Cardiovascular Comorbidities Relate More than Others with Disease Activity in Rheumatoid Arthritis

Abstract

Objectives: To explore the influence of comorbidities on clinical outcomes and disease activity in rheumatoid arthritis (RA).

Methods: In patients included in the cross-sectional observational multicenter international study COMORA, demographics, disease characteristics and comorbidities (hypertension, diabetes, hyperlipidemia, renal failure, ischemic heart disease, stroke, cancer, gastro-intestinal ulcers, hepatitis, depression, chronic pulmonary disease, obesity) were collected. Multivariable linear regression models explored the relationship between each comorbidity and disease activity measures: 28-swollen joint count (SJC), 28-tender joint count (TJC), erythrocyte sedimentation rate (ESR), patient's and physician's global assessment (PtGA, PhGA), patient reported fatigue and 28-Disease Activity Score (DAS28). Results are expressed as mean difference (MD) adjusted for the main confounders (age, gender, disease characteristics and treatment).

Results: A total of 3,920 patients were included: age (mean ±SD) 56.27 ±13.03 yrs, female 81.65%, disease duration median 7.08 yrs (IQR 2.97-13.27), DAS28 (mean ±SD) 3.74 ± 1.55. Patients with diabetes had more swollen and tender joints and worse PtGA and PhGA (MD +1.06, +0.93, +0.53 and +0.54, respectively). Patients with hyperlipidemia had a lower number of swollen and tender joints, lower ESR and better PtGA and PhGA (MD -0.77, -0.56, -3.56, -0.31 and -0.35, respectively). Patients with history of ischemic heart disease and obese patients had more tender joints (MD +1.27 and +1.07) and higher ESR levels (MD +5.64 and +5.20). DAS28 is influenced exclusively by cardiovascular comorbidities, in particular diabetes, hyperlipidemia, ischemic heart disease and obesity.

Conclusions: Cardiovascular comorbidities relate more than others with disease activity in RA. Diabetes and hyperlipidemia in particular seem associated with higher and lower disease activity respectively influencing almost all considered outcomes, suggesting a special importance of this pattern of comorbidities in disease activity assessment and clinical management.

Fig 1. Association between comorbidities and clinical and laboratory outcomes.

(A) The number of swollen and tender joints correlates significantly with diabetes and hyperlipidemia; tender joints correlate also with ischemic heart disease and obesity. (B) Erythrocyte sedimentation rate (ESR) correlates significantly with ischemic heart disease, obesity, hyperlipidemia and depression. (C) Physician’s global assessment (PhGA) was significantly associated with diabetes, hyperlipidemia and renal deficiency. (D) Patient’s global assessment (PtGA) correlates significantly with hypertension, diabetes, hyperlipidemia, cancer and chronic pulmonary disease; fatigue was significantly associated with diabetes, ischemic heart disease, gastro-intestinal ulcers, depression, chronic pulmonary disease and obesity.

Fig 2. Association between cardiovascular comorbidities and DAS28-ESR.

The correlation was statistically significant with concomitant diabetes, hyperlipidemia, ischemic heart disease and obesity. DAS28, Disease Activity Score using 28 joints.