COPENHAGEN — The increased risk for myocardial infarction in patients with rheumatoid arthritis starts to become apparent a year after rheumatoid arthritis is first diagnosed, based on a case-control study with more than 45,000 people.
“The increased risk of myocardial infarction [MI] is evident earlier in the course of rheumatoid arthritis [RA] than previously thought,” Marie Gunnarsson said at the annual European Congress of Rheumatology. “The finding underscores the need for early heart disease prevention measures in this population,” added Ms. Gunnarsson, an epidemiology researcher in the Institute of Environmental Medicine at the Karolinska Institute in Stockholm.
The study included 7,653 patients diagnosed with RA from 1996 to early 2007 and entered into the Swedish RA register. Each of these patients was newly diagnosed within 18 months from when RA symptoms first appeared. Each patient was matched by sex, age, and residential area with five people from the general Swedish population. Information on hospital discharges and deaths came from Swedish national registries. The average age of the RA patients and matched comparators was 57 years, and 71% were women.
During an average follow-up of almost 5 years in both groups, patients with rheumatoid arthritis faced a 70% increased risk for being hospitalized for an acute MI during the second through fourth year following their RA diagnosis, compared with controls, a statistically significant difference, Ms. Gunnarsson reported. Hospitalizations for MI also were 70% higher among patients with RA during years 5-10 following their arthritis. (See box.) In contrast, during the first year following RA diagnosis the patients also had an increased rate of MI hospitalizations compared with the controls in the study, but the difference was not large enough to be statistically significant.
The analysis showed no significant differences in the rates of MI death between the RA patients and controls during any follow-up period. The rate of death from any cause was also not significantly different between the two groups during most follow-up periods. The exception was during the period 5-10 years following RA diagnosis, when the RA patients had a 10% increased rate compared with the controls, a difference on the cusp of statistical significance. The pattern of MI hospitalizations in the two groups was similar regardless of whether RA was diagnosed in 1996, early 2007, or in between. Another analysis looked at the interaction of rheumatoid factor and MI hospitalizations. RA patients positive for rheumatoid factor had a slightly higher hospitalization rate than all RA patients, peaking with a rate two-fold the control rate at 5-10 years following RA diagnosis. RA patients negative for rheumatoid factor also showed higher rates of MI hospitalizations than controls, but the increase was not as high as in the rheumatoid factor-positive patients.
The study was funded in part by Astra Zeneca. Ms. Gunnarsson and her associates had no other disclosures.
http://www.rheumatologynews.com/article/PIIS1541980009702388/fulltextMany NSAIDs increase the chances of cardiovascular issues; I wonder what, if any, portion of this increased MI risk is due to NSAID use?