اختلالات شخصیتی افزایش یافته و محور همبودی در افسردگی غیر معمولی

Abstract Objective Comparison of patients with and without atypical depression on comorbid Axis I and I disorders to determine whether atypical depression is associated with a higher comorbidity. Method Twenty-nine major depressive disorder patients with and without atypical depression were compared on clinical measures using multiple regression analyses. Results Atypical depression predicted the presence of comorbid Axis I (100% vs 33%), Axis II (90% vs 35%), and both Axis I and II (65% vs 8.14%) disorders. Personality disorders did not mediate the relationship between atypical depression and Axis I comorbidity. Conclusions The high prevalence of Axis I and II comorbidity in major depression may be explained, at least in part, by the presence of atypical depression. Our findings also suggest that the increased Axis I comorbidity observed in atypical depression is independent of the effects of personality disorders and is probably a direct effect of atypical depression subtype. Future research should confirm whether clinical findings associated with atypical depression are independent of their association with personality disorders in a larger sample of depressed patients and also examine treatment implications in atypical depression other than a preferential monoamine oxidase inhibitor responsivity.

. Introduction Atypical depression, a recent subtype of the mood disorders, is defined as mood reactivity and at least 2 of 4 associated features including hyperphagia, hypersomnia, leaden paralysis, and rejection sensitivity [1]. Belying its name, it appears to be a common form of depression with figures ranging from 22% to 83% [2], [3], [4], [5] and [6]. However, studies using a specifically designed scale to diagnose atypical depression (Atypical Depressive Disorder Scale [ADDS] [1]) report rates between 30% and 46% [2], [3] and [4]. Consistent with earliest conceptualizations of atypical depression [1], recent reports have observed a primacy of the personality style descriptor of rejection sensitivity over the other features [1], [5], [6] and [7]. A number of findings further underscore the importance of personality features in atypical depression. Researchers have observed that atypical depression is chronic, associated with a younger age of onset and a longer duration of illness [2]. In addition, some recent studies have observed high rates of some personality dimensions in atypical depression [4], [5], [6], [7], [8], [9] and [10]. However, given that major depression in general is associated with high rates of personality disorders [11], it is important to determine whether personality disorders are differentially elevated in atypical depression. One recent study found higher rates of personality disorders in patients exhibiting atypical features [5]. However, threshold levels necessary to diagnose atypical depression were not established. Instead, atypical features were assessed retrospectively using a comprehensive general psychiatric measure (Structured Clinical Interview for the DSM-IV [SCID]), which, in contrast to the ADDS, does not include the necessary anchor points for each symptom to prospectively diagnose atypical depression [1]. For example, mood reactivity, a required criterion, is diagnosed as present in the SCID if patients state that they feel better when something good happens without specifying the extent of improvement; the Columbia Group clearly states that there must be at least 50% improvement in mood which is elicited by the ADDS [1]. Using a structured assessment measure to prospectively diagnose atypical depression, this preliminary study compared patients with and without atypical depression on DSM-IV personality disorders. Given the posited link between atypical depression and personality, we predicted that patients with atypical depression would exhibit a higher prevalence of personality disorders than those without atypical depression. Given the high levels of Axis I comorbidity observed in major depression [12], recent findings of higher lifetime comorbidity of some Axis I disorders in patients exhibiting atypical features [5], as well as recent findings that patients with atypical depression may be more symptomatic than those without the subtype [5], [13] and [14], we also hypothesized that atypical depression would be associated with a higher current prevalence of comorbid Axis I disorders. Because personality disorders have been associated with higher Axis I comorbidity in general [15], we wanted to determine whether the increased Axis I comorbidity in atypical depression would be independent of its association with personality disorders. We hypothesized that the association between atypical depression and comorbid Axis I disorders would be mediated by the presence of personality disorders.

3. Results 3.1. Overall sample Mean (M) scores placed our overall sample in the moderate range of depression (BDI: M = 28.3, SD = 10.61; HAM-D: M = 23.17, SD = 6.74). Sixty-three percent of the overall sample of patients with major depression were diagnosed with one or more Axis II disorders, whereas 65% were diagnosed with one or more comorbid Axis I disorders. The correlation between Axis II comorbidity and the extended HAM-D was significant (r = .56, P < .01), suggesting that patients with higher severity of illness on the Extended HAM-D (which takes into account atypical symptomatology) were more likely to have one or more Axis II disorders. The correlations between Axis II comorbidity and both the BDI and the 17-item HAM-D were not significant. Correlations between Axis I comorbidity and severity of illness on the BDI and both versions of the HAM-D were also not significant. 3.2. Atypical (AD) vs nonatypical depression (non-AD) 3.2.1. Demographic variables Forty-six percent (n = 12) of MDD patients met criteria for AD, with rejection sensitivity being the most frequently associated symptom (92%). Table 1 presents demographic variable for the entire sample and for patients with and without AD. Patients with and without AD did not show significant differences in age, sex, race, marital status, educational, or occupational status (Table 1). The 2 groups did not exhibit significant differences either on duration of illness, duration of current episode, age at onset of illness, previous treatments or hospitalizations (Table 1). However, nonsignificant trends revealed that patients with AD were more likely to have an earlier age of onset, longer duration of current episode, longer duration of illness, and to have been hospitalized than patients without AD. Table 1. Sample demographics Total sample (n = 29) Atypical depression (n = 12) Nonatypical depression (n = 17) t (df) or χ2 (df) P Age 39.55 (10.67) 38.25 (8.97) 42.13 (11.67) t = 0.492 (23) .627 Sex: females (%) 68 75 66.7 χ2 = 0.22 (1.0) .637 Race (%) χ2 = 4.57 (3.0) .207 White 27.6 16.7 40.0 Hispanic 48.3 66.7 33.3 Black 13.8 8.3 20.0 Other 6.9 8.3 0 Marital status χ2 = 2.15 (3.0) .543 Single 37.9 41.7 33.9 Married 24.1 33.3 20.0 Separated/divorced 27.6 25.0 26.7 Widowed 6.9 6.7 Educational status χ2 = 1.78 (3.0) .62 No HS 24.1 33.3 13.3 GED 34.5 41.7 26.7 HS 20.7 16.7 26.7 College 10.3 8.3 13.3 Occupational status, % unemployed 31% 25% 26.7% χ2 = 3.64 (6.0) .725 Duration of current episode (wk) 5.14 (5.69) 6.11 (7.56) 4.0 (3.4) t = −0.78 (15) .449 Duration of illness (wk) 111.09 (109.45) 124.0 (129) 99.55 (96.31) t = −0.59 (18) .559 Age at onset of illness (y) 28.83 (12.06) 26.18 (9.78) 32.09 (14.15) t = 0.79 (18) .442 Previous treatment, % treated 34.78 36.36 33.33 χ2 = .02 (1) .879 Previous hospitalizations (%) 26.09 50.0 15.38 χ2 = 1.78 (1) .183 Table options 3.2.2. Axis I and II comorbidity As predicted, patients with AD were more likely to have one or more Axis II disorders than patients without AD (Table 2). Ninety percent of patients with AD met criteria for at least one or more Axis II disorders. In contrast, only 35% of patients without AD met criteria for a personality disorder. As hypothesized, patients with AD were also significantly more likely than those without the subtype to be diagnosed with one or more comorbid Axis I disorders (Table 2). A hundred percent of patients with AD met criteria for one or more comorbid Axis I disorders as compared to only 33% of patients without AD who met the same. Patients with AD were also more likely than patients without AD to have both Axis I and II comorbidity (AD = 67%; non-AD = 7.14%). Table 2. Clinician measures: Axis I and Axis II disorders in patients with and without atypical depression Presence of one or more comorbid Axis I disorders (%) Presence of one or more Axis II disorders (%) Percent of variance accounted for (%) Standardized β P Atypical 100 90 43.2 .66 <.001 Nonatypical 33.3 35 23.4 .49 <.01 Table options Categorization of depression accounted for 43.2% of the variance in Axis I comorbidity (standardized β = .66, P < .001), 23.4% of the variance in the presence of Axis II disorders (standardized β = .49, P < .01), and 27.9% of the variance in the presence of both Axis I and II disorders (standardized β = .61, P < .008). Specifically, multiple regression analyses revealed that the presence of AD predicted the presence of personality disorders and comorbid Axis I disorders as well as the combined presence of both comorbid Axis I and II disorders. However, mediational analyses were not possible because comorbid Axis I and II disorders were not correlated. Based on the Baron and Kenny [24] formulation of mediational modeling, mediation is not possible when all 3 variables are not correlated with each other. Exploratory t tests were computed to assess the difference between patients with and without AD on related anxiety and depression inventories. Means for each of the 2 groups are presented in Table 3. Although differences between the 2 groups were not significant, a trend was observed for patients with AD to exhibit greater pathology on the extended version of the HAM-D scale and the Beck Anxiety Inventory. Table 3. Self-report measures: differences in severity of illness and personality symptoms between patients with atypical and nonatypical depression Atypical, M (SD) Nonatypical, M (SD) t (df) P Extended HAM-D 37.10 (5.88) 31.08 (9.74) −1.70(21) .10 17-Item HAM-D 23.7 (6.55) 22.92 (7.35) −.26 (21) .79 BDI 28.75 (10.66) 27.0 (11.56) −.33 (16) .75 Beck Anxiety Inventory 33.2 (12.71) 28.36 (10.85) −.94 (19) .36 Beck Scale for Suicidal Ideation 2.88 (6.08) 5.10 (8.65) .62 (16) .55 Beck Hopelessness Scale 11.40 (6.22) 12.36 (5.70) .37 (19) .72