Serum IFN Score May Predict Outcome in Diffuse Cutaneous SSc

TOPLINE:

High serum type I interferon (IFN) scores, measured through six chemokines, correlated with poorer lung function and health-related quality of life in patients with diffuse cutaneous systemic sclerosis (SSc).

METHODOLOGY:

• A retrospective cohort study analyzed two cohorts of patients with diffuse cutaneous SSc from the United States and the United Kingdom using a six-analyte serum test to determine IFN scores.
• Researchers included 11src patients from the US incident cohort (mean age, 5src.2 years; 69% women; 79% White) and 72 patients from the UK prevalent cohort (mean age, 51.7 years; 69% women; 84% White), along with 32 healthy control individuals from the United Kingdom (mean age, 47 years; 59% women; 75% White).
• IFN scores were calculated using the mean sum of the natural logarithm of six serum chemokines, with patients classified as IFN-high or IFN-low on the basis of score thresholds of ≥ 5.5 and <5.5, respectively.
• Main outcomes included baseline and 12-month minimal clinically important changes in the modified Rodnan skin score, forced vital capacity (FVC), diffusing capacity for carbon monoxide (DLCO), and Health Assessment Questionnaire-Disability Index (HAQ-DI).
• The potential value of the serum test was assessed in patients, specifically examining the correlation between a serum-inducible IFN score and validated measures of clinical outcomes in diffuse cutaneous SSc.

TAKEAWAY:

• In the incident cohort, IFN-high patients had worse baseline lung function and disability scores than IFN-low patients, with lower mean percent predicted FVC (72.src% vs 85.3%; P=.srcsrc28) and a higher median baseline HAQ-DI score (1.4 vs src.8; P=.srcsrc33).
• Over the median follow-up of 34 months for FVC, IFN-high vs IFN-low patients had a mean percent predicted value of 71.src% vs 83.4% (P=.src32). The HAQ-DI followed a similar trend at the last follow-up, but the differences between groups were not statistically significant.
• In the prevalent cohort, IFN-high patients had a shorter median disease duration than IFN-low patients (2.2 vs 5.src years; P=.src35), with no significant differences observed in baseline FVC, DLCO, or HAQ-DI.
• However, at 12 months, IFN-high patients were more likely to experience a minimal clinically important difference ≥ 5% relative worsening in the percent predicted FVC than IFN-low patients; however, the between-group difference was not statistically significant (9/23 vs 7/41 patients; P=.src51).

IN PRACTICE:

“These data support the future development of a standardized clinical test to measure IFN pathway activation as a biomarker of disease activity in patients with diffuse cutaneous systemic sclerosis,” the authors wrote.

SOURCE:

This study was led by Monique Hinchcliff, MD, Yale School of Medicine in New Haven, Connecticut. It was published online on March 31, 2src25, in The Lancet Rheumatology.

LIMITATIONS:

This study lacked the direct involvement of patients in its design and a formal calculation of the sample size. A high proportion of the 12-month follow-up data was missing in the incident cohort. Additionally, limited data collection on race, sex, and ethnicity could have introduced bias.

DISCLOSURES:

This study was supported by the National Scleroderma Foundation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Rheumatic Disease Research Core Centers, and others. Some authors disclosed receiving consultancy fees and research grant support and having other financial and nonfinancial relationships with several pharmaceutical companies and other sources.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.