Ankylosing spondylitis: a risk factor for myocardial infarction?

Objective To ascertain the prevalence of myocardial infarction (MI) in ankylosing spondylitis (AS) relative to that in the general population. Methods A questionnaire was sent to 593 patients with AS, aged between 50 and 75 years and registered at the Jan van Breemen Institute or VU University Medical Centre. A total of 383 (65%) patients with AS returned their questionnaire that covered the primary outcome, (non-fatal) MI. The prevalence of MI was calculated with data from the general population provided by Netherlands Information Network of General Practice databases as reference. Results The overall prevalence for MI was 4.4% in patients with AS versus 1.2% in the general population, resulting in an age-and gender-adjusted odds ratio of 3.1 (95% CI 1.9 to 5.1) for patients with AS. When non-responders (35%) were considered as non-MI the odds ratio decreased to 1.9 (95% CI 1.2 to 3.2). Conclusions These observations indicate that the prevalence of MI is increased in patients with AS.