Objective: Determine healthcare resource utilization (HCRU) and costs associated with fatigue and stiffness among patients with rheumatoid arthritis (RA).Methods: A retrospective claims analysis compared RA patients with fatigue or stiffness to matched RA control patients with neither. Claims from a large US commercial insurance database identified new cases of stiffness/fatigue among newly diagnosed patients. Study patients had ≥2 medical claims for RA ≥45 days apart, continuous insurance coverage ≥12 months before RA index (baseline period) and ≥12 months after fatigue/stiffness index (follow-up period). Controls had no diagnosis of fatigue or stiffness ≥12 months before index. Cases had ≥1 claim of fatigue/stiffness after RA index; the first such claim was the index date. Multivariate logistic regressions, adjusting for baseline demographics, comorbidities, medication use and HCRU, were used to predict the propensity of having a fatigue/stiffness diagnosis. Controls were propensity-score matched to cases. Generalized linear models estimated all-cause and RA-specific costs associated with resource use as well as prescription drugs, adjusting for any unbalanced covariates after propensity-score matching.Results: Approximately 32% of newly diagnosed RA patients suffer from fatigue/stiffness. Matched cohorts were analyzed: fatigue vs. control; stiffness vs. control; fatigue and stiffness vs. control. After RA diagnosis, hospitalizations increased: 83% for fatigue, 117% for stiffness and 148% for both; total office visits increased 63%, 113% and 135%, respectively. Greater HCRU yielded significantly greater (all p < .001) per-patient-per-year hospitalization costs vs. matched controls: fatigue ($2554 vs. $1293); stiffness ($2792 vs. $892); fatigue and stiffness ($3322 vs. $1033). Per-patient-per-year costs of office visits increased significantly (all p < .001) vs. matched controls: fatigue ($1373 vs. $908); stiffness ($1580 vs. $761); fatigue and stiffness ($1989 vs. $921).Conclusions: RA patients with fatigue and/or stiffness report more HCRU and incur significantly higher medical costs than RA patients without them.
Keywords: Rheumatoid arthritis; health care resource utilization; health related quality of life; retrospective claims analysis.