Katharina Förster, MSc; Verena Enneking, MSc; Katharina Dohm, PhD; Ronny Redlich, PhD; Susanne Meinert, MSc; Adina Isabel Geisler, MSc; Elisabeth Johanna Leehr, PhD; Harald Kugel, PhD; Bernhard T. Baune, MD, MPH; Volker Arolt, MD; Pienie Zwitserlood, PhD; Dominik Grotegerd, PhD*; Udo Dannlowski, MD, PhD*
Background: Alexithymia is a risk factor for major depressive disorder (MDD) and has been associated with diminished treatment response. Neuroimaging studies have revealed structural aberrations of the anterior cingulate cortex and the fusiform gyrus in healthy controls with high levels of alexithymia. The present study tried to corroborate and extend these results to patients with MDD compared with healthy controls.
Methods: We investigated the relationship between alexithymia, depression and grey matter volume in 63 patients with MDD (mean age ± standard deviation = 42.43 yr ± 11.91; 33 female) and 46 healthy controls (45.35 yr ± 8.37; 22 female). We assessed alexithymia using the Toronto Alexithymia Scale. We conducted an alexithymia × group analysis of covariance; we used a region-of-interest approach, including the fusiform gyrus and anterior cingulate cortex, and conducted whole brain analysis using voxelbased morphometry.
Results: Our analysis revealed a significant alexithymia × group interaction in the fusiform gyrus (left, pFWE = 0.031; right, pFWE = 0.010). Higher alexithymia scores were associated with decreased grey matter volume in patients with MDD (pFWE = 0.009), but with increased grey matter volume of the fusiform gyrus in healthy controls (pFWE = 0.044). We found no significant main effects in the region-of-interest analysis.
Limitations: Owing to the naturalistic nature of our study, patients with MDD and healthy controls differed significantly in their alexithymia scores.
Conclusion: Our results showed the fusiform gyrus as a correlate of alexithymia. We also found differences related to alexithymia between patients with MDD and healthy controls in the fusiform gyrus. Our study encourages research related to the transition from risk to MDD in people with alexithymia.
*These authors contributed equally to the work and share senior authorship.
Submitted Feb. 25, 2019; Revised May 10, 2019; Accepted June 23, 2019; Published online Oct. 11, 2019
Affiliations: From the Department of Psychiatry, University of Münster, Münster, Germany (Förster, Enneking, Dohm, Redlich, Meinert, Geisler, Leehr, Baune, Arolt, Grotegerd, Dannlowski); the Institute of Clinical Radiology, University of Münster, Münster, Germany (Kugel); the Department of Psychiatry, University of Melbourne, Parkville, Australia (Baune); the Department of Psychology, University of Münster, Münster, Germany (Zwitserlood); and the Florey Institute for Neuroscience and Mental Health, University of Melbourne, Parkville, Australia (Baune).
Funding: This work was funded by the German Research Foundation (DFG, grant FOR2107 DA1151/5-1 and DA1151/5-2 to U. Dannlowski; SFB-TRR58, Projects C09 and Z02 to U. Dannlowski) and the Interdisciplinary Centre for Clinical Research (IZKF) of the medical faculty of Münster (grant Dan3/012/17 to U. Dannlowski).
Competing interests: H. Kugel received consultation fees from MR:comp GmbH, Testing Services for MR Safety, unrelated to the present work. V. Arolt is a member of the advisory board of, or has given presentations on behalf of, the following companies: Astra-Zeneca, Janssen-Organon, Lilly, Lundbeck, Servier, Pfizer, Otsuka, and Trommsdorff. K. Förster, V. Enneking, K. Dohm, R. Redlich, S. Meinert, A. Geisler, E. Leehr, B. Baune, P. Zwitserlood, D. Grotegerd and U. Dannlowski declare no competing interests.
Contributors: K. Förster, D. Grotegerd and U. Dannlowski designed the study. K. Förster, V. Enneking, K. Dohm, R. Redlich, S. Meinert, A.Geisler, E. Leehr, H. Kugel and D. Grotegerd acquired the data, which K. Förster, V. Enneking, R. Redlich, B. Baune, V. Arolt, P. Zwitserlood, D. Grotegerd and U. Dannlowski analyzed. K. Förster and U. Dannlowski wrote the article, which all authors reviewed. All authors approved the final version to be published and can certify that no other individuals not listed as authors have made substantial contributions to the paper.
Correspondence to: U. Dannlowski, Department of Psychiatry, University of Münster, Albert-Schweitzer-Campus 1, G A9, 48149 Münster, Germany; firstname.lastname@example.org