Effects of cigarette smoking on cortical thickness in major depressive disorder


Zorlu N., Cropley V. L., Zorlu P. K., Delibas D. H., Adibelli Z. H., Baskin E. P., ...More

JOURNAL OF PSYCHIATRIC RESEARCH, vol.84, pp.1-8, 2017 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 84
  • Publication Date: 2017
  • Doi Number: 10.1016/j.jpsychires.2016.09.009
  • Journal Name: JOURNAL OF PSYCHIATRIC RESEARCH
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Social Sciences Citation Index (SSCI), Scopus
  • Page Numbers: pp.1-8
  • Keywords: Structural imaging, Major depressive disorder, Cigarette smoking, Cortical thickness, STATE FUNCTIONAL CONNECTIVITY, BRAINS DEFAULT NETWORK, SURFACE-BASED ANALYSIS, HUMAN CEREBRAL-CORTEX, GRAY-MATTER VOLUME, BODY-MASS INDEX, SUBCORTICAL VOLUME, WHITE-MATTER, METAANALYSIS, ONSET
  • Dokuz Eylül University Affiliated: Yes

Abstract

Findings of surface-based morphometry studies in major depressive disorder (MDD) are still inconsistent. Given that cigarette smoking is highly prevalent in MDD and has documented negative effects on the brain, it is possible that some of the inconsistencies may be partly explained by cigarette use. The aim of the current study was to examine the influence of cigarette smoking on brain structure in MDD. 50 MDD patients (25 smokers and 25 non-smokers) and 22 age, education, gender and BMI matched nonsmoker healthy controls underwent structural magnetic resonance imaging. Thickness and area of the cortex were measured using surface-based morphometry implemented with Freesurfer (v5.3.0). The non-smoker MDD patients had significantly increased cortical thickness, including in the left temporal cortex (p < 0.001), right insular cortex (p = 0.033) and left pre- and postcentral gyrus (p = 0.045), compared to healthy controls. We also found decreased cortical thickness in MDD patients who smoked compared to non-smoking patients in regions that overlapped with the regions found to be increased in non-smoking patients in comparison to controls. Non-smoker MDD patients had increased surface area in the right lateral occipital cortex (p = 0.009). We did not find any region where cortical thickness or surface area significantly differed between controls and either smoker MDD patients or all MDD patients. The findings of the current study suggest that cigarette smoking is associated with cortical thinning in regions found to be increased in patients with MDD. However, these results should be considered preliminary due to methodological limitations. (C) 2016 Elsevier Ltd. All rights reserved.