Share this!

register today

Earn Free CME Credits by reading the latest medical news in your specialty. sign up

A Canadian analysis has reported that early rheumatoid arthritis (ERA) patients in indigenous populations more often presented with poor prognostic factors and had higher disease activity compared with Caucasian patients. Despite having comparable treatment regimens, such patients were less likely to achieve remission and show improvement in patient global and pain scores.

Cheryl Barnabe, MD, of the University of Calgary in Alberta, and colleagues published findings from the nationwide prospective Canadian early ArThritis CoHort (CATCH) study, now online in Arthritis Care & Research.

The study followed ERA patients enrolled in CATCH at academic and community rheumatology clinics during the period of 2007-2016. The mean age of patients was about 55, and about 70% were women. At inception, the 2,173 participants, including 100 (5%) identifying as Aboriginal and 2073 as Caucasian, had similar mean symptom durations of 189 and 179 days, respectively (standard deviations 93 and 91 days). Both groups had comparable Disease Activity Scores in 28 Joints (DAS28) of 4.97 and 4.86, as well as similar Health Assessment Questionnaire scores of 0.93 and 0.88.

The investigators controlled for a large number of demographic, clinical, and lifestyle variables.

Although several factors linked to poor prognosis affected more Aboriginal participants, disease-modifying therapy selection and frequency of therapy escalation were similar in both ethnicities, the team reported.

In terms of outcomes, DAS28 remission was achieved less frequently in Aboriginal than Caucasian participants: 43.6% versus 70.0% throughout follow-up (adjusted OR 0.39, 95% CI 0.25-0.62). The Aboriginal group also had slower improvement in swollen joint counts and experienced only non-significant improvement in patient global scores. In addition, the pain levels remained higher. Over time, however, improvements in function and physical global scores were similar in both groups.

The findings point to disparities in sociodemographic and prognostic factors associated with inequities in social determinants of health for indigenous ERA patients and highlight the need for population-level strategies aimed at health equity, as well as more tailored therapeutic approaches, Barnabe et al suggested. "Further examination of the efficacy of treatment strategies applied in different contexts is required."

Treatment regimens were comparable by ethnicity at inception and over time. In initial treatment, 23% of the Caucasian and 29% of the Aboriginal patients received methotrexate monotherapy, 52% of Caucasians and 53% of Aboriginals received disease-modifying antirheumatic drug (DMARD) combination therapy, and 4% of Caucasians and 3% of Aboriginals received biologic therapy. About a quarter of all patients took oral steroids.

Over follow-up, ever use of oral steroids was 37% in both groups, while 89% and 83%, respectively, were prescribed methotrexate monotherapy. Combination DMARDs were given to 72% of the Aboriginal and 67% of Caucasian participants, while biologic therapies were given to 12% and 17%, respectively.

Dose escalation with DMARDs, biologics, and/or oral steroids was noted in 33% of Aboriginal and 34% of Caucasian patients who were in DAS28 moderate or high disease activity. Therapy with DMARD and/or biologic therapy (without the consideration of oral steroid in the escalation definition) was escalated at 17% and 18% of visits where Aboriginal and Caucasian patients were in DAS28 moderate or high disease activity.

Seeking to explain the outcome discrepancies, the researchers noted that First Nations populations have genetic risk factors for a more aggressive disease phenotype, such as a high prevalence of HLA shared epitope alleles as well as a high prevalence of RA autoantibodies, including anti-citrullinated protein antibodies and anti-carbamylated protein antibodies. In addition, Aboriginal people have increased environmental exposures such as smoking and periodontal disease. Critical roles are played in prognostic factors such as seropositive status, income, education, body mass index, […]

(Visited 2 times, 1 visits today)

Share this!