Aging, stress, and sudden cardiac death

Cardiac arrhythmia leading to sudden death is a common disease of middle age, but its impact on the survival and function of older adults has been largely ignored. This is in spite of the facts that (a) cardiovascular diseases already complicate or account for 25% of the dementias: (b) as many as half of all sudden deaths occur in individuals 75 years or olders; and (c) 30%-50% of those resuscitated are left with significant cognitive deficits. Age-related stressors (bereavement, social isolation, retirement dissatisfaction, changes in major life events, and household size) have been empirically linked to cardiovascular mortality, and there is reason to believe that the unifying emotional result of these stressors is episodic depression. We studied 88 patients during acute treatment for life-threatening arrhythmia. Follow-up mortality was significantly related to depression and cognitive impairment found at initial assessment. Impairment correlated with measures of depression, functional status, heart failure, and ventricular tachycardia, but not arrhythmia severity or treatment efficacy. Our results from middle-aged adults suggest that therapeutic advances that increase the number of arrhythmia survivors may proportionately raise the percentage of vascular dementia cases in the elderly and that some degree of the observed morbidity and mortality may be a manifestation of depression and dementia. If confirmed, these findings would also indicate that psychosocial interventions, in addition to biomedical advances, will be needed to maximally reduce sudden cardiac mortality and arrhythmia-related morbidity. We suggest that psychosocial interventions for patients at risk for sudden death focus on (a) reduction of age-related stressors through (b) aggressive treatment of depression and (c) early identification of and preparation for the behavioral sequelae of cognitive impairment.