Official journal of the Pacific Rim College of Psychiatrists
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Asia-Pacific Psychiatry ISSN 1758-5864
ORIGINAL ARTICLE
Minnesota Multiphasic Personality Inventory profile in patients with restless legs syndrome Yakup Turkel1 MD, Omer Oguzturk2 PhD, Ersel Dag1 MD, S. Visal Buturak2 MD & Mehmet S. Ekici3 MD 1 Department of Neurology, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey 2 Department of Psychiatry, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey 3 Department of Pulmonary Diseases, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey
Keywords MMPI, personality trait, psychiatric disorder, restless legs syndrome Correspondence Yakup Turkel Department of Neurology, Faculty of Medicine, Kirikkale University, 71100 Kirikkale, Turkey. Tel: +90 318 444 4071/5008 Fax: +90 318 224 0786 Email: [email protected] Conflict of interest: There are no conflicts of interest. Received 12 March 2014 Accepted 5 August 2014
Abstract Introduction: Restless legs syndrome (RLS) is associated with psychiatric disorders. We aim to investigate the personality traits of RLS patients using the Minnesota Multiphasic Personality Inventory. Methods: Twenty adult patients with RLS (14 females and 6 males) and 20 healthy controls (14 females and 6 males) who were referred to university neurology were enrolled in the present study. Diagnosis of RLS was established using International Restless Legs Syndrome Study Group. Psychometric evaluation was made with the Turkish version of the Minnesota Multiphasic Personality Inventory. Results: RLS patients have significantly higher absolute and clinical elevation scores on hypochondriasis and hysteria, and clinical elevation scores on psychasthenia, compared with the controls. Absolute scores on depression were higher at the border in RLS patients compared with the controls. Discussion: RLS patients have hypochondriac, hysterical, depressive, and anxious personality traits.
DOI:10.1111/appy.12151
Introduction Restless legs syndrome (RLS) is a neurological disorder characterized by unpleasant sensations in the legs and a distressing, irresistible urge to move them. RLS affects about 5–10% of the general population (Phillips et al., 2000; Hening et al., 2004; Picchietti and Winkelman, 2005). The prevalence of RLS was reported to be 3.19% in a study conducted in Turkey (Sevim et al., 2003). Many studies have observed a higher prevalence for RLS in women than in men (Ohayon and Roth, 2002; Högl et al., 2005). There is a primary or secondary form of RLS. Secondary forms are often related with anemia, end-stage renal failure, diabetes mellitus, hypothyroidism, Parkinson’s disease, and pregnancy (Chokrovertry and Jankovic, 1999; Chaudhuri et al., 2004). Although pathophysiology is not fully understood, it is thought to arise from iron and dopamine metabolism irregularities, and has a genetic
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
component (Walters et al., 2003). RLS is a common cause of insomnia related to problems with sleep initiation and sleep maintenance, unrefreshing sleep, and excessive daytime sleepiness, and it may signify an underlying medical condition. Recognition of the condition and appropriate treatment, therefore, have a large impact on morbidity and quality of life (Leschziner and Gringras, 2012). RLS is also associated with a broad variety of other psychiatric disorders, such as depressive symptoms, dysthymia, general anxiety disorders, and panic disorder (Brand et al., 2013). In the present study, we aim to investigate the effects on personality of RLS using the Minnesota Multiphasic Personality Inventory (MMPI). Because the standardization of the scale of MMPI in the Turkish population has been reported (Savas¸ır, 1981; Erol, 1982), and MMPI has Turkish norms for normal, medical, and psychiatric patients, MMPI was chosen to assess the personality traits of the subjects.
153
MMPI and restless legs syndrome
Methods The study was approved by the local ethics committee. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent/permission was obtained from all parent participants and child assent from patient participants for being included in the study. Twenty adult patients with RLS (14 females and 6 males) and 20 healthy controls (14 females and 6 males) who were referred to university neurology clinic were enrolled in the present study. Demographic characteristics, including age, gender, education levels, medical history, and drug intake, were recorded. A detailed neurological examination was performed, as well as laboratory tests, including urea, creatinine, liver function, electrolytes, vitamin B12, complete blood count, iron, iron binding capacity, ferritin, and thyroid function. Exclusion criteria included known neurodegenerative and psychiatric disorders, secondary RLS (expected anemia), and uneducated individuals. The study was approved by the local ethics committee. Diagnosis of RLS was established in subjects with suspected RLS using International Restless Legs Syndrome Study Group diagnostic criteria, including (i) urge to move the legs, usually accompanied or caused by uncomfortable leg sensations; (ii) temporary relief with movement, partial or total relief from discomfort by walking or stretching; (iii) onset or worsening of symptoms at rest or inactivity, such as when lying down or sitting; and (iv) worsening or onset of symptoms in the evening or at night (Walters et al., 2003). Psychometric evaluation Each patient underwent psychometric evaluation with the Turkish version of the MMPI (Savas¸ır, 1981; Erol, 1982), which consists of 566 statements answered as “true” or “false,” as applies to the patient. The scoring results in a standard profile that consists of three “validity scales” and ten “personality scales.” The validity scales consist of lie, fake, and defensive responses, and validate each profile. Subjects scoring beyond predetermined limits on these scales have answered the test with bias, invalidating the results of the personality scales. In this study, there are no biased profiles. The personality scales score characteristics that are based on psychodiagnostic categories. They are not considered to be indicators of
154
Y. Turkel et al.
psychopathology per se, but personal characteristics that are somewhat related to the content description of the category. The personality scales consist of hypochondriasis, depression, hysteria, psychopathic deviate, masculinity–femininity, paranoia, psychasthenia, schizophrenia, hypomania, and social introversion. Results of the MMPI test are expressed in standardized t-scores. Thus, a scale score is considered indicative of psychological dysfunction when t-value is >65. We dichotomously classified each individual subject in terms of whether or not each scale fell in the clinically elevated range. Elevation was defined as t-score >65. Absolute scores were mean of standardized t-scores.
Statistical methods All clinical parameters were expressed as mean ± SD, as well as percentages (for categorical variables). Patients with RLS and healthy controls were compared using one-way analysis of variance for continuous parameters, and chi-squared test for categorical parameters. A P-value of 0.05). There was no difference between both groups in terms of gender and education levels (P > 0.05). Table 1 shows the means (SD) and percentage of sample elevated (t > 65) for MMPI clinical scales in patient and control groups. RLS patients have significantly higher absolute scores on hypochondriasis compared with the controls (65.2 ± 10.8 versus 49.6 ± 10.1, P = 0.001). RLS patients have also significantly higher absolute scores on hysteria compared with the controls (64.5 ± 9.2 versus 43.6 ± 7.4, P = 0.001). Absolute scores on depression were higher at the border in RLS patients compared with the controls (55.7 ± 9.7 versus 50.3 ± 7.8, P = 0.05). RLS patients have higher rates of clinical elevation on hypochondriasis, hysteria, and psychasthenia (50.0, P = 0.004; 35.0, P = 0.001; 20.0, P = 0.01, respectively).
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
Y. Turkel et al.
MMPI and restless legs syndrome
Table 1. Means (SD) and percentage of sample elevated (t > 65) for MMPI clinical scales in patients and controls Patients (n = 20)
Controls (n = 20)
MMPI clinical scale
Mean ± SD
% Elevated
Mean ± SD
% Elevated
P-values†
Hypochondriasis Depression Hysteria Psychopathic deviate Masculinity/femininity Paranoia Psychasthenia Schizophrenia Hypomania Social introversion MMPI mean t-score Number of elevations
65.2 ± 10.8 55.7 ± 9.7 64.5 ± 9.2 52.3 ± 10.8 56.4 ± 10.5 52.4 ± 10.4 53.9 ± 8.8 50.9 ± 9.6 51.4 ± 9.7 53.8 ± 12.9 55.6 ± 6.5 1.9 ± 1.6
50.0 20.0 35.0 10.0 20.0 10.0 20.0 10.0 5.0 10.0
49.6 ± 10.1* 50.3 ± 7.8** 43.6 ± 7.4*** 48.9 ± 10.5 59.5 ± 9.0 51.2 ± 10.6 48.1 ± 9.5 47.6 ± 10.3 53.1 ± 7.7 51.9 ± 7.3 50.4 ± 5.4**** 0.8 ± 0.8
10.0 5.0 0 15.0 25.0 5.0 0 5.0 10.0 5.0
0.004 0.13 0.001 0.63 0.7 0.54 0.01 0.54 0.54 0.54
*P = 0.001; **P = 0.05; ***P = 0.001; ****P = 0.009. †Comparison of percentage of sample elevated (t > 65) for MMPI clinical scales. MMPI, Minnesota Multiphasic Personality Inventory. Significant p-values are shown in the italics format.
Discussion This is the first study to examine personality traits in persons with RLS using the MMPI. We found that individuals with RLS had higher hysteria scores than non-RLS controls. Neuroticism is a personality trait characterized by anxiety, moodiness, worry, envy, and grudge. Neuroticism is the tendency to experience negative emotions, such as anger, anxiety, or depression. Neuroticism is sometimes called emotional instability (Thompson, 2008). Histrionic personality disorder (HPD) is defined by the American Psychiatric Association as a personality disorder characterized by a pattern of excessive emotions and attention-seeking, including inappropriately seductive behavior and an excessive need for approval, usually beginning in early adulthood. People affected by HPD are lively, dramatic, vivacious, and enthusiastic (DSM-IV-TR Diagnostic and Statistical Manual of Mental Disorders, 2000). HPD overlaps with neuroticism characterized with emotional instability. Kalaydjian et al. (2009) found that individuals with RLS have higher mean neuroticism factor scores than non-RLS controls. In this study, personality traits were assessed using the revised NEO Personality Inventory. The authors suggested that high neuroticism may be a predisposing factor for RLS, and therefore may mediate the association of RLS with mood and anxiety disorders. Besides, the authors suggested that the sleep deprivation inherent in RLS and impaired quality of life may enhance neuroticism in RLS patients. They also claimed that neuroticism and
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
RLS may result from a similar etiology. This relationship was found to be related with dopamine (Kalaydjian et al., 2009). We believe that similar mechanisms may affect the patients. Another explanation may be as follows. Histrionic personality traits are a situation that there is exaggerated attract attention behavior. Hysteria rate elevation determined in the MMPI may be a reflection of personality traits that complaints were exaggerated in RLS patients admitted to our clinic. The present study indicated that RLS patients had a significantly higher rate of hypochondriasis scores than non-RLS controls. General hypochondriacal complaints were seen with manifestations of a somatization or psychophysiological reaction. Even when or if they had real physical symptoms, patients were found to exaggerate their severity (Bayar et al., 2001). It is possible that the psychopathology might reflect the effects of symptoms secondary to disease more than the direct effects of sleep disturbance per se (Ekici et al., 2013). The present study showed that RLS patients had higher depression absolute scores than non-RLS controls. Previous studies have shown that the risk of depression increases in RLS patients (Rothdach et al., 2000; Sevim et al., 2004). Possible mechanisms of specific depressive symptoms in RLS have not been exactly known. It could be that sleep disturbances may increase the risk of these disorders, and it is well known that sleep disturbances can increase the risk of depressive disorders (Rothdach et al., 2000). High depression scores in RLS may also be related to neuroticism. The present study indicated that RLS patients had a significantly higher rate of psychasthenia clinical
155
MMPI and restless legs syndrome
elevation scores than non-RLS controls. Elevation in psychasthenia clinical elevation scores refers to anxiety disorders (Erol, 1982; Thompson, 2008). Clinical association of RLS and anxiety disorders has also been described (Winkelmann et al., 2005). Gorman et al. (1965) found higher scores on depression and psychasthenia scales in RLS patients than both the general population and psychiatric referrals. The authors suggested that impairment of sleep and chronic sleep deprivation caused by RLS is likely to be the chief cause of anxiety. The present study indicates that hypochondriac, hysteric, depressive, and psychasthenia personality characteristics were exhibited by RLS patients. Clinicians evaluating RLS patients should be aware that the disease may be accompanied by psychological disturbance. References Frances A., Pıncus H.A., First M.B., et al. (2000) Personality disorders. In: First M.B., ed. DSM-IV-TR Diagnostic and Statistical Manual of Mental Disorders. American Psychiatric Publishing, American Psychiatric Association, chapter 16. Bayar N., Oguztürk O., Kazkayasi M., Koç M.C. (2001) Minnesota Multiphasic Personality Inventory profile of patients with chronic sinusitis. Rhinology. 39, 133–135. Brand S., Beck J., Hatzinger M., Holsboer-Trachsler E. (2013) Patients suffering from restless legs syndrome have low internal locus of control and poor psychological functioning compared to healthy controls. Neuropsychobiology. 68(1), 51–58. Chaudhuri K.R., Forbes A., Grosset D., et al. (2004) Diagnosing restless legs syndrome (RLS) in primary care. Curr Med Res Opin. 20, 1785–1795. Chokrovertry S., Jankovic J. (1999) Restless legs syndrome: a disease in search of identity. Neurology. 52, 907–910. Ekici A., Ekici M., Og˘uztürk O., Karabog˘a I., Cimen D., Senturk E. (2013) Personality profiles in patients with obstructive sleep apnea. Sleep Breath. 17, 305–310.
Y. Turkel et al.
and treatment of restless legs syndrome (RLS) in a primary care population: the REST (RLS epidemiology, symptoms and treatment) primary care study. Sleep Med. 5, 237–246. Högl B., Kiechl S., Willeit J., et al. (2005) Restless legs syndrome: a community-based study of prevalence, severity, and risk factors. Neurology. 64, 1920–1924. Kalaydjian A., Bienvenu O.J., Hening W.A., Allen R.P., Eaton W.W., Lee H.B. (2009) Restless legs syndrome and the five-factor model of personality: results from a community sample. Sleep Med. 10, 672–675. Leschziner G., Gringras P. (2012) Restless legs syndrome. BMJ. 344, e3056. Ohayon M.M., Roth T. (2002) Prevalence of restless legs syndrome and periodic limb movement disorder in the general population. J Psychosom Res. 53, 547–554. Phillips B., Young T., Finn L., Asher K., Hening W.A., Purvis C. (2000) Epidemiology of restless legs symptoms in adults. Arch Intern Med. 160, 2137–2141. Picchietti D., Winkelman J.W. (2005) Restless legs syndrome, periodic limb movements in sleep, and depression. Sleep. 28, 891–898. Rothdach A.J., Trenkwalder C., Haberstock J., Keil U., Berger K. (2000) Prevalence and risk factors of RLS in an elderly population. Neurology. 54, 1064–1068. Savas¸ır I. (1981) Minesota Çok Yönlü Kis¸ilik Envanteri-Elkitabı (TürkStandardizasyonu). Sevinç Matbaası, Ankara. Sevim S., Dogu O., Camdeviren H., et al. (2003) Unexpectedly low prevalence and unusual characteristics of RLS in Mersin, Turkey. Neurology. 6, 1562–1569. Sevim S., Dogu O., Kaleagasi H., Aral M., Metin O., Camdeviren H. (2004) Correlation of anxiety and depression symptoms in patients with restless legs syndrome: a population based survey. J Neurol Neurosurg Psychiatry. 75, 226–230. Thompson E.R. (2008) Development and validation of an international English big-five mini-markers. Pers Individ Dif. 45, 542–548.
Erol N. (1982) Ülkemizde Psikiyatrik Hastalarda Minnesota Çok Yönlü Kis¸ilik Envanterinin Geçerlik Aras¸tırması. DTCF Psikoloji Kürsüsü, Doktora Tezi. AÜ.
Walters A.S., LeBrocq C., Dhar A., et al. (2003) Validation of the International Restless Legs Syndrome Study Group rating scale for restless legs syndrome. Sleep Med. 4, 121–132.
Gorman C.A., Dyck P.J., Pearson J.S. (1965) Symptoms of restless legs. Arch Intern Med. 115, 155–160.
Winkelmann J., Prager M., Lieb R., et al. (2005) “Anxietas tibiarum”. Depression and anxiety disorders in patients with restless legs syndrome. J Neurol. 252, 67–71.
Hening W., Walters A.S., Allen R.P., Montplaisir J., Myers A., Ferini-Strambi L. (2004) Impact, diagnosis
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Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
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Asia-Pacific Psychiatry ISSN 1758-5864
ORIGINAL ARTICLE
Minnesota Multiphasic Personality Inventory profile in patients with restless legs syndrome Yakup Turkel1 MD, Omer Oguzturk2 PhD, Ersel Dag1 MD, S. Visal Buturak2 MD & Mehmet S. Ekici3 MD 1 Department of Neurology, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey 2 Department of Psychiatry, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey 3 Department of Pulmonary Diseases, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey
Keywords MMPI, personality trait, psychiatric disorder, restless legs syndrome Correspondence Yakup Turkel Department of Neurology, Faculty of Medicine, Kirikkale University, 71100 Kirikkale, Turkey. Tel: +90 318 444 4071/5008 Fax: +90 318 224 0786 Email: [email protected] Conflict of interest: There are no conflicts of interest. Received 12 March 2014 Accepted 5 August 2014
Abstract Introduction: Restless legs syndrome (RLS) is associated with psychiatric disorders. We aim to investigate the personality traits of RLS patients using the Minnesota Multiphasic Personality Inventory. Methods: Twenty adult patients with RLS (14 females and 6 males) and 20 healthy controls (14 females and 6 males) who were referred to university neurology were enrolled in the present study. Diagnosis of RLS was established using International Restless Legs Syndrome Study Group. Psychometric evaluation was made with the Turkish version of the Minnesota Multiphasic Personality Inventory. Results: RLS patients have significantly higher absolute and clinical elevation scores on hypochondriasis and hysteria, and clinical elevation scores on psychasthenia, compared with the controls. Absolute scores on depression were higher at the border in RLS patients compared with the controls. Discussion: RLS patients have hypochondriac, hysterical, depressive, and anxious personality traits.
DOI:10.1111/appy.12151
Introduction Restless legs syndrome (RLS) is a neurological disorder characterized by unpleasant sensations in the legs and a distressing, irresistible urge to move them. RLS affects about 5–10% of the general population (Phillips et al., 2000; Hening et al., 2004; Picchietti and Winkelman, 2005). The prevalence of RLS was reported to be 3.19% in a study conducted in Turkey (Sevim et al., 2003). Many studies have observed a higher prevalence for RLS in women than in men (Ohayon and Roth, 2002; Högl et al., 2005). There is a primary or secondary form of RLS. Secondary forms are often related with anemia, end-stage renal failure, diabetes mellitus, hypothyroidism, Parkinson’s disease, and pregnancy (Chokrovertry and Jankovic, 1999; Chaudhuri et al., 2004). Although pathophysiology is not fully understood, it is thought to arise from iron and dopamine metabolism irregularities, and has a genetic
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
component (Walters et al., 2003). RLS is a common cause of insomnia related to problems with sleep initiation and sleep maintenance, unrefreshing sleep, and excessive daytime sleepiness, and it may signify an underlying medical condition. Recognition of the condition and appropriate treatment, therefore, have a large impact on morbidity and quality of life (Leschziner and Gringras, 2012). RLS is also associated with a broad variety of other psychiatric disorders, such as depressive symptoms, dysthymia, general anxiety disorders, and panic disorder (Brand et al., 2013). In the present study, we aim to investigate the effects on personality of RLS using the Minnesota Multiphasic Personality Inventory (MMPI). Because the standardization of the scale of MMPI in the Turkish population has been reported (Savas¸ır, 1981; Erol, 1982), and MMPI has Turkish norms for normal, medical, and psychiatric patients, MMPI was chosen to assess the personality traits of the subjects.
153
MMPI and restless legs syndrome
Methods The study was approved by the local ethics committee. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent/permission was obtained from all parent participants and child assent from patient participants for being included in the study. Twenty adult patients with RLS (14 females and 6 males) and 20 healthy controls (14 females and 6 males) who were referred to university neurology clinic were enrolled in the present study. Demographic characteristics, including age, gender, education levels, medical history, and drug intake, were recorded. A detailed neurological examination was performed, as well as laboratory tests, including urea, creatinine, liver function, electrolytes, vitamin B12, complete blood count, iron, iron binding capacity, ferritin, and thyroid function. Exclusion criteria included known neurodegenerative and psychiatric disorders, secondary RLS (expected anemia), and uneducated individuals. The study was approved by the local ethics committee. Diagnosis of RLS was established in subjects with suspected RLS using International Restless Legs Syndrome Study Group diagnostic criteria, including (i) urge to move the legs, usually accompanied or caused by uncomfortable leg sensations; (ii) temporary relief with movement, partial or total relief from discomfort by walking or stretching; (iii) onset or worsening of symptoms at rest or inactivity, such as when lying down or sitting; and (iv) worsening or onset of symptoms in the evening or at night (Walters et al., 2003). Psychometric evaluation Each patient underwent psychometric evaluation with the Turkish version of the MMPI (Savas¸ır, 1981; Erol, 1982), which consists of 566 statements answered as “true” or “false,” as applies to the patient. The scoring results in a standard profile that consists of three “validity scales” and ten “personality scales.” The validity scales consist of lie, fake, and defensive responses, and validate each profile. Subjects scoring beyond predetermined limits on these scales have answered the test with bias, invalidating the results of the personality scales. In this study, there are no biased profiles. The personality scales score characteristics that are based on psychodiagnostic categories. They are not considered to be indicators of
154
Y. Turkel et al.
psychopathology per se, but personal characteristics that are somewhat related to the content description of the category. The personality scales consist of hypochondriasis, depression, hysteria, psychopathic deviate, masculinity–femininity, paranoia, psychasthenia, schizophrenia, hypomania, and social introversion. Results of the MMPI test are expressed in standardized t-scores. Thus, a scale score is considered indicative of psychological dysfunction when t-value is >65. We dichotomously classified each individual subject in terms of whether or not each scale fell in the clinically elevated range. Elevation was defined as t-score >65. Absolute scores were mean of standardized t-scores.
Statistical methods All clinical parameters were expressed as mean ± SD, as well as percentages (for categorical variables). Patients with RLS and healthy controls were compared using one-way analysis of variance for continuous parameters, and chi-squared test for categorical parameters. A P-value of 0.05). There was no difference between both groups in terms of gender and education levels (P > 0.05). Table 1 shows the means (SD) and percentage of sample elevated (t > 65) for MMPI clinical scales in patient and control groups. RLS patients have significantly higher absolute scores on hypochondriasis compared with the controls (65.2 ± 10.8 versus 49.6 ± 10.1, P = 0.001). RLS patients have also significantly higher absolute scores on hysteria compared with the controls (64.5 ± 9.2 versus 43.6 ± 7.4, P = 0.001). Absolute scores on depression were higher at the border in RLS patients compared with the controls (55.7 ± 9.7 versus 50.3 ± 7.8, P = 0.05). RLS patients have higher rates of clinical elevation on hypochondriasis, hysteria, and psychasthenia (50.0, P = 0.004; 35.0, P = 0.001; 20.0, P = 0.01, respectively).
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
Y. Turkel et al.
MMPI and restless legs syndrome
Table 1. Means (SD) and percentage of sample elevated (t > 65) for MMPI clinical scales in patients and controls Patients (n = 20)
Controls (n = 20)
MMPI clinical scale
Mean ± SD
% Elevated
Mean ± SD
% Elevated
P-values†
Hypochondriasis Depression Hysteria Psychopathic deviate Masculinity/femininity Paranoia Psychasthenia Schizophrenia Hypomania Social introversion MMPI mean t-score Number of elevations
65.2 ± 10.8 55.7 ± 9.7 64.5 ± 9.2 52.3 ± 10.8 56.4 ± 10.5 52.4 ± 10.4 53.9 ± 8.8 50.9 ± 9.6 51.4 ± 9.7 53.8 ± 12.9 55.6 ± 6.5 1.9 ± 1.6
50.0 20.0 35.0 10.0 20.0 10.0 20.0 10.0 5.0 10.0
49.6 ± 10.1* 50.3 ± 7.8** 43.6 ± 7.4*** 48.9 ± 10.5 59.5 ± 9.0 51.2 ± 10.6 48.1 ± 9.5 47.6 ± 10.3 53.1 ± 7.7 51.9 ± 7.3 50.4 ± 5.4**** 0.8 ± 0.8
10.0 5.0 0 15.0 25.0 5.0 0 5.0 10.0 5.0
0.004 0.13 0.001 0.63 0.7 0.54 0.01 0.54 0.54 0.54
*P = 0.001; **P = 0.05; ***P = 0.001; ****P = 0.009. †Comparison of percentage of sample elevated (t > 65) for MMPI clinical scales. MMPI, Minnesota Multiphasic Personality Inventory. Significant p-values are shown in the italics format.
Discussion This is the first study to examine personality traits in persons with RLS using the MMPI. We found that individuals with RLS had higher hysteria scores than non-RLS controls. Neuroticism is a personality trait characterized by anxiety, moodiness, worry, envy, and grudge. Neuroticism is the tendency to experience negative emotions, such as anger, anxiety, or depression. Neuroticism is sometimes called emotional instability (Thompson, 2008). Histrionic personality disorder (HPD) is defined by the American Psychiatric Association as a personality disorder characterized by a pattern of excessive emotions and attention-seeking, including inappropriately seductive behavior and an excessive need for approval, usually beginning in early adulthood. People affected by HPD are lively, dramatic, vivacious, and enthusiastic (DSM-IV-TR Diagnostic and Statistical Manual of Mental Disorders, 2000). HPD overlaps with neuroticism characterized with emotional instability. Kalaydjian et al. (2009) found that individuals with RLS have higher mean neuroticism factor scores than non-RLS controls. In this study, personality traits were assessed using the revised NEO Personality Inventory. The authors suggested that high neuroticism may be a predisposing factor for RLS, and therefore may mediate the association of RLS with mood and anxiety disorders. Besides, the authors suggested that the sleep deprivation inherent in RLS and impaired quality of life may enhance neuroticism in RLS patients. They also claimed that neuroticism and
Asia-Pacific Psychiatry 7 (2015) 153–156 © 2014 Wiley Publishing Asia Pty Ltd
RLS may result from a similar etiology. This relationship was found to be related with dopamine (Kalaydjian et al., 2009). We believe that similar mechanisms may affect the patients. Another explanation may be as follows. Histrionic personality traits are a situation that there is exaggerated attract attention behavior. Hysteria rate elevation determined in the MMPI may be a reflection of personality traits that complaints were exaggerated in RLS patients admitted to our clinic. The present study indicated that RLS patients had a significantly higher rate of hypochondriasis scores than non-RLS controls. General hypochondriacal complaints were seen with manifestations of a somatization or psychophysiological reaction. Even when or if they had real physical symptoms, patients were found to exaggerate their severity (Bayar et al., 2001). It is possible that the psychopathology might reflect the effects of symptoms secondary to disease more than the direct effects of sleep disturbance per se (Ekici et al., 2013). The present study showed that RLS patients had higher depression absolute scores than non-RLS controls. Previous studies have shown that the risk of depression increases in RLS patients (Rothdach et al., 2000; Sevim et al., 2004). Possible mechanisms of specific depressive symptoms in RLS have not been exactly known. It could be that sleep disturbances may increase the risk of these disorders, and it is well known that sleep disturbances can increase the risk of depressive disorders (Rothdach et al., 2000). High depression scores in RLS may also be related to neuroticism. The present study indicated that RLS patients had a significantly higher rate of psychasthenia clinical
155
MMPI and restless legs syndrome
elevation scores than non-RLS controls. Elevation in psychasthenia clinical elevation scores refers to anxiety disorders (Erol, 1982; Thompson, 2008). Clinical association of RLS and anxiety disorders has also been described (Winkelmann et al., 2005). Gorman et al. (1965) found higher scores on depression and psychasthenia scales in RLS patients than both the general population and psychiatric referrals. The authors suggested that impairment of sleep and chronic sleep deprivation caused by RLS is likely to be the chief cause of anxiety. The present study indicates that hypochondriac, hysteric, depressive, and psychasthenia personality characteristics were exhibited by RLS patients. Clinicians evaluating RLS patients should be aware that the disease may be accompanied by psychological disturbance. References Frances A., Pıncus H.A., First M.B., et al. (2000) Personality disorders. In: First M.B., ed. DSM-IV-TR Diagnostic and Statistical Manual of Mental Disorders. American Psychiatric Publishing, American Psychiatric Association, chapter 16. Bayar N., Oguztürk O., Kazkayasi M., Koç M.C. (2001) Minnesota Multiphasic Personality Inventory profile of patients with chronic sinusitis. Rhinology. 39, 133–135. Brand S., Beck J., Hatzinger M., Holsboer-Trachsler E. (2013) Patients suffering from restless legs syndrome have low internal locus of control and poor psychological functioning compared to healthy controls. Neuropsychobiology. 68(1), 51–58. Chaudhuri K.R., Forbes A., Grosset D., et al. (2004) Diagnosing restless legs syndrome (RLS) in primary care. Curr Med Res Opin. 20, 1785–1795. Chokrovertry S., Jankovic J. (1999) Restless legs syndrome: a disease in search of identity. Neurology. 52, 907–910. Ekici A., Ekici M., Og˘uztürk O., Karabog˘a I., Cimen D., Senturk E. (2013) Personality profiles in patients with obstructive sleep apnea. Sleep Breath. 17, 305–310.
Y. Turkel et al.
and treatment of restless legs syndrome (RLS) in a primary care population: the REST (RLS epidemiology, symptoms and treatment) primary care study. Sleep Med. 5, 237–246. Högl B., Kiechl S., Willeit J., et al. (2005) Restless legs syndrome: a community-based study of prevalence, severity, and risk factors. Neurology. 64, 1920–1924. Kalaydjian A., Bienvenu O.J., Hening W.A., Allen R.P., Eaton W.W., Lee H.B. (2009) Restless legs syndrome and the five-factor model of personality: results from a community sample. Sleep Med. 10, 672–675. Leschziner G., Gringras P. (2012) Restless legs syndrome. BMJ. 344, e3056. Ohayon M.M., Roth T. (2002) Prevalence of restless legs syndrome and periodic limb movement disorder in the general population. J Psychosom Res. 53, 547–554. Phillips B., Young T., Finn L., Asher K., Hening W.A., Purvis C. (2000) Epidemiology of restless legs symptoms in adults. Arch Intern Med. 160, 2137–2141. Picchietti D., Winkelman J.W. (2005) Restless legs syndrome, periodic limb movements in sleep, and depression. Sleep. 28, 891–898. Rothdach A.J., Trenkwalder C., Haberstock J., Keil U., Berger K. (2000) Prevalence and risk factors of RLS in an elderly population. Neurology. 54, 1064–1068. Savas¸ır I. (1981) Minesota Çok Yönlü Kis¸ilik Envanteri-Elkitabı (TürkStandardizasyonu). Sevinç Matbaası, Ankara. Sevim S., Dogu O., Camdeviren H., et al. (2003) Unexpectedly low prevalence and unusual characteristics of RLS in Mersin, Turkey. Neurology. 6, 1562–1569. Sevim S., Dogu O., Kaleagasi H., Aral M., Metin O., Camdeviren H. (2004) Correlation of anxiety and depression symptoms in patients with restless legs syndrome: a population based survey. J Neurol Neurosurg Psychiatry. 75, 226–230. Thompson E.R. (2008) Development and validation of an international English big-five mini-markers. Pers Individ Dif. 45, 542–548.
Erol N. (1982) Ülkemizde Psikiyatrik Hastalarda Minnesota Çok Yönlü Kis¸ilik Envanterinin Geçerlik Aras¸tırması. DTCF Psikoloji Kürsüsü, Doktora Tezi. AÜ.
Walters A.S., LeBrocq C., Dhar A., et al. (2003) Validation of the International Restless Legs Syndrome Study Group rating scale for restless legs syndrome. Sleep Med. 4, 121–132.
Gorman C.A., Dyck P.J., Pearson J.S. (1965) Symptoms of restless legs. Arch Intern Med. 115, 155–160.
Winkelmann J., Prager M., Lieb R., et al. (2005) “Anxietas tibiarum”. Depression and anxiety disorders in patients with restless legs syndrome. J Neurol. 252, 67–71.
Hening W., Walters A.S., Allen R.P., Montplaisir J., Myers A., Ferini-Strambi L. (2004) Impact, diagnosis
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