RA Impact of Disease Score Useful Across a Range of Rheumatic Diseases

The rheumatoid arthritis impact of disease (RAID) score effectively measured the impact of disease on quality of life across a range of rheumatic diseases and was shown to be feasible for clinical use, according to study results published in RMD Open.

The RAID score is a patient-reported outcome measure for evaluating the impact of rheumatoid arthritis (RA) on a patient’s quality of life. It includes domains of pain, function, fatigue, sleep disturbance, emotional and physical well-being, and coping. Since RAID has successfully been adapted for use in patients with psoriatic arthritis and the questions are largely generic, researchers hypothesized RAID could also apply to other rheumatic diseases. The researchers evaluated the performance of the RAID score in patients with ankylosing spondylitis (AS), polymyalgia rheumatica (PMR), systemic lupus erythematosus (SLE), primary Sjögren syndrome (pSS), idiopathic inflammatory myositis (IIM), and systemic sclerosis (SSc), and compared it with performance in patients with RA.

The German Rheumatology Research Centers’ National Database provided clinical data and patient-reported outcomes. Physician-derived information included the physician global assessment of disease activity. Patients completed questionnaires during visits including the RAID, patient global health status, patient global disease activity, 5-item World Health Organization Well-Being Index (WHO-5), and EuroQol 5 dimensions questionnaire (EQ-5D). Patients were included in the study if they completed a RAID questionnaire between 2015 and 2019.

The researchers calculated age- and sex-adjusted partial correlation coefficients between RAID and each assessment tool for patients with each diagnosis. Mean differences between the RAID score and the other outcomes were compared with the respective differences for RA. Linear regression was used to assess the age- and sex-adjusted effect of each diagnosis on the difference between the RAID score and other scores using RA as the reference.

A total of 12,398 patients were identified with a RAID score. Across all diagnoses, the RAID score correlated most strongly with the patient global health status (r=0.71-0.83). The correlation was moderately strong for patient global disease activity (r=0.59-0.79), WHO-5 (r=0.65-0.81), and EQ-5D (0.68-0.73), and weak for physician global disease activity (r=0.23-0.38).

Mean differences between the RAID composite score and the other patient- or physician-reported outcomes were small for patient global disease activity (0 to -0.6), patient global health (-0.4 to -0.9), WHO-5 (-0.7 to -1.3). The deviation was somewhat larger for EQ-5D (1.1 to 1.7) and physician global disease activity (1.4 to 2.2). However, the discrepancies between the 5 outcomes and the RAID were similar to RA. There were no clinically-relevant effects of any of the diagnoses on the differences between the RAID scores and the other outcomes.

The distributions of the weighted and unweighted RAID composite score for each diagnosis were similar. This suggested the RAID score is feasible for use in the clinical setting.

Limitations of the study included a large proportion (up to 33%) of patients with rheumatic diseases who had missing RAID values, and a lack of patients with certain diagnoses who completed each outcome measurement tool (ie, patients with IIM who completed the WHO-5).

The study authors concluded, “Given the growing popularity of [patient reported outcomes] and the fact that rheumatologists increasingly need to collect them, it is necessary to determine measures which are feasible, reliable and sensitive in the clinical setting. The RAID meets these requirements and can be used to measure the impact of disease for AS, PMR, SLE, pSS, IIM, and SSc as well, if no diagnosis-specific alternative is available.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Thiele K, Albrecht K, Zink A, et al. Is the Rheumatoid Arthritis Impact of Disease (RAID) score a meaningful instrument for other inflammatory rheumatic diseases? A cross-sectional analysis of data from the German National Database. RMD Open. Published online July 6, 2022. doi:10.1136/rmdopen-2022-002342