated with worsening symptoms and function and occurred with increased frequency in knees with effusions, clinical warmth and calcium pyrophosphate crystals in synovial fluid (p < 0.05). CONCLUSIONS--A high rate of change, radiographic more than clinical, was seen in osteoarthritic knees during this study. Poor clinical and radiographic outcome associated with calcium pyrophosphate crystal deposition and clinical inflammation as reflected by knee effusion and warmth.

Association between synovial fluid levels of inorganic pyrophosphate and short term radiographic outcome of knee osteoarthritis.

OBJECTIVE: To test the hypothesis that high concentrations of extracellular inorganic pyrophosphate (PPi), which associate with increased cell synthesis and turnover in cartilage, may act as a marker for structural outcome in knee osteoarthritis (OA). METHOD: One hundred and thirty five consecutive patients referred to hospital with knee OA (59 men, 76 women; mean age 71 years, range 41-88) were followed prospectively for a median of 2.5 years (interquartile range 1.75-3.0). Synovial fluid (SF) aspirated at presentation (202 OA knees: 68 bilateral, 66 unilateral) was assessed for PPi content by radiometric assay. Knee radiographs at presentation and at final review were assessed for change in global (Kellgren) and individual features (narrowing, osteophyte, sclerosis, cyst, attrition) of OA. RESULTS: The median SF PPi level was 10.5 mumol (range 0.07-72.4). At baseline, high PPi was significantly associated with presence of calcium pyrophosphate crystals, chondrocalcinosis, and bone attrition. Radiographic change was observed in 164 knees. High PPi levels were negatively associated with change in Kellgren and Lawrence grade, further narrowing, and increase in osteophyte, but positively associated with development of attrition. In the 68 patients from whom bilateral data were obtained, there was correlation between right and left knees for PPi levels, all baseline radiographic scores, and changes in radiographic features. Multiple logistic regression analysis for PPi as a continuous variable (age, gender, and patient number included in model) showed a negative correlation with change in global Kellgren and Lawrence grade (odds ratio (OR) 0.97, 95% confidence interval (CI) 0.95 to 0.99) and a positive correlation with attrition (OR 1.04, 95% CI 1.02 to 1.07). CONCLUSION: High SF levels of PPi are associated with favourable radiographic outcome in terms of progressive change in Kellgren grade. Such elevated PPi levels, however, may inhibit new bone formation and remodelling in knee OA.

Association of two loci on chromosome 2q with nodal osteoarthritis.

OBJECTIVE: To search for genetic association between microsatellite marker loci and sibling pairs with nodal osteoarthritis (NOA). METHODS: Using the affected sibling pair method of analysis, genomic DNA from 66 sib pairs with NOA was analysed for association with highly polymorphic microsatellite marker loci. The microsatellite markers were amplified using polymerase chain reaction and typed on polyacrylamide gels. RESULTS: A significant association (p < 0.05) was identified between NOA and two loci on the short arm of chromosome 2 (2q 23-35). Candidate genes for osteoarthritis in this region include: fibronectin, a glycoprotein present in the extracellular matrix of normal cartilage; the alpha 2 chain of collagen type V, a major constituent of bone; and the interleukin-8 receptor, important in the regulation of neutrophil activation and chemotaxis. CONCLUSIONS: The chromosomal region 2q 23-35 requires further detailed study in NOA. Confirmation of these findings in large independent data sets and further analysis of candidate genes in this region will be important in unravelling the molecular basis for this common disease.

Health-related utility values of patients with primary Sjögren's syndrome and its predictors

Objectives EuroQoL-5 dimension (EQ-5D) is a standardised preference-based tool for measurement of health-related quality of life and EQ-5D utility values can be converted to quality-adjusted life years (QALYs) to aid cost-utility analysis. This study aimed to evaluate the EQ-5D utility values of 639 patients with primary Sjögrens syndrome (PSS) in the UK. Methods Prospective data collected using a standardised pro forma were compared with UK normative data. Relationships between utility values and the clinical and laboratory features of PSS were explored. Results The proportion of patients with PSS reporting any problem in mobility, self-care, usual activities, pain/discomfort and anxiety/depression were 42.2%, 16.7%, 56.6%, 80.6% and 49.4%, respectively, compared with 5.4%, 1.6%, 7.9%, 30.2% and 15.7% for the UK general population. The median EQ-5D utility value was 0.691 (IQR 0.587–0.796, range −0.239 to 1.000) with a bimodal distribution. Bivariate correlation analysis revealed significant correlations between EQ-5D utility values and many clinical features of PSS, but most strongly with pain, depression and fatigue (R values>0.5). After adjusting for age and sex differences, multiple regression analysis identified pain and depression as the two most important predictors of EQ-5D utility values, accounting for 48% of the variability. Anxiety, fatigue and body mass index were other statistically significant predictors, but they accounted for <5% in variability. Conclusions This is the first report on the EQ-5D utility values of patients with PSS. These patients have significantly impaired utility values compared with the UK general population. EQ-5D utility values are significantly related to pain and depression scores in PSS.

Estimating Indirect Costs in Primary Sjogren's Syndrome

Objective. To estimate the indirect costs associated with primary Sjögren’s syndrome (pSS) compared with rheumatoid arthritis (RA) and community controls. Methods. Data were obtained from 84 women patients with pSS as part of a study to develop a systemic activity measure, from 87 consecutive women patients with RA attending a hospital clinic, and from 96 women community controls on a general practice list. A modified economic component of the Stanford Health Assessment Questionnaire was used to assess lost productivity. Results. Using a conservative model, the estimated total annual indirect costs (95% CI) were £7677 (£5560, £9794) for pSS, £10,444 (£8206, £12,681) for RA, and £892 (£307, £1478) for controls. Using a model that maximizes the estimates, the equivalent figures were £13,502 (£9542, £17,463), £17,070 (£13,112, £21,028), and £3382 (£2187, £4578), respectively. These were all significantly greater at p < 0.001 for patient groups than for the control group. Conclusion. pSS is associated with significantly increased indirect costs equivalent to 69%–83% of that for patients with RA. This needs to be taken into account when evaluating the overall economic consequences of pSS.

Evidence for genetic anticipation in nodal osteoarthritis

OBJECTIVE Evidence was sought for genetic anticipation (disease occurring at an earlier age in subsequent generations, with increasing severity) in nodal osteoarthritis (NOA). METHODS Age at symptom onset and disease severity was compared within 30 parent/offspring pairs with NOA. Correlation between the offspring age of disease onset and the parental age at conception was also assessed. RESULTS The age at onset of nodal symptoms was earlier in the offspring (43 years (95% confidence intervals (CI) 38 to 47) v 61 (CI 58 to 65); mean difference 18 years (CI 13 to 22): p< 0.001) as was large joint symptom onset (48 years (CI 41 to 55) v 67 (CI 61 to 73); mean difference 20 years (CI 13 to 27): p< 0.01). A negative correlation existed between age of offspring symptom onset and parental age at conception. Fifteen (50%) offspring had similar or more extensive disease than their parents. CONCLUSIONS These results suggest genetic anticipation occurs in NOA and if confirmed a search for trinucleotide repeats is warranted.

Soluble molecule profiling and network analysis of primary Sjögren's Syndrome patient serum

Background Primary Sjogren’s Syndrome (pSS) is a chronic autoimmune syndrome characterised by sicca symptoms, fatigue, musculoskeletal pain and an increased risk of lymphoma. Patient populations are notably heterogeneous in their symptoms, adding to the challenge of pSS research. This study utilises serum samples from the UK Primary Sjogren’s Syndrome Registry (UKPSSR) a large cohort of clinically well-characterised pSS patients and healthy controls with an aim to determine whether serum cytokines, chemokines and adhesion molecules may be used to differentiate pSS patients from healthy controls.

Fatigue in primary Sjögren's syndrome is associated with lower levels of proinflammatory cytokines.

Objectives This article reports relationships between serum cytokine levels and patient-reported levels of fatigue, in the chronic immunological condition primary Sjögrens syndrome (pSS). Methods Blood levels of 24 cytokines were measured in 159 patients with pSS from the United Kingdom Primary Sjögrens Syndrome Registry and 28 healthy non-fatigued controls. Differences between cytokines in cases and controls were evaluated using Wilcoxon test. Patient-reported scores for fatigue were evaluated, classified according to severity and compared with cytokine levels using analysis of variance. Logistic regression was used to determine the most important predictors of fatigue levels. Results 14 cytokines were significantly higher in patients with pSS (n=159) compared to non-fatigued healthy controls (n=28). While serum levels were elevated in patients with pSS compared to healthy controls, unexpectedly, the levels of 4 proinflammatory cytokines—interferon-γ-induced protein-10 (IP-10) (p=0.019), tumour necrosis factor-α (p=0.046), lymphotoxin-α (p=0.034) and interferon-γ (IFN-γ) (p=0.022)—were inversely related to patient-reported levels of fatigue. A regression model predicting fatigue levels in pSS based on cytokine levels, disease-specific and clinical parameters, as well as anxiety, pain and depression, revealed IP-10, IFN-γ (both inversely), pain and depression (both positively) as the most important predictors of fatigue. This model correctly predicts fatigue levels with reasonable (67%) accuracy. Conclusions Cytokines, pain and depression appear to be the most powerful predictors of fatigue in pSS. Our data challenge the notion that proinflammatory cytokines directly mediate fatigue in chronic immunological conditions. Instead, we hypothesise that mechanisms regulating inflammatory responses may be important.

Eligibility for clinical trials in primary Sjogren's syndrome: lessons from the UK Primary Sjogren's Syndrome Registry.

OBJECTIVE To identify numbers of participants in the UK Primary Sjögrens Syndrome Registry (UKPSSR) who would fulfil eligibility criteria for previous/current or potential clinical trials in primary SS (pSS) in order to optimize recruitment. METHODS We did a retrospective analysis of UKPSSR cohort data of 688 participants who had pSS with evaluable data. RESULTS In relation to previous/current trials, 75.2% fulfilled eligibility for the Belimumab in Subjects with Primary Sjögrens Syndrome study (Belimumab), 41.4% fulfilled eligibility for the Trial of Remicade in primary Sjögrens syndrome study (Infliximab), 35.4% for the Efficacy of Tocilizumab in Primary Sjögrens Syndrome study (Tocilizumab), 31.6% for the Tolerance and Efficacy of Rituximab in Sjögrens Disease study (Rituximab), 26.9% for the Trial of anti-B-cell therapy in pSS study (Rituximab) and 26.6% for the Efficacy and Safety of Abatacept in Patients With Primary Sjögrens Syndrome study (Abatacept). If recent measures of outcome, such as the EULAR Sjögrens Syndrome Patient Reported Index (ESSPRI) score ⩾5 (measure of patient symptoms) and the EULAR Sjögrens Syndrome Disease Activity Index (ESSDAI) score ⩾5 (measure of systemic disease activity) are incorporated into a study design, with requirements for an unstimulated salivary flow >0 and anti-Ro positivity, then the pool of eligible participants is reduced to 14.3%. CONCLUSION The UKPSSR identified a number of options for trial design, including selection on ESSDAI ⩾5, ESSPRI ⩾5 and serological and other parameters.