Objective: To evaluate the Systemic Lupus International Collaborating Clinics Frailty Index (SLICC-FI) as a predictor of damage accrual in a primarily Mestizo SLE patient cohort.
Methods: Patients from a single-center prevalent cohort were included. Damage accrual was defined as the increase in the SLICC/American College of Rheumatology (ACR) damage index (SDI) scores between the baseline and the last visits. The SLICC-FI was measured at baseline. Univariable and multivariable Cox regression models were performed to determine the association between the baseline SLICC-FI (per 0.05 increase) and the increase in the SDI, adjusted for possible confounders. Alternative analyses using negative binomial regression models including the difference between the last and the first SDI as outcome were performed.
Results: Of the 265 patients included, 248 (93.6%) were female with mean (SD) age of 35.1 (13.6) years at diagnosis. At baseline, mean (SD) SLE disease duration was 7.3 (6.5) years, SDI was 1.0 (1.2) and the SLICC-FI was 0.22 (0.05). After a mean (SD) of 5.2 (2.2) years of follow-up, the SDI increased in 126 (47.5%) patients, and the final mean (SD) SDI score was 1.7 (1.7). Higher SLICC-FI scores at baseline predicted greater damage accrual in the univariable analysis [Hazard Ratio (HR) =1.38, (CI95% 1.16-1.65); p < 0.001] and in the multivariable model, after adjustment for possible confounders [HR = 1.30 (CI95% 1.02-1.66); p = 0.033].
Conclusion: SLICC-FI predicts the occurrence of damage accrual in a prevalent SLE Latin-American cohort with short or long disease duration, supporting the relevance of this index in the evaluation of SLE patients.
Keywords: damage; frailty; systemic erythematosus lupus; systemic lupus international collaborating clinics frailty index.