title: Potential Relationship between Season of Birth and Clinical Characteristics in Major Depressive Disorder in Koreans: Results from the CRESCEND Study.
abstract: We aimed to examine the potential relationship between season of birth (SOB) and clinical characteristics in Korean patients with unipolar non-psychotic major depressive disorder (MDD). Using data from the Clinical Research Center for Depression (CRESCEND) study in South Korea, 891 MDD patients were divided into two groups, those born in spring/summer (n=457) and those born in autumn/winter (n=434). Measurement tools comprising the Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, Brief Psychiatric Rating Scale, Scale for Suicidal Ideation, Clinical Global Impression of severity, Social and Occupation Functional Assessment Scale, WHO Quality of Life assessment instrument-abbreviated version, Alcohol Use Disorder Identification Test, and Temperament and Character Inventory were used to evaluate depression, anxiety, overall symptoms, suicidal ideation, global severity, social function, quality of life, drinking, and temperament and character, respectively. Using independent t-tests for continuous variables and χ² tests for discrete variables, the clinical characteristics of the two groups were compared. MDD patients born in spring/summer were on average younger at onset of first depressive episode (t=2.084, p=0.038), had greater loss of concentration (χ²=4.589, p=0.032), and were more self-directed (t=2.256, p=0.025) than those born in autumn/winter. Clinically, there was a trend for the MDD patients born in spring/summer to display the contradictory characteristics of more severe clinical course and less illness burden; this may have been partly due to a paradoxical effect of the 5-HT system.
authors.affiliation: Department of Psychiatry, Inje University Haeundae Paik Hospital, Busan, Korea.
authors.forename: Seon-Cheol
authors.initials: SC
authors.lastname: Park
authors.affiliation: Department of Psychiatry, Dongguk University Gyeongju Hospital, Gyeongju, Korea.
authors.forename: Jeong-Kyu
authors.initials: JK
authors.lastname: Sakong
authors.affiliation: Department of Psychiatry, Yeungnam University School of Medicine, Daegu, Korea.
authors.forename: Bon Hoon
authors.initials: BH
authors.lastname: Koo
authors.affiliation: Department of Psychiatry, Chonnam National University School of Medicine, Gwangju, Korea.
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul, Korea.
authors.forename: Tae-Youn
authors.initials: TY
authors.lastname: Jun
authors.affiliation: Department of Psychiatry, Korea University College of Medicine, Seoul, Korea.
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Jung-Bum
authors.initials: JB
authors.lastname: Kim
authors.affiliation: Department of Preventive Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea.
authors.forename: Hyeon-Woo
authors.initials: HW
authors.lastname: Yim
authors.affiliation: Department of Psychiatry, Hanyang University Guri Hospital, Guri, Korea. hypyc@hanyang.ac.kr.
authors.forename: Yong Chon
authors.initials: YC
authors.lastname: Park
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000428:Alcohol Drinking; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000208:ethnology* / Q000523:psychology; D002605:Character; D017281:Cost of Illness; D003863:Depression; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000208:ethnology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010555:Personality Inventory / Q000706:statistics & numerical data; D011788:Quality of Life; D056910:Republic of Korea / Q000453:epidemiology; D012621:Seasons; D013694:Temperament
keywords: Season of birth (SOB); age at onset; diminished concentration; major depressive disorder (MDD); self-directedness