Pattern and predictors of the initiation of biologic agents for the treatment of rheumatoid arthritis in the United States: an analysis using a large observational data bank.
OBJECTIVE
The aim of this study was to identify factors associated with the initiation of biologic agents for the treatment of rheumatoid arthritis (RA) in a large US observational cohort.


METHODS
Semiannual patient-reported data in the ARAMIS (Arthritis, Rheumatism and Aging Medical Information System) data bank from January 1998 to January 2006 were analyzed retrospectively using pooled logistic regression (with adjustment for center-level and temporal effects) to identify patient-, disease-, and treatment-related characteristics associated with the initiation of biologics for the treatment of RA.


RESULTS
The analysis included 1545 patients from 7 US centers. By 2006, 41.4% of 679 patients remaining in the sample had received biologics. Initiation of biologics was significantly associated with greater disability in the previous 6-month period (per 1-unit increase in Health Assessment Questionnaire score: odds ratio [OR] = 1.45; 95% CI, 1.22-1.72; P < 0.01) and treatment in the previous period with steroids (OR = 2.24; 95% CI, 1.76-2.85; P < 0.01) or nonbiologic disease-modifying antirheumatic drugs (OR = 2.43; 95% CI, 1.71-3.46; P < 0.01). Two sociodemographic factors were significant predictors of decreased use of biologics: older age (per 10 years: OR = 0.74; 95% CI, 0.660.82; P < 0.01) and lower annual income (per $10,000 reduction: OR = 0.95; 95% CI, 0.91-1.00; P = 0.04). There were no significant differences with respect to sex, race, employment status, comorbidity, previous NSAID use, or treatment center.


CONCLUSIONS
Disease- and treatment-related factors were significant predictors of the initiation of biologics for RA. Independent of these factors, however, biologics were less often used in patients who were older and those with lower incomes. Use of biologics increased steadily over the period studied.
DeWitt
Esi Morgan
EM
Department of Pediatrics, Division of Rheumatology, Duke University Medical Center, Durham, North Carolina, USA.
Lin
Li
L
Glick
Henry A
HA
Anstrom
Kevin J
KJ
Schulman
Kevin A
KA
Reed
Shelby D
SD
D000367:Age Factors; D018501:Antirheumatic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology / Q000627:therapeutic use*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology
D018501:Antirheumatic Agents; D007155:Immunologic Factors