Cortical Thickness and Depressive Symptoms in Cognitively Normal Individuals: The Mayo Clinic Study of Aging

Article type: Research Article

Authors: Pink, Anna^a | Przybelski, Scott A.^b | Krell-Roesch, Janina^a | Stokin, Gorazd B.^c | Roberts, Rosebud O.^{d; e} | Mielke, Michelle M.^d | Knopman, David S.^e | Jack Jr., Clifford R.^f | Petersen, Ronald C.^{d; e} | Geda, Yonas E.^{a; d; g; h; *}

Affiliations: [a] Mayo Clinic Translational Neuroscience and Aging Program, Mayo Clinic, Scottsdale, AZ, USA | [b] Department of Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA | [c] International Clinical Research Center, St. Anne‘s University Hospital, Brno, Czech Republic | [d] Department of Health Sciences Research, Division of Epidemiology, Mayo Clinic, Rochester, MN, USA | [e] Department of Neurology, Mayo Clinic, Rochester, MN, USA | [f] Department of Radiology, Mayo Clinic, Rochester, MN, USA | [g] Department of Neurology, Mayo Clinic, Scottsdale, AZ, USA | [h] Department ofPsychiatry and Psychology, Mayo Clinic, Scottsdale, AZ, USA

Correspondence: [*] Correspondence to: Yonas E. Geda, MD, MSc, Mayo Clinic, Collaborative Research Building, 13400 East Shea Boulevard, Scottsdale, AZ 85259, USA. Tel.: +1 480 301 6284; Fax: +1 480 301 7017; E-mail: geda.yonas@mayo.edu.

Abstract: Altered cortical thickness has been observed in aging and various neurodegenerative disorders. Furthermore, reduced hippocampal volume has been reported in late-life depression. Even mild depressive symptoms are common in the elderly. However, little is known about the structural MRI measures of depressive symptoms in normal cognitive aging. Thus we sought to examine the association between depressive symptoms with cortical thickness and hippocampal volume as measured by brain MRI among community-dwelling participants. We conducted a cross-sectional study derived from the ongoing population-based Mayo Clinic Study of Aging, involving cognitively normal participants (N = 1,507) aged≥70 years. We observed that depressive symptoms were associated with lower global cortical thickness and lower thickness in specific prefrontal and temporal cortical regions, labeled by FreeSurfer software, version 5.3. As expected, the strength of correlation was very small, given that participants were community-dwelling with only mild depressive symptoms. We did not observe associations between hippocampal volume and depressive symptoms. These findings may provide insight into the structural correlates of mild depressive symptoms in elderly participants.

Keywords: Aging, cortical thickness, depression, depressive symptoms, magnetic resonance imaging

DOI: 10.3233/JAD-170041

Journal: Journal of Alzheimer's Disease, vol. 58, no. 4, pp. 1273-1281, 2017