OBJECTIVE Patients with rheumatoid arthritis (RA), a chronic inflammatory disease, have increased cardiovascular morbidity and mortality. We investigated whether early markers of RA inflammatory disease activity could predict later increased levels of pulse-wave velocity (PWV) and augmentation index (AIx), 2 measures of arterial stiffness. METHODS In total 238 patients with early RA were followed longitudinally and 108 were available for the 15-year followup examination. Comprehensive baseline clinical and radiographic data were collected in 1992. Arterial stiffness, measured as AIx and PWV (Sphygmocor apparatus), was recorded at the 15-year followup. Adjusted logistic univariate and multivariate analyses were performed with levels of AIx and PWV as the dependent variables, and variables reflecting baseline RA disease activity as possible predictors. The validity of the final models was examined in linear regression analyses. RESULTS Baseline C-reactive protein (CRP) above the median predicted increased AIx (OR 3.52, 95% CI 1.04-11.90) and PWV (OR 4.84, 95% CI 1.39-16.83) at the 15-year assessment in multivariate models. Patients with elevated baseline CRP had significantly higher AIx (ß = 2.67, 95% CI 0.06-5.31, p = 0.045) and lnPWV (ß = 0.08, 95% CI 0.01-0.14, p = 0.02) after 15 years, after adjustments for age, sex, heart rate (AIx only) and mean arterial pressure. CONCLUSIONS Inflammation early in the RA disease course was associated with increased AIx and PWV after 15 years. These findings support the importance of early control of the inflammatory process in patients with RA.