The psychiatric profile of chronic pruritus patients
Oğuz Akman1, Fatma Özlem Orhan2, Perihan Öztürk3, Ali Özer4, Yasemin Akman5, Mehmet Fatih Karaaslan61 M.D., Kahramanmaraş Necip Fazıl City Hospital, Department of Psychiatry, Kahramanmaraş, Turkey
2 Assoc. Prof. Dr., 6Prof., Dr., Kahramanmaraş Sütçü İmam University Medical Faculty, Department of Psychiatry, Kahramanmaraş,
Turkey
3 Assoc. Prof. Dr., Kahramanmaraş Sütçü İmam University Medical Faculty, Department of Dermatology, Kahramanmaraş, Turkey 4 Assoc. Prof. Dr., Malatya İnönü University Medical Faculty, Department of Public Health, Malatya, Turkey
5 M.D., Kahramanmaraş Necip Fazıl City Hospital, Department of Dermatology, Kahramanmaraş, Turkey
Corresponding Author:
Oğuz Akman, M.D., Kahramanmaraş Necip Fazıl City Hospital, Department of Psychiatry, Kahramanmaraş Phone: +903442235332 - E-mail: oguzakm@hotmail.com
Geliş Tarihi/Date of Receipt: 17 Şubat 2015 - Kabul Tarihi/Date of Acceptance: 06 April 2015
ÖZET
Kronik Pruritus hastalarında psikiyatrik profil
Amaç: Kaşıntı ya da pruritus, kaşıma isteğine neden
olan rahatsızlık verici duyu olup, deri hastalıkları için-de en sık görülen semptomdur. Kronik pruritus, birçok deri ve sistemik hastalıklarda görülebildiği gibi psikiyat-rik bozukluklarda da görülebilmektedir. Bu çalışmadaki amaç, birincil deri hastalıkları ve kaşıntıya sebep olabi-lecek sistemik hastalıkların hariç tutulduğu kronik pru-rituslu hastalarda kaşıntının özelliklerinin, eşlik eden psikiyatrik bozuklukların ve depresif belirtilerin araştı-rılmasıdır.
Yöntem: Çalışmamıza 126 kronik prurituslu hasta
alındı. Hastaların sosyodemografik verilerini ve hasta-lığıyla ilgili özelliklerini içeren form dolduruldu. DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders-IV-Text Revision) tanı ve değerlendirme sis-temine göre SCID-I/CV (Structered Clinical Interview for DSM-IV, Clinical Version) uygulanarak psikiyatrik tanılar araştırıldı. Beck Depresyon Envanteri (BDE) uygulandı.
Bulgular: Kronik prurituslu hastaların % 70,6’sında 1 ile
3 arasında değişen sayılarda psikiyatrik bozukluk sap-tandı. En sık görülen psikiyatrik bozukluklar ise % 34,1 ile depresif bozukluklar olarak tespit edilmiştir. Psiki-yatrik tanı alan grupta yaygın kaşıntı ve BDE puanları, psikiyatrik tanı almayan gruba göre anlamlı derecede yüksek saptandı (p<0,05). Tüm kronik prurituslu hasta-ların % 62’sinde hafiften şiddetliye değişen oranlarda depresif belirtiler saptandı.
Sonuçlar: Birincil deri ve sistemik hastalığı
saptanama-yan kronik prurituslu hastalarda yüksek oranda
psi-kiyatrik bozuklukların görülmesi ve özellikle depresif belirtilerin eşlik etmesi, bu hastalarda psikiyatrik değer-lendirmenin önemine işaret etmektedir.
Anahtar sözcükler: Kronik pruritus, psikiyatrik
bozuk-luk, depresif belirtiler
ABSTRACT
Objective: Itching, or pruritus, is an uncomfortable
sen-sation leading to the urge to scratch, and it is the most common symptom in skin diseases. Chronic pruritus may be seen in many skin and systemic diseases as well as in psychiatric disorders. The aim of the present study was to investigate itching features, psychiatric disorders, and depressive symptoms of patients with chronic pruritus due to reasons other than primary skin diseases or systemic diseases that may cause itching.
Methods: 126 patients with chronic pruritus were
included in the study. Sociodemographic data and disease-related features were recorded on a form. Psychiatric diagnoses were established based on the Diagnostic and Statistical Manual of Mental Disor-ders-IV-Text Revision (DSM-IV-TR) criteria, using the Structured Clinical Interview for DSM-IV, Clinical Ver-sion (SCID-I/CV). The Beck DepresVer-sion Inventory (BDI) was applied.
Results: Of the chronic pruritus patients, 70.6% had
psychiatric disorders ranging from one to three. The most common psychiatric disorders were depressive disorders, with a rate of 34.1%. The generalized itch-ing and BDI scores were significantly higher in patients with a psychiatric diagnosis as compared to those with-out (p<0.05). Among all chronic pruritus patients, 62%
had depressive symptoms ranging from mild to severe.
Conclusions: The high rate of psychiatric disorders,
particularly the presence of concomitant depressive symptoms, in patients with chronic pruritus without a primary skin or systemic disease indicates the impor-tance of psychiatric assessment in such patients.
Key words: Chronic pruritus, psychiatric disorder,
de-pressive symptoms
INTRODUCTION
The most common symptom of skin disease, itching, or pruritus, can be defined as an uncomfortable sensation that causes scratching.1 Pruritus can be referred to as
localized or generalized based on its distribution.2
Al-though it can be seen in normal skin, secondary chang-es such as excoriations, lichenification, or prurigo can also accompany it.3 While there is no internationally
recognized classification for itching, in recent years, progress has been made in this regard and there are some classifications available.
Twycross et al.4 developed an itching classification
based on mediators in which they classified itching as pruritoceptive, neuropathic, neurogenic, or psychogen-ic. According to the International Forum for the Study of Itch, clinical classification was divided into three main groups based on the status of skin in chronic pru-ritus: itching in the primary inflammatory skin, itching in normal skin, and skin with secondary itching lesions. With clinical and laboratory evaluation, these three main groups were divided into six subgroups accord-ing to the etiologic classification (dermatological, sys-temic, neurological, psychiatric, mixed and others).5 In
a broad participation study conducted in Italy, a signif-icant psychiatric morbidity rate was observed in pruri-tus patients.6
Itching is a complex mechanism that is not fully under-stood. Both peripheral and central mechanisms play a role in the condition. In the formation of pruritus, the mediators such as histamine, serotonin, bradykinin, neuropeptide substance P, endothelin, and proteases have important roles, especially in central pruritus opi-oid peptides.7 Since the role of the brain has been
re-vealed in the pathogenesis of pruritus, this shows that psychogenic factors have an effect on all types of pru-ritus, and pruritus cases caused by psychogenic factors only have also been observed.8
latter defined as pruritus lasting six or more weeks.5
Chronic pruritus can persist for months or even years, can reoccur after the termination of treatment, can have effects on the social life and the quality of life of the patient, and can be due to psychiatric disorders as well as dermatological diseases, systemic reasons, and pathologies in the nervous system.9,10 If itching has
an organic origin, verified with physical examination results and laboratory analysis, patients are sent to a dermatology department or another relevant depart-ment. However, in itching associated with psychiatric disorders, drawing the diagnostic boundaries can be more difficult. If a chronological relationship can be demonstrated between the beginning of itching and the psychiatric disorder, then diagnosis can be easier.1
Psychogenic pruritus cannot be explained by organic reasons, is triggered by psychological factors,11 and can
involve psychiatric disorders such as depressive disor-der, anxiety disordisor-der,1 or basically neurotic excoriations
and delusional parasitosis.12
There can be many psychiatric reasons for itching,9
therefore psychiatric disorders should be considered. If no organic etiology of pruritus can be found, then the itching is identified as idiopathic pruritus. The aim of the present study was to investigate itching features, psychiatric disorders, and depressive symptoms of pa-tients with chronic pruritus due to reasons other than primary skin diseases or systemic diseases that may cause itching.
MATERIALS AND METHODS
Permission and approval was granted before the study by the Clinical Research Ethics Committee of Erciyes University. Informed consent was given by all the pa-tients. This study was conducted with chronic pruritus patients suffering from itching for six weeks or longer, in a specific area or affecting the whole body, and who were accepted for evaluation by a dermatologist in the dermatology outpatient unit of Kahramanmaras Sutcu Imam University Hospital. Patients who were between the ages of 18 and 65, who were able fill in the study forms, and who agreed to participate in the study were included. Pregnancy; primary skin diseases (e.g., atopic dermatitis, psoriasis, urticaria, bullous diseases, neo-plastic diseases, hereditary, or congenital diseases) and systemic diseases (e.g., chronic renal failure, primary biliary cirrhosis, acute and chronic hepatitis, cholesta-sis, iron deficiency anemia, polycythemia vera,
multi-hyperthyroidism) that can cause itching; mental retar-dation; and dementia were defined as exclusion crite-ria. Patients who were assessed as normal in terms of primary skin and systemic diseases that can cause itch-ing through history, physical examination, and labora-tory investigations were included. Patients using drugs that may cause itching were excluded from the study.
Information form: This form includes
sociodemo-graphic characteristics, disease-related information, and pruritus score.
Duration of pruritus, localization of itching, and status of the skin were evaluated by a dermatologist. Itching localization was specified as general, face, scalp, trunk, extremities, or genitals or anal region. The status of the skin was classified as normal, excoriation, lichen simplex chronicus, or prurigo nodularis. Patients were asked to assess their itching score by marking their itching severity on a visual scale from 0 to 10.
Structured Clinical Interview for DSM-IV, Clinical Ver-sion (SCID-I/CV): The SCID-I, developed by First and his
colleagues,13 is a reliable and valid assessment tool for
the evaluation of Axis I disorders according to DSM-IV. Reliability and validity analyses of the Turkish form were performed by Özkürkçügil et al..14
Beck Depression Inventory (BDI): The BDI is a 21-item
self-report questionnaire that assesses the severity of depression. Individuals are asked to rate themselves on a 0–3 spectrum (0 = least, 3 = most) with a score range of 0 to 63. The total score is the sum of all items. The inventory, developed by Beck et al. in 1961,15 was
shown to be valid and reliable in a Turkish sample.16,17
Statistical evaluation: For statistical analysis of the
data obtained in this study, Statistical Package for So-cial Sciences (SPSS) for Windows 15.0 was used. A chi-square test was used for discrete variables; and for comparisons of continuous variables, according to the parametric conditions, a Mann-Whitney U test or Stu-dent’s t-test was used. In the Kolmogorov-Smirnov test, itching time was not in accordance with the normal dis-tribution (p<0.05). In all evaluations, p<0.05 was consid-ered significant.
RESULTS
In 691 patients diagnosed with chronic pruritus; 502
were excluded from the study due to primary skin dis-eases and 56 were excluded due to systemic disdis-eases that can cause itching, and one patient was excluded due to pregnancy. Six patients from the remaining 132 did not consent to participate. A total of 126 patients were accepted to the study.
Sociodemographic characteristics: Chronic pruritus
patients included in the study were between the ages of 18 and 65, with a mean of 42.62 ± 12.05 years. Pa-tients were grouped in terms of gender, marital status, education level, job, place of residence, economic in-come level, habits, and psychiatric applications (Table 1).
Psychiatric disorders and depression scores: Using
DSM-IV-TR diagnostic criteria, the assessment showed that there were no psychiatric diagnoses in 37 pa-tients (29.4%), and psychiatric diagnoses were present in numbers varying from one to three in 89 patients (70.6%). Of the psychiatric diagnoses, depressive disor-ders were seen at the highest rate (34.1%) (Table 2). In patients with chronic pruritus, there were no statisti-cally significant differences with regard to age, gender, age at onset of pruritus, duration of pruritus, and pruri-tus score between patients with psychiatric diagnoses and those without (p> 0.05). In distribution of itching localization, generalized itching was significantly higher in the group with psychiatric diagnoses than the group without (p<0.05). BDI scores in the group with psychi-atric diagnoses was significantly higher than the group without psychiatric diagnoses (p<0.05) (Table 3). 78 chronic pruritus patients (62%) showed mild to severe depressive symptoms in varying proportions according to the BDI scores (Table 4).
The average itching score of chronic pruritus patients was 5.94 ± 2.59. In patients with chronic pruritus, there were no statistically significant correlation between itching score and BDI score.
Clinical features: While 36 (40.4%) chronic pruritus
pa-tients diagnosed with psychiatric disorders had gener-alized itching, the other 53 patients (59.6%) had local-ized itching. In addition, 51 patients (57.3%) had no skin lesions, and 38 patients (42.7%) had secondary skin lesions. The distribution of itching localization, lesion status, and duration of itching in the chronic pruritus patients with psychiatric diagnoses are summarized in Table 5.
Table 1: Sociodemographic characteristics of chronic pruritus patients Scores % Gender Female Male 93 33 73.8 26.2
Age (mean ± SD year) 42.62±12.05
Marital status Married Single Widowed/Divorced 102 11 13 81 8.7 10.3 Educational level Literate Elementary school Secondary school High school University 30 49 18 16 13 23.8 38.9 14.3 12.7 10.3 Job Officer Worker Housewife Unemployed Retired Self-employed Student 9 17 65 13 14 5 3 7.1 13.5 51.6 10.3 11.1 4 2.4 Place of residence Village District City 13 8 105 10.3 6.4 83.3
Level of economic income
0–499TL 500–999TL 1000–1499TL 1500–↑TL 78 24 10 14 61.9 19.1 7.9 11.1 Habits Cigarettes Alcohol Maraş powder Drugs
Cigarettes + Alcohol + Maraş powder No habits 21 0 8 0 1 96 16.7 0 6.4 0 0.8 76.1
Table 2: Psychiatric assessment results of chronic pruritus patients*
Psychiatric diagnoses Number %
Mood disorders
Major depressive disorder Dysthymic disorder Depressive disorder, NOS Bipolar I disorder 32 6 5 1 25.3 4.8 4 0.8 Anxiety disorders Generalized anxiety disorder Obsessive compulsive disorder Panic disorder, with agoraphobia Panic disorder, without agoraphobia Specific phobia Social phobia
Anxiety disorder, NOS
13 10 3 1 3 3 3 10.3 7.9 2.4 0.8 2.4 2.4 2.4
Schizophrenia and other psychotic disorders
Schizophrenia
Psychotic disorder, NOS
1 1 0.8 0.8 Somatoform disorders Somatization disorder Undifferentiated somatoform disorder Body dysmorphic disorder
1 41 4 0.8 32.5 3.2 Adjustment disorders 4 3.2
* Some of the patients were diagnosed with more than one psychiatric disorder ** NOS: not otherwise specified
Table 3: Comparison of age, gender, age at onset of pruritus, duration of pruritus, localization of pruritus,
pruri-tus score and BDI point in chronic pruripruri-tus patients with psychiatric diagnoses and without psychiatric diagnoses
Diagnosed with psychiatric disorder (n: 89)
Not diagnosed with a
psychiatric disorder (n: 37) p
Age (mean ± SD year) 42.91±11.63 41.92±13.13 0.676
Gender (female/male %) 77.5/22.5 64.9/35.1 0.141
Age at onset of pruritus
(mean ± SD year) 37.56±12.3 38.73±13.56 0.639
Duration of pruritus (month)
(min-med-max) 1.50-24-324 2-24-240 0.125
Localization of pruritus
(generalized/localized %) 40.4/59.6 21.6/78.4 0.043
Pruritus score (mean ± SD) 5.89±2.49 6.05±2.85 0.744
BDI score (mean ± SD) 15.29±8.43 8.7±4.25 <0.001
*n: number; SD: standard deviation; BDI: Beck Depression Inventory Min: Minimum, Med: Median, Max: Maximum
Table 4: BDI scores of chronic pruritus patients
BDI Number %
0–9 48 38
10–16: Mild depressive symptoms 39 31
17–29: Moderate depressive symptoms 34 27
30–63: Severe depressive symptoms 5 4
Table 5: Distribution of itching localization, lesion status, and duration of itching in chronic pruritus patients with psychiatric diagnoses Localization Number % General 36 40.4 Face 4 4.5 Scalp 4 4.5 Trunk 23 25.9 Extremity 17 19.1
Genital or anal region 5 5.6
Lesion status
Normal 51 57.3
Excoriation 22 24.7
Lichen simplex chronicus 9 10.1
Prurigo nodularis 7 7.9 Duration 1 year or less 29 32.6 1–5 years 30 33.7 5 years or more 30 33.7 DISCUSSION
There have been several studies that have attempted to determine the relationship between pruritus with primary cutaneous and systemic diseases. Although few studies have attempted to identify the relationship between psychiatric factors, this has been the focus of attention in recent years. Most of these studies consist-ed of screening previous files and records. The aim of our study was to address this issue by investigating the relationship between itching and psychiatric disorders. In skin homeostasis and diseases, the relationship be-tween the peripheral and central nervous system play an important role.18 Moreover, the relationship
be-tween itching and the nervous system is also known.1 It has also been demonstrated that the underlying reason of itching can be psychological.19 In our study,
the presence of psychiatric disorders in patients with chronic pruritus was studied using a structured clinical interview method.
There are limited data on psychiatric disorders in chronic pruritus patients in which primary skin diseas-es or systemic diseasdiseas-es that may cause itching are ex-cluded. In a study by Mazeh et al.,20 32% of the
psychi-atric patients were found to have itching. In a study by Kretzmer et al.,21 idiopathic pruritus was experienced
by 42% of psychiatric inpatients. Chronic itching is a common symptom of skin diseases, systemic diseas-es and psychiatric disorders.22 In our study, psychiatric
disorders of chronic pruritus patients without prima-ry skin diseases and systemic diseases that can cause itching were identified at a rate of 70.6%. In the study by Schneider et al.23 on dermatology patients with chronic
itch, the psychiatric disorder rate was identified at over 70%. Psychiatric factors should be considered in pa-tients presenting with pruritus, because of the high rate of psychiatric disorders in chronic pruritus patients and pruritus can be a symptom of psychiatric disorders. In our study, depressive disorders were detected in 34.1% of the patients, undifferentiated somatoform disorder was detected in 32.5% of the patients, and anxiety
disorders were identified in 28.6% of the patients. In our study, among depressive disorders, major depres-sive disorder was the most common (25.3%); among anxiety disorders, generalized anxiety disorder (10.3%) and obsessive compulsive disorder (7.9%) were identi-fied as common. However, prior psychiatric application was only 16.7%. In our study, depressive disorders and anxiety disorders, except for somatoform itching, were the most common psychiatric disorders among chronic pruritus patients.
In our study, the duration of pruritus symptoms ranged from six weeks to 27 years. In a study by Kılınç et al.,24
the duration of pruritus symptoms ranged from 15 days to 30 years. Thus, the duration of pruritus has a long range. In our study, psychiatric disorders were identified in the patients with both the short- and long-term itching.
In our study with chronic pruritus patients, the gener-alized itching rate was higher in people with psychiatric diagnoses than in those without them. In a study by Aras et al.,25 psychogenic pruritus was identified among
the most common causes of generalized pruritus. In a study by Ferm et al.,3 problems with itching of the
scalp and face were higher in patients with psychiat-ric disorders than in the patients without them. In our study, in the group with psychiatric diagnoses, gener-alized pruritus was observed more frequently than the subgroup of localized pruritus. Localized pruritus was also frequently observed in the trunk (25.9%), and least frequently observed in the face (4.5%) and the scalp (4.5%).
Of the psychosocial constructs, depression and anxiety were significantly associated with the lifetime preva-lence of chronic pruritus.26 In most studies, the
prev-alence ratios of anxiety and depression (up to 16.7%) were investigated, showing moderate to severe de-pression in 10–13% of the dermatology outpatients and 20–23% of the dermatology inpatients with pru-ritus.23 In our study, 31% of the patients showed mild
depressive symptoms, and 31% of the patients showed moderate to severe depressive symptoms. The level of depressive symptoms in the chronic pruritus patients with psychiatric diagnoses was higher than the group without psychiatric diagnoses. In a study by Shee-han-Dare et al.,27 depressive symptoms in patients with
generalized pruritus were higher than in the control group, which demonstrates that depressive symptoms
play an important role in the psychiatric assessment of chronic pruritus patients.
As previously mentioned, secondary skin lesions have been observed due to chronic pruritus.5 In our study,
patients are divided into groups according to the status of the skin lesions. Skin lesions were not observed in more than half of the patients with psychiatric disorders (57.3%) in our study; in 24.7% of the patients, excoria-tions were detected. Skin lesion in the form of excori-ations was observed in most of the patients with ob-sessive compulsive disorder. The interaction between chronic pruritus and psyche is complex. Neurotic ex-coriations may be a form of impulse control disorder.28
In our study, lichen simplex chronicus was identified in 10.1% of the patients with psychiatric disorders. In li-chen simplex chronicus, for which the main reason for itching has not been conclusively determined, various psychiatric disorders, such as major depressive dis-order, obsessive compulsive disdis-order, posttraumatic stress disorder, social phobia, and somatization disor-der can be detected.29 In a study by Konuk et al.,30
de-pression and dissociation scores in patients with lichen simplex chronicus were higher compared with the nor-mal population. The etiology of prurigo nodularis has not been determined clearly; however, psychiatric dis-orders are argued to be the most important cause.31
In our study, prurigo nodularis was identified in 7.9% of patients with psychiatric disorders. In a study of 46 patients with prurigo nodularis, psychosocial disor-ders were recorded in more than 50% of the patients,32
which shows that psychiatric factors play an important role in secondary skin lesions.
Unlike other physical diseases, the quickly noticability of skin diseases at first sight is important for the psyc-hiatric point of view. Because psycpsyc-hiatric and dermato-logical diseases often accompany each other, especial-ly in psychodermatological diseases, those in these two fields of study should work in close cooperation to pro-vide a holistic perspective. In our study, the high rate of psychiatric disorders and, particularly, the presence of concomitant depressive symptoms in patients with chronic pruritus without a primary skin or systemic dis-ease indicate the importance of psychiatric assessment in such patients. New studies, including psychiatric as-sessment in chronic pruritus patients, will contribute to the limited amount of research that has been per-formed in this area.
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