Vital exhaustion and coronary artery disease in women : Biological correlates and behavioral intervention

Sammanfattning: Background: Vital exhaustion - a state characterized by unusual fatigue, irritability, and demoralization - is a predictor of coronary heart disease (CHD). The physiological mechanisms mediating this effect are not fully understood. Vital exhaustion may be decreased by means of behavioral modification. However, it is yet not established what that may translate into in terms of coronary risk factor modification. Previous studies of vital exhaustion are based on predominantly male samples and it is yet unclear to what extent the results pertain to women. Studies including larger samples of women may be warranted because they, in comparison to men, may have a worse prognosis after a coronary event, are more exhausted, and show a poorer response to cardiac rehabilitation. Aims: To examine 1) the effect of vital exhaustion on prognosis and 2) the relationship between vital exhaustion, cortisol and coronary artery disease (CAD) in women with CHD, 3) to examine the relationship between vital exhaustion, lifestyle variables, and lipid profile in healthy women, 4) to evaluate the effects or stress management, with regard to vital exhaustion, depression and biological risk factors in women with CHD, and 5) to evaluate the effects of a lifestyle change program, with regard to quality of life (including vitality) and biological risk factors in men and women with CHD. Materials and Methods: Study I-III are based on a population-based case-control study of women <65 years who were admitted to a coronary care unit for acute coronary syndrome (ACS), and healthy, age-matched controls. At 3-6 months after hospitalization, vital exhaustion was assessed by means of an early version of the Maastricht Questionnaire (MQ), lifestyle variables were assessed by standardized questionnaires, and biological factors by clinical examination, including coronary angiography. Furthermore, the women with CHD were followed for five years for recurrent coronary events. Study IV is based on a randomized controlled intervention study evaluating the effect of a 1-year stress management program, specifically aimed at reducing stress in women with CHD. Patients were 247 women (age 62±9 years) recruited consecutively during the event of either acute myocardial infarction (AMD, percutaneous transluminal angioplasty, or coronary by-pass operation. Patients were randomly assigned to either stress management (twenty 2-hour sessions during 1 year) and medical care by a cardiologist, or to the control group obtaining usual care of the health care system. At 6-8 weeks after randomization, at 10 weeks, at 1 year, and at 1-2 years follow-up vital exhaustion was assessed by means of the MQ, depression by the Beck Depression Inventory, and biological variables were determined by clinical examination. Study V is a descriptive study of men and women with CHD who participated in a 1-year comprehensive lifestyle change program. The program aimed at improving diet, exercise, stress management, and social support to prevent coronary morbidity and improve quality of life. Spousal participation was encouraged. At baseline, at 3 months, and at 1 year quality of life (including vitality) was assessed by means of MOS SF-36 Health Survey, and medical variables were determined by clinical examination. Results: A vital exhaustion score above the median predicted a recurrent coronary event by a factor of two, HR 2.2 (95% CI 1.2-4.1) in women who recently suffered an AMI; vital exhaustion had an additive, but not an independent, effect on probability of CAD in women with ACS (OR=2.9, 95% Cl 1.3-6.2); elevated cortisol levels were found in patients with significant CAD (p<0.01); vital exhaustion a positive association was found between vital exhaustion and cortisol (p=0.05); and divided into quartiles, vital exhaustion was inversely related to high-density lipoprotein and to apolipoprotein Al in a linear fashion (p<0.05). These results remained after adjusting for standard CHD-risk factors. Furthermore, in women with CHD, vital exhaustion was positively related to a sedentary lifestyle. Stress management, as compared to usual care, was associated with a more rapid decrease of vital exhaustion (p=0.005); and both men and women participating in a comprehensive lifestyle change program evidenced improvements regarding quality of life (including vitality) and medical characteristics (p<0.001), women improved comparably to men despite their worse overall status at baseline. Conclusions: This thesis demonstrates that vital exhaustion is an independent marker of poor prognosis in women with CHD. Sedentary lifestyle, increased activity of the sympathetic nervous system, and lipid abnormalities may be involved in this relationship. These findings fit with previous investigations performed in predominantly male populations. Furthermore, this thesis shows that women's response to cardiac rehabilitation may be as good as men's, and that stress management in a supportive group setting appears attractive to women with CHD. Implementation of these components into cardiac rehabilitation programs may be one way of increasing female participation-rates, which have been traditionally low.