title: Sex differences in potential daily triggers of the onset of acute myocardial infarction: a case-crossover analysis among an Iranian population.
abstract: OBJECTIVE
  Despite an increasing knowledge of the importance of triggering in cardiac events and their mortality and morbidity, awareness concerning the types of physical and psychological triggers is unsatisfactory. This study aimed to address the main daily triggers of typical chest pain as a marker of acute coronary syndrome onset and assessed the sex-related differences regarding these triggers among Iranians.
  
  
  METHODS
  A case-crossover study was conducted on 198 consecutive patients with a first event of acute myocardial infarction admitted to the coronary care unit of Shafa hospital in Kerman. Patients were interviewed about the baseline characteristics as well as potential triggers of chest pain experienced over the day before the diagnosed onset of disease. The start of diagnostic chest pain was used as a marker of disease onset. The hazard period was defined as 12-h period of onset of chest pain.
  
  
  RESULTS
  Among probable triggers, only unsuspected sudden bad news and sexual activity had significant relationships with chest pain appearance during the hazard period. Among patients with the experience of bad news, the risk of chest pain occurrence during the hazard period was 6.9 [95% confidence interval (CI) 1.5-31.8]. Also, among those who were exposed to sexual activity, this risk was 3.4 (95% CI 1.1-10.4). Risk of chest pain following bad news was specific to men with a risk of 9.9 (95% CI 1.1-87.6) and risk of event following sexual activity was specific to women with a risk of 13.3 (95% CI 1.4-120.9).
  
  
  CONCLUSIONS
  Unsuspected sudden bad news can be an important trigger for acute cardiac events in men, whereas sexual activity can act as a strong trigger for these events among women. Counseling in high-risk groups should be focused on men with considerable sudden emotional stressors in their lives and also on women during the ages of active sexual function.
authors.affiliation: Shafa Hospital, Physiology, Research Center, Kerman University of Medical Sciences, Kerman, Iran. msv_swt@yahoo.com
authors.forename: Mohammad
authors.initials: M
authors.lastname: Masoomi
authors.forename: Jahangir
authors.initials: J
authors.lastname: Zare
authors.forename: Masoomeh
authors.initials: M
authors.lastname: Kahnooj
authors.forename: Ali
authors.initials: A
authors.lastname: Mirzazadeh
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Sheikhvatan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000208:ethnology / Q000209:etiology; D044466:Asian People / Q000706:statistics & numerical data*; D016009:Chi-Square Distribution; D003325:Coronary Care Units; D004644:Emotions; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000208:ethnology* / Q000209:etiology* / Q000523:psychology; D016017:Odds Ratio; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012725:Sexual Behavior / Q000208:ethnology; D013315:Stress, Psychological / Q000150:complications / Q000208:ethnology