A cluster analysis-derived classification of psychological distress and illness behavior in the medically ill.
BACKGROUND
The classification of psychological distress and illness behavior in the setting of medical disease is still controversial. Current psychiatric nosology does not seem to cover the spectrum of disturbances. The aim of this investigation was to assess whether the joint use of DSM-IV categories and the Diagnostic Criteria for Psychosomatic Research (DCPR), that provide identification of syndromes related to somatization, abnormal illness behavior, irritable mood, type A behavior, demoralization and alexithymia, could yield subtyping of psychosocial variables in the medically ill.


METHODS
A cross-sectional assessment using both DSM-IV and the DCPR was conducted in eight medical centers in the Italian Health System. Data were submitted to cluster analysis. Participants were consecutive medical out-patients and in-patients for whom a psychiatric consultation was requested. A total of 1700 subjects met eligibility criteria and 1560 agreed to participate.


RESULTS
Three clusters were identified: non-specific psychological distress, irritability and affective disturbances with somatization.


CONCLUSIONS
Two-step cluster analysis revealed clusters that were found to occur across clinical settings. The findings indicate the need of expanding clinical assessment in the medically ill to include the various manifestations of somatization, illness behavior and subclinical distress encompassed by the DCPR.
Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy.
G A
GA
Fava
Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy.
J
J
Guidi
Psychosomatic Unit, IRCCS De Bellis Hospital, Castellana Grotte, Bari, Italy.
P
P
Porcelli
Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy.
C
C
Rafanelli
Section of Psychiatry and Clinical Psychology, Department of Medical Sciences, University of Foggia, Foggia, Italy.
A
A
Bellomo
Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy.
S
S
Grandi
Section of Psychiatry, Department of Medical Sciences of Communication and Behavior, University of Ferrara, Ferrara, Italy.
L
L
Grassi
Laboratory of Psychosomatics and Clinimetrics, Department of Psychology, University of Bologna, Bologna, Italy.
L
L
Mangelli
Clinical Epidemiology Unit, Istituto Dermapatico dell'Immacolata (IDI-IRCCS), Roma, Italy.
P
P
Pasquini
Mental Health Unit, Italian National Institute of Health Center of Epidemiology, Surveillance and Health Promotion, Roma, Italy.
A
A
Picardi
Section of Psychiatry, Clinical Psychology and Psychiatric Rehabilitation, Department of Clinical and Experimental Medicine, University of Perugia, Perugia, Italy.
R
R
Quartesan
Department of Neuroscience, University of Modena and Reggio Emilia, Modena, Italy.
M
M
Rigatelli
Department of Psychiatry, State University of New York at Buffalo, Buffalo, NY, USA.
N
N
Sonino
D000328:Adult; D002908:Chronic Disease / Q000523:psychology*; D016000:Cluster Analysis; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D055809:Illness Behavior / Q000145:classification*; D007508:Irritable Mood / Q000145:classification; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000145:classification*; D011569:Psychiatric Status Rating Scales; D013001:Somatoform Disorders / Q000145:classification* / Q000175:diagnosis; D013315:Stress, Psychological / Q000145:classification* / Q000175:diagnosis; D013577:Syndrome; D014434:Type A Personality