Diagnostic delay in patients with rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis: results from the Danish nationwide DANBIO registry

Abstract

Background/purpose: Early diagnosis of inflammatory rheumatic diseases is important in order to improve long-term outcome. We studied whether delay in diagnosis (time between onset of symptoms and establishment of diagnosis) in patients with rheumatoid arthritis (RA), psoriatic arthritis (PSA) and ankylosing spondylitis (AS) changed from year 2000 to 2011.

Methods: Month and year of initial symptoms and diagnosis, gender, hospital, year of birth and date of first data entry were obtained for 13,721 patients with RA, PSA or AS who had been registered in the DANBIO registry. Time between symptom onset and diagnosis was modelled using generalised linear regression to predict the average duration for each calendar year of initial symptoms with adjustments for gender, year of birth and date of DANBIO entry.

Results: Patients with valid data (RA: 10,416 (73%); PSA: 1970 (68%); AS: 1335 (65%)) did not differ significantly from the whole DANBIO population, except more missing data in early years. The regression model showed that the mean duration from initial symptoms to diagnosis for RA, PSA and AS declined steadily from 30, 53 and 66 months (year 2000), respectively, to 3-4 months (year 2011). Sensitivity analyses including patients who were included after 2005, patients who had received biological treatment or had symptom onset less than 2 and 5 years prior to first entry into DANBIO showed similar results.

Conclusion: Since the year 2000, a significant reduction in diagnostic delay was observed in this large cohort of patients with RA, PSA or AS, probably reflecting a stronger awareness of the importance of early diagnosis.

Keywords: Ankylosing Spondylitis; Epidemiology; Psoriatic Arthritis; Rheumatoid Arthritis.

Figure 1

Number of patients with and without data on years for symptom onset and diagnosis shown by year of entry into DANBIO for patients with rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis.

Figure 2

Time from symptom onset to diagnosis by calendar year of initial symptoms: (A) rheumatoid arthritis, (B) psoriatic arthritis and (C) ankylosing spondylitis.

Figure 3

Impact of year of symptom onset and birth cohort on time from symptom onset to diagnosis: (A) rheumatoid arthritis, (B) psoriatic arthritis and (C) ankylosing spondylitis

Figure 4

Time from symptom onset to diagnosis from the year 2000 to the year 2011 in 10 416 patients with rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis adjusted for gender, birth year and year of entry into DANBIO.