خلق و خو و پروفایل های شخصیت دانشجویان دانشگاه ژاپنی با قسمت و ایده های خودکشی یا افسردگی خودآسیبی: مطالعه غربالگری PHQ-9

Abstract Objective The aim of our study was to reveal the personality traits of individuals with major and other depressive episodes among the young adult population. Furthermore, character traits of individuals with ideas of suicide or self-harm were also investigated in this study. Methods The subjects of this study were 1421 university students who completed the Patient Health Questionnaire (PHQ-9) and the Temperament and Character Inventory (TCI). The subjects were divided into three separate groups: the major depressive episode group (N = 41), the other depressive episode group (N = 97), and the non-depressive controls (N = 1283). This separation was achieved using the PHQ-9 algorithm diagnosis. We compared the TCI scores using an analysis of variance. Moreover, the Cochran-Armitage trend test was used to determine the diagnosis, ideas of suicide or self-harm, and analysis of character profiles.

. Introduction Kessler et al. reported that the highest risk of initial suicide ideation, planning, and attempts took place during an individual's late teens to early 20s [1]. Accordingly, it is very important to study depression and ideas of suicide or self-harm in young adults to prevent suicide. Several studies have examined the pathogenic and predictive role of personality in depressive symptoms among the young adult population using the Temperament and Character Inventory (TCI) [2], [3], [4] and [5]. The TCI is a widely used self-rating scale for assessing personality among adult samples. The TCI consists of four dimensions of temperament [i.e., novelty seeking (NS), harm avoidance (HA), reward dependence (RD), and persistence (P)] and three dimensions of character [i.e., self-directedness (SD), cooperativeness (C), and self-transcendence (ST)]. Among the four temperament dimensions, high HA scores were consistently associated with depressive symptoms in both clinical samples and general populations [6]. Recently, Kampman et al. reviewed 12 studies that focused on the relationship between TCI temperament dimensions and depressive symptoms. He concluded that high HA scores were associated with both current depressive symptoms and a depressive trait [6]. Four recent studies, comprised of young adult participants, also demonstrated the correlation between depressive symptoms and HA scores [2], [3], [4] and [5]. In these studies, the Beck Depression Inventory (BDI), Self-Rating Depression Scale (SDS), and the Hospital Anxiety and Depression Scale (HADS) were used to evaluate depressive symptoms. These instruments can be used as continuous measures of depression severity, but they cannot make a criteria-based diagnosis of depression. Therefore, it is difficult to differentiate threshold and sub-threshold depressive episodes, i.e., major and minor depressive episodes, using the BDI, SDS, and HADS. Hence, these previous studies did not properly judge the temperaments of individuals with major depressive episodes among the young adult population. Moreover, the relationship between minor depressive disorder and personality has yet to be reported. Although minor depressive disorder is thought to be a risk factor for developing major depressive disorder [7], [8] and [9], the personality traits of minor depressive disorder have not been made clear. Concerning character profiles, several previous studies conducted in clinical settings [10] and [11] have reported that depressive symptoms are associated with character immaturity. This character immaturity was indicated by the presence of low SD and low C scores [12]. In a general adult sample, depressive symptoms are often observed in individuals who have an immature character profile [13]. Moreover, a low SD score was suggested as one of the predictors of vulnerability to a future major depressive disorder [14]. Focusing on the young adult population, previous studies reported that SD scores are negatively correlated with depressive symptoms [2], [3], [4] and [5]. The other character dimensions, C [2], [3] and [4] and ST [2], are also negatively correlated with depressive symptoms. Cloninger et al. proposed eight character profiles based on eight possible configurations of high or low scores of SD, C, and ST [15]. For example, the character profile that includes low scores in three different character dimensions will most likely embody a depressive personality. The melancholic character profile is the most common in depression [15]. Although the link between character immaturity and depression is anticipated among the young adult population, the prevalence of depressive episodes among young adults who fit one of Cloninger's eight character profiles has not yet been reported. Another reason for major depressive episode screening among the general population is the early detection of individuals with a high suicide risk. Few studies, at least among the young adult population, have analyzed the association between personality and ideas of suicide or self-harm. According to clinical studies, individuals who had previously attempted suicide [16] and [17] and had suicidal thoughts, [16] along with depression, showed high HA scores and low SD scores. Our recent study demonstrated that young adults who completed suicide consistently had high HA scores [18]. The association between ideas of suicide or self-harm and character profiles has not yet been studied among the young adult population. This study aims to verify a number of hypotheses regarding young adults. First, young adults with major depressive episodes have higher HA scores and lower SD scores than did non-depressive controls. Second, young adults with other depressive episodes defined by the PHQ-9 also have higher HA scores and lower SD scores than non-depressive controls. Third, major or other depressive episodes are more often observed in individuals with low SD scores and low C character profiles than those with high SD scores and high C character profiles. Fourth, ideas of suicide or self-harm are more often observed in individuals with low SD scores and low C character profiles than those with high SD scores and high C character profiles. To screen for major and other depressive episodes and ideas of suicide or self-harm and to study the relationship between these disorders and personality, we administered the PHQ-9, a self-report questionnaire, and TCI to university students. Though the PHQ-9 requires less than 1 minute for patients to complete, it is as good a screener for major depression as longer instruments in various settings, countries, and populations, and has a validity for measuring its severity [19], [20] and [21].

3. Results 3.1. Demographic data Demographic data were shown in Table 1. The ratio of male to female individuals was not significantly different between groups (χ2 = 3.398, P = 0.138). The ANOVA showed no significant difference in mean age between female groups (F = 1.008, P = 0.366) and male groups (F = 0.792, P = 0.453). Meanwhile, as expected, the ANOVA showed significant differences in PHQ-9 total scores between female groups (F = 388.3, P < 0.001) and male groups (F = 673.3, P < 0.001). 3.2. TCI scores Mean TCI scores are shown in Table 2. Concerning interaction effects between gender and diagnosis, we performed a two-way ANOVA test (diagnosis × gender) (Table 3). The results of ANOVA revealed significant effects of diagnosis on HA scores (F[2,1415] = 20.389, P < 0.001), RD scores (F[2,1415] = 10.051, P < 0.001), SD scores (F[2,1415] = 55.108, P < 0.001), and C scores (F[2,1415] = 16.292, P < 0.001). Gender was also shown to have an effect on RD scores (F[1,1415] = 14.089, P < 0.001). No interaction effect, however, was found between gender and diagnosis when analyzing TCI scores ( Table 3). We then performed a post-hoc analysis using the HSD test. No significant difference in TCI scores was found between major depressive episodes and other depressive episode groups. The major depressive episode group had significantly higher HA scores (P < 0.001), lower RD scores (P < 0.001), lower SD scores (P < 0.001), and lower C scores (P < 0.001) than did non-depressive controls. The other depressive episode group had significantly higher HA scores (P < 0.001) and lower SD scores (P < 0.001) than did the non-depressive controls. Table 2. Comparison of TCI scores among non-depressive controls (NC), other depressive episode group (Other) and major depressive episode group (Major). NC (N = 1283) Other (N = 97) Major (N = 41) Female Male Female Male Female Male (N = 377) (N = 906) (N = 36) (N = 61) (N = 15) (N = 26) Mean (S.D.) Mean (S.D.) Mean (S.D.) Mean (S.D.) Mean (S.D.) Mean (S.D.) Temperament NS 49.5 (6.7) 49.8 (6.4) 52.3 (8.5) 49.9 (7.0) 50.1 (5.7) 51.7 (6.9) HA 55.3 (9.4) 55.4 (9.0) 57.7 (11.1) 61.1 (9.9) 63.7 (5.2) 62.5 (7.7) RD 45.6 (5.6) 43.2 (5.5) 45.5 (5.9) 41.5 (6.2) 41.3 (6.8) 39.4 (8.6) P 10.8 (2.7) 10.3 (2.8) 9.9 (3.2) 10.2 (2.9) 11.1 (3.9) 9.7 (4.0) Character SD 89.2 (9.0) 86.7 (9.7) 79.5 (11.2) 78.0 (8.8) 77.8 (10.0) 78.3 (12.3) C 75.4 (7.7) 72.9 (7.8) 74.1 (7.6) 69.4 (8.5) 68.1 (10.0) 66.9 (11.8) ST 15.1 (6.8) 14.2 (6.9) 17.9 (6.9) 13.2 (8.1) 16.2 (6.8) 13.1 (8.1) NS; Novelty Seeking, HA; Harm Avoidance, RD; Reward Dependence, P; Persistence, SD; Self-Directedness, C; Cooperativeness, ST; Self-Transcendence. Table options Table 3. Comparison of TCI scores using a two-way ANOVA. Source of variations F statistic P Tukey HSD test Major vs. Other Major vs. NC Other vs. NC NS Gender 0.033 0.855 Diagnosis 2.532 0.080 - - - Gender × diagnosis 1.869 0.155 HA Gender 0.400 0.527 Diagnosis 20.389 <0.001⁎ 0.168 <0.001↑⁎ <0.001↑⁎ Gender × diagnosis 1.566 0.209 RD Gender 14.089 <0.001⁎ (Female > Male) Diagnosis 10.051 <0.001⁎ 0.015 <0.001↓⁎ 0.307 Gender × diagnosis 0.906 0.404 P Gender 2.044 0.153 Diagnosis 1.105 0.332 - - - Gender × diagnosis 1.236 0.291 SD Gender 0.859 0.354 Diagnosis 55.108 <0.001⁎ 0.966 <0.001↓⁎ <0.001↓⁎ Gender × diagnosis 0.517 0.596 C Gender 7.349 0.007 Diagnosis 16.292 <0.001⁎ 0.029 <0.001↓⁎ 0.006 Gender × diagnosis 0.940 0.391 ST Gender 10.039 0.002 Diagnosis 0.644 0.526 - - - Gender × diagnosis 3.429 0.033 Major; Major depressive episode group, Other; Other depressive episode group, NC; Non-depressive controls, NS; Novelty Seeking, HA; Harm Avoidance, RD; Reward Dependence, P; Persistence, SD; Self-Directedness, C; Cooperativeness, ST; Self-Transcendence. ↑, higher in major or other depressive groups than in NC. ↓, lower in major or other depressive groups than in NC. ⁎ Statistically significant. Table options 3.3. Character profiles of major and other depressive episodes and ideas of suicide or self-harm A logistic regression analysis revealed that SD had the greatest contribution to major and other depressive episodes, followed by C (Table 4). ST did not contribute to major or other depressive episodes significantly. We compared the prevalence of major and other depressive episodes among four categories of possible combinations, which were sc (sct, scT), sC (sCt, sCT), Sc (Sct, ScT), and SC (SCt, SCT). The major or other depressive episodes were observed frequently (16.1%) in individuals who were depressive (sct) or disorganized (scT). Alternately, these episodes were rarely observed (2.2%) in individuals who were creative (SCT) or organized (SCt) (Table 5). The Cochran-Armitage trend test revealed that the prevalence of depressive episodes increased as SD and C scores lowered, i.e., character profiles became immature (χ2trend = 57.2, P < 0.0001). The same tendency was also observed for ideas of suicide or self-harm (χ2trend = 49.3, P < 0.0001) ( Table 6). Table 4. Logistic regression analysis to confirm the effect size of character dimensions. SE Wald OR P 95% C.I. SD 0.011 53.681 1.086 0.000 1.062–1.110 C 0.013 9.264 1.041 0.002 1.014–1.069 ST 0.014 2.978 0.976 0.084 0.949–1.003 SE, Standard error, OR, Odds ratio, C.I., Confidence interval. Table options Table 5. Major or other depressive episode and character profiles. Character profiles Non-depressive controls Major or other depressive episode Total % sc sct Depressive 396 76 472 16.1% scT Disorganized sC sCt sCT Dependent Moody 210 37 247 15.0% Sc Sct ScT Autocratic Fanatical 252 14 266 5.3% SC SCt SCT Organized Creative 394 9 403 2.2% Cochran-Armitage trend test; χ2trend = 57.2, P < 0.0001, χ2linearity = 3.83, P = 0.28. Table options Table 6. Ideas of suicide or self-harm and character profiles. Character profiles No. of subjects without ideas of suicide or self-harm No. of subjects with ideas of suicide or self-harm Total % of ideas of suicide or self-harm sc sct Depressive 406 66 472 14.0% scT Disorganized sC sCt Dependent 221 26 247 10.5% sCT Moody Sc Sct Autocratic 253 13 266 4.9% ScT Fanatical SC SCt Organized 396 7 403 1.7% SCT Creative Cochran-Armitage trend test; χ2trend = 49.3, P < 0.0001, χ2linearity = 0.41, P = 0.94.