Primary Sjögren's syndrome

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disorder characterized by focal lymphocytic infiltration of the exocrine glands causing dry eyes and dry mouth. Similar glandular features can also occur as a late complication in patients with other rheumatic disorders, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and scleroderma ('secondary' Sjögren's syndrome).¹ Anti-Ro and/or anti-La (ENA) antibodies are found in approximately 70% of pSS patients, generally with ANA positivity. Hypergammaglobulinaemia is also common. Systemic features also occur in some patients with pSS. A positive rheumatoid factor (RF) is often seen and so if patients present with arthritis, dryness and a positive RF a diagnosis of pSS should be considered as a possible alternative to RA. Anti-CCP antibodies are more specific for RA.

Postviral Syndrome-How can a Diagnosis be Made? A Study of Patients Undergoing a Monospot Test

Eighty-nine of 150 patients having a Monospot test filled out a questionnaire about their illness, and the General Health Questionnaire. They completed a follow-up questionnaire 6 months later. Twelve (8%) had a positive Monospot. Twenty-eight of 83 serum samples tested (34%) were positive for VP1 enteroviral antigen. Forty of the patients had a self limiting illness, 13 had a definite diagnosis (excepting glandular fever), 14 had a possible postviral syndrome, 10 had recurrent sore throats/flu, and 12 had a chronic non-specific illness. Patients with a specific diagnosis were less likely to complain of aching muscles/joints, sore throat, tiredness or loss of concentration. Their GHQ scores were lower, although this just failed to reach significance (P=0.08), and they scored significantly lower on the somatic symptoms subscale (P=0.022). Overall 72% scored above the GHQ threshold for ‘psychological caseness’ which is higher than in other studies. Sixty-five per cent of the sample questioned at 6 months felt that their illness started with a viral infection. The methodological problems involved in making a diagnosis of postviral syndrome are discussed.

Daytime patterning of fatigue and its associations with the previous night's discomfort and poor sleep among women with primary Sjögren's syndrome or rheumatoid arthritis

OBJECTIVES

Fatigue is a prominent symptom in many rheumatic diseases and has a substantial impact on many outcomes. In previous research, fatigue has been linked with poor sleep and discomfort, including joint pain and sicca symptoms. The aim of the present study was to investigate prospectively the daily variations in fatigue and the roles of discomfort and adequacy of sleep the previous night in that fatigue for people with primary Sjögren's syndrome (pSS) or rheumatoid arthritis (RA).

METHODS

Thirty-nine women with pSS or RA reported their discomfort and fatigue for 35 days using the Profile of Fatigue and Discomfort. Sleep was monitored with wrist actigraphy, and the quantity and quality of the night's sleep was reported in a diary each morning.

RESULTS

The pattern of fatigue did not differ significantly between women with pSS and women with RA. For participants with either condition, both somatic and mental fatigue increased steadily throughout the day. Multi-level regressions indicated that evenings of worse discomfort were followed by poorer reported quantity/quality of sleep and worse sleep efficiency (percentage of time asleep when in bed). In addition, a night of worse discomfort and poor sleep was followed by more severe fatigue compared with the individual's average.

CONCLUSIONS

Fatigue management for people with rheumatic disease could include strategies for coping with discomfort at night and difficulties in sleeping. Further research into ameliorating fatigue should include assessments of persistent discomfort or periods of insomnia and identify disease-specific needs that require targeted intervention.

Estimating the prevalence among Caucasian women of primary Sjögren's syndrome in two general practices in Birmingham, UK

OBJECTIVE

To establish the prevalence among women of primary Sjögren's syndrome (PSS) in Birmingham, UK.

METHODS

Eight hundred and forty-six female Caucasians from two general practitioner lists were invited to complete a questionnaire that included a screening question on dry eyes and mouth. Individuals who responded positively were evaluated further.

RESULTS

Overall, 65/% of individuals who were sent a questionnaire responded. Two had possible PSS, but were negative for anti-Ro/La antibodies. Our estimates of the prevalence of PSS ranged from < 0.1% up to 0.4%, depending on the assumptions used.

CONCLUSION

Our data support previous studies suggesting a prevalence of PSS in the community of 0.1-0.6% rather than those suggesting a higher figure.

Patient-reported outcomes in primary Sjogren's syndrome: comparison of the long and short versions of the Profile of Fatigue and Discomfort--Sicca Symptoms Inventory

OBJECTIVES

The long-form 64-item Profile of Fatigue and Discomfort--Sicca Symptoms Inventory (PROFAD-SSI) questionnaire was developed as a patient-reported assessment tool for use in primary SS (PSS) and other rheumatic disorders. In this study, we assess whether the (shorter and more practical) 19-item PROFAD-SSI-SF (short form) gives similar results and whether a still briefer version using visual analogue scales (VASs) is feasible.

METHODS

Questionnaire surveys comprising the long and short versions of the PROFAD-SSI were mailed to 43 patients with PSS and 50 patients with RA, who were asked to complete these contemporaneously as well as repeating the process 1 month later. PSS patients also completed a series of VASs comprising fatigue and sicca domains of the SSI.

RESULTS

Surveys were returned from 35 PSS patients and 35 RA patients. All domains of the long- and short-form PROFAD-SSI showed strong correlations (Spearman rho between 0.779 and 0.996, P < 0.01). Factor analysis generally confirmed the previously validated domain structure with Cronbach's alpha = 0.99. The PROFAD-SF somatic fatigue domain correlated more strongly with a fatigue VAS than did the mental fatigue domain. The SSI-SF domain scores correlated with equivalent VAS scores.

CONCLUSION

The long- and short-form PROFAD-SSI questionnaires correlate closely suggesting that the PROFAD-SF is valid as an outcome tool. Preliminary data also suggest that an even briefer form with compression of the domains into single VAS is also feasible.

The Sjögren's Syndrome Damage Index--a damage index for use in clinical trials and observational studies in primary Sjögren's syndrome

OBJECTIVE

To validate a tool for assessment of accumulated damage in patients with Primary SS (PSS).

METHODS

Of the total 114 patients fulfilling American-European Consensus Group (AECG) criteria for PSS 104 were included in the study and assessed by rheumatologists at T (time) = 0 months and T = 12 months. On each occasion, damage and activity data, and autoantibody status were collected. SF-36 and Profile of Fatigue and Discomfort-Sicca Symptoms Inventory (PROFAD-SSI) questionnaires were completed. Cross-sectional analysis of this data was subject to a process of expert validation by 11 ophthalmologists, 14 oral medicine specialists and 8 rheumatologists. Items were removed from the index if >or= 50% of respondents recommended exclusion. Statistical validation was performed on remaining items. Spearman's rank analysis was used to investigate associations between damage scores and other disease status measures and Wilcoxon matched-pair analysis to assess sensitivity to change in the damage score.

RESULTS

Based on the expert validation, a 29-item damage score was agreed incorporating ocular, oral and systemic domains. Total damage score correlated with disease duration at study entry (r = 0.436; P < 0.001), physical function as measured by SF-36 (r = 0.250, T = 0 months; r = 0.261 T = 12 months) and activity as measured by the Sjögren's Systemic Clinical Activity Index (r = 0.213, T = 0 months; r = 0.215, T =12 months). Ocular damage score correlated with the 'eye dry' domain of PROFAD-SSI (r = 0.228, T = 0 months; r = 0.365, T = 12 months). Other associations not present on both assessments were considered clinically insignificant. On Wilcoxon analysis, the index was sensitive to change over 12 months (z = -3.262; P < 0.01).

CONCLUSION

This study begins validation of a tool for collection of longitudinal damage data in PSS. We recommend further trial in both the experimental and clinical environment.

Measuring fatigue among women with Sjögren's syndrome or rheumatoid arthritis: a comparison of the Profile of Fatigue (ProF) and the Multidimensional Fatigue Inventory (MFI)

BACKGROUND

Fatigue is common in both Sjögren's syndrome (SS) and rheumatoid arthritis (RA) and can restrict functioning.

AIMS

We tested the convergent validity of the Profile of Fatigue (ProF) using the Multidimensional Fatigue Inventory (MFI) in SS and RA.

METHODS

The 16-item ProF and the 20-item MFI were completed by 82 White-British women aged 35-79 years (mean 60.4 years). Thirty-four had been diagnosed with SS for a mean of 7.0 years and 48 had been diagnosed with RA for a mean of 14.5 years. The ProF measures four somatic facets of fatigue and two mental facets; the MFI contains one mental and four somatic facets. The structures of the items from both measures were tested by principal component factor analysis using varimax rotation.

RESULTS

No significant differences in fatigue were found between the women with SS or RA. Five factors explained a total of 76% of the variance of the MFI; six factors explained 94% of the variance of the ProF. Mental fatigue items from both questionnaires loaded onto separate factors from somatic fatigue items; the two original facets of mental fatigue in the ProF were replicated. The four somatic fatigue facets of the ProF were generally replicated but the somatic facets of the MFI did not replicate as clearly. Equivalent facets correlated well between the two questionnaires (r >or= 0.65).

CONCLUSIONS

Both the ProF and the MFI distinguish between somatic and mental fatigue in SS and RA but the ProF appears better at resolving somatic facets of fatigue.

Reduction of fatigue in Sjögren syndrome with rituximab: results of a randomised, double-blind, placebo-controlled pilot study

OBJECTIVE

Primary Sjögren syndrome (pSS) causes significant systemic symptoms including fatigue as well as glandular dysfunction. There are currently no effective systemic therapies; however, open label series have suggested that rituximab may be beneficial for systemic and glandular manifestations. Therefore, we performed a double blind, placebo-controlled, randomised pilot study of the efficacy of rituximab in reducing fatigue in pSS.

METHODS

A total of 17 patients with pSS and a score on fatigue visual analogue scale (VAS) >50 were randomised to receive either 2 infusions of rituximab 1 g or placebo; patients also received oral and intravenous steroids. Outcome measures included: the proportion of patients with >20% reduction in fatigue VAS, changes in pSS related symptoms, health related quality of life and immunological parameters of pSS. These were measured 6 months after therapy.

RESULTS

There was significant improvement from baseline in fatigue VAS in the rituximab group (p<0.001) in contrast to the placebo group (p = 0.147). There was a significant difference between the groups at 6 months in the social functioning score of SF-36 (p = 0.01) and a trend to significant difference in the mental health domain score of SF-36 (p = 0.06). There was one episode of serum sickness in the rituximab treated group.

CONCLUSIONS

This is the first double blind study of rituximab in pSS to show benefit; further studies are justified.