Background/Purpose: Rheumatoid arthritis (RA) management paradigms have changed over the last two decades. Evidence now supports aggressive immunosuppression with early use of combination disease modifying anti rheumatic drugs (DMARDs) and biologics when standard DMARDs fail. The use of composite tools to measure disease activity has become standard assessment tools in the clinic with an aim of achieving remission or low disease activity. We set out to study the changing patterns of disease activity and disability in RA over the last 20 years. 

Methods: Retrospective cross-sectional surveys were undertaken at four time points from two secondary care rheumatology departments in London. Patients included had a diagnosis of RA by the 1987 criteria of the American College of Rheumatology. The surveys collected data between (i) 1996-97; (ii) 2001-3; (iii) 2009-10; (iv) 2012-14. Data collected comprised demographic details (age, sex and disease duration), 28 joint disease activity score (DAS28) and its component parts. Disability measures  using the Health Assessment Questionnaire (HAQ) scores were also available for the first, second and fourth cohorts. 

Results: Overall 1324 patients were studied. The groups had similar demographic features (76-80% were female; their mean ages were 58-60 years; and their mean disease durations were 9.1-10 years. Disease activity fell over time, with the proportion of patients in remission significantly increasing from 8% in the earliest cohort to 28% in the most recent. The proportion with severe disease fell from 50% in the earliest cohort to 18% in the most recent, whilst the proportion with moderate disease remained constant (38-42%). Although the number of swollen joints has decreased in each DAS28 group over time, the more objective tender joint counts and patient global scores have increased or remained stable. In contrast, there was no fall in disability levels over time. Mean HAQ scores were 1.30 in 1996-97 and 1.32 in 2012-14, with a slightly higher mean HAQ of 1.52 in 2001-03. Comparing disability change over time across the disease activity groups, mean HAQ scores in patients in remission and low disease activity states increased. The correlation between disease activity and disability became weaker over time; in 1996-97 Spearman’s rho was 0.56, in 2001-03 it was 0.55 and in 2012-14 it was 0.44.

Conclusion: Our data add to the existing evidence base, confirming that the trends towards milder disease are continuing. There is a widening gap between the subjective and objective components of DAS, with climbing tender joint counts in the face of reduced numbers of swollen joints. Other factors such as comorbidity including psychological disease, may be very relevant. Depression and anxiety are highly prevalent in RA. Our data show that the relationship between disease activity and disability has changed over time. Further research is needed to understand how to best manage non-severe RA, that now makes up the largest burden of clinic attenders. Strategies to address comorbidity and mental health needs should to be evaluated.

« Back to 2015 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/has-the-relationship-between-disease-activity-and-disability-in-rheumatoid-arthritis-changed/