We recently reported that rheumatoid arthritis (RA) patients had increased intima-media thickness (IMT) of the common carotid artery (CCA). The present longitudinal study was performed to determine whether the change in arterial thickness was accelerated in RA patients and to determine which factor was important in the progression of arterial wall changes.
We studied 62 female RA patients with stable disease activity and 63 healthy female controls. IMT of the CCA was measured twice by high-resolution B-mode ultrasonography. The second examination was performed 18-36 months after the first, and changes were expressed as millimeters of increase per year. Baseline examinations included blood markers of inflammation and urinary calcium excretion (expressed as the calcium-to-creatinine ratio).
RA patients showed a significantly greater increase in IMT of the CCA compared with controls. In univariate analyses of the RA patient data, the C-reactive protein (CRP) level correlated with the increase in CCA IMT. Other markers of inflammation (the erythrocyte sedimentation rate and white blood cell and platelet counts) also showed significant positive associations with the annual increase in CCA IMT in multiple regression models when adjusted for age, smoking status, blood pressure, and serum cholesterol level. The urinary calcium-to-creatinine ratio was also significantly associated with an increase in CCA IMT. Moreover, both the CRP level and the urinary calcium-to-creatinine ratio were significantly and independently associated with the increase in IMT of the CCA.
Patients with RA have a higher rate of increase in thickening of the arterial wall. Inflammation and calcium mobilization are factors closely associated with the accelerated arterial wall changes.