Effects of cigarette smoking on cortical thickness in major depressive disorder. (January 2017)

• Record Type: Journal Article
• Authors: Zorlu, Nabi; Cropley, Vanessa Louise; Zorlu, Pelin Kurtgoz; Delibas, Dursun Hakan; Adibelli, Zehra Hilal; Baskin, Emel Pasa; Esen, Özgür Sipahi; Bora, Emre; Pantelis, Christos
• Is Part Of: Journal of psychiatric research. Volume 84(2017)
• Page Start: 1
• Page End: 8
• Publication Date: 2017-01
• Subjects: Structural imaging -- Major depressive disorder -- Cigarette smoking -- Cortical thickness; Psychiatry -- Periodicals; Mental Disorders -- Periodicals; Maladies mentales -- Périodiques; Psychiatry; Electronic journals; Periodicals; 616.89005
• DOI: 10.1016/j.jpsychires.2016.09.009
• Languages: English
• ISSNs: 0022-3956

Abstract

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 non-smoker 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. Highlights: Non-smoker MDD patients showed increased cortical thickness than non-smoker controls. Non-smoker MDD patients showed increased cortical thickness than smoker MDD patients. No differences between smoker MDD patients and non-smoker controls. Studies should take into account the importance of cigarette smoking. Cortical thickness seems to be increased in MDD patients.