Early warning signs of an acute myocardial infarction and their influence on symptoms during the acute phase, with comparisons by gender.

BACKGROUND: Identifying early warning signs of an acute myocardial infarction (AMI) may aid in the early diagnosis of coronary artery disease.
OBJECTIVES: This study was conducted to assess early warning signs (prodromal symptoms) of AMI, with comparisons made by gender. Another aim was to determine whether these early warning signs had any influence on the patients' acute symptoms of AMI.
METHODS: This was a multicenter, cross-sectional study of Norwegian patients (aged <or=75 years) hospitalized with their first AMI. A self-administered questionnaire was used to gather information on prodromal symptoms, defined as pain in the chest, pain in the shoulder or back, radiating pain or numbness in the arms, dyspnea, and fatigue. Symptoms were reported for the year before AMI and during the acute stage. Logistic regression analyses were used to examine the association between prodromal symptoms and acute symptoms and the effect of medical history (hypertension, diabetes, and hypercholesterolemia).
RESULTS: The self-administered questionnaire had a 72% response rate; the study included 149 women and 384 men diagnosed with first-time AMI. Symptoms occurring during the year before AMI included pain in the chest in 45% (240/533), shoulder or back pain in 51% (270/533), arm pain in 38% (205/533), dyspnea in 33% (176/533), and fatigue in 62% (330/533). There were no statistically significant gender differences. The risk of experiencing chest symptoms in the acute phase was >5 times higher in women who had experienced prodromal symptoms in the chest (adjusted odds ratio [OR] = 5.11; 95% CI, 1.38-18.88) and nearly 3 times higher in men (OR = 2.80; 95% CI, 1.17-6.70). The risk of experiencing shoulder or back pain was almost 5 times higher in men with prodromal shoulder or back pain (OR = 4.96; 95% CI, 3.01-8.19), but no statistically significant association was found in women. The risk of experiencing radiating arm pain or numbness in the acute phase was more than doubled in women with prodromal arm pain (OR = 2.68; 95% CI, 1.19-6.20) and more than tripled in men with prodromal arm pain (OR = 3.11; 95% CI, 1.90-5.07). The risk of experiencing dyspnea in the acute phase was more than doubled in women with prodromal dyspnea (OR = 2.67; 95% CI, 1.25-5.71) and >5 times higher in men with prodromal dyspnea (OR = 5.73; 95% CI, 3.42-9.62). Finally, the risk of fatigue was almost tripled in women (OR = 2.97; 95% CI, 1.28-6.85) and more than doubled in men (OR = 2.51; 95% CI, 1.54-4.11). Hypertensive women, but not men, were less likely to experience chest symptoms in the acute phase (OR = 0.29; 95% CI, 0.10-0.82).
CONCLUSIONS: Almost half of the study patients (45%) experienced prodromal chest symptoms the year before their first AMI. These prodromal symptoms predicted the symptoms that occurred during the acute stage of AMI, with some differences between the sexes.