Use of the Systemic Lupus International Collaborating Clinics Frailty Index (SLICC-FI) is associated with damage accrual in a multiethnic, cohort of patients with systemic lupus erythematosus (SLE), according to study results published in Arthritis Care & Research (Hoboken).
Researchers aimed to determine the link between SLICC-FI and damage accrual among patients with SLE.
In the current study, damage was determined using the SLICC/American College of Rheumatology (ACR) damage index (SDI) at the last visit (range, 0-51). The initial visit at which the SLICC-FI could be derived was considered the baseline (range, 0-1).
Performance of univariable and multivariable negative binomial regression models was used to establish the association between the baseline SLICC-FI (per 0.05 increase) and change in the SDI (ie, difference between last and baseline SDI), which was adjusted for age at diagnosis, sex, ethnicity, type of insurance, daily prednisolone dose, and use of antimalarial and immunosuppressive drugs at baseline. The multivariable model included age and sex; the other variables were included if a P value of less than .10 were achieved in the univariable models.
A total of 503 patients from the Lupus in Minorities: Nature versus Nurture (LUMINA) cohort were included in the analysis. The mean patient age was 37.1±12.5 years at diagnosis of SLE. Overall, 454 (90.3%) of the patients were women; 174 were Black, 144 were White, 86 were Hispanic from Texas, and 99 were Hispanic from Puerto Rico.
Results of the study showed that the mean SLICC-FI was 0.26±0.06, with 80.9% (n=407503) of the participants being classified as “frail.” The range was 0.09 to 0.49; the submaximal limit was 0.42. The mean baseline SDI was 0.6±1.0; the mean change in SDI score was 1.9±2.2. The mean length of follow-up was 5.2±3.3 years.
Higher SLICC-FI scores at baseline were associated with a significantly greater increase in damage in the univariable analysis (incidence rate ratio [IRR], 1.29; 95% CI, 1.16-1.43; P <.0001). Following adjustment for possible confounders, SLICC-FI remained associated with a significant change in damage accrual in the multivariable model (IRR, 1.20; 95% CI, 1.08-1.33; P =.0015).
In the sensitivity analysis, which included 305 patients with a baseline SDI of 0, the SLICC-FI was associated with a greater change in the SDI in both the univariable model and the multivariable model; however, the association was not significant in the multivariable model.
A major limitation of the current study was the fact that all the 48 original SLICC-FI health deficits related to disease activity, damage, comorbidities, and health-related quality of life could not be included; a total of 44 items were included. Further, it is possible that other confounders might have had an impact on damage accrual.
The researchers concluded, “The SLICC-FI is associated with damage accrual in SLE patients from a multiethnic cohort, supporting the importance of this index in the evaluation of patients [with SLE], combining several aspects of their disease.” They added, “Further analyses in other cohorts and evaluating other outcomes are warranted to fully validate this index.”
Ugarte-Gil MF, Dubey J, McGwin G Jr, Reveille JD, Vilá LM, Alarcón GS. The Systemic Lupus International Collaborating Clinics Frailty Index (SLICC-FI) is associated with damage in systemic lupus erythematosus patients. Arthritis Care Res (Hoboken). Published online March 7, 2022. doi:10.1002/acr.2487