Frailty in older adults with systemic lupus erythematosus and emergency department utilization: an administrative claims data analysis of Medicare beneficiaries

Introduction / objectives While presence of concomitant SLE and frailty has been associated with greater emergency department (ED) use than SLE alone in young/mid-aged adults, whether frailty increases ED use in older adults with SLE remains unknown. In a nationally representative United States administrative claims dataset, we investigated the association of frailty duration with use of ED services in the SLE population compared with individuals without systemic rheumatic disease (SRD). Method We identified Medicare beneficiaries >= 65 years with SLE and matched them (1:4) by age and gender with non-SRD comparators with osteoarthritis. Frailty was determined using a claims-based index and examined each study year (1/2006-9/2015). We used mixed-effect Poisson regression to ascertain the effect of frailty duration exposure on the risk of ED visits in those with SLE and in non-SRD participants, adjusting for covariates. Results At baseline (2006), frailty prevalence was similar in participants with SLE (N = 1338; 43.7%) and no SRD (N = 5352; 42.4%) (p = 0.37). Frailty prevalence significantly increased and diverged over time between participants with SLE versus no SRD (67.6% versus 63.7% in 2010 and 83.5% versus 78.1% in 2014) (p < 0.05). As frailty duration increased, risk of ED visits increased in both groups, including after covariate adjustment (SLE: incidence rate ratio [IRR] 1.10, 95% confidence interval [CI] 1.09-1.12; non-SRD: IRR 1.09, 95% CI 1.08-1.10). Conclusions In this cohort of older adults, duration of frailty conferred similar increased risk of ED visits among those with and without SLE. This underscores the importance of measuring frailty in older populations with SLE.