a1 Department of Psychiatry, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
a2 Department of Old Age Psychiatry, De Gelderse Roos, Arnhem, The Netherlands
a3 Department of General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
a4 Department of Human Genetics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
a5 Psychiatry Research Group, School of Community-Based Medicine, University of Manchester, Manchester, UK
a6 Department of Epidemiology and Biostatistics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
a7 Department of Cognitive Neuroscience, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
a8 University Centre of Psychiatry, University Medical Centre Groningen, Groningen, The Netherlands
Background Depression increases the risk of subsequent vascular events in both cardiac and non-cardiac patients. Atherosclerosis, the underlying process leading to vascular events, has been associated with depression. This association, however, may be confounded by the somatic-affective symptoms being a consequence of cardiovascular disease. While taking into account the differentiation between somatic-affective and cognitive-affective symptoms of depression, we examined the association between depression and atherosclerosis in a community-based sample.
Method In 1261 participants of the Nijmegen Biomedical Study (NBS), aged 50–70 years and free of stroke and dementia, we measured the intima–media thickness (IMT) of the carotid artery as a measure of atherosclerosis and we assessed depressive symptoms using the Beck Depression Inventory (BDI). Principal components analysis (PCA) of the BDI items yielded two factors, representing a cognitive-affective and a somatic-affective symptom cluster. While correcting for confounders, we used separate multiple regression analyses to test the BDI sum score and both depression symptom clusters.
Results We found a significant correlation between the BDI sum score and the IMT. Cognitive-affective, but not somatic-affective, symptoms were also associated with the IMT. When we stratified for coronary artery disease (CAD), the somatic-affective symptom cluster correlated significantly with depression in both patients with and patients without CAD.
Conclusions The association between depressive symptoms and atherosclerosis is explained by the somatic-affective symptom cluster of depression. Subclinical vascular disease thus may inflate depressive symptom scores and may explain why treatment of depression in cardiac patients hardly affects vascular outcome.
(Received June 02 2010)
(Revised September 24 2010)
(Accepted October 04 2010)
(Online publication December 10 2010)
c1 Address for correspondence: B. A. A. Bus, M.D., Department of Psychiatry, Radboud University Nijmegen (RUN) Medical Centre, Reinier Postlaan 10, 6525GC Nijmegen, The Netherlands. (Email: firstname.lastname@example.org)
† Participating as representative of the Nijmegen Biomedical Study.