- Email: [email protected]
Personality dimensions in pathological gambling disorder and obsessive–compulsive disorder
Psychiatry Research 104 Ž2001. 205᎐212
Personality dimensions in pathological gambling disorder and obsessive᎐compulsive disorder Suck Won KimU , Jon E. Grant Department of Psychiatry, Uni¨ ersity of Minnesota School of Medicine, F256 r 2A West, 2450 Ri¨ erside A¨ enue, Minneapolis, MN 55454-1495, USA Received 24 February 2001; received in revised form 15 August 2001; accepted 19 September 2001
Abstract This study was conducted to investigate the similarities and differences in the personality dimensions of patients with pathological gambling disorder ŽPGD. and obsessive᎐compulsive disorder ŽOCD.. Thirty-three subjects with PGD, 41 with OCD and 40 normal controls were assessed with the Tridimensional Personality Questionnaire ŽTPQ., which assesses three personality dimensions: novelty seeking, reward dependence, and harm avoidance. Compared with OCD subjects, PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. The PGD subjects also reported significantly less anticipatory worry, fear of uncertainty, and harm avoidance than the OCD subjects. Compared with controls, the PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. These results suggest that the personality dimensions of pathological gamblers may differ significantly from both those of OCD patients and normal controls. 䊚 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Tridimensional Personality Questionnaire; Impulsiveness; Obsessive᎐compulsive disorder
1. Introduction Pathological gambling, a disorder characterized by persistent and recurrent maladaptive patterns of gambling behavior, is classified as an impulse control disorder in DSM-IV, but has been noted to have similarities to obsessive᎐compulsive disorder ŽOCD. ŽMcElroy et al., 1993; Blanco et al., U
Corresponding author. Tel.: q1-612-273-9805; fax: q1612-273-9779. E-mail address: [email protected] ŽS. Won Kim..
2001.. Gambling activities, like OCD compulsions, are often experienced as uncontrollable and anxiety- or tension-relieving, may be resisted, are often followed by self-reproach, and are often denied ŽMcElroy et al., 1994.. Furthermore, treatment data suggest that pathological gambling disorder ŽPGD., like OCD, may respond to serotonin reuptake inhibitors ŽHollander et al., 2000; Kim and Grant, 2001.. There is, however, scant and contradictory literature concerning OCD or OCD traits in subjects with PGD. Two epidemiological studies are
0165-1781r01r$ - see front matter 䊚 2001 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 5 - 1 7 8 1 Ž 0 1 . 0 0 3 2 7 - 4
206
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
inconclusive concerning the rates of comorbid OCD in pathological gamblers. One study failed to find an increased odds ratio for OCD in subjects with PGD ŽCunningham-Williams et al., 1998., whereas the other study concluded that the relative risk for OCD in PGD was 7.2 ŽBland et al., 1993.. One study looking at rates of OCD in a small sample Ž N s 25. of pathological gamblers found that perhaps 20% suffered from comorbid OCD ŽLinden et al., 1986.. Reviewing the literature on OCD traits in pathological gamblers is also inconclusive. One study examining obsessions and compulsions Žusing the Padua Inventory. in subjects with PGD found that pathological gamblers scored significantly higher on obsessive᎐compulsiveness than normal controls, particularly on the element of ‘impaired control over mental activities’ ŽBlaszczynski, 1999.. These results, however, may highlight the obsessionality in pathological gamblers or may simply reflect adequate insight by subjects with PGD concerning their PGD symptoms ŽBlanco et al., 2001.. When assessing rates of comorbid PGD in subjects with OCD, however, the results do not support a strong association between the disorders. A study of 701 subjects with OCD found that less than 1% had a lifetime diagnosis of PGD ŽHollander et al., 1997.. A second study of 80 subjects with OCD found that no one had a current or lifetime diagnosis of PGD ŽBienvenu et al., 2000.. Even studies looking at first-degree relatives of subjects with OCD have found virtually no one who carries a diagnosis of PGD ŽBlack et al., 1994; Bienvenu et al., 2000. Obsessive᎐compulsive disorder and impulsivity may not be mutually exclusive, and impulsivity may instead index a subgroup of subjects with OCD ŽBlanco et al., 2001.. One study found that subjects with OCD and a history of impulsiveness scored higher on the Barratt Impulsiveness Scale than subjects with OCD and no history of impulsiveness ŽHoehn-Saric and Barksdale, 1983.. Supporting the view of OCD subjects as being harm avoidant, however, one study found that subjects with OCD did not score higher than normal controls on the Barratt Impulsiveness Scale ŽStein et al., 1994..
Little has been published on the prevalence of categorical personality disorders in subjects with PGD. A study of 30 subjects with PGD found high rates of obsessive᎐compulsive personality disorder Ž59%., avoidant personality disorder Ž50%., and schizoid and schizotypal personality disorders Ž33 and 30%, respectively. ŽBlack and Moyer, 1998.. One other study found that 93% of a group of subjects seeking gambling treatment met criteria for at least one personality disorder ŽBlaszczynski and Steel, 1998.. This study was conducted to investigate the similarities and differences in the personalities of patients with PGD and OCD. Unlike categorical assessments of personality disorders, the unified biosocial model of personality proposed by Cloninger identifies three heritable personality dimensions, each hypothesized to represent an independent behavioral response disposition ŽCloninger, 1986, 1987.. The Tridimensional Personality Questionnaire ŽTPQ. operationalizes these dimensions: novelty seeking; harm avoidance; and reward dependence. Individuals who score high on the novelty seeking dimension of the TPQ are thought to be impulsive, extravagant and disorderly ŽPfohl et al., 1990; Svrakic et al., 1991.. High avoidance scores are associated with anticipatory worry, fear of uncertainty, shyness and fatigability ŽPfohl et al., 1990; Svrakic et al., 1991.. The harm avoidance scale serves as a modulating influence on reward-seeking behavior ŽCloniger, 1986.. Persons scoring high on the reward dependence scale tend to be sentimental, socially sensitive, and dependent, and they readily form attachments to others ŽPfohl et al., 1990; Svrakic et al., 1991.. Personality features may predispose an individual to, result from, or modify the clinical presentation of psychiatric illnesses such as PGD and OCD. Also, comorbid personality disorders are often associated with poorer medication and therapy response as well as a poorer long-term prognosis ŽBattaglia et al., 1996.. Thus, a dimensional assessment of personality in patients with PGD and OCD may have both diagnostic and treatment implications. We hypothesized that PGD subjects would score significantly higher than OCD subjects and
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
normal controls with respect to novelty seeking given the impulsiveness pathological gamblers report clinically. Because of the almost pathological optimism reported by subjects with PGD concerning their chances to win at gambling activities, we hypothesized that pathological gamblers would score lower than OCD subjects and controls with respect to harm avoidance. And finally, given the repetitive behaviors associated both with pathological gambling and OCD, we hypothesized that reward dependence scores would be elevated in both PGD and OCD subjects compared with normal controls.
2. Materials and methods 2.1. Subjects The study subjects consisted of three groups drawn from two distinct pharmacological studies: subjects enrolled in a medication trial for pathological gambling disorder, subjects enrolled in a medication trial for obsessive᎐compulsive disorder, and normative controls. The first group consisted of 33 outpatients Ž19 males; 14 females; mean age s 48.3" 10.3 years. who met DSM-IV criteria for pathological gambling disorder and were enrolled in a double-blind paroxetineplacebo comparison study of PGD. Subjects were excluded from the medication trial if other current Axis I disorders were elicited by the Structured Clinical Interview for DSM-III-R ŽSCID. ŽSpitzer et al., 1992. or by diagnostic interview Žfor example, PGD., if they scored G 16 on either the 16-item Hamilton Depression Rating Scale ŽHDRS. ŽHamilton, 1960. or the Hamilton Anxiety Rating Scale ŽHARS. ŽHamilton, 1959., or if they reported significant medical problems or chemical dependency within the past 6 months. Subjects who had severe categorical DSM-IV Axis II personality disorders Žfor example, antisocial personality disorder, borderline personality disorder, obsessive᎐compulsive personality disorder. based on diagnostic evaluation were also excluded. Upon entry into the trial, and before medication was started, all subjects completed the TPQ.
207
Two hundred and twelve subjects were screened by telephone for the PGD medication trial from which the 33 current PGD subjects are drawn. Forty-six subjects consented to the study and underwent both a detailed diagnostic interview and the SCID, thirteen Ž28.3%. were excluded from the study Ž10 for major depressive disorder; 3 for alcohol abuse. based on the SCID. The second group consisted of 41 outpatients Ž30 males; 11 females; mean age s 41.8" 14.2 years . who met DSM-III-R criteria for obsessive᎐compulsive disorder and who participated in a multicenter paroxetine treatment study for OCD ŽWheadon et al., 1993.. Subjects were excluded from the OCD study if they had other current Axis I disorders by SCID ŽSpitzer et al., 1992. or had a DSM-III-R impulse control disorder Žfor example, PGD. elicited by clinical interview. Subjects were also excluded from the OCD study if they scored G 16 on either the 16-item HDRS ŽHamilton, 1960. or the HARS ŽHamilton, 1959., or exhibited a severe personality disorder based on clinical interview. Each OCD subject completed the TPQ prior to treatment. For the OCD study, 83 subjects were screened by telephone. Of those screened by telephone, 47 subjects signed consent forms, underwent a SCID, and were interviewed for Axis I disorders not on the SCID Žincluding PGD. and for Axis II disorders. Six subjects Ž12.8%. were excluded for having comorbid major depressive disorder. Controls included 29 males and 11 females Žmean age s 41.1" 13.7 years. derived from a sample of non-psychiatric, non-student adults who were employed in a university setting. Subjects were administered the SCID and underwent a detailed diagnostic interview screening for Axis I disorders not on the SCID Žfor example, PGD. and Axis II disorders. Subjects were excluded from participation if either a DSM-IV Axis I or Axis II disorder was elicited on the SCID or on clinical interview. All PGD and OCD subjects were recruited through newspaper advertisements for the two medication trials described above. Controls were recruited from university advertisements. Written informed consent was obtained from all study participants. The Institutional Review Board for
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
208
the University of Minnesota approved the two pharmacological studies and the consent forms. 2.2. Assessments Each subject completed the Tridimensional Personality Questionnaire ŽTPQ., a 100-item self-administered rating scale that assesses three personality dimensions Žeach with four subscales .: novelty seeking, reward dependence, and harm avoidance ŽCloninger, 1987.. The TPQ has been reported to be a valid and reliable measure based on normative data ŽCloninger et al., 1991.. The TPQ was chosen to assess personality because it characterizes personality dimensionally, not categorically, and further assesses behavioral components of those dimensions. Furthermore, there is evidence that the TPQ dimensions may relate to specific brain monoaminergic pathways Ždopamine, serotonin, and norepinephrine. ŽCloninger, 1986, 1987..
2.3. Statistical analysis PGD subjects were compared with OCD subjects and with normal controls with regard to each subscale score of the three personality dimensions. Between-group differences were tested using t-tests Žtwo-tailed. for continuous variables. Because there were significant multiple comparisons, we used a Bonferroni correction. Therefore, results that are statistically significant must be associated with a P-value - 0.0033. We do, however, include non-significant P-values in reporting the data but stress that an appropriate alpha level is 0.0033. Pearson correlation was used to assess the relationship of TPQ scores to baseline illness severity.
3. Results Subjects with PGD did not differ significantly
Table 1 Tridimensional Personality Questionnaire scores for pathological gamblers ŽPGD., patients with obsessive᎐compulsive disorder ŽOCD., and controls PGD patients Ž N s 33.
OCD patients Ž N s 41.
Controls Ž N s 40.
PGD vs. OCD Ž P-value.
PGD vs. controls Ž P-value.
No¨ elty seeking Exploratory excitability Impulsiveness Extravagance Disorderliness Total
4.97 Ž2.52. 4.67 Ž1.99. 5.52 Ž1.37. 4.94 Ž2.09. 20.10 Ž5.54.
4.05 Ž1.87. 2.29 Ž2.03. 3.71 Ž2.07. 3.71 Ž2.07. 13.76 Ž4.95.
4.13 Ž2.04. 3.00 Ž1.94. 3.40 Ž2.06. 3.98 Ž1.73. 14.51 Ž4.96.
0.076 0.000 0.000 0.014 0.000
0.128 0.001 0.000 0.035 0.000
Harm a¨ oidance Anticipatory worry Fear of uncertainty Shyness with strangers Fatigability Total
3.58 Ž2.08. 3.15 Ž1.97. 3.06 Ž2.22. 2.70 Ž2.79. 12.49 Ž6.90.
6.05 Ž2.63. 5.10 Ž2.08. 3.93 Ž2.13. 4.37 Ž2.79. 19.45 Ž6.97.
2.35 Ž2.27. 3.08 Ž2.26. 2.60 Ž2.26. 1.70 Ž2.31. 9.73 Ž6.94.
0.000 0.000 0.091 0.013 0.000
0.019 0.890 0.386 0.098 0.094
Reward dependence Sentimentality Persistence Attachment Dependence Total
3.85 Ž1.15. 5.61 Ž2.01. 5.88 Ž2.88. 2.76 Ž1.46. 18.10 Ž4.88.
3.54 Ž1.40. 5.66 Ž2.20. 5.29 Ž3.10. 2.88 Ž1.14. 17.37 Ž4.20.
3.68 Ž1.29. 5.78 Ž2.12. 5.48 Ž3.14. 2.93 Ž1.27. 17.87 Ž4.67.
0.309 0.920 0.404 0.692 0.492
0.558 0.728 0.576 0.596 0.838
Scores are averages Ž"S.D...
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
from those with OCD or the normal controls with respect to age Ž48.3 years compared to 41.8 years and 41.1 years, respectively.. All three groups had a larger percentage of males than females Ž57.6% in the PGD group; 73.2% in the OCD group; 72.5% in the control group., but the gender distribution did not differ significantly between the three groups. With respect to racial composition, all subjects were Caucasian. Table 1 summarizes between-group comparisons of TPQ scale scores. Patients with PGD had significantly higher scores on novelty seeking Ž t s 5.19; d.f.s 72., impulsiveness Ž t s 5.06; d.f.s 72., and extravagance Ž t s 4.32; d.f.s 72. compared to the subjects with OCD. The PGD subjects did, however, express significantly less anticipatory worry Ž t s y4.40; d.f.s 72., fear of uncertainty Ž t s y4.10; d.f.s 72., and harm avoidance Ž t s y4.29; d.f.s 72. than the OCD subjects. When compared to the normal control subjects, subjects with PGD again expressed significantly more impulsiveness Ž t s 3.62; d.f.s 71., extravagance Ž t s 5.06; d.f.s 71., and novelty seeking Ž t s 4.55; d.f.s 71.. In contrast to the comparison between PGD and OCD subjects, however, PGD subjects reported more anticipatory worry than the normal controls but this was not statistically significant Ž t s 2.39; d.f.s 71.. Reward dependence scores were similar between OCD and PGD subjects on all subscale measures. Furthermore, the reward dependence scores of PGD and OCD subjects were also similar to those for the normal controls. There was no correlation between severity of PGD or OCD symptoms and personality subscale scores. Subscale scores did not differ significantly between male and female OCD and PGD subjects.
4. Discussion
This study’s main findings are that PGD and OCD subjects have more differences than similarities in terms of personality dimensions. We found
209
that novelty seeking scores are significantly higher in PGD subjects compared to OCD patients and normal controls. Individuals who score high on the novelty seeking dimension are described as ‘curious, impulsive, quick-tempered, and disorderly’, while those with low scores ‘tend to be reflective, stoical, slow-tempered, and orderly’ ŽSvrakic et al., 1991.. High novelty seeking scores in PGD subjects are consistent with the literature, which that has found high levels of impulsivity among pathological gamblers ŽGraham and Lowenfeld, 1986; Ciarrocchi et al., 1991.. Unlike other studies that have associated impulsivity in gamblers with psychopathy ŽCunningham-Williams et al., 1998., however, our study excluded subjects who had antisocial personality disorder. Thus, in this sample, the impulsivity of pathological gamblers does not appear to be simply a consequence of a categorical personality disorder. High scores on the novelty seeking dimension have also been documented in manic patients ŽStrakowski et al., 1993.. The similarities in novelty seeking scores between PGD and mania are suggestive of a link between impulse control disorders and a bipolar spectrum of mental illness ŽMcElroy et al., 1996.. Case reports support the link to bipolar disorder by citing improvement in pathological gamblers using lithium and carbamazepine ŽMoskowitz, 1980; Haller and Hinterhuber, 1994.. Because of the association between the TPQ personality dimensions and neurotransmitter systems, there might also be an association between the high novelty seeking scores in pathological gamblers and dopamine activity. The role of dopamine in PGD is still unclear, but early evidence of pharmacological interventions suggests that dopamine dysregulation may contribute to the urges driving gambling behavior in pathological gamblers ŽKim and Grant, 2001.. Subjects with PGD also had significantly lower harm avoidance scores than the OCD subjects, and exhibited a trend Žalthough not statistically significant. toward elevated scores in comparison with the normal controls. High harm avoidance scores are associated with ‘apprehension, shyness, pessimism and fatigue’, whereas low scores are found in individuals who are ‘optimistic, carefree,
210
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
outgoing and energetic’ ŽSvrakic et al., 1991.. Elevated harm avoidance scores have been consistently seen in subjects with OCD ŽPfohl et al., 1990; Richter et al., 1996.. Although elevated avoidance scores Žreflecting a general neuroticism. may be a non-specific index of anxiety disorders ŽBrown et al., 1992., clinically avoidance accounts for the obsessional doubt and inability to tolerate ambiguity seen in OCD subjects. The fact that PGD subjects are significantly lower than OCD subjects in this dimension suggests that the obsessions of PGD may be more related to the urges to gamble than to the doubting seen in OCD subjects. The PGD subjects also showed a trend toward elevated harm avoidance scores compared to controls. The harm avoidance dimension is susceptible to mood states ŽJoffe et al., 1993., and the elevated scores may reflect subclinical depressive symptoms in the PGD subjects that did not meet DSM criteria for major depressive disorder. The slight elevation in harm avoidance scores is also consistent with the literature findings of elevated rates of avoidant personality disorder among pathological gamblers ŽBlack and Moyer, 1998.. Furthermore, harm avoidance may be associated with serotonergic dysfunction ŽCloninger, 1986.. The differences between OCD and PGD subjects with respect to harm avoidance may, therefore, suggest different pathophysiological mechanisms in these disorders. There were no differences seen in reward dependence scores between the three groups. Persons scoring high on this dimension tend to be ‘sentimental, socially sensitive, persistent and tender-hearted’ whereas those who score low tend to be ‘insensitive, practical, and tough-minded’ ŽSvrakic et al., 1991.. Given the tendency of OCD and PGD subjects to persist in repetitive behaviors, our finding of no differences in reward dependence scores between the groups is contrary to the prediction of elevated reward dependency scores in both OCD and PGD subjects. This finding is also inconsistent with the elevated reward dependence scores seen in OCD subjects compared to controls in a previous study ŽPfohl et al., 1990.. It is possible, however, that a clear
relationship between this dimension and either OCD or PGD is not robust enough to withstand the instabilities of small samples. One might, therefore, justifiably predict either low or high scores on this dimension in OCD or PGD subjects ŽPfohl et al., 1990.. This study suffers from several limitations. First, subjects were excluded from the study if they had comorbid Axis I disorders. Because comorbidity is a common feature of both clinical populations ŽMcElroy et al., 1994. and may affect personality findings, its exclusion may have artificially overor under-estimated the dimensional scores. Second, although the sample size had adequate power for the comparisons, the sample size is still relatively small. Because pathological gambling may often have both compulsive and impulsive features, a small sample may not adequately reflect the similarities or differences between PGD and OCD. Third, the process of selecting both PGD and OCD subjects with no other current comorbidity may also limit the generalizability of these findings to perhaps more representative samples of pathological gamblers. And finally, although no subject was diagnosed with a comorbid Axis I disorder, residual depressive symptoms not meeting full criteria for a major depressive episode may have affected the self-report measure. The present study has identified some differences in behavioral tendencies between subjects with PGD and those with OCD, and perhaps has added to the debate surrounding the proper classification of PGD. PGD has been diagnosed as a disorder of impulse control, a compulsive disorder, and an addiction. The notion of an obsessive᎐compulsive spectrum of disorders is based on similarities in associated clinical features Žage of onset, clinical course, comorbidity. and response to selective pharmacological treatment ŽSSRIs.. When PGD and OCD are analyzed from a dimensional personality perspective, however, the idea of an obsessive᎐compulsive spectrum may be overinclusive. These findings are, of course, preliminary. Further research using a dimensional approach to personality is needed to elucidate the similarities and differences between these disorders.
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
References
Battaglia, M., Przybeck, T.R., Bellodi, L., Cloninger, C.R., 1996. Temperament dimensions explain the comorbidity of psychiatric disorders. Comprehensive Psychiatry 37, 292᎐298. Bienvenu, O.J., Samuels, J.F., Riddle, M.A., Hoehn-Saric, R., Liang, K.Y., Cullen, B.A.M., Grados, M.A., Nestadt, G., 2000. The relationship of obsessive᎐compulsive disorder to possible spectrum disorders: results from a family study. Biological Psychiatry 48, 287᎐293. Black, D.W., Goldstein, R.B., Noyes, R., Blum, N., 1994. Compulsive behaviors and obsessive᎐compulsive disorder ŽOCD.: lack of a relationship between OCD, eating disorders, and gambling. Comprehensive Psychiatry 35, 145᎐148. Black, D.W., Moyer, T., 1998. Clinical features and psychiatric comorbidity of subjects with pathological gambling behavior. Psychiatric Services 49, 1434᎐1439. Blanco, C., Moreyra, P., Nunes, E.V., Saiz-Ruiz, J., Ibanez, A., 2001. Pathological gambling: addiction or compulsion? Seminars in Clinical Neuropsychiatry 6, 167᎐176. Bland, R.C., Newman, S.C., Orn, H., Stebelsky, G., 1993. Epidemiology of pathological gambling in Edmonton. Canadian Journal of Psychiatry 38, 108᎐112. Blaszczynski, A., 1999. Pathological gambling and obsessive᎐compulsive spectrum disorders. Psychological Reports 84, 107᎐113. Blaszczynski, A., Steel, Z.P., 1998. Personality disorders among pathological gamblers. Journal of Gambling Studies 14, 51᎐71. Brown, S.L., Svrakic, D.M., Przybeck, T.R., Cloninger, C.R., 1992. The relationship of personality to mood and anxiety states: a dimensional approach. Journal of Psychiatric Research 26, 197᎐211. Ciarrocchi, J.W., Kirschner, N., Fallik, F., 1991. Personality dimensions of male pathological gamblers, alcoholics, and dually addicted gamblers. Journal of Gambling Studies 7, 133᎐142. Cloninger, C.R., 1986. A unified biosocial theory of personality and its role in the development of anxiety states. Psychiatric Developments 4, 167᎐226. Cloninger, C.R., 1987. A systematic method for clinical description and classification of personality variants. Archives of General Psychiatry 44, 573᎐588. Cloninger, C.R., Przybeck, T.R., Svrakic, D.M., 1991. The Tridimensional Personality Questionnaire: US normative data. Psychological Reports 69, 1047᎐1057. Cunningham-Williams, R.M., Cottler, L.B., Compton, W.M., Spitznagel, E.L., 1998. Taking chances: problem gamblers and mental health disorders ᎏ results from the St. Louis Epidemiological Catchment Area ŽECA. Study. American Journal of Public Health 88, 1093᎐1096. Graham, J.R., Lowenfeld, B.H., 1986. Personality dimensions
211
of the pathological gambler. Journal of Gambling Behavior 2, 58᎐66. Haller, R., Hinterhuber, H., 1994. Treatment of pathological gambling with carbamazepine. Pharmacopsychiatry 27, 129. Hamilton, M., 1959. The assessment of anxiety states by rating. British Journal of Medical Psychiatry 32, 50᎐55. Hamilton, M., 1960. A rating scale for depression. Journal of Neurology, Neurosurgery and Psychiatry 23, 56᎐62. Hoehn-Saric, R., Barksdale, V.C., 1983. Impulsiveness in obsessive᎐compulsive patients. British Journal of Psychiatry 143, 177᎐182. Hollander, E., DeCaria, C.M., Finkell, J.N., Begaz, T., Wong, C.M., Cartwright, C., 2000. A randomized double-blind fluvoxaminerplacebo crossover trial in pathological gambling. Biological Psychiatry 47 Ž9., 813᎐817. Hollander, E., Stein, D.J., Kwon, J.H., 1997. Psychosocial function and economic costs of obsessive᎐compulsive disorder. CNS Spectrums 2, 16᎐25. Joffe, R.T., Bagby, R.M., Levitt, A.J., Regan, J.J., Parker, J.D.A., 1993. The Tridimensional Personality Questionnaire in major depression. American Journal of Psychiatry 150, 959᎐960. Kim, S.W., Grant, J.E., 2001. The psychopharmacology of pathological gambling. Seminars in Clinical Neuropsychiatry 6, 184᎐194. Linden, R.D., Pope Jr., H.G., Jonas, J.M., 1986. Pathological gambling and major affective disorder: preliminary findings. Journal of Clinical Psychiatry 47, 201᎐203. McElroy, S.L., Hudson, J.I., Phillips, K.A., Keck, P.E., Pope, H.G., 1993. Clinical and theoretical implications of a possible link between obsessive᎐compulsive and impulse control disorders. Depression 1, 121᎐132. McElroy, S.L., Phillips, K.A., Keck, P.E., 1994. Obsessive compulsive spectrum disorder. Journal of Clinical Psychiatry 55 Žsuppl 10., 33᎐51. McElroy, S.L., Pope Jr., H.G., Keck, P.E., Hudson, J.I., Phillips, K.A., Strakowski, S.M., 1996. Are impulse-control disorders related to bipolar disorder? Comprehensive Psychiatry 37, 229᎐240. Moskowitz, J.A., 1980. Lithium and lady luck: use of lithium carbonate in compulsive gambling. New York State Journal of Medicine 80, 785᎐788. Pfohl, B., Black, D., Noyes, R., Kelley, M., Blum, N., 1990. A test of the tridimensional personality theory: association with diagnosis and platelet imipramine binding in obsessive᎐compulsive disorder. Biological Psychiatry 28, 41᎐46. Richter, M.A., Summerfeldt, L.J., Joffe, R.T., Swinson, R.P., 1996. The Tridimensional Personality Questionnaire in obsessive᎐compulsive disorder. Psychiatry Research 65, 185᎐188. Spitzer, R.L., Williams, J.B., Gibbon, M., First, M.B., 1992. The Structured Clinical Interview for DSM-III-R. Archives of General Psychiatry 49, 624᎐629. Stein, D.J., Hollander, E., Simeon, D., Cohen, L., 1994. Impulsivity scores in patients with obsessive᎐compulsive disorder. Journal of Nervous and Mental Disease 182, 240᎐241.
212
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
Strakowski, S.M., Stoll, A.L., Tohen, M., Faedda, G.L., Goodwin, D.C., 1993. The Tridimensional Personality Questionnaire as a predictor of six-month outcome in first episode mania. Psychiatry Research 48, 1᎐8. Svrakic, D.M., Przybeck, T.R., Cloninger, C.R., 1991. Further contribution to the conceptual validity of the unified biosocial model of personality: U.S. and Yugoslav data. Comprehensive Psychiatry 32, 195᎐209.
Wheadon, D.E., Bushnell, W.D., Steiner, M., 1993. A fixed dose comparison of 20, 40, or 60 mg paroxetine to placebo in the treatment of obsessive᎐compulsive disorder. Presented at the 32nd Annual Meeting of the American College of Neuropsycho-pharmacology, Honolulu, Hawaii.
Personality dimensions in pathological gambling disorder and obsessive᎐compulsive disorder Suck Won KimU , Jon E. Grant Department of Psychiatry, Uni¨ ersity of Minnesota School of Medicine, F256 r 2A West, 2450 Ri¨ erside A¨ enue, Minneapolis, MN 55454-1495, USA Received 24 February 2001; received in revised form 15 August 2001; accepted 19 September 2001
Abstract This study was conducted to investigate the similarities and differences in the personality dimensions of patients with pathological gambling disorder ŽPGD. and obsessive᎐compulsive disorder ŽOCD.. Thirty-three subjects with PGD, 41 with OCD and 40 normal controls were assessed with the Tridimensional Personality Questionnaire ŽTPQ., which assesses three personality dimensions: novelty seeking, reward dependence, and harm avoidance. Compared with OCD subjects, PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. The PGD subjects also reported significantly less anticipatory worry, fear of uncertainty, and harm avoidance than the OCD subjects. Compared with controls, the PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. These results suggest that the personality dimensions of pathological gamblers may differ significantly from both those of OCD patients and normal controls. 䊚 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Tridimensional Personality Questionnaire; Impulsiveness; Obsessive᎐compulsive disorder
1. Introduction Pathological gambling, a disorder characterized by persistent and recurrent maladaptive patterns of gambling behavior, is classified as an impulse control disorder in DSM-IV, but has been noted to have similarities to obsessive᎐compulsive disorder ŽOCD. ŽMcElroy et al., 1993; Blanco et al., U
Corresponding author. Tel.: q1-612-273-9805; fax: q1612-273-9779. E-mail address: [email protected] ŽS. Won Kim..
2001.. Gambling activities, like OCD compulsions, are often experienced as uncontrollable and anxiety- or tension-relieving, may be resisted, are often followed by self-reproach, and are often denied ŽMcElroy et al., 1994.. Furthermore, treatment data suggest that pathological gambling disorder ŽPGD., like OCD, may respond to serotonin reuptake inhibitors ŽHollander et al., 2000; Kim and Grant, 2001.. There is, however, scant and contradictory literature concerning OCD or OCD traits in subjects with PGD. Two epidemiological studies are
0165-1781r01r$ - see front matter 䊚 2001 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 5 - 1 7 8 1 Ž 0 1 . 0 0 3 2 7 - 4
206
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
inconclusive concerning the rates of comorbid OCD in pathological gamblers. One study failed to find an increased odds ratio for OCD in subjects with PGD ŽCunningham-Williams et al., 1998., whereas the other study concluded that the relative risk for OCD in PGD was 7.2 ŽBland et al., 1993.. One study looking at rates of OCD in a small sample Ž N s 25. of pathological gamblers found that perhaps 20% suffered from comorbid OCD ŽLinden et al., 1986.. Reviewing the literature on OCD traits in pathological gamblers is also inconclusive. One study examining obsessions and compulsions Žusing the Padua Inventory. in subjects with PGD found that pathological gamblers scored significantly higher on obsessive᎐compulsiveness than normal controls, particularly on the element of ‘impaired control over mental activities’ ŽBlaszczynski, 1999.. These results, however, may highlight the obsessionality in pathological gamblers or may simply reflect adequate insight by subjects with PGD concerning their PGD symptoms ŽBlanco et al., 2001.. When assessing rates of comorbid PGD in subjects with OCD, however, the results do not support a strong association between the disorders. A study of 701 subjects with OCD found that less than 1% had a lifetime diagnosis of PGD ŽHollander et al., 1997.. A second study of 80 subjects with OCD found that no one had a current or lifetime diagnosis of PGD ŽBienvenu et al., 2000.. Even studies looking at first-degree relatives of subjects with OCD have found virtually no one who carries a diagnosis of PGD ŽBlack et al., 1994; Bienvenu et al., 2000. Obsessive᎐compulsive disorder and impulsivity may not be mutually exclusive, and impulsivity may instead index a subgroup of subjects with OCD ŽBlanco et al., 2001.. One study found that subjects with OCD and a history of impulsiveness scored higher on the Barratt Impulsiveness Scale than subjects with OCD and no history of impulsiveness ŽHoehn-Saric and Barksdale, 1983.. Supporting the view of OCD subjects as being harm avoidant, however, one study found that subjects with OCD did not score higher than normal controls on the Barratt Impulsiveness Scale ŽStein et al., 1994..
Little has been published on the prevalence of categorical personality disorders in subjects with PGD. A study of 30 subjects with PGD found high rates of obsessive᎐compulsive personality disorder Ž59%., avoidant personality disorder Ž50%., and schizoid and schizotypal personality disorders Ž33 and 30%, respectively. ŽBlack and Moyer, 1998.. One other study found that 93% of a group of subjects seeking gambling treatment met criteria for at least one personality disorder ŽBlaszczynski and Steel, 1998.. This study was conducted to investigate the similarities and differences in the personalities of patients with PGD and OCD. Unlike categorical assessments of personality disorders, the unified biosocial model of personality proposed by Cloninger identifies three heritable personality dimensions, each hypothesized to represent an independent behavioral response disposition ŽCloninger, 1986, 1987.. The Tridimensional Personality Questionnaire ŽTPQ. operationalizes these dimensions: novelty seeking; harm avoidance; and reward dependence. Individuals who score high on the novelty seeking dimension of the TPQ are thought to be impulsive, extravagant and disorderly ŽPfohl et al., 1990; Svrakic et al., 1991.. High avoidance scores are associated with anticipatory worry, fear of uncertainty, shyness and fatigability ŽPfohl et al., 1990; Svrakic et al., 1991.. The harm avoidance scale serves as a modulating influence on reward-seeking behavior ŽCloniger, 1986.. Persons scoring high on the reward dependence scale tend to be sentimental, socially sensitive, and dependent, and they readily form attachments to others ŽPfohl et al., 1990; Svrakic et al., 1991.. Personality features may predispose an individual to, result from, or modify the clinical presentation of psychiatric illnesses such as PGD and OCD. Also, comorbid personality disorders are often associated with poorer medication and therapy response as well as a poorer long-term prognosis ŽBattaglia et al., 1996.. Thus, a dimensional assessment of personality in patients with PGD and OCD may have both diagnostic and treatment implications. We hypothesized that PGD subjects would score significantly higher than OCD subjects and
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
normal controls with respect to novelty seeking given the impulsiveness pathological gamblers report clinically. Because of the almost pathological optimism reported by subjects with PGD concerning their chances to win at gambling activities, we hypothesized that pathological gamblers would score lower than OCD subjects and controls with respect to harm avoidance. And finally, given the repetitive behaviors associated both with pathological gambling and OCD, we hypothesized that reward dependence scores would be elevated in both PGD and OCD subjects compared with normal controls.
2. Materials and methods 2.1. Subjects The study subjects consisted of three groups drawn from two distinct pharmacological studies: subjects enrolled in a medication trial for pathological gambling disorder, subjects enrolled in a medication trial for obsessive᎐compulsive disorder, and normative controls. The first group consisted of 33 outpatients Ž19 males; 14 females; mean age s 48.3" 10.3 years. who met DSM-IV criteria for pathological gambling disorder and were enrolled in a double-blind paroxetineplacebo comparison study of PGD. Subjects were excluded from the medication trial if other current Axis I disorders were elicited by the Structured Clinical Interview for DSM-III-R ŽSCID. ŽSpitzer et al., 1992. or by diagnostic interview Žfor example, PGD., if they scored G 16 on either the 16-item Hamilton Depression Rating Scale ŽHDRS. ŽHamilton, 1960. or the Hamilton Anxiety Rating Scale ŽHARS. ŽHamilton, 1959., or if they reported significant medical problems or chemical dependency within the past 6 months. Subjects who had severe categorical DSM-IV Axis II personality disorders Žfor example, antisocial personality disorder, borderline personality disorder, obsessive᎐compulsive personality disorder. based on diagnostic evaluation were also excluded. Upon entry into the trial, and before medication was started, all subjects completed the TPQ.
207
Two hundred and twelve subjects were screened by telephone for the PGD medication trial from which the 33 current PGD subjects are drawn. Forty-six subjects consented to the study and underwent both a detailed diagnostic interview and the SCID, thirteen Ž28.3%. were excluded from the study Ž10 for major depressive disorder; 3 for alcohol abuse. based on the SCID. The second group consisted of 41 outpatients Ž30 males; 11 females; mean age s 41.8" 14.2 years . who met DSM-III-R criteria for obsessive᎐compulsive disorder and who participated in a multicenter paroxetine treatment study for OCD ŽWheadon et al., 1993.. Subjects were excluded from the OCD study if they had other current Axis I disorders by SCID ŽSpitzer et al., 1992. or had a DSM-III-R impulse control disorder Žfor example, PGD. elicited by clinical interview. Subjects were also excluded from the OCD study if they scored G 16 on either the 16-item HDRS ŽHamilton, 1960. or the HARS ŽHamilton, 1959., or exhibited a severe personality disorder based on clinical interview. Each OCD subject completed the TPQ prior to treatment. For the OCD study, 83 subjects were screened by telephone. Of those screened by telephone, 47 subjects signed consent forms, underwent a SCID, and were interviewed for Axis I disorders not on the SCID Žincluding PGD. and for Axis II disorders. Six subjects Ž12.8%. were excluded for having comorbid major depressive disorder. Controls included 29 males and 11 females Žmean age s 41.1" 13.7 years. derived from a sample of non-psychiatric, non-student adults who were employed in a university setting. Subjects were administered the SCID and underwent a detailed diagnostic interview screening for Axis I disorders not on the SCID Žfor example, PGD. and Axis II disorders. Subjects were excluded from participation if either a DSM-IV Axis I or Axis II disorder was elicited on the SCID or on clinical interview. All PGD and OCD subjects were recruited through newspaper advertisements for the two medication trials described above. Controls were recruited from university advertisements. Written informed consent was obtained from all study participants. The Institutional Review Board for
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
208
the University of Minnesota approved the two pharmacological studies and the consent forms. 2.2. Assessments Each subject completed the Tridimensional Personality Questionnaire ŽTPQ., a 100-item self-administered rating scale that assesses three personality dimensions Žeach with four subscales .: novelty seeking, reward dependence, and harm avoidance ŽCloninger, 1987.. The TPQ has been reported to be a valid and reliable measure based on normative data ŽCloninger et al., 1991.. The TPQ was chosen to assess personality because it characterizes personality dimensionally, not categorically, and further assesses behavioral components of those dimensions. Furthermore, there is evidence that the TPQ dimensions may relate to specific brain monoaminergic pathways Ždopamine, serotonin, and norepinephrine. ŽCloninger, 1986, 1987..
2.3. Statistical analysis PGD subjects were compared with OCD subjects and with normal controls with regard to each subscale score of the three personality dimensions. Between-group differences were tested using t-tests Žtwo-tailed. for continuous variables. Because there were significant multiple comparisons, we used a Bonferroni correction. Therefore, results that are statistically significant must be associated with a P-value - 0.0033. We do, however, include non-significant P-values in reporting the data but stress that an appropriate alpha level is 0.0033. Pearson correlation was used to assess the relationship of TPQ scores to baseline illness severity.
3. Results Subjects with PGD did not differ significantly
Table 1 Tridimensional Personality Questionnaire scores for pathological gamblers ŽPGD., patients with obsessive᎐compulsive disorder ŽOCD., and controls PGD patients Ž N s 33.
OCD patients Ž N s 41.
Controls Ž N s 40.
PGD vs. OCD Ž P-value.
PGD vs. controls Ž P-value.
No¨ elty seeking Exploratory excitability Impulsiveness Extravagance Disorderliness Total
4.97 Ž2.52. 4.67 Ž1.99. 5.52 Ž1.37. 4.94 Ž2.09. 20.10 Ž5.54.
4.05 Ž1.87. 2.29 Ž2.03. 3.71 Ž2.07. 3.71 Ž2.07. 13.76 Ž4.95.
4.13 Ž2.04. 3.00 Ž1.94. 3.40 Ž2.06. 3.98 Ž1.73. 14.51 Ž4.96.
0.076 0.000 0.000 0.014 0.000
0.128 0.001 0.000 0.035 0.000
Harm a¨ oidance Anticipatory worry Fear of uncertainty Shyness with strangers Fatigability Total
3.58 Ž2.08. 3.15 Ž1.97. 3.06 Ž2.22. 2.70 Ž2.79. 12.49 Ž6.90.
6.05 Ž2.63. 5.10 Ž2.08. 3.93 Ž2.13. 4.37 Ž2.79. 19.45 Ž6.97.
2.35 Ž2.27. 3.08 Ž2.26. 2.60 Ž2.26. 1.70 Ž2.31. 9.73 Ž6.94.
0.000 0.000 0.091 0.013 0.000
0.019 0.890 0.386 0.098 0.094
Reward dependence Sentimentality Persistence Attachment Dependence Total
3.85 Ž1.15. 5.61 Ž2.01. 5.88 Ž2.88. 2.76 Ž1.46. 18.10 Ž4.88.
3.54 Ž1.40. 5.66 Ž2.20. 5.29 Ž3.10. 2.88 Ž1.14. 17.37 Ž4.20.
3.68 Ž1.29. 5.78 Ž2.12. 5.48 Ž3.14. 2.93 Ž1.27. 17.87 Ž4.67.
0.309 0.920 0.404 0.692 0.492
0.558 0.728 0.576 0.596 0.838
Scores are averages Ž"S.D...
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
from those with OCD or the normal controls with respect to age Ž48.3 years compared to 41.8 years and 41.1 years, respectively.. All three groups had a larger percentage of males than females Ž57.6% in the PGD group; 73.2% in the OCD group; 72.5% in the control group., but the gender distribution did not differ significantly between the three groups. With respect to racial composition, all subjects were Caucasian. Table 1 summarizes between-group comparisons of TPQ scale scores. Patients with PGD had significantly higher scores on novelty seeking Ž t s 5.19; d.f.s 72., impulsiveness Ž t s 5.06; d.f.s 72., and extravagance Ž t s 4.32; d.f.s 72. compared to the subjects with OCD. The PGD subjects did, however, express significantly less anticipatory worry Ž t s y4.40; d.f.s 72., fear of uncertainty Ž t s y4.10; d.f.s 72., and harm avoidance Ž t s y4.29; d.f.s 72. than the OCD subjects. When compared to the normal control subjects, subjects with PGD again expressed significantly more impulsiveness Ž t s 3.62; d.f.s 71., extravagance Ž t s 5.06; d.f.s 71., and novelty seeking Ž t s 4.55; d.f.s 71.. In contrast to the comparison between PGD and OCD subjects, however, PGD subjects reported more anticipatory worry than the normal controls but this was not statistically significant Ž t s 2.39; d.f.s 71.. Reward dependence scores were similar between OCD and PGD subjects on all subscale measures. Furthermore, the reward dependence scores of PGD and OCD subjects were also similar to those for the normal controls. There was no correlation between severity of PGD or OCD symptoms and personality subscale scores. Subscale scores did not differ significantly between male and female OCD and PGD subjects.
4. Discussion
This study’s main findings are that PGD and OCD subjects have more differences than similarities in terms of personality dimensions. We found
209
that novelty seeking scores are significantly higher in PGD subjects compared to OCD patients and normal controls. Individuals who score high on the novelty seeking dimension are described as ‘curious, impulsive, quick-tempered, and disorderly’, while those with low scores ‘tend to be reflective, stoical, slow-tempered, and orderly’ ŽSvrakic et al., 1991.. High novelty seeking scores in PGD subjects are consistent with the literature, which that has found high levels of impulsivity among pathological gamblers ŽGraham and Lowenfeld, 1986; Ciarrocchi et al., 1991.. Unlike other studies that have associated impulsivity in gamblers with psychopathy ŽCunningham-Williams et al., 1998., however, our study excluded subjects who had antisocial personality disorder. Thus, in this sample, the impulsivity of pathological gamblers does not appear to be simply a consequence of a categorical personality disorder. High scores on the novelty seeking dimension have also been documented in manic patients ŽStrakowski et al., 1993.. The similarities in novelty seeking scores between PGD and mania are suggestive of a link between impulse control disorders and a bipolar spectrum of mental illness ŽMcElroy et al., 1996.. Case reports support the link to bipolar disorder by citing improvement in pathological gamblers using lithium and carbamazepine ŽMoskowitz, 1980; Haller and Hinterhuber, 1994.. Because of the association between the TPQ personality dimensions and neurotransmitter systems, there might also be an association between the high novelty seeking scores in pathological gamblers and dopamine activity. The role of dopamine in PGD is still unclear, but early evidence of pharmacological interventions suggests that dopamine dysregulation may contribute to the urges driving gambling behavior in pathological gamblers ŽKim and Grant, 2001.. Subjects with PGD also had significantly lower harm avoidance scores than the OCD subjects, and exhibited a trend Žalthough not statistically significant. toward elevated scores in comparison with the normal controls. High harm avoidance scores are associated with ‘apprehension, shyness, pessimism and fatigue’, whereas low scores are found in individuals who are ‘optimistic, carefree,
210
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
outgoing and energetic’ ŽSvrakic et al., 1991.. Elevated harm avoidance scores have been consistently seen in subjects with OCD ŽPfohl et al., 1990; Richter et al., 1996.. Although elevated avoidance scores Žreflecting a general neuroticism. may be a non-specific index of anxiety disorders ŽBrown et al., 1992., clinically avoidance accounts for the obsessional doubt and inability to tolerate ambiguity seen in OCD subjects. The fact that PGD subjects are significantly lower than OCD subjects in this dimension suggests that the obsessions of PGD may be more related to the urges to gamble than to the doubting seen in OCD subjects. The PGD subjects also showed a trend toward elevated harm avoidance scores compared to controls. The harm avoidance dimension is susceptible to mood states ŽJoffe et al., 1993., and the elevated scores may reflect subclinical depressive symptoms in the PGD subjects that did not meet DSM criteria for major depressive disorder. The slight elevation in harm avoidance scores is also consistent with the literature findings of elevated rates of avoidant personality disorder among pathological gamblers ŽBlack and Moyer, 1998.. Furthermore, harm avoidance may be associated with serotonergic dysfunction ŽCloninger, 1986.. The differences between OCD and PGD subjects with respect to harm avoidance may, therefore, suggest different pathophysiological mechanisms in these disorders. There were no differences seen in reward dependence scores between the three groups. Persons scoring high on this dimension tend to be ‘sentimental, socially sensitive, persistent and tender-hearted’ whereas those who score low tend to be ‘insensitive, practical, and tough-minded’ ŽSvrakic et al., 1991.. Given the tendency of OCD and PGD subjects to persist in repetitive behaviors, our finding of no differences in reward dependence scores between the groups is contrary to the prediction of elevated reward dependency scores in both OCD and PGD subjects. This finding is also inconsistent with the elevated reward dependence scores seen in OCD subjects compared to controls in a previous study ŽPfohl et al., 1990.. It is possible, however, that a clear
relationship between this dimension and either OCD or PGD is not robust enough to withstand the instabilities of small samples. One might, therefore, justifiably predict either low or high scores on this dimension in OCD or PGD subjects ŽPfohl et al., 1990.. This study suffers from several limitations. First, subjects were excluded from the study if they had comorbid Axis I disorders. Because comorbidity is a common feature of both clinical populations ŽMcElroy et al., 1994. and may affect personality findings, its exclusion may have artificially overor under-estimated the dimensional scores. Second, although the sample size had adequate power for the comparisons, the sample size is still relatively small. Because pathological gambling may often have both compulsive and impulsive features, a small sample may not adequately reflect the similarities or differences between PGD and OCD. Third, the process of selecting both PGD and OCD subjects with no other current comorbidity may also limit the generalizability of these findings to perhaps more representative samples of pathological gamblers. And finally, although no subject was diagnosed with a comorbid Axis I disorder, residual depressive symptoms not meeting full criteria for a major depressive episode may have affected the self-report measure. The present study has identified some differences in behavioral tendencies between subjects with PGD and those with OCD, and perhaps has added to the debate surrounding the proper classification of PGD. PGD has been diagnosed as a disorder of impulse control, a compulsive disorder, and an addiction. The notion of an obsessive᎐compulsive spectrum of disorders is based on similarities in associated clinical features Žage of onset, clinical course, comorbidity. and response to selective pharmacological treatment ŽSSRIs.. When PGD and OCD are analyzed from a dimensional personality perspective, however, the idea of an obsessive᎐compulsive spectrum may be overinclusive. These findings are, of course, preliminary. Further research using a dimensional approach to personality is needed to elucidate the similarities and differences between these disorders.
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
References
Battaglia, M., Przybeck, T.R., Bellodi, L., Cloninger, C.R., 1996. Temperament dimensions explain the comorbidity of psychiatric disorders. Comprehensive Psychiatry 37, 292᎐298. Bienvenu, O.J., Samuels, J.F., Riddle, M.A., Hoehn-Saric, R., Liang, K.Y., Cullen, B.A.M., Grados, M.A., Nestadt, G., 2000. The relationship of obsessive᎐compulsive disorder to possible spectrum disorders: results from a family study. Biological Psychiatry 48, 287᎐293. Black, D.W., Goldstein, R.B., Noyes, R., Blum, N., 1994. Compulsive behaviors and obsessive᎐compulsive disorder ŽOCD.: lack of a relationship between OCD, eating disorders, and gambling. Comprehensive Psychiatry 35, 145᎐148. Black, D.W., Moyer, T., 1998. Clinical features and psychiatric comorbidity of subjects with pathological gambling behavior. Psychiatric Services 49, 1434᎐1439. Blanco, C., Moreyra, P., Nunes, E.V., Saiz-Ruiz, J., Ibanez, A., 2001. Pathological gambling: addiction or compulsion? Seminars in Clinical Neuropsychiatry 6, 167᎐176. Bland, R.C., Newman, S.C., Orn, H., Stebelsky, G., 1993. Epidemiology of pathological gambling in Edmonton. Canadian Journal of Psychiatry 38, 108᎐112. Blaszczynski, A., 1999. Pathological gambling and obsessive᎐compulsive spectrum disorders. Psychological Reports 84, 107᎐113. Blaszczynski, A., Steel, Z.P., 1998. Personality disorders among pathological gamblers. Journal of Gambling Studies 14, 51᎐71. Brown, S.L., Svrakic, D.M., Przybeck, T.R., Cloninger, C.R., 1992. The relationship of personality to mood and anxiety states: a dimensional approach. Journal of Psychiatric Research 26, 197᎐211. Ciarrocchi, J.W., Kirschner, N., Fallik, F., 1991. Personality dimensions of male pathological gamblers, alcoholics, and dually addicted gamblers. Journal of Gambling Studies 7, 133᎐142. Cloninger, C.R., 1986. A unified biosocial theory of personality and its role in the development of anxiety states. Psychiatric Developments 4, 167᎐226. Cloninger, C.R., 1987. A systematic method for clinical description and classification of personality variants. Archives of General Psychiatry 44, 573᎐588. Cloninger, C.R., Przybeck, T.R., Svrakic, D.M., 1991. The Tridimensional Personality Questionnaire: US normative data. Psychological Reports 69, 1047᎐1057. Cunningham-Williams, R.M., Cottler, L.B., Compton, W.M., Spitznagel, E.L., 1998. Taking chances: problem gamblers and mental health disorders ᎏ results from the St. Louis Epidemiological Catchment Area ŽECA. Study. American Journal of Public Health 88, 1093᎐1096. Graham, J.R., Lowenfeld, B.H., 1986. Personality dimensions
211
of the pathological gambler. Journal of Gambling Behavior 2, 58᎐66. Haller, R., Hinterhuber, H., 1994. Treatment of pathological gambling with carbamazepine. Pharmacopsychiatry 27, 129. Hamilton, M., 1959. The assessment of anxiety states by rating. British Journal of Medical Psychiatry 32, 50᎐55. Hamilton, M., 1960. A rating scale for depression. Journal of Neurology, Neurosurgery and Psychiatry 23, 56᎐62. Hoehn-Saric, R., Barksdale, V.C., 1983. Impulsiveness in obsessive᎐compulsive patients. British Journal of Psychiatry 143, 177᎐182. Hollander, E., DeCaria, C.M., Finkell, J.N., Begaz, T., Wong, C.M., Cartwright, C., 2000. A randomized double-blind fluvoxaminerplacebo crossover trial in pathological gambling. Biological Psychiatry 47 Ž9., 813᎐817. Hollander, E., Stein, D.J., Kwon, J.H., 1997. Psychosocial function and economic costs of obsessive᎐compulsive disorder. CNS Spectrums 2, 16᎐25. Joffe, R.T., Bagby, R.M., Levitt, A.J., Regan, J.J., Parker, J.D.A., 1993. The Tridimensional Personality Questionnaire in major depression. American Journal of Psychiatry 150, 959᎐960. Kim, S.W., Grant, J.E., 2001. The psychopharmacology of pathological gambling. Seminars in Clinical Neuropsychiatry 6, 184᎐194. Linden, R.D., Pope Jr., H.G., Jonas, J.M., 1986. Pathological gambling and major affective disorder: preliminary findings. Journal of Clinical Psychiatry 47, 201᎐203. McElroy, S.L., Hudson, J.I., Phillips, K.A., Keck, P.E., Pope, H.G., 1993. Clinical and theoretical implications of a possible link between obsessive᎐compulsive and impulse control disorders. Depression 1, 121᎐132. McElroy, S.L., Phillips, K.A., Keck, P.E., 1994. Obsessive compulsive spectrum disorder. Journal of Clinical Psychiatry 55 Žsuppl 10., 33᎐51. McElroy, S.L., Pope Jr., H.G., Keck, P.E., Hudson, J.I., Phillips, K.A., Strakowski, S.M., 1996. Are impulse-control disorders related to bipolar disorder? Comprehensive Psychiatry 37, 229᎐240. Moskowitz, J.A., 1980. Lithium and lady luck: use of lithium carbonate in compulsive gambling. New York State Journal of Medicine 80, 785᎐788. Pfohl, B., Black, D., Noyes, R., Kelley, M., Blum, N., 1990. A test of the tridimensional personality theory: association with diagnosis and platelet imipramine binding in obsessive᎐compulsive disorder. Biological Psychiatry 28, 41᎐46. Richter, M.A., Summerfeldt, L.J., Joffe, R.T., Swinson, R.P., 1996. The Tridimensional Personality Questionnaire in obsessive᎐compulsive disorder. Psychiatry Research 65, 185᎐188. Spitzer, R.L., Williams, J.B., Gibbon, M., First, M.B., 1992. The Structured Clinical Interview for DSM-III-R. Archives of General Psychiatry 49, 624᎐629. Stein, D.J., Hollander, E., Simeon, D., Cohen, L., 1994. Impulsivity scores in patients with obsessive᎐compulsive disorder. Journal of Nervous and Mental Disease 182, 240᎐241.
212
S. Won Kim, J.E. Grant r Psychiatry Research 104 (2001) 205᎐212
Strakowski, S.M., Stoll, A.L., Tohen, M., Faedda, G.L., Goodwin, D.C., 1993. The Tridimensional Personality Questionnaire as a predictor of six-month outcome in first episode mania. Psychiatry Research 48, 1᎐8. Svrakic, D.M., Przybeck, T.R., Cloninger, C.R., 1991. Further contribution to the conceptual validity of the unified biosocial model of personality: U.S. and Yugoslav data. Comprehensive Psychiatry 32, 195᎐209.
Wheadon, D.E., Bushnell, W.D., Steiner, M., 1993. A fixed dose comparison of 20, 40, or 60 mg paroxetine to placebo in the treatment of obsessive᎐compulsive disorder. Presented at the 32nd Annual Meeting of the American College of Neuropsycho-pharmacology, Honolulu, Hawaii.