Nicola PJ et al. (2006) Contribution of congestive heart failure and ischemic heart disease to excess mortality in rheumatoid arthritis. Arthritis Rheum 54: 60–67

Mortality in patients with rheumatoid arthritis (RA) is higher than in the general population. Deaths caused directly by RA are rare; the additional deaths must, therefore, result from other conditions. It is not known, however, to what extent individual comorbidities contribute to excess mortality in patients with RA.

Researchers at the Mayo Clinic investigated the contributions of ischemic heart disease and of congestive heart failure (CHF) to mortality in patients with RA, in a retrospective study of 603 individuals diagnosed between 1955 and 1995, matched with a non-RA control population. There were 345 deaths in the RA group compared with 222 in the control group. Statistically, there was no difference in the incidence of myocardial infarction or ischemic heart disease between the groups, but the incidence of CHF was significantly higher in the RA group (37.1% versus 27.7%, P <0.001). As the death rate for patients with heart conditions was similar in both groups, it seems that the increased incidence of CHF in the RA population is primarily responsible for the excess deaths attributable to CHF in patients with RA.

The reasons for the increased incidence of CHF observed in RA are unclear. It has been reported that high levels of systemic markers of inflammation are predictive of CHF, and C-reactive protein has been found to be a risk factor for the condition. Pericardial and valve disease, which are possible complications of RA, and potential cardiotoxic effects of RA drugs, could also be implicated.