Impulsivity in Euthymic Patients With Major Depressive Disorder The Relation to Sociodemographic and Clinical Properties Okan Ekinci, MD, Yakup Albayrak, MD, and Ali Caykoylu, MD Abstract: The purpose of this study was to examine the trait impulsivity of patients with a major depressive disorder and to explore the possible connec- tions between impulsivity and clinical and sociodemographic variables. The sociodemographic and clinical properties of 60 patients with major depression, who were euthymic according to Hamilton Depression Scale scores, were recorded. Their trait impulsivity was evaluated using the Barratt Impulsiveness Scale (BIS-11) and the impulsivity subscale of the Temperament and Character Inventory, and the results were compared with those of 50 age- and sex- matched healthy controls. We used general linear model analysis to evaluate the manner in which the variables contributed to BIS-11 scores. Some im- pulsivity scores were higher in those with a major depressive disorder than in comparison subjects. There were significant effects of education and sex in these differences. Elevated BIS-11 scores were associated with a history of psychotic mood episode and suicide attempts. These relationships persisted when age, sex, and education were taken into account. These results show that, after accounting for common confounding factors, trait-like impulsivity was substantially higher in subjects with major depressive disorder than in com- parison subjects and may be associated with sociodemographic and clinical properties. Key Words: Major depressive disorder, impulsivity, education, sex, suicide. (J Nerv Ment Dis 2011;199: 454Y458) I mpulsivity is defined as a predisposition toward rapid, unplanned reactions to internal or external stimuli without regard to the negative consequences of these reactions to the impulsive individual or to others. Although impulsivity can be present in any individual with or without a DSM-IV axis I or II diagnosis, it is more likely to be present in individuals with certain psychiatric disorders, such as personality disorders and substance dependence. The association between these disorders and impulsivity is at least partly caused by the manner in which these disorders have been conceptualized, with a lack of be- havioral inhibition being an element of all of these disorders (Moeller et al., 2001). The results of a principal components analysis of the Barratt Impulsiveness Scale suggest a three-factor model of impul- sivity that includes greater motor activation, less attention, and less planning (Patton et al., 1995). Because these three variables have been implicated in impulse control disorders, it is possible that different psychiatric disorders are related to impulsivity through the different patterns of these underlying mechanisms (Moeller et al., 2001; Najt et al., 2007). Impulsivity has been mostly studied in bipolar disorder among the major affective disorders. It is a key component of the manic behavior of bipolar disorder and is increased in bipolar disorder, even when patients are euthymic (Peluso et al., 2007; Swann et al., 2008). Although the relation between impulsivity and depression has been considered as a significant feature, impulsivity has not been widely studied in major depressive patients. To date, the studies examining impulsivity in a major depressive disorder (MDD) have been focused on the association between impulsivity and suicidality. The major limitation of these studies conducted on patients with major depres- sion was that all patients were not euthymic and mood states may affect the results (Lejoyeux et al., 2002; Corruble et al., 2003; Westheide et al., 2007). Furthermore, these studies demonstrated limited and controversial findings about impulsivity and its correlates in patients with MDD. To our knowledge, there is no study that specifically examined the relation between sociodemographic and clinical features and im- pulsivity in patients with MDD. In our study, we used the Barratt Impulsivity Scale (BIS) and Temperament and Character Inventory- impulsivity subscale (TCI-NS2) in patients with euthymic MDD and made it our goal to find the differences between a) patients with MDD and healthy controls and b) depressive patients with different clinical and sociodemographic properties. We examined trait impulsivity in major depressive disorder in relation to demographic characteristics and the course of illness. Our hypothesis was that euthymic patients with MDD would have higher impulsivity scores than healthy subjects and that some clinical and sociodemographic features would be dif- ferentially related to impulsivity in subjects with depression. METHODS Subjects This was a cross-sectional study. A total of 60 euthymic patients who met DSM-IV criteria for MDD and 50 healthy controls participated in the present study (American Psychiatric Association, 2000). The subjects with MDD were recruited from previously hos- pitalized patients in the inpatient unit at the Ankara Ataturk Education and Research Hospital. The study was reviewed and approved by our institutional review board. Before study-specific procedures were carried out, the study was thoroughly explained to the subjects, and written informed consent was obtained. Clinical variables were col- lected through psychiatric interview and through a review of the pa- tient charts and inpatient files. All of the patients were in a state of remission at the time of testing. Remission was defined as a period of at least 2 months during which the subject functioned well (sub- jectively according to the patient and objectively according to his/ her psychiatrist) and the Hamilton Depression Rating Scale (HDRS) scores were below 7. In addition, 50 control subjects matched for age, education, and sex were tested. Inclusion criteria consisted of being 18 to 55 years old and being in remission for two months (HDRS score G7). The subjects who had other disorders that could have an influence on cognitive function (significant neurological and physical illness, substance abuse or dependence in the past year, electrocon- vulsive therapy in the preceding year, and intoxication or cerebral trauma history) and those who had comorbid axis I or II disorders were excluded. The controls were also assessed using BIS, TCI-NS2, and HDRS. Exclusion criteria and the age range of controls were identical to those of patient groups. The control group was comprised ORIGINAL ARTICLE 454 www.jonmd.com The Journal of Nervous and Mental Disease & Volume 199, Number 7, July 2011 Department of Psychiatry, Ataturk Education and Research Hospital, Ankara, Turkey. Send reprint requests to Okan Ekinci, MD, Ankara Ataturk Egitim ve ArastNrma Hastanesi Psikiyatri Klinigi, 06520 Bilkent, Ankara, Turkey. E-mail: drokanekinci@yahoo.com. Copyright * 2011 by Lippincott Williams & Wilkins ISSN: 0022-3018/11/19907-0454 DOI: 10.1097/NMD.0b013e3182214116 Copyright © 2011 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Copyright © 2011 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.