The nature of the depressive symptomatology preceding myocardial infarction.

Little is known about the nature of the depressive symptomatology preceding myocardial infarction (MI). Specification of the depressive symptomatology is important for the development of hypotheses about the biological mechanisms relating depressive symptoms to MI. To test the hypothesis that feelings of fatigue and loss of energy have the strongest predictive power of all depressive symptoms, the authors reanalyzed data from a prospective study of 3877 healthy men aged 40 to 65 years. The men's mental state was assessed using the Maastricht Questionnaire, a scale that measures vital exhaustion, which is characterized by unusual fatigue and lack of energy, increased irritability, and depressive symptoms, including demoralization. Oblique factor analysis was used to validate these dimensions. Results of Cox's regression analyses showed that the fatigue subscale has the strongest predictive power for incident MI and that depression and irritability subscales lose their predictive power when controlled for fatigue.