Racial origin and its effect on disease expression and HLA-DRB1 types in patients with rheumatoid arthritis: a matched cross-sectional study

Clinical Implications of Shared Epitope and Anti-citrullinated Peptide Antibody in Patients With Rheumatoid Arthritis

Objective

The shared epitope (SE) and anti-citrullinated peptide antibody (ACPA) are involved in the pathogenesis of rheumatoid arthritis (RA). This study evaluated the clinical implications of SE and ACPA in terms of disease manifestation and response to biologic disease modifying anti-rheumatic drugs (DMARDs).

Methods

Patients with identified human leukocyte antigen (HLA)-DRB1 alleles were included to compare the clinical characteristics and drug survival rate of tumor necrosis factor (TNF) inhibitors or abatacept based on the presence of SE and ACPA.

Results

Of the 533 patients with identified HLA-DRB1 alleles, 329 patients (61.7%) with SE alleles showed higher disease activity and erosive changes compared to patients without SE alleles. SE-positive patients were more likely to start biologic (b-) or targeted synthetic DMARDs (tsDMARDs) within the first 5 years (p=0.020). The presence of SE, smoking, dyslipidemia, and higher erythrocyte sedimentation rate were independently associated with the initiation of b- or tsDMARDs (p=0.016, 0.028, 0.031, and 0.001, respectively). The presence of SE and ACPA did not affect the drug survival rate of TNF inhibitors, whereas the abatacept retention rate was higher in ACPA-positive patients (p=0.024).

Conclusion

The presence of SE affected disease characteristics and prognosis in Korean patients with RA without a significant impact on drug survival rate of TNF inhibitors and abatacept. ACPA positivity was associated with abatacept drug retention, suggesting that abatacept may be helpful in ACPA-positive patients than in ACPA-negative patients.

Tofacitinib for the treatment of rheumatoid arthritis: a real-world study in China

Tofacitinib has only been available in China for 2 years to treat rheumatoid arthritis (RA). Our purpose was to compare real-world effectiveness of tofacitinib with that of disease-modifying anti-rheumatic drugs (DMARDs) in Chinese patients with RA. The records of patients with RA treated at Guangdong Provincial People's Hospital between July 2017 and September 2019 were retrospectively reviewed. Patients were divided into those treated with tofacitinib, biological DMARDs (bDMARDs), and conventional synthetic DMARDs (csDMARDs). Clinical disease activity index (CDAI), simplified disease activity index (SDAI), health assessment questionnaire-disability index (HAQ-DI), visual analog scale (VAS) pain score, patient global assessment of disease activity (PtGA), physician global assessment of disease activity (PhGA), and swollen joint and tender joint count were compared among the groups up to 12 months of treatment. A total of 150 patients were included: 63 were treated with tofacitinib, 48 with bDMARDs, and 39 with csDMARDs. Tofacitinib was first-line treatment in 26.98% of patients, second-line treatment in 49.21%, and third-line treatment in 26.98%. Patients in the tofacitinib group had significantly higher disease duration (6.11 ± 6.97 years) than those in the other groups. All disease indices in the three groups decreased with time, indicating improvement of symptoms, with no differences among the groups at 12 months. Tofacitinib appeared to improve symptoms more rapidly than other treatments; however, differences in disease indices were not significant. This real-world study suggests that tofacitinib is rapidly effective and that the effects are sustained after 12 months in Chinese patients with RA.

A clinical and radiographic comparison of patients with psoriatic arthritis from different ethnic backgrounds

OBJECTIVES

There are few papers concerning ethnic differences in disease expression in PsA, which may be influenced by a number of genetic, lifestyle and cultural factors. This article aims to compare clinical and radiographic phenotypes in people of South Asian (SA) and North European (NE) origin with a diagnosis of PsA.

METHODS

This was a cross-sectional observational study recruiting patients of SA and NE origin from two hospitals in a well-defined area in the North of England.

RESULTS

A total of 58 SA and 48 NE patients were recruited. SA patients had a more severe clinical phenotype with more tender (median 5 vs 2) and swollen (median 1 vs 0) joints, more severe enthesitis (median 3 vs 1.5), more patients with dactylitis (24% vs 8%), more severe skin disease (median PASI 2.2 vs 1) and worse disease activity as measured by the composite Psoriatic Arthritis Disease Activity Score (mean 4.5 vs 3.6). With regards to patient-completed measures, SA patients had worse impact with poorer quality of life and function (mean HAQ 0.9 vs 0.6; mean PsAQoL 10.8 vs 6.2; mean 36-item short form physical component score 33.5 vs 38.9). No significant differences in current MTX and biologics use were found.

CONCLUSIONS

SA patients had a worse clinical phenotype and worse impact of disease than NE patients. Further studies are needed to confirm and explore the reasons behind these differences.

Association of anti-cyclic citrullinated peptide antibodies and rheumatoid factor isotypes with HLA-DRB1 shared epitope alleles in Egyptian rheumatoid arthritis patients

INTRODUCTION

The most common genetic risk factor for rheumatoid arthritis (RA) is human leucocyte antigen DRB1 (HLA-DRB1) shared epitope (SE).

AIM

To investigate the relationship between anti-cyclic citrullinated peptide (anti-CCP), rheumatoid factor (RF), immunoglobulin (Ig)G, IgM and IgA and HLA-DRB1 SE among Egyptian patients with RA.

METHODS

Serum levels of anti-CCP antibodies and RFIgG, RFIgM, RFIgA were assayed using enzyme-linked immunosorbent assay for 157 Egyptian RA patients and 150 healthy controls attending the outpatient clinics of National Research Center and Kasr El Aini Hospital. HLA-DRB1 genotyping was performed by the DynalAllSetTM polymerase chain reaction (PCR) single specific primer low-resolution typing kits. Amplified PCR product was checked using 3% agarose gel.

RESULTS

HLA-DRB1-SE was found among 129 (82.2%) RA patients and 67 (44.7%) controls (odds ratio [OR] 5.7, CI 3.4-9.6, P < .0001). The risk of RA development was higher with the presence of SE two alleles (OR 11.6, P < .0001), while the OR for 1 copy SE allele was 4.4 (P < .0001). HLA-DRB1-SE was significantly associated with positive as well as negative anti-CCP and RF isotypes. The stronger association was with anti-CCP positivity with OR 11 (5.1-23.6), P < .0001. Furthermore, the risk of development of positive anti-CCP and RF isotypes was higher with the presence of 2 copies of SE alleles than with 1 copy.

CONCLUSION

The prevalence of HLA-DRB1-SE is high in Egyptian RA patients. The role of SE in RA patients is most probably related to the development of anti-CCP positive RA rather than the development of anti-CCP positivity.

Delays between the onset of symptoms and first rheumatology consultation in patients with rheumatoid arthritis in the UK: an observational study

OBJECTIVE

To investigate delays from symptom onset to rheumatology assessment for patients with a new onset of rheumatoid arthritis (RA) or unclassified arthritis.

METHODS

Newly presenting adults with either RA or unclassified arthritis were recruited from rheumatology clinics. Data on the length of time between symptom onset and first seeing a GP (patient delay), between first seeing a general practitioner (GP) and being referred to a rheumatologist (general practitioner delay) and being seen by a rheumatologist following referral (hospital delay) were captured.

RESULTS

822 patients participated (563 female, mean age 55 years). The median time between symptom onset and seeing a rheumatologist was 27.2 weeks (IQR 14.1-66 weeks); only 20% of patients were seen within the first 3 months following symptom onset. The median patient delay was 5.4 weeks (IQR 1.4-26.3 weeks). Patients who purchased over-the-counter medications or used ice/heat packs took longer to seek help than those who did not. In addition, those with a palindromic or an insidious symptom onset delayed for longer than those with a non-palindromic or acute onset. The median general practitioner delay was 6.9 weeks (IQR 2.3-20.3 weeks). Patients made a mean of 4 GP visits before being referred. The median hospital delay was 4.7 weeks (IQR 2.9-7.5 weeks).

CONCLUSION

This study identified delays at all levels in the pathway towards assessment by a rheumatologist. However, delays in primary care were particularly long. Patient delay was driven by the nature of symptom onset. Complex multi-faceted interventions to promote rapid help seeking and to facilitate prompt onward referral from primary care should be developed.

Predictors of disease activity and structural progression after treatment with adalimumab plus methotrexate or continued methotrexate monotherapy in patients with early rheumatoid arthritis and suboptimal response to methotrexate

Objectives

Methotrexate is considered to be first-line therapy for rheumatoid arthritis (RA). However, a substantial proportion of treated patients do not achieve the desired goals of therapy. This analysis aimed to identify predictors of insufficient response to methotrexate in patients with early RA.

Methods

The Optimal Protocol for Treatment Initiation with Methotrexate and Adalimumab (OPTIMA) and PREMIER studies in patients with RA for <1 and <3 years, respectively, examined the efficacy of methotrexate and adalimumab in methotrexate-naive patients. This post hoc analysis included patients for whom initial methotrexate monotherapy was not successful after 6 months. Candidate predictors of insufficient response and clinically relevant radiographic progression (CRRP) included demographics, baseline disease characteristics and time-averaged disease variables over a 12-week interval. In OPTIMA, adalimumab was added to therapy after insufficient treatment response; in PREMIER, initial methotrexate therapy was continued; clinical, functional and radiologic outcomes were assessed after 1 year.

Results

Baseline 28-joint Disease Activity Score based on C-reactive protein (DAS28(CRP)) and time-averaged DAS28(CRP) over 4, 8 and 12 weeks were the strongest predictors of insufficient response to methotrexate and CRRP. Addition of adalimumab to methotrexate therapy was associated with better clinical, functional and radiographic outcomes after 1 year compared with continuing on methotrexate monotherapy.

Conclusions

In patients with early RA, baseline disease characteristics and early disease activity can predict response to methotrexate treatment and radiographic progression at 6 months. The addition of adalimumab at 6 months after methotrexate failure is associated with improved outcomes. These results support treatment-to-target strategies and timely adaptation of therapy in patients with early RA.

Trial registration number

NCT00420927, NCT00195663; Post-results.

Citrullination only infrequently impacts peptide binding to HLA class II MHC

It has been hypothesized that HLA class II alleles associated with rheumatoid arthritis (RA) preferentially present self-antigens altered by post-translational modification, such as citrullination. To understand the role of citrullination we tested four RA-associated citrullinated epitopes and their corresponding wild-type version for binding to 28 common HLA class II. Binding patterns were variable, and no consistent impact of citrullination was identified. Indeed, in one case citrullination significantly increased binding compared to the WT peptide, in another citrullination was associated with a reduction in promiscuity by 40%. For a more comprehensive analysis, we tested over 200 citrullinated peptides derived from vimentin and collagen II for their capacity to bind the RA-associated shared epitope alleles DRB1*01:01 and DRB1*04:01. The overall effect of citrullination on binding was found to be relatively minor, and only rarely associated with 3-fold increases or decreases in affinity. Previous studies have suggested that citrullination of MHC anchor residues, in particular P4, is associated with generation of novel RA-associated epitopes. However, analysis of the predicted MHC-binding cores of all peptides tested found that in modified peptides with increased binding affinity the citrullinated residue was predicted to occupy an anchor position in only a minority of cases. Finally, we also show that identification of citrullinated peptide binders could be facilitated by using the NetMHCIIpan 3.1 algorithm, representing citrullination as a wildcard. Our studies identify a total of 117 citrullinated peptides that bound RA-associated alleles with an affinity of 1000 nM or better.

Effect of ethnicity on disease activity and physical function in psoriatic arthritis in a multiethnic Asian population

Geographic differences in manifestation of psoriatic arthritis (PsA) could be related to differences in genetic or environmental factors. We aimed to compare the disease activity and functional status using validated outcome measures among patients with PsA of different ethnicities living in the same environment. We performed a cross-sectional study on consecutive patients with PsA classified by the Classification Criteria for Psoriatic Arthritis (CASPAR) criteria from a single center. Sociodemographic data, clinical variables, and patient-reported outcomes were collected using a standardized protocol. Disease activities were assessed by validated composite scores: clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA), Composite Psoriatic Disease Activity Index (CPDAI), and minimal disease activity (MDA). Physical function was assessed with Health Assessment Questionnaire (HAQ) and the Medical Outcome Study Short-Form 36 (SF36) physical function subscales. Linear regression analyses were performed to identify variables associated with disease activities and physical function. Ninety-eight patients (51.5%, men) with mean (±SD) age and duration of PsA of 51.5 ± 13.8 and 5.5 ± 8.4 years were recruited. Indian was overrepresented compared with the national distribution of ethnicities. Compared to Chinese, Indian patients were more likely to be using biological therapies, have higher tender joint count, and worse enthesitis. Higher proportion of Indians had higher disease activity categories measured by cDAPSA, CPDAI, and MDA and had poorer physical function. In the multivariable analysis, ethnicity was significantly associated with HAQ and SF36-PF. Compared to Chinese, Indians with PsA living in the same environment had worse disease activity and physical function measured by validated outcomes.

Extraarticular manifestations of rheumatoid arthritis in a multiethnic cohort of predominantly Hispanic and Asian patients

We conducted a study to determine the prevalence of extraarticular manifestations (ExRA) in a cohort of predominantly Hispanic and Asian patients with rheumatoid arthritis (RA), to identify factors associated with the development of ExRA, and to compare the prevalence of ExRA between Hispanic and Asian patients. Patients with RA followed in the outpatient rheumatology clinics of a public hospital were included if they were aged ≥18 years and met the 1987 American College of Rheumatology criteria for the diagnosis of RA. We performed a cross-sectional analysis in which patients with ExRA were identified based on predefined criteria. We compared sociodemographic and clinical characteristics in patients with and without ExRA. Multivariate logistic regression was used to examine the association between sociodemographic variables, clinical characteristics, and the presence of ExRA. The prevalence of ExRA was 21.5%, and the most common manifestations were subcutaneous nodules (17.2%) and interstitial lung disease (3.6%). Hispanic patients were significantly more likely to develop ExRA than Asian patients (odds ratio, 2.53; 95% confidence interval, 1.26-5.09). The development of ExRA was also associated with disease duration, male sex, and seropositivity for serum rheumatoid factor.

Shared epitope alleles remain a risk factor for anti-citrullinated proteins antibody (ACPA)--positive rheumatoid arthritis in three Asian ethnic groups

Background

To investigate the associations between HLA-DRB1 shared epitope (SE) alleles and rheumatoid arthritis in subsets of rheumatoid arthritis defined by autoantibodies in three Asian populations from Malaysia.

Methods

1,079 rheumatoid arthritis patients and 1,470 healthy controls were included in the study. Levels of antibodies to citrullinated proteins (ACPA) and rheumatoid factors were assessed and the PCR-SSO method was used for HLA-DRB1 genotyping.

Results

The proportion of ACPA positivity among Malay, Chinese and Indian rheumatoid arthritis patients were 62.9%, 65.2% and 68.6%, respectively. An increased frequency of SE alleles was observed in ACPA-positive rheumatoid arthritis among the three Asian ethnic groups. HLA-DRB1*10 was highly associated with rheumatoid arthritis susceptibility in these Asian populations. HLA-DRB1*0405 was significantly associated with susceptibility to rheumatoid arthritis in Malays and Chinese, but not in Indians. HLA-DRB1*01 did not show any independent effect as a risk factor for rheumatoid arthritis in this study and HLA-DRB1*1202 was protective in Malays and Chinese. There was no association between SE alleles and ACPA- negative rheumatoid arthritis in any of the three Asian ethnic groups.

Conclusion

The HLA-DRB1 SE alleles increase the risk of ACPA-positive rheumatoid arthritis in all three Asian populations from Malaysia.

Causes of DMARD withdrawal following ADR within 6 months of initiation among Indian rheumatoid arthritis patients

The present study was conducted in Indian rheumatoid arthritis (RA) patients prescribed disease-modifying anti-rheumatic drugs (DMARDs) to determine the incidence and type of adverse drug reactions (ADRs) leading to their withdrawal in the initial 6 months of therapy. This was considered important as pharmacogenetic variations in the pattern of RA in different populations and genetic differences in efficacy and safety to drugs demand separate studies to be conducted in different populations. Hospital records were used to identify 1,000 consecutive patients with RA fulfilling the American College of Rheumatology criteria and having at least 6-month follow-up. Age, gender, duration of arthritis, drug usage and ADR-related drug withdrawal were recorded from the charts. Most of the patients were put on single DMARD. Combined use of DMARD was less frequent and non-use of DMARD was common; however, disease control was good. The commonest DMARD used in our hospital was hydroxychloroquine 444 (44%) and the commonest combination used was methotrexate with hydroxychloroquine by 55 (6%). Sulphasalazine use showed preference to young and males. Supportive drugs used were NSAIDs by 883 (88%), corticosteroids by 646 (65%), paracetamol by 594 (59%) and amitriptyline by 88 (9%). Incidence of ADR-related DMARD withdrawal was maximum with leflunomide 2/15 (13.33%) followed by methotrexate 9/116 (7.76%), sulphasalazine 6/185 (3.24%), chloroquine 3/131 (2.29%) and hydroxychloroquine 8/444 (1.8%). Severity and symptomatology of disease, genetic pattern of patients, financial status, previous experience of the clinicians and patients, availability of drugs, patient expectations and compliance were the main factors that lead to a difference in pattern of therapy in our patients compared to other population.

Self-management strategies used during flares of rheumatoid arthritis in an ethnically diverse population

OBJECTIVES

 Effective management of flares of rheumatoid arthritis (RA) can improve symptoms and may delay disease progression. The practice of rheumatologists in managing a flare has been studied, but patients' experiences of, and responses to, disease flares remain poorly defined. This study aimed to address this issue.

METHODS

 Semi-structured interviews were conducted with 21 patients from an ethnically diverse population who had suffered a recent RA flare. Open questions were asked regarding patients' definitions of a flare, causal attribution, self-management strategies, their triggers to consult health professionals, and the information they had received about RA flares from health professionals. Transcripts were studied using the grounded theory approach to identify themes.

RESULTS

 Flares were usually described as worsening joint pain and swelling. Over-use of joints was identified as the most common cause of a flare, and commonly used self-management strategies included rest, gentle exercise and warming the joints. There was some variation in causal attribution and self-management with ethnicity.

CONCLUSIONS

 This study identified a link between causal attribution of flares and the resultant self-management strategies. A perceived trigger of the flare in some patients formed a focus for their self-management strategies, whereas those who could not identify a cause aimed mainly to alleviate symptoms. A better understanding of patients' perspective in the context of disease flares will allow the development of educational programmes to facilitate more effective self-management of this important manifestation of disease.

Effect of ethnic origin (Caucasians versus Turks) on the prevalence of rheumatic diseases: a WHO-ILAR COPCORD urban study in Iran

The objective of this study was to compare the prevalence of musculoskeletal complaints and rheumatic disorders in Caucasians and Turks in an identical environment. Subjects were selected randomly for an interview from Tehran's 22 districts. The Community Oriented Program for Control of Rheumatic Diseases questionnaire was filled in, positive cases were examined, and if needed, laboratory or X-ray tests were performed. A total of 4,096 houses were visited, and 10,291 persons were interviewed. They were 71.4% Caucasians and 23.1% Turks with similar distribution of age and gender. Musculoskeletal complaints of the past 7 days were detected in 40.8% of Caucasians and 45.5% of Turks (p < 0.001). In Caucasians, the total of musculoskeletal complaints in men was 33.8% (95% CI, 31.4-36.2%) versus 48.3% in women (95% CI, 45.7-50.8%). In Turks, the total of musculoskeletal complaints in men was 36.6% (95% CI, 32.2-41.1%) versus 55.8% in women (95% CI, 55.8-60.6%). The data of Caucasians versus Turks were as follows: knee pain 20.2% (95% CI, 18.2-22.1) versus 24.1% (95% CI, 20.5-27.6), with p < 0.001; dorso-lumbar spine pain 15.1% (95% CI, 13.6-16.6) versus 18.4% (95% CI, 15.1-21.8), with p < 0.001; shoulder pain 10.7% (95% CI, 9.4-11.9) versus 12.3% (95% CI, 9.7-14.8), with p = 0.025; osteoarthritis 14.1% (95% CI, 12.8-15.2) versus 16.4% (95% CI, 14.3-18.6), p = 0.04; and knee osteoarthritis 12.3% (95% CI, 11.8-14.1) versus 15.3% (95% CI, 13.3-17.4), with p < 0.001). There were no significant differences regarding the prevalence of soft tissue rheumatism, rheumatoid arthritis, ankylosing spondylitis, Behcet's disease, fibromyalgia, and gout. Although musculoskeletal complaints were more frequent in Turks than in Caucasians, the prevalence of rheumatic disorders was rather similar except for knee osteoarthritis.

Clinical and radiological features of rheumatoid arthritis in British black Africans

The objective of this study was to determine whether radiographic damage is different in British black African patients with rheumatoid arthritis compared to Caucasian patients. Data on demographics, disease- and disability-related variables were obtained from all black African patients and their age-, gender- and disease-duration-matched Caucasian controls. After all features identifying the patients were concealed, X-rays of hands and feet were scored by using the Sharp/van der Heijde method. Data were analysed using Mann-Whitney U test, t test and chi (2) test. Sixty-four patients (32 in each ethnic group) were studied. The median age was 52 years and median disease duration 6 years. Seventy-two percent of patients were female. Black Africans and Caucasians did not differ significantly in rheumatoid factor positivity, disease-modifying anti-rheumatic drugs and biological treatment use. British black African patients had significantly more tender joints and disability. Joint space narrowing was significantly greater in Caucasian patients [48 (27-85) vs 56 (34-107), p = 0.01]. Caucasian patients had more number of erosions (172 vs 220) and higher erosion score; however, the difference in the erosion scores was not statistically significant [2 (0-48) vs 4.5 (0-46), p = 0.17]. Radiographic damage was less severe in black African patients with rheumatoid arthritis compared to their age-, gender- and disease-duration-matched Caucasian controls. A large prospective study is required to confirm the findings of this study and to establish the factors which might be accountable for any differences in the expression of rheumatoid arthritis in this ethnic group.

Analysis of Fcgamma receptor haplotypes in rheumatoid arthritis: FCGR3A remains a major susceptibility gene at this locus, with an additional contribution from FCGR3B

The Fcγ receptors play important roles in the initiation and regulation of many immunological and inflammatory processes, and genetic variants (FCGR) have been associated with numerous autoimmune and infectious diseases. The data in rheumatoid arthritis (RA) are conflicting and we previously demonstrated an association between FCGR3A and RA. In view of the close molecular proximity with FCGR2A, FCGR2B and FCGR3B, additional polymorphisms within these genes and FCGR haplotypes were examined to refine the extent of association with RA. Biallelic polymorphisms in FCGR2A, FCGR2B and FCGR3B were examined for association with RA in two well characterized UK Caucasian and North Indian/Pakistani cohorts, in which FCGR3A genotyping had previously been undertaken. Haplotype frequencies and linkage disequilibrium were estimated across the FCGR locus and a model-free analysis was performed to determine association with RA. This was followed by regression analysis, allowing for phase uncertainty, to identify the particular haplotype(s) that influences disease risk. Our results reveal that FCGR2A, FCGR2B and FCGR3B were not associated with RA. The haplotype with the strongest association with RA susceptibility was the FCGR3A–FCGR3B 158V-NA2 haplotype (odds ratio 3.18, 95% confidence interval 1.13–8.92 [P = 0.03] for homozygotes compared with all genotypes). The association was stronger in the presence of nodules (odds ratio 5.03, 95% confidence interval 1.44–17.56; P = 0.01). This haplotype was also more common in North Indian/Pakistani RA patients than in control individuals, but not significantly so. Logistic regression analyses suggested that FCGR3A remained the most significant gene at this locus. The increased association with an FCGR3A–FCGR3B haplotype suggests that other polymorphic variants within FCGR3A or FCGR3B, or in linkage disequilibrium with this haplotype, may additionally contribute to disease pathogenesis.

An unusual form of autoimmune hepatitis in young Somalian men

BACKGROUND

Significant diversity in disease severity has been identified for autoimmune disorders among different ethnic groups. Current knowledge of both the natural history and management of autoimmune hepatitis (AIH) has been derived from European or Japanese patients, and there is limited information about the disease in patients from other ethnic groups.

AIMS

To assess the clinical, histological and immunological features of AIH in patients from Somalia and to determine their response to therapy.

METHODS

Retrospective review of a cohort of young Somalian men with atypical AIH compared with a control group of European patients.

RESULTS

The six Somalian men were younger at presentation (median age 37 (range 24-59) years) than the seven female and three male European controls (55 (34-54) years, P = 0.06). The Somalians had slightly more severe disease at presentation-median modified Ishak stage of 2.5 compared with 2 in Europeans (P = 0.61) and four (66%) had features of cholestasis compared with only one (10%) European patient (P = 0.04). Therapy with prednisolone and azathioprine was completely effective for eight of 10 Europeans but only one of seven Somalians (P = 0.04). Analysis of human leucocyte antigen types revealed differences between the Somalian and European patients, although these differences did not reach statistical significance.

CONCLUSIONS

Somalian men with AIH present with cholestatic features and respond poorly to standard immunosuppressive regimes.

Issues in cross-cultural validity: example from the adaptation, reliability, and validity testing of a Turkish version of the Stanford Health Assessment Questionnaire

OBJECTIVE

Guidelines have been established for cross-cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ).

METHODS

Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross-cultural validity is tested through DIF by comparison with data from the UK version of the HAQ.

RESULTS

The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (alpha = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item.

CONCLUSIONS

Cross-cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.

Characteristics of autoimmune hepatitis in patients who are not of European Caucasoid ethnic origin

BACKGROUND

Significant diversity in disease severity has been identified for autoimmune disorders among different ethnic groups but there is a lack of data on autoimmune hepatitis (AIH) in populations other than those of European Caucasoid (EC) or Japanese extraction.

AIMS

To assess the clinical features, response to therapy, and eventual outcome in AIH patients of non-EC ethnicity.

METHODS

A retrospective review of a regularly updated database of patients with AIH referred to liver outpatient clinics at King's College Hospital, London, since 1983.

RESULTS

Twelve patients were identified (10 female; six African, five Asian, one Arabic; median age at presentation 30 years (range 12-58)) who satisfied international criteria for type 1 (11 cases) or type 2 (one case) AIH. Nine (75%) had cholestatic serum biochemistry and three (25%) had mild biliary changes on liver biopsy without definitive features of primary biliary cirrhosis or cholangiographic evidence of primary sclerosing cholangitis. Four showed a complete biochemical response to standard prednisolone with or without azathioprine therapy, three partial, and five no response. Four have required liver transplantation for intractable disease. By comparison with 180 EC patients with definite AIH attending during the same period, the non-EC patients were younger (p<0.05), presented with cholestatic biochemistry (p=0.014), and morphological biliary features more frequently (p<0.0005) and showed a poorer initial response to standard therapy (p<0.0005).

CONCLUSIONS

Clinical expression of AIH in non-EC patients seems to differ in important respects from that in EC or Japanese patients. Management of such patients is challenging and may require alternative or more aggressive treatment strategies.

Genetic studies, clinical heterogeneity, and disease outcome studies in rheumatoid arthritis

HLA haplotypes influence various clinical RA features considered to reflect severity in case-control and cohort studies. Of particular note is the fact that HLA generally influences the development of erosive and sometimes seropositive and nodular disease; in prospective studies, it noticeably affects joint surgical intervention. These are valuable clues indicating that HLA influences RA severity and chronicity. Nevertheless, HLA influences are generally weak enough so as to require large study subject numbers for detection. As a result, HLA genotyping has restricted usefulness for prediction of clinical severity in individual patients.

Does the shared epitope genotype influence either the susceptibility to or the phenotype of corneal melting?

PURPOSE

To investigate the role of the shared epitope alleles in determining susceptibility to and the phenotype of corneal melting in patients with rheumatoid arthritis (RA).

METHODS

The HLA class 1 and 2 genotype was determined for 17 patients with rheumatoid-associated comeal melting by the phototyping method. HLA-DR4 subtyping was performed by PCR sequence-based typing. The frequency of all the shared epitope alleles and, in particular, of the higher-risk *0401 and *0404 alleles, was compared with healthy controls and unrelated RA patients, with and without extra-articular manifestations. A comparison was also made between the shared epitope genotype of the corneal melt patients and local, ocular disease characteristics.

RESULTS

Thirteen (76%) patients with corneal melt possessed at least one shared epitope allele and 5 (29%) possessed two alleles. The dominant alleles were variants of the DR4 family, notably the *0401, *0404 and *0408 alleles. Both the allele frequency and a double dose of shared epitope alleles were more common in the three RA patient groups than in the healthy, control group (p < 0.005). Although the frequency of the higher-risk alleles was similar in the three RA patient group, a trend existed for a double dose of higher-risk alleles to be more common in the patients with either corneal melt or other extra-articular manifestations (p > 0.2). No association was found between the number or type of shared epitope alleles and any of the ocular disease characteristics studied.

CONCLUSIONS

The results of this study suggest that the shared epitope alleles do not influence the ocular disease phenotype of corneal melt in RA patients. Shared epitope determination of RA patients may help to identify those susceptible to either corneal melt or other extra-articular disease. RA patients with a double dose of higher-risk alleles may have an increased risk of corneal melt.

Approaches to rheumatoid arthritis in 2000

The year 2000 was characterized by euphoria among clinicians based on the continued and consolidated success of tumor necrosis factor (TNF) inhibition but also by problems caused by the high cost of this therapy. Looking at the risks and adverse effects has only begun, and there is so far a remarkable lack of publications dealing with this topic. Leflunomide also emerges as an established disease-modifying antirheumatic drug (DMARD). Other therapies include the cyclooxygenase-2 (Cox-2) inhibitors, which are tolerated better by the gastrointestinal system but raise concerns regarding thromboembolism in patients at risk. The enthusiasm regarding Cox-2 inhibitors is somewhat tempered by recent reports of thromboembolic complications, although those have been rare. The advances in research regarding mechanisms of inflammation and pathogenesis continue to generate new therapeutic approaches, which, however, remain mostly experimental. The complexity of genetics has been emphasized by reports on susceptibility and severity relation to TNF, mannose-binding lectin, and gamma-interferon polymorphism. Epidemiologic studies focusing on prevalence, incidence and outcome continue to deliver conflicting messages. One major worry relates to chronic inflammation in RA and other rheumatic diseases as putative cause of accelerated atherosclerosis.

Fcgamma receptor type IIIA is associated with rheumatoid arthritis in two distinct ethnic groups

OBJECTIVE

To investigate a possible association between a functional polymorphism in the intermediate-affinity receptor for IgG called Fc-gamma receptor type IIIA (FcgammaRIIIA [CD16]) and rheumatoid arthritis (RA).

METHODS

This was an allelic association study in which a single nucleotide polymorphism in FcgammaRIIIA was examined as a susceptibility and/or severity factor for RA. The FcgammaRIIIA-158V/F polymorphism was genotyped by direct sequencing in 2 well-characterized ethnic groups, UK Caucasians (141 RA patients and 124 controls) and North Indians and Pakistanis (108 RA patients and 113 controls).

RESULTS

The FcgammaRIIIA-158V/F polymorphism was associated with RA in both ethnic groups (P = 0.028 for UK Caucasians, P = 0.050 for North Indians and Pakistanis, and P = 0.003 for both groups combined). FcgammaRIIIA-158VF and -158W individuals had an increased risk of developing RA in both populations (UK Caucasians odds ratio [OR] 1.6, P = 0.050; North Indians and Pakistanis OR 1.9, P = 0.023; and combined groups OR 1.7, P = 0.003). In the UK Caucasian group, the highest risk was for nodular RA, a more severe disease subset, associated with homozygosity for the FcgammaRIIIA-158V allele (OR 4.4, P = 0.004). There was also evidence for an interaction between the RA-associated HLA-DRB1 allele and the presence of at least 1 FcgammaRIIIA-158V allele in predicting susceptibility to RA (OR 5.5, P = 0.000).

CONCLUSION

We have demonstrated that the FcgammaRIIIA-158V/F polymorphism is a susceptibility and/or severity marker for RA in 2 distinct ethnic groups. This finding may ultimately provide additional insights into the pathogenesis of RA and other autoantibody/immune complex-driven autoimmune diseases.