Impact of old age on clinical and angiographic characteristics of coronary artery spasm as assessed by acetylcholine provocation test

BACKGROUND Smoking and other risk factors have been well known as important factors of variant angina or coronary artery spasm (CAS). However, clinical features related to age on coronary artery spasm have been rarely evaluated. METHODS We evaluated 3155 consecutive patients with insignificant coronary artery lesion. Patients underwent Acetylcholine (Ach) provocation test for induction of CAS. CAS was defined as > 70% luminal narrowing of coronary arteries during Ach provocation test. The results of Ach provocation test were compared among age groups; < 45 years (Group 1), 45-54 years (Group 2), 55-64 years (Group 3), and ≥ 65 years (Group 4). RESULTS Older patients had higher incidence of hypertension, diabetes, but lower incidence rate of current smoking, male sex compared with younger patients. Positive Ach provocation test finding was frequently showed with aging (47.36% vs. 58.3% vs. 62.6% vs. 61.5%; P < 0.001). Multivariate logistic analysis showed that age, male, and myocardial bridge were independent predictors of CAS induced by Ach provocation test. CONCLUSION Our present study showed that old age was independent predictor for Ach-induced significant coronary artery spasm.