Effect of age, gender, and time of day on pain-to-call times in patients with acute ST-segment elevation myocardial infarction: the CLOC'AGE study

Background. The time lapse between onset of symptoms and a call to an emergency dispatch center (pain-to-call time) is a critical prognostic factor in patients with chest pain. It is therefore important to identify factors related to delays in calling for help. Objective. To analyze whether age, gender, or time of day influence the pain-to-call delay in patients with acute ST. segment elevation myocardial infarction (STEMI). Methods. Data were extracted from a prospective registry of STEMI cases managed by 39 mobile intensive care ambulance teams before hospital arrival within 24 hours of onset in our region, the greater metropolitan area of Paris, France. We analyzed the relation between pain-to-call time and the following factors: age, gender, and the time of day when symptoms appeared. We also assessed the influence of pain-to-call time on the rate of prehospital decisions to implement reperfusion therapy. Results. A total of 24 662 consecutive patients were included; 19 291 (78%) were men and 4371 (22%) were women. The median age was 61 (interquartile range, 52-73) years (men, 59 [51-69] years; women, 73 [59-83] years; P<.0001). The median pain-to-call time was 60(24-164) minutes (men, 55 [23-150] minutes; women, 79 [31-220] minutes; P<.0001). The delay varied by time of day from a median of 40 (1 7-101) minutes in men between 5 pm and 6 pm to 149 (43-377) minutes in women between 2 am and 3 am. The delay was longer in women regardless of time of day and increased significantly with age in both men and women (P <.001). A longer pain-to-call time was significantly associated with a lower rate of implementation of myocardial reperfusion (P <.001). Conclusions. Pain-to-call delays were longer in women and older patients, especially at night. These age and gender differences identify groups that would benefit most from health education interventions.