Cardiac parasympathetic dysfunction related to depression in older adults with acute coronary syndromes Salvador M. Guinjoan * , M. Soledad Ladro ´n de Guevara, Carolina Correa, Silvina I. Schauffele, Leonardo Nicola-Siri, Rodolfo D. Fahrer, Enrique Ortiz-Fra ´gola, Jose ´ A. Martı ´nez-Martı ´nez, Daniel P. Cardinali Department of Mental Health and Coronary Care Unit, Hospital de Clı ´nicas ‘‘Jose ´ de San Martı ´n’’, University of Buenos Aires School of Medicine, Buenos Aires, Argentina Received 12 June 2002; accepted 3 February 2003 Abstract Objective: To determine whether depression is associated with cardiac autonomic alterations in elderly patients with recent acute coronary syndromes (ACSs). Methods: Cross-sectional study on the association between a major depressive episode or isolated depressive symptoms (21-item Hamilton depression score) and heart rate variability abnormalities in 56 adults (31 women, 55%) 60 years of age and older with a recent (24 – 72 h) myocardial infarction (MI) or unstable angina (UA). Results: Spectral and nonspectral parameters of respiratory sinus arrhythmia, indicative of parasympathetic activity on the heart, were decreased in patients with depression (high-frequency heart rate variability [log ms 2 ] 2.12 F 0.4 vs. 2.52 F 0.5, P = .024; pNN50 [%] 1 F 2 vs. 9 F 15, P = .006; and rMSNN [ms] 16 F 6 vs. 28 F 22, P = .009). Also, high-frequency heart rate variability decreased with increasing depressive symptom severity. Conclusion: In a sample of older adults suffering from ACSs, depression was associated with impaired parasympathetic control of the heart. D 2004 Elsevier Inc. All rights reserved. Keywords: Autonomic; Coronary; Depression; Geriatrics; Heart; Vagal Introduction The relationship between depression and coronary heart disease has been the subject of much investigation in recent years [1]. Specifically, it is well determined that after an acute myocardial infarction (MI), major depression is asso- ciated with a significant increase in mortality 6 months after the event [2–4]. Lespe ´rance et al. [5] obtained similar findings in patients who had an episode of unstable angina (UA) and proposed that MI and UA could be studied together regarding the effect of depression on their pro- gnosis. In fact, MI and UA are collectively referred to as acute coronary syndromes (ACSs) on the basis of their shared pathophysiology [6 – 8]. Factors proposed to explain the worsening of ACS prognosis induced by depression include poor compliance with cardiac treatment regimen, increased platelet aggrega- tion and disturbed autonomic tone to the heart [1,9 –11]. The latter factor has been studied in patients with an acute MI [10,12], and it was observed that depression is associated to decreased heart rate variability parameters, indicating impaired cardiac autonomic control. There are no reports available on the relationship between depres- sion and autonomic tone of UA survivors, although in general, cardiac autonomic activity alterations are similar in MI and UA [13]. ACS are also highly prevalent among older adults [14], but few studies are available focusing on the association between depression and cardiac auto- nomic dysfunction in this age group [15]. Finally, most studies refer to patients with stable coronary artery dis- ease, even when factors influencing post-ACS mortality within the first month are not the same as predictive factors of mortality in patients with chronic angina pec- toris [16]. The purpose of the present study was to ascertain whether depression is associated with abnormal autonomic input to the heart in older adults with a recent (i.e., < 72 h) ACS. 0022-3999/04/$ - see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/S0022-3999(03)00043-6 * Corresponding author. Department of Mental Health, Jose ´ de San Martı ´n Hospital, Ave. Co ´rdoba 2315, 5th Floor, 1121 Buenos Aires, Argentina. Tel.: +54-11-5950-8836; fax: +54-11-5950-8865. E-mail address: guinjoan@fmed.uba.ar (S.M. Guinjoan). Journal of Psychosomatic Research 56 (2004) 83 – 88