title: Changes in utilization and costs for patients with rheumatoid arthritis, 1997 to 2006.
abstract: BACKGROUND
  Rheumatoid arthritis (RA) is a chronic autoimmune disease that often results in joint pain, inflammation and bone erosions. Perhaps the most notable change in RA treatment during the last decade is the advent of biologics, and, in particular, anti-tumour necrosis factor agents. Given these advances, it is useful to assess how healthcare and work-loss costs of patients with RA have changed.
  
  
  OBJECTIVE
  Our objective was to assess changes in healthcare utilization and costs from 1997 to 2006 for patients diagnosed with RA.
  
  
  METHODS
  Two cohorts (1997 and 2006) of patients with RA and matched controls were identified from two administrative claims databases along with subsamples of employed patients and matched controls. The analysis focused on the more homogeneous employee subsample. We compared annual excess co-morbidity rates, resource utilization and healthcare and work-loss costs per patient between the 1997 (n = 279) and 2006 cohorts (n = 837) with difference-in-differences methodology. Results with p < 0.05 were considered statistically significant.
  
  
  RESULTS
  In the employee subsample, there were no statistically significant differences in the excess prevalence of non-RA co-morbidities or Charlson Co-morbidity Index results, except for cardiovascular disease, which decreased by 11.1%. Excess number of ED visits and days hospitalized decreased by 1.1 visits/patient and 0.9 days/patient, respectively, while rheumatologist visits increased by 0.9 visits/patient. Excess per-patient direct costs were unchanged. However, drug costs increased by $US633/patient, but medical costs decreased by $US618/patient (not significant) [year 2006 values].
  
  
  CONCLUSIONS
  For employed patients with RA, there were significant reductions in per-patient excess hospital days, as well as ED visits, and no changes in excess total direct costs over time. New treatments introduced during the study period may be associated with cost savings that offset changes in employee utilization of drug and medical services. In addition, the reductions in excess ED visits and hospital days suggest improvements in patient quality of life.
authors.affiliation: Analysis Group Inc., Boston, MA, USA. hbirnbaum@analysisgroup.com
authors.forename: Howard G
authors.initials: HG
authors.lastname: Birnbaum
authors.forename: Crystal
authors.initials: C
authors.lastname: Pike
authors.forename: Ritesh
authors.initials: R
authors.lastname: Banerjee
authors.forename: Tracy
authors.initials: T
authors.lastname: Waldman
authors.forename: Mary
authors.initials: M
authors.lastname: Cifaldi
mesh_terms: D000041:Absenteeism; D000328:Adult; D018501:Antirheumatic Agents / Q000191:economics / Q000494:pharmacology / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000191:economics* / Q000628:therapy; D016022:Case-Control Studies; D015331:Cohort Studies; D017281:Cost of Illness; D016208:Databases, Factual / Q000706:statistics & numerical data; D016527:Drug Costs; D004636:Emergency Service, Hospital / Q000191:economics / Q000706:statistics & numerical data / Q000639:trends; D004651:Employment / Q000191:economics / Q000706:statistics & numerical data; D017048:Health Care Costs / Q000639:trends*; D006296:Health Services / Q000191:economics* / Q000706:statistics & numerical data / Q000639:trends; D006760:Hospitalization / Q000191:economics / Q000706:statistics & numerical data / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D013997:Time Factors
chemical_list: D018501:Antirheumatic Agents