According to a recent study published in the British Medical Journal Open Respiratory Research, D12 scores have reliable measuring qualities in RA-ILD. It enables the determination of the severity of dyspnea as described by its physical and affective components in patients with interstitial lung disease due to rheumatoid arthritis (RA-ILD).
Dr. Swigris and colleagues analyzed the data from the TRAIL 1 study, in which 123 individuals with RA-ILD were randomly assigned to receive either pirfenidone or a placebo for 52 weeks to evaluate the measuring capabilities of D12. The study findings showed that the D12 measurement properties were highly consistent (α=0.95, 0.95, 0.95, 0.95, and 0.96 at various stages) and reliable (test-retest reliability of 0.85). The majority of hypotheses (93%) related to D12 were confirmed, demonstrating its validity. Known-group validity was established through significant differences between subgroups of patients based on dyspnea and physiological impairment levels. Longitudinal validity was also supported through associations between D12 and anchor scores over time. D12 scores were found to be responsive to changes in dyspnea over time, with a minimal within-patient change threshold of 3 points for worsening.
RA-ILD is a condition affecting a significant number of RA patients, leading to symptoms that substantially diminish their quality of life and raise concerns about survival. Dyspnea, or difficulty breathing, is the most common respiratory symptom in RA-ILD and significantly affects patients’ well-being. The D12 questionnaire is a valuable tool for evaluating both the physical and emotional aspects of dyspnea. Early assessment and management of dyspnea using tools like the D12 questionnaire are crucial for improving the lives of individuals with RA-ILD. However, further research is recommended to ensure the validity of the D12 scores in this population.
Reference
Swigris JJ, Danoff S, Dellaripa PF, Doyle TJ, Solomon JJ. Reliability and responsiveness of the D12 and validity of its scores as a measure of dyspnoea severity in patients with rheumatoid arthritis-related interstitial lung disease. BMJ Open Respir Res. 2023 Sep;10(1):e001872.