Psychological distress in coronary heart disease : Risk indicators, treatment and cardiovascular prognosis

The aims of this thesis were to: (1) explore factors associated with emotional distress; (2) investigate psychosocial stress as a risk factor for cardiovascular (CV) morbidity in patients with coronary heart disease (CHD); (3) investigate the impact of group-based stress management on psychological outcomes, and if that mediates risk of CV events; and (4) evaluate an internet-based cognitive behavioral therapy (iCBT) for emotional distress in patients with a recent myocardial infarction (MI). In Study I, data from the national registry SWEDEHEART on 27,267 MI patients < 75 years was used. Study II was a prospective longitudinal study with 14,577 patients with stable CHD. Psychosocial stress was assessed with a questionnaire and patients were followed-up for clinical events on average 3.7 years. In Study III, a group-based stress management was evaluated in a randomized controlled trial of 362 CHD patients. Psychological outcomes (stress, somatic anxiety, depression and vital exhaustion) were assessed at five time-points over two years. Joint modelling for longitudinal and time-to-event data was used to analyze if reduction in the psychological outcomes mediated the positive effect the treatment had on later CV events. Study IV describes Study V and includes a pilot study investigating the acceptability of the intervention used. In Study V 239 MI patients were recruited to evaluate iCBT versus usual care in a randomized clinical trial. In summary, in Study I, sociodemographic factors, previous psychiatric diagnosis and readmission for CV events were associated with incident and persistent emotional distress post-MI. In Study II, after multivariable adjustments, depressive symptoms, financial stress and living alone were all independently associated with CV death or the composite of CV death, non-fatal MI or non-fatal stroke. These results emphasize the importance of targeting psychosocial factors in order to optimize secondary prevention. In Study III, somatic anxiety was the only targeted psychological outcome affected positively by stress management, and may have in turn reduced subsequent CV events. Other mediating factors remain to be identified. Study IV indicated the intervention used in Study V was acceptable. Study V concluded that iCBT was not superior to usual care for emotional distress in post-MI patients and treatment adherence was unexpectedly low. Potential reasons for the low adherence require further exploration