An increasing number of comorbidities in patients with rheumatoid arthritis correlates with a lower likelihood of reaching treatment targets, according to an analysis conducted with a series of large real-world datasets and presented in a symposium sponsored by the Rheumatology Research Foundation.
When compared to those with the lowest burden of comorbidity in one of these analyses, those with the highest had a nearly 50% lower likelihood (odds ratio, 0.54; 95% confidence interval [CI], 0.34-0.85) of achieving low disease activity or remission, according to Bryant England, MD, PhD, assistant professor in the division of rheumatology at the University of Nebraska, Omaha.
“Patients with more comorbidities struggle to reach treatment targets,” Dr. England said. In the treatment of RA, “we typically focus only on the joints, but these data suggest we need to begin to think more holistically about managing these patients.”
Both the American College of Rheumatology (ACR) and the European Alliance of Associations for Rheumatology (EULAR) endorse a treat-to-target management approach in RA guidelines, but only a proportion of patients reach their targets, according to Dr. England. In his series of analyses, Dr. England has been exploring the role of comorbidities as one of the contributing factors.
Looking for real-world data, Dr. England evaluated comorbidities in the Veterans Affairs Rheumatoid Arthritis Registry, which has a male predominant population, the National Databank for Rheumatic Diseases, which is female predominant, the Truven Health Analytics MarketScan Database, and the Rheumatology Informatics System for Effectiveness Registry (RISE).
Comorbidities accrue more quickly in RA patients
All of these real-world data support the premise that comorbidities are higher in patients with RA than in those without, and show that the burden of comorbidities rises more quickly in patients with RA. For example, the average number of comorbidities in the MarketScan database of recently diagnosed RA patients was 2.6. Five years later, the average doubled to more than 5. For those without RA, the average at the baseline evaluation was 1.6 and remained below 3 at 5 years.
For the burden of comorbidities in RA, Dr. England prefers the term “multimorbidity” because he believes it captures the interconnections of these chronic diseases, many of which trigger or exacerbate others. When he looked at health history 2 years before the RA diagnosis, multimorbidities were already somewhat higher, but he found that burden “takes off” in the peri-diagnostic period and climbs steeply thereafter.
“The data tell us that multimorbidity becomes more problematic throughout the RA disease course,” said Dr. England, who published some of these data only a few weeks prior to his presentation.
In one effort to evaluate how multimorbidity affects treatment choices and outcome, he selected patients with persistently active disease from the RISE registry, a group expected to be candidates for a treatment change or escalation. The data suggested patients with multimorbidity were less likely than were those without to receive a change of therapy in response to their active disease, but it also demonstrated that patients with multimorbidity were less likely to achieve remission or low disease activity even if the medications were changed.