Effects of use of specialty services on disease-modifying antirheumatic drug use in the treatment of rheumatoid arthritis in an insured elderly population

Abstract

Background: In community settings, disease-modifying antirheumatic drug (DMARD) use for rheumatoid arthritis (RA) falls short of treatment recommendations. This population-based study investigates the relationship between the use of DMARDs and specialty care in an insured population.

Method: A cohort of individuals aged 65 or older with RA was identified from a population-based physician billing database in Ontario, Canada, together with information on visit rates to general and specialist physicians and visit-specific diagnoses. DMARD prescription data were obtained from the Ontario Drug Benefits Plan database. The proportions of individuals with RA using DMARDs and specialist care were calculated for the 43 counties in Ontario, and the relationship between the 2 was determined using logistic multilevel modeling, controlling for possible confounders.

Results: A total of 13,698 RA individuals aged 65 or older were identified, representing 1% of the 65-or-older population. Within this cohort, 58% received DMARDs and 68% made 1 or more RA-related visits to a specialist in 3 years. There was considerable variation by county in both the proportion of those with RA making visits to specialists (39-82 per 100 RA population) and receiving DMARDs (36-81%). The use of DMARDs was significantly associated with the use of specialist services by individuals with RA (odds ratio 1.9 [95% confidence interval 1.87, 1.88] for counties with highest versus lowest proportional use of specialists) independent of effects of age, sex, income, and comorbidities.

Conclusion: Even in a universally funded setting, suboptimal treatment of RA is associated with lack of access to specialist services. These findings are likely applicable to many jurisdictions worldwide.