Method: A total of 272 inpatients with at least one major depressive episode, with or without a history of a suicide attempt, were entered into the study. They were.
Article
Anxiety in Major Depression: Relationship to Suicide Attempts Giovanni P.A. Placidi, M.D. Maria A. Oquendo, M.D. Kevin M. Malone, M.D. Beth Brodsky, Ph.D. Steven P. Ellis, Ph.D. J. John Mann, M.D.
Objective: This study was an examination of the relationship of lifetime panic disorder and anxiety symptoms at index hospitalization to a history of a suicide attempt in patients with a major depressive episode. Method: A total of 272 inpatients with at least one major depressive episode, with or without a history of a suicide attempt, were entered into the study. They were given structured diagnostic interviews for axis I and axis II disorders. Suicide attempt history, current psychopathology, and traits of aggression and impulsivity were also assessed.
Results: The rates of panic disorder did not differ in the suicide attempters and nonattempters. Agitation, psychic anxiety, and hypochondriasis were more severe in the nonattempter group. A multivariate analysis confirmed that this effect was independent of aggression and impulsivity. Conclusions: Comorbid panic disorder in patients with major depression does not seem to increase the risk for lifetime suicide attempt. The presence of greater anxiety in the nonattempters warrants further investigation. (Am J Psychiatry 2000; 157:1614–1618)
P
anic disorder and anxiety symptoms are hypothesized risk factors for suicidal behavior. However, studies of the relationship of suicidal acts to anxiety in either the presence or absence of major depression have yielded conflicting results. Some studies have indicated that patients with panic disorder have the same rates of suicide as patients with major depression (1, 2). Others have shown a lower incidence of suicide in “pure” panic disorder (3–5). One reason for the discrepancy among results in the literature may lie in the failure of studies with smaller, convenience samples to take into account other factors that predispose patients to suicidal behavior. Such factors include comorbid mood disorders, traits of aggressivity and impulsivity, a family history of suicidal acts, and comorbid substance abuse or alcoholism. For example, in a study of patients with panic disorder (6), patients with a history of depression had a higher rate of attempted suicide than the patients without depression (70.6% versus 29.4%). However, this study did not evaluate other putative risk factors, such as axis II disorders and lifetime traits such as aggression and impulsivity. The aim of the present study was to determine whether panic disorder or anxiety symptoms are associated with a history of suicidal behavior in depressed inpatients, by using both a categorical diagnosis and dimensional measures of anxiety. To this end, structured clinical interviews were used to determine axis I and II diagnoses. Moreover, lifetime aggression and impulsivity, known correlates of suicidal behavior (7), were also measured.
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Method Subjects The study participants were 272 patients aged 17–72 years who were admitted to a university psychiatric hospital for the treatment of mood disorders. All patients gave written informed consent as approved by the Institutional Review Board. Each patient had a history of at least one major depressive episode and met the DSM-III-R criteria for major depression or bipolar disorder. The patients had no active medical or neurological problems or current alcohol or substance abuse.
Measures DSM-III-R axis I and II disorders were diagnosed by using the Structured Clinical Interview for DSM-III-R (SCID) for axis I (8) and axis II (9) disorders. Psychiatric symptoms were rated with the 24-item Hamilton Depression Rating Scale (10), the Brief Psychiatric Rating Scale (BPRS) (11), and the Beck Depression Inventory (12). The items for agitation, psychic anxiety, somatic anxiety, and hypochondriasis from the Hamilton depression scale and the items for anxiety, somatic concern, and tension from the BPRS were used to measure the presence of anxiety symptoms. Lifetime aggression and impulsivity were rated by using the Brown-Goodwin Aggression Inventory (13) and the Barratt Impulsivity Scale (14), respectively. A suicide attempt was defined as a self-destructive act carried out with at least some intent to end one’s life. The Scale for Suicidal Ideation (15) was used to measure suicidal ideation during the 2 weeks before hospitalization. The subject’s intent to die at the time of the attempt was assessed by using the Suicide Intent Scale (16). The lethality or medical damage inflicted by suicide attempts was measured with the Medical Damage Rating Scale (16). The raters each had a master’s or doctorate degree and had met our previously reported criteria for reliability (7). Am J Psychiatry 157:10, October 2000
PLACIDI, OQUENDO, MALONE, ET AL.
Statistical Analyses Chi-square analyses and Student’s t tests were used to contrast attempters and nonattempters. Fisher’s exact test was used to compare the rates of panic disorder and borderline personality disorder diagnoses in the two groups when the expected counts in some cells were not sufficiently high. A multivariate analysis of variance for Hamilton depression scale anxiety symptoms and BPRS anxiety symptoms by attempter status was performed. All statistical tests were two-tailed.
Results Of the total subjects, 143 (52.6%) had attempted suicide and 129 (47.4%) had not. The two subgroups did not differ on demographic characteristics (data available on request). The mean age of the entire study group was 35.2 years (SD=11.7); 42.6% were male (N=116), and 77.9% were Caucasian (N=212). One-third of the subjects (34.2%, N=93)—more than one-half of the attempter group—had made multiple suicide attempts. At least one comorbid diagnosis was identified in 42.6% of the study group (N=116). The suicide attempters and nonattempters differed significantly in the numbers with axis I and axis II comorbid disorders; both were more common among the attempters (Table 1). Panic disorder was present in 26 subjects (9.6%; four men and 22 women). The attempters did not differ significantly from the nonattempters in lifetime rate of panic disorder (Table 1). The attempters scored higher on subjective depression (Beck Depression Inventory) than the nonattempters, but they did not differ in severity of objective depression (Hamilton depression scale total) or general psychopathology (BPRS total) (Table 2). The mean score for anxiety items on the Hamilton depression scale was higher in the nonattempter group, and there were significant differences for agitation, psychic anxiety, and hypochondriasis (Table 2). The BPRS mean score for anxiety was also higher in the nonattempter group, and there were significant differences for the somatic concern and anxiety items (Table 2). A Hotelling T2 test multivariate comparison of the attempters and nonattempters indicated significant differences between groups for the Hamilton scale anxiety symptoms (F=2.78, df=4, 260, p=0.03), the BPRS anxiety symptoms (F=5.03, df=3, 255, p=0.002), and the Brown-Goodwin Aggression Scale and Beck Depression Inventory scores (F=18.70, df=2, 202, p=0.001). Thus, the mean scores for anxiety and the combination of aggressivity and subjective depression were significantly different in the attempters and nonattempters (also see Table 2). After adjustment for panic disorder and anxiety measures, a logistic regression of suicide attempter status on aggressivity showed that aggressivity was still highly predictive of attempter status (likelihood ratio test: χ2=28.71, df=1, p
