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MEASURING ANXIETY IN PATIENTS WITH BIPOLAR DEPRESSION
May 2020 | Vol. 32 No. 2 | Annals of Clinical Psychiatrye2
ANNALS OF CLINICAL PSYCHIATRY 2020;32(2):e2-e8 RESEARCH ARTICLE
BACKGROUND: DSM-5 introduced the anxious distress specifier in recogni-
tion of the significance of anxiety in patients who are depressed. Studies
have supported the validity of the specifier in patients with major depres-
sive disorder (MDD). In this report from the Rhode Island Methods to
Improve Diagnostic Assessment and Services (MIDAS) project, we exam-
ined the validity of the specifier in patients with bipolar depression.
METHODS: Forty-nine patients with a principal diagnosis of bipolar
depression and 369 with MDD were evaluated with semi-structured
diagnostic interviews, including the DSM-5 Anxious Distress Specifier
Interview (DADSI). The patients were rated on measures of depression,
anxiety, and irritability, and completed self-report measures.
RESULTS: The majority of patients with bipolar depression met the DSM-5
anxious distress specifier, no different than the frequency in patients with
MDD. The DADSI was significantly correlated with other measures of anx-
iety, and more highly correlated with other measures of anxiety than with
measures of depression and irritability. Patients with panic and general-
ized anxiety disorder scored higher on the DADSI than patients without
an anxiety disorder.
CONCLUSIONS: The results of our study indicate that anxious distress is
common in patients with bipolar depression and support the validity of
the DSM-5 anxious distress specifier.
DSM-5 anxious distress specifier in patients
with bipolar depression
CORRESPONDENCE
Mark Zimmerman, MD
Brown Medical School
146 West River Street
Providence, RI 02904 USA
E-MAIL
mzimmerman@lifespan.org
Mark Zimmerman, MD
Sophie Kerr, BA
Caroline Balling, BS
Reina Kiefer, BA
Kristy Dalrymple, PhD
Department of Psychiatry and
Human Behavior
Brown Medical School
Rhode Island Hospital
Providence, Rhode Island, USA
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ANNALS OF CLINICAL PSYCHIATRY
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INTRODUCTION
Anxiety disorders are common in individuals with bipolar
disorder.1-5 Compared with patients with bipolar disorder
without anxiety, patients with bipolar disorder with high
levels of anxiety or a comorbid anxiety disorder are char-
acterized by higher levels of suicidal ideation and history
of suicide attempts,6,7 poorer quality of life,8,9 greater health
care utilization,10 reduced medication compliance,11 poorer
outcome,12-19 and greater chronicity.18-20 An analogous lit-
erature exists for major depressive disorder (MDD).21 In
recognition of the clinical significance of anxiety in patients
who are depressed, DSM-5 added the anxious distress spec-
ifier as a method of subtyping bipolar depression and MDD.
Several recent studies have supported the validity of
the specifier in patients with MDD. Most of these studies did
not use measures that were designed to assess the criteria
of the DSM-5 specifier, but instead these studies approxi-
mated the DSM-5 criteria from scales that were part of an
already existing database.22-26 In some of these studies, not
all the criteria were assessed,24-26 and in other studies the
authors noted that some of the proxy items may not have
been accurate representations of the DSM-5 criterion.22,23
However, 2 recent studies used interviews that were
designed to assess the DSM-5 criteria, and both supported
the validity of the specifier in patients with MDD.21-27
In this report from the Rhode Island Methods to
Improve Diagnostic Assessment and Services (MIDAS)
project, we examined the prevalence and correlates of the
DSM-5 anxious distress specifier in patients with bipolar
depression. We compared the frequency of anxious dis-
tress diagnoses and symptoms in patients with a principal
diagnosis of bipolar depression and MDD. We examined
the specifier’s psychometric properties, its convergent and
discriminant validity, and its association with the diagnosis
of anxiety disorders. We hypothesized that the anxious dis-
tress specifier would be more highly correlated with other
indices of anxiety than nonanxiety symptom domains, and
that patients with an anxiety disorder would score higher on
the measure of anxious distress than patients with bipolar
depression who were not diagnosed with an anxiety disorder.
METHODS
The study was conducted in the Rhode Island Hospital
Department of Psychiatry partial hospital program, a
5-day-per-week intensive treatment program. Patients
meet with a psychiatrist and therapist daily and attend 4
groups per day. The average length of stay is 7.5 days (stan-
dard deviation [SD] = 4.8).
Forty-nine patients with a principal diagnosis of
DSM-IV/DSM-5 bipolar depression (27 patients with
bipolar I and 22 patients with bipolar II) and 369 patients
with a principal diagnosis of MDD presenting for an intake
evaluation at the Rhode Island Hospital Department of
Psychiatry partial hospital program were interviewed by a
trained diagnostic rater who administered the Structured
Clinical Interview for DSM-IV (SCID).28 The SCID was sup-
plemented with questions from the Schedule for Affective
Disorders and Schizophrenia (SADS)29 assessing the
severity of symptoms and psychosocial functioning during
the week prior to the evaluation as well as a lifetime history
of suicide attempts. Of relevance to the current study, all
patients were evaluated on the SADS items assessing psy-
chic anxiety, depressed mood, and irritability. Additional
questions were included to rate the items on the 17-item
Hamilton Depression Rating Scale (HAM-D)30 and the
Hamilton Anxiety Rating Scale (HAM-A).31 Details regard-
ing interviewer training and diagnostic reliability are avail-
able in other publications from the MIDAS project, which
have documented high reliability in diagnosing anxiety
and mood disorders.32 The Rhode Island Hospital institu-
tional review committee approved the research protocol,
and all patients provided informed, written consent.
The DSM-5 Anxious Distress Specifier Interview
(DADSI) assesses the 5 symptoms of the anxious distress
specifier (feeling keyed up or tense, feeling restless, diffi-
culty concentrating because of worry, fear that something
awful might happen, and feeling that one might lose con-
trol). The probes of the DADSI inquire about symptom
presence and severity for the past week, and determine if
the symptom is present for the majority of the depressive
episode. Item severity for the past week is rated from 0 to 4.
Total scale scores range from 0 to 20. The DADSI interview
was integrated into the SCID and completed immediately
after the depression section. The joint-interview inter-rater
reliability of the DADSI was examined in 25 patients.33
The reliability of the total scale dimensional score was
high (item characteristic curve [ICC] = .93), as was the reli-
ability of anxious distress subtyping (kappa = 1.00). The
test-retest inter-rater reliability of the DADSI was exam-
ined in a separate subsample of 25 patients. The test-retest
reliability of the total scale dimensional score was excel-
lent (ICC = 0.80), and the reliability of anxious distress
subtyping was good (kappa = 0.60).
MEASURING ANXIETY IN PATIENTS WITH BIPOLAR DEPRESSION
May 2020 | Vol. 32 No. 2 | Annals of Clinical Psychiatrye4
The patients completed the Clinically Useful
Depression Outcome Scale (CUDOS),34 the Clinically
Useful Anxiety Outcome Scale (CUXOS),35 and the
Clinically Useful Anger Outcome Scale (CUANGOS).36
The self-report scales were usually completed prior to the
diagnostic interview. The ratings on the DADSI were made
blind to the results of the self-report scales.
The CUDOS contains items assessing all of the
DSM-IV inclusion criteria for MDD.34 The respondent
was instructed to rate the 16 symptom items on a 5-point
ordinal scale indicating “how well the item describes
you during the past week, including today” (0 = not at
all true/0 days; 1 = rarely true/1 to 2 days; 2 = sometimes
true/3 to 4 days; 3 = usually true/5 to 6 days; 4 = almost
always true/every day). Compound DSM-IV symptom
criteria referring to >1 construct (eg, problems concen-
trating or making decisions; insomnia or hypersomnia)
were subdivided into their respective components and
a CUDOS item was written for each component. Total
scores range from 0 to 64. In the present study, the
internal consistency of the CUDOS was .70 in patients
with bipolar disorder.
The CUXOS is a general measure of psychic and
somatic anxiety, rather than a disorder-specific scale.
A factor analysis yielded 2 factors—somatic anxiety (14
items), and psychic anxiety (6 items). The respondent was
instructed to rate the 20 CUXOS items on a 5-point ordinal
scale indicating “how well the item describes you during the
past week, including today” (0 = not at all true; 1 = rarely true;
2 = sometimes true; 3 = usually true; 4 = almost always
true). Total scores range from 0 to 80. In the present study,
the internal consistency of the CUXOS was .91.
The 13-item CUANGOS is a general measure of irrita-
bility and aggression. The rating instructions are the same
as the CUXOS. Total scores range from 0 to 52. In the pres-
ent study the internal consistency of the CUANGOS was .93.
Data analyses
We examined convergent and discriminant validity37 by
examining the correlation of the DADSI dimensional
TABLE 1
Demographic characteristics of patients with bipolar depression and major depressive disorder
Bipolar depression
(n = 49)
Major depressive disorder
(n = 369) 2-group test
n % n % χ2 P
Gender
Male 15 30.6 101 27.4 2.0 .57
Female 34 69.4 254 68.8
Transgender 00.0 82.2
Genderqueer/other 00.0 61.6
Education
Less than high school 24.1 22 6.0 1.8 .40
Graduated high school 27 55.1 231 62.6
Graduated college 20 40.8 116 31.4
Marital status
Married 11 22.4 79 21.4 2.0 .85
Living with someone 612.2 45 12.2
Widowed 12.0 92.4
Separated 00.0 13 3.5
Divorced 816.3 50 13.6
Never married 23 46.9 173 46.9
Mean SD Mean SD t P
Age 35.6 13.4 36.5 14.7 0.44 .66
SD: standard deviation.
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score with measures of anxiety (CUXOS psychic and
somatic anxiety, SADS psychic and somatic anxiety,
HAM-A, HAM-D anxiety-somatization factor) and non-
anxious symptoms (CUDOS, CUANGOS, HAM-D, SADS
depressed mood, SADS irritability).
We used t tests to determine whether DADSI scores
were significantly higher in patients with specific anxiety
disorders compared with patients without an anxiety dis-
order. We used Levene’s test for equality of variances to
examine homogeneity of variance of the 2 samples, and
when significant, used separate variance estimates with
adjusted degrees of freedom.
RESULTS
Demographic characteristics
The majority of the patients with bipolar disorder were
white, female high school graduates. Twenty-seven
patients were diagnosed with bipolar I disorder and 22
with bipolar II disorder. There were no differences in the
demographic characteristics of the patients with MDD and
bipolar depression (TABLE 1).
Subtype and item frequency
The majority of the patients with bipolar depression and
MDD met the DSM-5 anxious distress specifier criteria,
and there was no difference between the groups (TABLE 2).
There was no difference in symptom frequency between
the groups, and the rank order of item frequencies was
the same in the 2 groups (TABLE 2). Likewise, there was no
difference in the mean item scores or total score between
the patients with bipolar depression and MDD (TABLE 3).
Discriminant and convergent validity
The data in TABLE 4 show that the DADSI was more
highly correlated with measures of anxiety (mean r = .49)
than with measures of the other symptom domains
(mean r = .29). The DADSI was nonsignificantly more
highly correlated with the HAM-D than with the HAM-A
TABLE 2
Frequency of the DSM-5 anxious distress specifier criteria in patients with bipolar depression and
major depressive disorder
DSM-5 anxious distress specifier criterion, n (%)
Bipolar depression
(n = 49)
Major depressive
disorder (n = 369) χ2P
Feeling keyed up or tense 31 (63.3) 234 (63.4) 0.00 0.98
Feeling unusually restless 23 (46.9) 201 (54.5) 0.99 0.32
Difficulty concentrating because of worry 36 (73.5) 266 (72.1) 0.04 0.84
Feeling that something awful may happen 25 (51.0) 156 (42.3) 1.35 0.25
Feeling that the individual might lose control of himself/herself 20 (40.8) 127 (34.4) 0.78 0.38
Anxious distress subtype 39 (79.6) 282 (76.4) 0.24 0.62
TABLE 3
Dimensional scores of the DSM-5 anxious distress specifier criteria in patients with bipolar
depression and major depressive disorder
DSM-5 anxious distress specifier criterion,
mean (SD)
Bipolar depression
(n = 49)
Major depressive
disorder (n = 369) t P
Feeling keyed up or tense 2.4 (1.4) 2.5 (1.4) 0.57 .57
Feeling unusually restless 1.6 (1.4) 1.8 (1.4) 1.05 .29
Difficulty concentrating because of worry 3.0 (1.4) 2.9 (1.4) −0.72 .47
Feeling that something awful may happen 2.1 (1.5) 1.7 (1.6) −1.65 .10
Feeling that the individual might lose control of himself/
herself
1.7 (1.4) 1.4 (1.5) −1.22 .22
Total score 10.8 (4.3) 10.3 (4.6) −0.71 .48
SD: standard deviation.
MEASURING ANXIETY IN PATIENTS WITH BIPOLAR DEPRESSION
May 2020 | Vol. 32 No. 2 | Annals of Clinical Psychiatrye6
(.56 vs .45, z = .68, P = .50), though this was due to the
inclusion of anxiety items on the HAM-D. After the items
of the HAM-D anxiety-somatization factor were removed,
the correlation between the DADSI and HAM-D dropped
from .56 to .34, and the DADSI was nearly twice as highly
correlated with the HAM-D anxiety-somatization factor
than with the remaining items on the HAM-D (.61 vs .34,
z = 1.70, P = .09). Thus, the DADSI shared more than
3 times as much variance with the HAM-D anxiety/
somatization factor (38%) than it did with the remaining
items on the HAM-D (11%).
The DADSI was 2 times more highly correlated with
the SADS rating of psychic anxiety than somatic anxi-
ety (.56 vs .27, z = 1.71, P = .09). Consistent with this, the
DADSI was more highly correlated with the CUXOS psy-
chic anxiety subscale than with the somatic anxiety sub-
scale (.65 vs .41, z = 1.6, P = .11).
Association with psychiatric diagnosis
Patients with panic disorder scored significantly higher
than patients with no current anxiety disorder on the
DADSI total score (12.2 + 3.3 vs 7.8 + 2.8, t = 2.69, P <
.05). Similarly, patients with generalized anxiety disor-
der (GAD) scored significantly higher than the patients
without an anxiety disorder (12.2 + 3.7 vs 7.8 + 2.8,
t = 2.51, P < .05).
DISCUSSION
The majority of patients with bipolar depression met the
DSM-5 anxious distress specifier, which was no different
than the frequency of anxious distress in patients with
MDD. The DADSI was significantly correlated with other
measures of anxiety and more highly correlated with
other measures of anxiety than with measures of depres-
sion and irritability, and patients with comorbid panic
disorder and GAD achieved higher scores. Thus, the
results of the present study indicate that anxious distress
is common in patients with bipolar depression, and sup-
port the validity of the DSM-5 anxious distress specifier.
The association between the DSM-5 anxious dis-
tress specifier and a diagnosis of GAD and panic dis-
order is not surprising given the overlap in symptom
criteria. Three of the anxious distress specifier criteria
overlap with criteria for GAD (feeling “keyed up” or
tense, feeling restless, difficulty concentrating because
of worry) and one criterion overlaps with a criterion
TABLE 4
Discriminant and convergent validity of the DADSI scores in patients with bipolar depression
Measures Correlation with DADSI, ra
Measures of anxiety symptoms
Hamilton Anxiety Rating Scale 0.45b
Hamilton Depression Rating Scale, anxiety/somatization factor 0.61c
SADS psychic anxiety 0.56c
SADS somatic anxiety 0.27
Clinically Useful Anxiety Outcome Scale psychic anxiety 0.65c
Clinically Useful Anxiety Outcome Scale somatic anxiety 0.41b
Measure of nonanxious symptoms
17-item Hamilton Depression Rating Scale 0.56c
17-item Hamilton Depression Rating Scale (excluding anxiety/somatization factor items) 0.34a
SADS depressed mood 0.11
SADS irritability 0.29a
Clinically Useful Depression Outcome Scale 0.11
Clinically Useful Anger Outcome Scale 0.31a
aP < .05
bP < .01
cP < .001
Three patients did not complete the self-report measures.
DADSI: DSM-5 Anxious Distress Specifier Interview; SADS: Schedule for Affective Disorders and Schizophrenia.
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ANNALS OF CLINICAL PSYCHIATRY
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for panic disorder (feeling that one might lose control).
Studies of the anxious distress specifier in patients with
MDD have likewise found significantly elevated rates of
panic disorder and GAD in patients who met the anx-
ious distress specifier.21,22,26
In accordance with the results of studies of the
anxious distress specifier in patients with MDD, anx-
ious distress was associated with greater severity of
depression, irritability, as well as overall anxiety.22,26,38
The significant association among these 3 mood states
is consistent with the inclusion of irritability as a diag-
nostic criterion for GAD, as well as studies showing
that patients with high levels of anger have increased
rates of anxiety disorders,39 patients with bipolar dis-
order have high rates of anxiety disorders,5,18,40,41 and
patients with anxiety disorders have elevated rates of
bipolar disorder.16,42
The anxious distress specifier was included in
DSM-5 in the absence of prior research on its empirical
validity or clinical utility. DSM-5, like its predecessors,
includes criteria for a number of specific anxiety disor-
ders that can be diagnosed in patients with bipolar disor-
der. A new diagnostic entity, such as the DSM-5 anxious
distress specifier, should demonstrate an improvement
in either validity or clinical utility over and above what is
already established in the DSM.
Limitations
A limitation of the present study is that we were unable
to examine incremental validity because too few patients
did not meet the criteria for the specifier.
Another limitation is that the present study was
conducted in a single clinical practice in which most
patients were white, female, and had health insurance.
Replication in samples with different demographic char-
acteristics is warranted. It will also be important to repli-
cate these findings in an outpatient sample.
CONCLUSIONS
The results of our study indicate that anxious distress is
common in patients with bipolar depression and support
the validity of the DSM-5 anxious distress specifier. ■
DISCLOSURES: The authors report no financial relationships
with any companies whose products are mentioned in this
article, or with manufacturers of competing products.
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