Background Patients with Rheumatoid Arthritis (RA) may present with various comorbidities resulting in worse treatment response.[1-2]

Objectives To investigate the impact of selected comorbid diseases on RA outcome with the aim of Disease Activity Score in 28 joints-C-Reactive Protein (DAS28-CRP).

Methods All our RA patients were included in this study. Patients’ demographics, serology results and DAS28-CRP at the time of diagnosis and after 4 months of treatment initiation were collected. Patients’ electronic hospital records were evaluated for a positive history of thyroid diseases, Diabetes Mellitus (DM), primary hyperparathyroidism, vitamin B12 deficiency and presence of other diagnosed autoimmune diseases.

Results 1035 RA patients were included. 63.4% were female, mean of age 67.1 years, mean of disease duration 9.6 years, 58.6% rheumatoid factor positive and 51.3% anti-cyclic citrullinated peptide positive. The observed prevalence of thyroid diseases was 11.8%, DM 10.4%, primary hyperparathyroidism 2.8%, vitamin B12 deficiency 5.8%, and other diagnosed autoimmune diseases 1.6%. There were significant associations between presence of thyroid diseases and female gender (p<0.001); DM and greater age (p<0.001); primary hyperparathyroidism and longer disease duration (p=0.002); other diagnosed autoimmune diseases and antinuclear antibody positivity (p<0.001). RA patients with thyroid diseases (p=0.001) and other comorbid autoimmune diseases (p<0.001) had significantly poorer initial response to the RA treatment compared to patients with isolated RA.

Univariate analyses revealed that age, presence of thyroid diseases, presence of other diagnosed autoimmune diseases and DAS28-CRP at the time of diagnosis were significantly associated with ∆DAS28-CRP. Additionally, multivariate analysis demonstrated that ∆DAS28-CRP deterioration was significantly correlated to the presence of thyroid diseases (unstandardized regression coefficient (standard error);-0.188(0.088),p=0.030) and presence of other diagnosed autoimmune diseases (-0.537(0.208),p=0.010). (table1)

Conclusions RA patients are at increased risk of specific comorbidities with possible impact on the treatment outcome. The authors, therefore, recommend to do periodical assessment of comorbidities to diagnose concurrent comorbid diseases as early as possible.

References: [1] Emamifar A, et al. Thyroid disorders in patients with newly diagnosed rheumatoid arthritis is associated with poor initial treatment response evaluated by disease activity score in 28 joints-C-reactive protein (DAS28-CRP): An observational cohort study. Medicine (Baltimore) 2017;96:e8357.

[2] Emamifar A, et al. Patients with newly diagnosed Rheumatoid Arthritis are at increased risk of Diabetes Mellitus: An Observational Cohort study. Acta Reumatol Port 2017 [Epub ahead of print].

Disclosure of Interest: None declared