Background: One third of patients with rheumatoid arthritis have some comorbidity at the time of diagnosis and 80% during the evolution. The presence of each additional comorbidity reduces the chances of remission by 28%.

Objectives: To determine the prevalence of comorbidities in Rheumatoid Arthritis (RA) and to evaluate associated variables.

Methods: A descriptive cross-sectional study was conducted. It were included patients over 18 years of age, who attended the Rheumatology office between May and August 2018 with a diagnosis of RA according to the ACR 1987 and ACR/EULAR 2010 criteria. Demographic variables were studied along with disease-related variables (time of evolution, disease activity by DAS-28 and CDAI, treatment and functional capacity (HAQ-A)). The presence of comorbidities was evaluated using two indexes: Rheumatoid Arthritis Comorbidity Index (RACI) and Disease Comorbidity Index (RDCI). RACI consists of 31 comorbidities grouped into 11 categories: DAS 28 >3.6, local inflammation, smoking, tumors, systemic involvement, infection, vascular disease, bone health, mood, metabolic and cardiovascular disorders (score range 0-36). RDCI consists of 11 comorbidities (categories according to ICD-10) and a formula to calculate it (range 0-9). For both indexes; higher score, greater comorbidity.

Results: In this cross-sectional study, 345 patients were evaluated, of which 176 were included, 85.8% of the patients were female and the mean age was 52.7 ± 10.9 years; 31.2% of the cases finished primary school, the median of disease duration was 9 years (1-40), the mean DAS28 3.8 ± 1.4, and the mean CDAI 12.4 ± 11.3. 52.3% of the patients received treatment with glucocorticoids, 60.8% with NSAID, 60.2% with methotrexate, 39.2% with leflunomide, 17.6% with biologic DMARds and 5.6% with tofacitinib. 90.3% of the patients (95% CI 84.8, 94.3) presented some comorbidity measured by RACI. The average score was 4.7 ± 3.4 and the most frequent comorbidity were: elevated DAS28 (40.9%), dyslipidemia (38.1%), AHT (36.4%), prednisone >5 mg/d in 31.8%, endocrinopathies 19.3%. 73.3% of the patients had more than one comorbidity. Regarding RDCI, 47.2% of the cases presented some comorbidity with an average score of 0.95 ± 1.3; the most frequent were: AHT 36.4%, lung disease 12.5% and diabetes 8%. The oldest patients had more than one comorbidity (RACI), and also presented a higher HAQ score than those with only one (p<0.0001). Higher RACI score was associated with higher CDAI (p<0.001) and the use of glucocorticoids (p=0.008).

Conclusion: The prevalence of comorbidities in RA by RACI was elevated (90.3%) and 73.3% of the patients presented more than one comorbidity. The patients with the highest RACI score had higher disease activity and used glucocorticoids more frequently.

Disclosure of Interests: None declared