Study objectives: Sarcoidosis is a granulomatous disorder primarily affecting the lung, but with frequent extrapulmonary organ involvement. There are no comprehensive scoring systems for sarcoidosis disease severity. Our goal was to develop and validate an objective and comprehensive sarcoidosis disease severity scoring system.
Design: Three sarcoidosis experts reviewed clinical data on 104 patients with biopsy-confirmed sarcoidosis. Each expert independently scored disease severity using a visual analog scale. Interrater agreement was assessed. Univariate analysis was performed, and those variables with p values < or = 0.25 were used in backward regression multivariable analysis. A model was obtained including variables with a p value of < or = 0.15 to predict severity scores. This model was subsequently validated using an independent panel of three additional international experts.
Setting: Granuloma clinic at National Jewish Medical and Research Center.
Patients: A total of 104 patients with biopsy-confirmed sarcoidosis.
Interventions: None.
Measurements and results: Pairwise assessment of interrater agreement yielded high degrees of correlation with Spearman correlation coefficients of 0.86 to 0.89 and an intraclass correlation coefficient of 0.87. Univariate analysis showed that smoking status, immunosuppressive therapy, percent predicted for diffusing capacity of the lung for carbon monoxide (Dlco), FEV1, FVC, and total lung capacity, FEV1/FVC ratio, disease duration, sites of organ involvement, and African-American race were associated with mean severity score. The multivariable model included cardiac and neurologic involvement, current therapy with noncorticosteroid immunosuppressive agents, Dlco percent predicted, FEV1/FVC ratio, African-American race, FVC percent predicted, and skin involvement. This model was validated using additional reviewer scores yielding Spearman correlation coefficients of 0.66 to 0.76 and an intraclass correlation coefficient of 0.74.
Conclusions: We derived an objective disease severity scoring system that incorporates data on demographics, pulmonary function, and organ involvement to produce a whole-body sarcoidosis assessment. This preliminary tool has potential applicability in the assessment of disease severity in sarcoidosis research.