Cardiovascular admissions and mortality in an inception cohort of patients with rheumatoid arthritis with onset in the 1980s and 1990s

Abstract

Background: There is increased cardiovascular disease mortality in rheumatoid arthritis. This may reflect an increased prevalence of cardiovascular disease or an increased case fatality in patients with rheumatoid arthritis.

Objectives: To examine whether rheumatoid patients with disease onset in the 1980s-1990s have increased mortality, and to compare cardiovascular admission rates in rheumatoid patients with those of the general population.

Methods: An inception cohort of 1010 rheumatoid patients attending Stockport rheumatology clinics between 1981 and 1996 was followed up to December 2002 through the Office for National Statistics. Standardised mortality ratios (SMR) were calculated for all-cause and cause specific mortality, using the population of Stockport as reference. Cardiovascular disease admission rates were ascertained for a subgroup of patients using national hospital episode statistics; standardised cardiovascular disease admission rates (SAR) and SMRs were calculated for this subgroup.

Results: 470 patients (48%) died during a median follow up of 11.4 years. All-cause mortality was increased in men (SMR = 1.45 (95% confidence interval, 1.22 to 1.71)) and women (SMR = 1.84 (1.64 to 2.05)), as was cardiovascular disease mortality in men (SMR = 1.36 (1.04 to 1.75) and women (SMR = 1.93 (1.65 to 2.26)). No difference in cardiovascular disease admission rates was observed in men (SAR 1.20 (0.89 to 1.58) or women (SAR = 1.10 (0.88 to 1.36)), despite excess cardiovascular disease mortality in this subgroup.

Conclusions: Patients with rheumatoid arthritis have reduced life expectancy and excess cardiovascular disease mortality. Nevertheless, standardised admission rates for cardiovascular disease were not raised. This suggests either that cardiovascular disease in rheumatoid arthritis has a higher case fatality than in the general population or that it often goes unrecognised before the fatal event.