Joint inflammation, health-related quality of life linked in an SSc Study

​by Patricia Inácio, PhD | March 12, 2024

Inflammatory arthritis — a condition marked by joint inflammation that causes swelling, pain, and damage — affects about one-third of people with scleroderma, also known as systemic sclerosis (SSc), and is associated with worse health-related quality of life, or HRQoL for short, according to a new study from Australia.

“Our results reveal the significant impact that [inflammatory arthritis] has on patients, with the presence of [such inflammation] being negatively associated with employment, physical function, and HRQoL,” the researchers wrote.

Given that such arthritis is treatable, “further research is needed to understand the extent of joint involvement in SSc and optimal strategies for its management,” the researchers wrote.
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Their study, “Inflammatory Arthritis in Systemic Sclerosis: Its Epidemiology, Associations, and Morbidity,” was published in the journal Arthritis Care & Research.

Synovitis, or joint inflammation, define inflammatory arthritis in study
Inflammatory arthritis is a commonly co-occurring condition in people with scleroderma. While it can lead to disability and represents a psychosocial and economic burden, the true prevalence of inflammatory arthritis in people with SSc remains poorly known.

To shed light on this, an international team led by researchers in Australia analyzed data from 1,717 SSc patients enrolled in the Australian Scleroderma Cohort Study.

A third of the participants (33.3%) experienced inflammatory arthritis over a median follow-up of 4.3 years. Inflammatory arthritis was defined by synovitis — inflammation in the synovial membrane of the joint in one or more joints — as assessed by a physician.

The median age among patients at the onset of inflammatory arthritis was 59.5 years. The percentage of patients with diffuse cutaneous SSc (dcSSc) was significantly higher in this group than in participants without inflammatory arthritis (30.1% vs. 22.7%).

Also, patients with inflammatory arthritis were more likely to experience musculoskeletal manifestations, such as joint contractures (50.1% vs. 36.3%) and/or tendon friction rubs (12.3% vs. 8%), myositis, or inflammation of the muscles (11.2% vs. 5.3%), and sicca symptoms — dry eyes and/or dry mouth (86.5% vs 79.3%). A contracture is the inability to move a joint through its full range of motion, and occurs when muscles, tendons, or other tissues tighten or shorten.

Patients with pulmonary arterial hypertension were less likely to develop inflammatory arthritis.

Patients’ health-related life quality lower than those without SSc
The likelihood of having inflammatory arthritis was significantly associated with being positive for several autoantibodies, which are the self-targeting antibodies that drive SSc. These included antitopoisomerase-1, RNA Polymerase III, and anti-cyclic citrullinated peptide. The opposite was found for anticentromere antibodies.

Elevated markers of inflammation, namely C-reactive protein and erythrocyte sedimentation rate, also were associated with inflammatory arthritis.

Moreover, these patients had a higher risk for having an overlap clinical presentation with rheumatoid arthritis, meaning they had symptoms of both conditions upon examination. They also were more likely to undergo treatment with disease modifying anti-rheumatic drugs, known as DMARDs.
Prednisolone (61.9%), methotrexate (46%) and hydroxychloroquine (44.9%) were the most commonly prescribed medications, followed by leflunomide (4.2%) and mycophenolate mofetil (18.5%).

After adjusting for age and sex, a statistical analysis revealed that dcSSc, and the presence of musculoskeletal manifestations, myositis, and sicca symptoms correlated with the risk of having inflammatory arthritis. C-reactive protein also showed a significant correlation with inflammatory arthritis in a subsequent analysis.

SSc patients’ health-related quality of life was lower compared with age- and sex-matched people without the disease. The presence of inflammatory arthritis contributed to significantly worse health-related quality of life, affecting both physical and mental domains, according to patient-reported outcome measures.

Participants with inflammatory arthritis reported a higher frequency of pain, sleep disturbance, fatigue, anxiety, and depression than those without inflammatory arthritis. Unemployment was also more common in this group.

​Overall, “the presence of [inflammatory arthritis] as a clinical indicator of a more severe phenotype [presentation] in SSc warrants further consideration,” the scientists concluded.