To investigate the overall and the cardiovascular mortality in rheumatoid arthritis (RA) in Northern Sweden. To analyze the effect of traditional risk factors and factors associated with rheumatoid disease and its treatment on the progression of cardiovascular disease (CVD) and on mortality by all causes.
A cohort of 606 patients with seropositive RA were followed from 1979 to the end of 1994 or to the death of the patient. Standardized mortality ratio and survival curves were estimated with the population of Vasterbotten as reference. Sex, age at disease onset, treatment with corticosteroids, use of disease modifying antirheumatic drugs (DMARD) and hormone replacement therapy (HRT), hypertension, diabetes mellitus, HLA types, and cause of death were recorded from disease onset. Cox's proportional hazards regression was used to identify important predictors for death and cardiovascular event during followup.
The standardized mortality ratio in both sexes was significantly higher (1.57) for all underlying causes together, for CVD (1.46) and for ischemic heart disease (IHD) (1.54) compared to the reference population. The death rate increased over time. In multiple Cox regression analyses, male sex, higher age at disease onset, and former cardiovascular event increased the death rate. Male sex, high age at disease onset, and hypertension increased the risk of cardiovascular event. Diabetes mellitus, treatment with corticosteroids, DMARD, or HRT did not influence the risks of death or first cardiovascular event.
The overall mortality and death due to CVD and IHD were in both sexes increased in seropositive RA. Male sex and high age at disease onset predicted death and cardiovascular event. Except for hypertension, which increased the risk for cardiovascular event, neither of these traditional cardiovascular risk factors nor corticosteroid treatment influenced mortality by all causes or by cardiovascular event.