Comparison of Rheumatoid Arthritis Information Recorded in UK CPRD Aurum and CPRD GOLD Databases (Companion Paper 3)

Abstract

Purpose

To report distribution of codes associated with a rheumatoid arthritis (RA) diagnosis recorded in Clinical Practice Research Datalink (CPRD) Aurum compared to the previously validated CPRD GOLD database as a critical step toward making decisions about CPRD Aurum’s suitability for medical research.

Patients and Methods

We analyzed the distribution of codes for RA diagnoses, labs, and treatments in the new CPRD Aurum database, compared to the CPRD GOLD database by selecting relevant indicators of RA diagnosis, treatment, and clinical care. We included all patients in England in CPRD Aurum and CPRD GOLD with an incident diagnosis code for RA on or after 1 January 2005 and at least two years recorded data before first RA diagnosis.

Results

We found 53,083 and 18,167 patients with a new diagnosis code for RA in CPRD Aurum and CPRD GOLD, respectively. In both databases approximately 67% were female with similar mean ages at first diagnosis. There were few differences in RA-related recording patterns between the two data sources. Before first RA diagnosis, CPRD Aurum patients had more RA-specific labs and other supporting clinical codes. After diagnosis, CPRD Aurum patients had more RA diagnoses coded and more often had 10+ general RA labs than patients in CPRD GOLD. More CPRD GOLD patients had 10+ prescriptions for conventional disease-modifying antirheumatic drugs (cDMARD) compared to CPRD Aurum. Otherwise, the distribution of drugs used to treat RA was similar between databases. The standardized incidence of RA was similar between databases.

Conclusion

Overall, among patients with a diagnosis code for RA, recording of diagnoses, prescription drugs, and labs were similar between CPRD Aurum and CPRD GOLD. Slight differences were found for a few variables, but overall, we found consistency between the databases. In addition, standardized incidence of RA was similar between databases.

Keywords:

• Clinical Practice Research Datalink
• CPRD Aurum
• CPRD GOLD
• validation
• data quality

Acknowledgments

The abstract of this paper was presented at the 38th International Conference on Pharmacoepidemiology and Therapeutic Risk Management (ICPE) as a poster presentation with interim findings. The poster’s abstract was published in “Poster Abstracts” in Pharmacoepidemiology and Drug Safety (PDS): https://doi.org/10.1002/pds.5518.

Disclosure

Dr Catherine Vasilakis-Scaramozza, Ms Katrina Wilcox Hagberg, Ms Rebecca Persson, and Dr Susan Jick report that the BCDSP (employer) received contractual research grants from Amgen during the conduct of the study. Dr George Kafatos, Dr Joe Maskell, and Dr David Neasham are employees of Amgen Ltd and own shares of Amgen Inc. Dr Susan Jick reports she is a member of the Amgen Methods Council. The authors report no other conflicts of interest in this work.

Additional information

Funding

This study was funded by Amgen, Inc.