Personality traits spectrum in panic disorder and major depression

O espectro de traços de personalidade no transtorno do pânico e na depressão maior

Abstracts

OBJECTIVE: Our aim was to identify the personality traits in patients with panics disorder, major depression and with both disorders (comorbidity). METHOD: Diagnoses were made with the Structured Clinical Interview for DSM-IV before the treatment, and the personality evaluation with the Maudsley Personality Inventory was made during the follow-up. Four groups were analyzed: a control group (n = 30), a major depression without panic disorder group (n = 45); a panic disorder without major depression group (n = 56) and a comorbidity group (n = 21), with major depression and panic disorder, simultaneously. RESULTS: All disorder groups had significantly higher neuroticism means when compared to the control group. The highest mean was in the comorbidity group, followed by the major depression group and the panic disorder group. The difference of neuroticism means between the comorbidity group and the panic disorder group also reached statistical significance. The lowest extraversion mean was in the comorbidity group, followed by the major depression group, the panic disorder group, and the control group. Compared to normal controls, extraversion was significantly low in the comorbidity and major depression groups. CONCLUSION: In our sample, there was a continuum of personality traits between panic disorder and major depression and, the co-occurrence of these disorders was associated with accentuated personality traits.

Anxiety disorders; Mood disorders; Personality; Panic disorder; Depressive disorder

ORIGINAL ARTICLE

Personality traits spectrum in panic disorder and major depression

O espectro de traços de personalidade no transtorno do pânico e na depressão maior

Rafael C Freire; Fabiana L Lopes; André B Veras; Alexandre M Valença; Marco A Mezzasalma; Isabella Nascimento; Antonio E Nardi

Laboratory of Panic and Respiration, Institute of Psychiatry, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (RJ), Brazil

^{Correspondence}

ABSTRACT

OBJECTIVE: Our aim was to identify the personality traits in patients with panic disorder, major depression and with both disorders (comorbidity).

METHOD: Diagnoses were made with the Structured Clinical Interview for DSM-IV before the treatment, and the personality evaluation with the Maudsley Personality Inventory was made during the follow-up. Four groups were analyzed: a control group (n = 30), a major depression without panic disorder group (n = 45); a panic disorder without major depression group (n = 56) and a comorbidity group (n = 21), with major depression and panic disorder, simultaneously.

RESULTS: All disorder groups had significantly higher neuroticism means when compared to the control group. The highest mean was in the comorbidity group, followed by the major depression group and the panic disorder group. The difference of neuroticism means between the comorbidity group and the panic disorder group also reached statistical significance. The lowest extraversion mean was in the comorbidity group, followed by the major depression group, the panic disorder group, and the control group. Compared to normal controls, extraversion was significantly low in the comorbidity and major depression groups.

CONCLUSION: In our sample, there was a continuum of personality traits between panic disorder and major depression and, the co-occurrence of these disorders was associated with accentuated personality traits.

Descriptors: Anxiety disorders; Mood disorders; Personality; Panic disorder; Depressive disorder

RESUMO

OBJETIVO: Identificar os traços de personalidade presentes em pacientes com transtorno do pânico, depressão maior e comorbidade.

MÉTODO: Os diagnósticos foram feitos com o Structured Clinical Interview para o DSM-IV antes do início do tratamento, e a avaliação dos traços de personalidade com o Maudsley Personality Inventory foi feita durante o acompanhamento desses pacientes. Quatro grupos foram comparados: um grupo controle (n = 30), um grupo de depressão maior sem transtorno do pânico (n = 45); um grupo de transtorno do pânico sem depressão maior (n = 56) e um grupo de comorbidade (n = 21), com transtorno do pânico e depressão maior, simultaneamente.

RESULTADOS: Todos os grupos de pacientes tiveram médias de neuroticismo significativamente maiores quando comparados ao grupo controle. A maior média foi no grupo de comorbidade, seguida pelas dos grupos de depressão maior e transtorno do pânico. A diferença de neuroticismo entre o grupo de comorbidade e de transtorno do pânico também foi estatisticamente significativa. Entre os grupos de pacientes, a menor média de extroversão foi a do grupo de comorbidade, seguida pelas de depressão maior e transtorno do pânico. Quando comparados ao grupo controle, apenas os grupos de comorbidade e depressão maior tiveram extroversão significativamente mais baixa.

CONCLUSÃO: Na nossa amostra, houve uma continuidade de traços de personalidade entre o transtorno do pânico e a depressão maior, e a sobreposição de sintomas de pânico-agorafobia e de depressão estava associada a traços de personalidade acentuados.

Descritores: Transtornos da ansiedade; Transtornos do humor; Personalidade; Transtorno de pânico; Transtorno depressivo

Introduction

The current categorical systems for psychiatric diagnosis fail to capture the continuum between the core symptoms and the prodromal, atypical and residual psychopathology, as well as temperament and personality traits.¹ Personality and temperament are frequently presented as chronic subthreshold symptomatology, and seem to be close to the underlying biological diatheses of mood and anxiety disorders.^2-3 Tyrer identified a continuum between depression symptoms in one extreme and anxiety symptoms in the other and called this the general neurotic syndrome.^4-5 In contrast, Cassano hypothesized that different disorders have different spectra, and each spectrum would respond better to a specific treatment.¹

According to Clark et al., there are several models for understanding the relationship between personality and distress disorders, such as panic disorder and depression.⁶ The predisposition and vulnerability model explains personality traits as an etiological factor for the development of a distress disorder. These traits may provide a general predisposition to a wide range of disorders, to a particular disorder or even to a disorder subtype.⁶ The second model is the pathoplasty model, in which the personality characteristics influence the course and intensity of a distress disorder, although without a causal role.⁶ The scar hypothesis postulates that an anxiety or mood disturbance provokes an enduring modification on personality. The last model is the spectrum of continuity hypothesis, in which personality and distress disorders are considered as epiphenomena of an underlying process. According to this model, the relationship between major symptoms, lower order symptoms and personality traits is not hierarchical.⁶ Besides, a number of studies indicated that the neuroticism and extraversion measures might be influenced by the psychiatric state.⁷ The personality measures may reflect current distress disorders, in addition to long-standing personality.⁷

In a review study, Enns and Cox found a strong association between depression and neuroticism. Some studies also found that low extraversion is associated with depression.⁷ However, effects of extraversion are less robust than comparable findings for neuroticism.⁷ Searching the relationship between normal personality traits and DSM-IV axis I disorders, Bienvenu et al. found that high neuroticism was associated with agoraphobia, panic disorder and major depression.⁸ Introversion was related to agoraphobia, but unrelated to panic disorder or major depression. Other personality factors as openness, agreeableness and conscientiousness failed to show statistically significant differences, compared to healthy controls. In another study,⁹ with a nation-wide representative sample of 5,877 subjects, it was found that high neuroticism might increase the risk for depression.

The objective of this study was to identify the personality traits in patients with panic disorder or major depression. In patients with overlapping panic-agoraphobic and depression symptoms, we expected to find more marked personality traits. High neuroticism should be found in all groups, and low extraversion in the major depression groups.

Method

This is a cross-sectional study of patients currently under treatment in the Laboratory of Panic and Respiration of the Institute of Psychiatry, Universidade Federal do Rio de Janeiro, Brazil. Patients with major depression or panic disorder examined between January, 2002, and June, 2005, were invited to participate in this study.

The exclusion criteria were: unstable medical condition, pregnancy or the presence of suicidal risk. Patients who met DSM-IV¹⁰ criteria for bipolar disorder, schizophrenia, delusional or psychotic disorders, organic brain syndrome, severe personality disorder, epilepsy, substance abuse or dependence (during the previous year), were excluded.

Diagnoses were made with the Structured Clinical Interview (SCID-I) for DSM-IV¹¹ before the treatment. Two psychiatrists from the medical staff applied the instrument. The personality traits evaluation was made within the first follow-up month, during the acute phase of the disorders. The sample filled the Maudsley Personality Inventory.¹² This is a self-rated questionnaire created by Hans Eysenck, and it is used to assess normal personality traits such as neuroticism and extraversion. Neuroticism is considered a temperamental sensitivity to negative stimuli, leading to fear, anxiety, depression, guilt and self-dissatisfaction. Extraversion is related to positive emotionality, energy, affiliation, sociability and dominance. There is also a lying score, which is a tool to measure how sincerely people answer the questionnaire.

In order to participate in the study, the subjects should age 18 to 65 years and not have any clinical medical condition that could influence the complaints profile. All the patients were capable of reading and writing without difficulty. Our local Ethics Committee approved the protocol for this study (process n. 0008.0.249.000-05).

We also recruited students and administrative staff from the university to constitute a control group. Subjects were screened with the SCID for DSM-IV,¹¹ and those who met criteria for any axis I psychiatric disorder were excluded. Those who received psychiatric treatment at any moment in the course of their lifetime, as well as those who used psychotropic drugs in the last three months, were also excluded.

A sample of 122 patients and a control group of 30 people were selected. The mean age for the whole sample was 38.5 years (S.D. ± 11.7), 111 females and 41 males. Four groups were analyzed: a major depression without panic disorder group (n = 45); a panic disorder without major depression group (n = 56) and a comorbidity group (n = 21), with major depression and panic disorder, simultaneously as well as the control group (n = 30).

1. Statistical analysis

To determine which variables influenced the scores, multiple linear regression (MLR) was used. When comparing the groups, our data failed in the normality tests, so the statistical analysis was made with the Kruskal-Wallis One Way Analysis of Variance on Ranks. Multiple pairwise comparisons, with Dunn's method, were made between all the four groups, regarding neuroticism, extraversion and the lying score. All p values were two- tailed, and statistical significance was set at 5% level (p < .05).

Results

The mean age in the control group was 31.2 years, lower than the means of the disorder groups, which was around 43 years (Table 1). In all groups there were more females than males (Table 1).

Besides the group influence (p = 0.005), female gender (p = 0.031) predicted higher neuroticism scores in the multiple linear regression analysis (MLR). Group and gender did not influence extraversion scores; however, higher age (p < 0.001) predicted lower extraversion scores. These MLR results should be cautiously examined because, even after a transformation in ranks, our data did not show a normal distribution.

The differences in the means for neuroticism between the groups were greater than would be expected by chance (H = 31.253; 3 df; p < 0.001). The MD group (Q = 4.187; p < 0.05), the PD group (Q = 3.510; p < 0.05), and the comorbid MD and PD group (Q = 5.274; p < 0.05) had significantly higher neuroticism means compared to the control group. The comorbidity group had the highest mean, followed by the MD group and the PD group. The difference of neuroticism means between the comorbidity group and the panic disorder group was also statistically significant (Q = 2.761; p < 0.05) - Table 1.

Regarding extraversion, there was also a statistical difference between groups (H = 11.697; 3 df; p = 0.008). The comorbidity group had the lowest extraversion mean, followed by the major depression group and the panic disorder group. In multiple comparisons, only the comorbidity (Q = 3.048; p < 0.05) and the major depression (Q = 2.689; p < 0.05) groups reached a significant difference compared to the control group. There were no significant differences in lying score means (Table 1).

Discussion

Compared to the healthy controls, the disorder groups had higher neuroticism scores. The comorbidity group had the higher means for neuroticism, approximately 1.5 standard deviations above the control group. Except for the panic disorder group, all the other patient groups were more introverted.

Bienvenu et al. also found high neuroticism means for all the disorder groups. Low extraversion was associated with agoraphobia, but not with depression, as it was found in our study.⁸ In both studies introversion was not associated with panic disorder. In another study,¹³ neuroticism, low extraversion, low age and female gender were associated with higher prevalence of psychiatric disorders. These factors were related to higher comorbidity among depressive and anxiety disorders. It was also found that extraversion increased the risk for comorbidity, but these findings were not replicated in other studies. Reich et al. found no personality differences between panic and depressed patients.¹⁴ The "state" effect on personality measures was similar for PD and MD.¹⁴ Foot & Koszycki examined the gender differences in a group of 101 individuals with panic disorder with or without agoraphobia.¹⁵ No significant differences were found in anxiety sensitivity and neuroticism scores, but women scored higher than men on extraversion. In order to demonstrate these personality differences between panic disorder and major depression, Cox et al. compared two groups of patients with 38 people each.¹⁶ The logistic regression analysis pointed to positive affectivity and autonomic arousal as the more important differences between the two groups. At a lower-order level, anxiety sensitivity and a ruminative response style demonstrated predictive ability. Patients with depression and panic disorder showed higher scores in the Panic-Agoraphobic Spectrum Questionnaire,¹ seemed to have a worse response to treatment, and took longer to achieve remission.¹⁷

In a review made by Clark et al., neuroticism was considered a stable, heritable,

and general personality dimension, which might influence mood and behavior.⁶ The core of this trait is a higher sensitivity to negative stimuli, but there are also negative cognitions, negativistic appraisals of self and others, pessimism, somatic complaints, low self-esteem and life dissatisfaction issues. An aversive motivational system (behavioral inhibition system) would inhibit behavior and stimulate autonomic arousal to protect an individual from harm, but when malfunctioning it would lead to neuroticism. Negative affectivity is broadly associated with a large number of disorders such as panic disorder, specific phobias, social phobia, posttraumatic stress disorder, generalized anxiety disorder and depression. According to the same study,⁶ people with high extraversion measures tend to feel joyful, enthusiastic, energetic, friendly, bold, assertive, proud and confident, while those with low extraversion measures tend to feel dull, flat, disinterested and unenthusiastic, and these feelings would lead to depressive disorders. Some studies indicated that extraversion is related to major depression, and even when depressive symptoms remit, extraversion remains low. In turn, neuroticism is reduced along with the depressive symptoms and with the passing of time.^18-19

There are several studies that are consistent with the theoretical models explaining the relationship between distress disorders and personality traits.⁷ In a longitudinal study in women, Kendler et al. found that high neuroticism predicted the prevalence of MD.²⁰ In patients with current major depression there was a substantial elevation in neuroticism scores, and when there were previous major depression episodes, these scores were moderately increased. However, the direct influence of a major depression episode on neuroticism through "scar" and "state" effects was considered comparatively weak. The authors concluded that neuroticism and MD shared genetic risk factors.²⁰ In a four-year prospective study with 2,365 high school students,²¹ it was found that negative affectivity predicted onset of major depression and panic attacks. Some studies indicate that MD increases the risk of PD and vice versa.^21-23 Some authors suggest that genetic factors predispose to both disorders.^22-23 Our cross-sectional study could not confirm any models proposed by Clark.⁶ However, our data indicated that MD, PD and neuroticism might share a common underlying etiology, possibly a genetic factor.

The main limitations of our study were the difference in the group sizes and the lower mean age in the control group. There was only one personality evaluation during the follow-up, and "state-trait confounding" cannot be ruled out. This study was based on DSM-IV criteria and lacks a more extensive review of spectrum symptoms.

Conclusion

There was an association between low extraversion and depression, while neuroticism was related to both depression and panic disorder. In our sample there was a continuum of personality traits between these disorders, and when depression and panic disorder overlapped, the comorbidity group formed showed very high neuroticism and low extraversion.

Acknowledgments

Supported by the Brazilian Council for Scientific and Technological Development (CNPq).

References

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3. Akiskal HS, Akiskal K. Cyclothymic, hyperthymic and depressive treatments as subaffective variants of mood disorders. In: Tasman A, Riba MB, ed. APA Review. Washington (DC): American Psychiatric Press; 1992. p. 43-62.

4. Tyrer P. Classification of neurosis. New York (NY): John Wiley & Sons; 1989.

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13. Bienvenu OJ, Brown C, Samuels JF, Liang KY, Costa PT, Eaton WW, Nestadt G. Normal Personality Traits and Comorbidity among Phobic, Panic and Major Depressive Disorders. Psychiatry Res. 2001;102(1):73-85.

14. Reich J, Noyes R Jr, Hirschfeld R, Coryell W, O'Gorman T. State and personality in depressed and panic patients. Am J Psychiatry. 1987;144(2):181-7.

15. Foot M, Koszycki D. Gender differences in anxiety-related traits in patients with panic disorder. Depress Anxiety. 2004;20(3):123-30.

16. Cox BJ, Enns MW, Walker JR, Kjernisted K, Pidlubny SR. Psychological Vulnerabilities in Patients with Major Depression vs. Panic Disorder. Behav Res Ther. 2001;39(5):567-73.

17. Frank E, Shear MK, Rucci P, Cyranowski JM, Endicott J, Fagiolini A, Grochocinski VJ, Houck P, Kupfer DJ, Maser JD, Cassano GB. Influence of panic-agoraphobic spectrum symptoms on treatment response in patients with recurrent major depression. Am J Psychiatry. 2000;157(7):1101-7.

18. Liebowitz MR, Stallone F, Dunner DL, Fieve RF. Personality features of patients with primary affective disorder. Acta Psychiat Scand. 1979;60(2):214-24.

19. Hirschfeld RM, Klerman GL. Personality attributes and affective disorders. Am J Psychiatry. 1979;136(1):67-70.

20. Kendler KS, Neale MC, Kessler RC, Heath AC, Eaves LJ. A longitudinal twin study of personality and major depression in women. Arch Gen Psychiatry. 1993;50(11):853-62.

21. Hayward C, Killen JD, Kraemer HC, Taylor CB. Predictors of panic attacks in adolescents. J Am Acad Child Adolesc Psychiatry. 2000;39(2):207-14.

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23. Leckman JF, Merikangas KR, Pauls DL, Prusoff BA, Weissman MM. Anxiety disorders and depression: contradictions between family study data and DSM-III conventions. Am J Psychiatry. 1983;140(7):880-2.

Submitted: February 7, 2006

Accepted: September 4, 2006

Financing: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq - Brazilian Council for Scientific and Technological Development), Grant 470178/03.5

Conflicts of interest: None

Publication Dates

• Publication in this collection
  22 Oct 2006
• Date of issue
  Mar 2007

History

• Accepted
  04 Sept 2006
• Received
  07 Feb 2006