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 RESEARCH ARTICLE

Is the distinction between adjustment disorder with depressed mood and adjustment disorder with mixed anxious and depressed mood valid?

Mark Zimmerman, MD

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA

Jennifer H. Martinez, BA

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA

Kristy Dalrymple, PhD

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA

Iwona Chelminski, PhD

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA

Diane Young, PhD

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA

BACKGROUND: In the DSM-IV, adjustment disorder is subtyped according to the predominant presenting feature. The different diagnostic code numbers assigned to each subtype suggest their significance in DSM-IV. However, little research has examined the validity of these subtypes. In the present report from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, we compared the demographic and clinical profiles of patients diagnosed with adjustment disorder subtypes to determine whether there was enough empirical evidence supporting the retention of multiple adjustment disorder subtypes in future versions of the DSM.

METHODS: A total of 3,400 psychiatric patients presenting to the Rhode Island Hospital outpatient practice were evaluated with semistructured diagnostic interviews for DSM-IV Axis I and Axis II disorders and measures of psychosocial morbidity.

RESULTS: Approximately 7% (224 of 3,400) of patients were diagnosed with current adjustment disorder. Adjustment disorder with depressed mood and with mixed anxious and depressed mood were the most common subtypes, accounting for 80% of the patients diagnosed with adjustment disorder. There was no significant difference between these 2 groups with regard to demographic variables, current comorbid Axis I or Axis II disorders, lifetime history of major depressive disorder or anxiety disorders, psychosocial morbidity, or family history of psychiatric disorders. The only difference between the groups was lifetime history of drug use, which was significantly higher in the patients diagnosed with adjustment disorder with depressed mood.

CONCLUSIONS: There is no evidence supporting the retention of both of these adjustment disorder subtypes, and DSM-IV previously set a precedent for eliminating adjustment disorder subtypes in the absence of any data. Therefore, in the spirit of nosologic parsimony, consideration should be given to collapsing the 2 disorders into 1: adjustment disorder with depressed mood.

KEYWORDS: adjustment disorder, diagnostic validity, subtypes

ANNALS OF CLINICAL PSYCHIATRY 2013;25(4):257-265

  Introduction

As part of the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, we recently examined the validity of differentiating types of subthreshold depression.1 Specifically, we compared patients diagnosed with adjustment disorder with depressed mood and depressive disorder not otherwise specified (DDNOS). We did not include patients diagnosed with adjustment disorder with depressed and anxious mood in the adjustment disorder group because we were unsure how this might impact the comparison with the DDNOS group.

In DSM-IV, adjustment disorder is subtyped according to the predominant presenting feature. The 6 subtypes are adjustment disorder with depressed mood, anxious mood, mixed depressed and anxious mood, disturbance of conduct, disturbance of conduct and emotions, and unspecified. The significance of each subtype in DSM-IV is suggested by the different diagnostic code numbers assigned to them. However, the text of DSM-IV does not refer to any research suggesting that there is validity in distinguishing between the subtypes. Likewise, recent reviews of the adjustment disorder category have not cited evidence of the validity of the distinction between adjustment disorder subtypes.2,3

We are aware of only 1 study comparing adjustment disorder subtypes: Despland, Monod, and Ferrero4 compared 4 groups of psychiatric outpatients diagnosed with adjustment disorder with depressed mood, anxiety, depressed and anxious mood, and other. Patients with anxiety were younger and more frequently male than the patients with depressed mood and depressed and anxious mood. There were few differences between the groups on demographic variables, frequency of a comorbid Axis I or Axis II diagnosis, Axis III comorbidity, and length of psychiatric treatment. There were no significant differences between the depressed mood and depressed and anxious mood groups. However, a limitation of the study was that diagnoses were based on unstandardized clinical evaluations, and a limited number of clinical variables were examined.

In the present report from the MIDAS project, we compared the demographic and clinical profiles of patients diagnosed with adjustment disorder subtypes to determine whether there was enough empirical evidence supporting the retention of multiple adjustment disorder subtypes in future versions of the DSM. Analogous to the differences between patients with major depressive disorder (MDD) with and without comorbid anxiety, we hypothesized that the patients with adjustment disorder with depression and anxiety would have greater psychosocial morbidity than the patients with adjustment disorder with depressed mood. We also predicted that the depressed and anxious mood group would have a greater lifetime rate of anxiety disorders and family history of anxiety disorders.

  Methods

The MIDAS project represents an integration of research methodology into a community-based outpatient practice affiliated with an academic medical center.5-7 A comprehensive diagnostic evaluation is conducted on presentation for treatment. This private practice group predominantly treats individuals with medical insurance (excluding Medicaid) on a fee-for-service basis and is distinct from the hospital’s outpatient residency training clinic, which primarily serves lower income, uninsured, and medical assistance patients. Data on referral source was recorded for the last 1,600 patients enrolled in the study. Patients were most frequently referred from primary care physicians (29.9%), psychotherapists (16.1%), and family members or friends (18.8%). The Rhode Island Hospital institutional review committee approved the research protocol, and all patients provided informed, written consent.

The sample examined in the present report is derived from the 3,400 psychiatric outpatients evaluated with semistructured diagnostic interviews. The patients were interviewed by a diagnostic rater who administered a modified version of the Structured Clinical Interview for DSM-IV (SCID) for Axis I disorders.8 During the course of the MIDAS project, the assessment battery has been subject to change. The assessment of all DSM-IV personality disorders was not introduced until the study was well under way and the procedural details of incorporating research interviews into our clinical practice had been well established. Only 2,150 of the 3,400 patients were administered the full Structured Interview for DSM-IV Personality (SIDP-IV).9

Our interest in the psychometric performance of the DSM-IV symptom criteria for major depression led to our modification of the SCID and elimination of the skip-out that curtails the depression module for patients who did not report either depressed mood or loss of interest or pleasure. We inquired about all of the patients’ depression symptoms; for compound criteria that encompassed ≥1 symptom (eg, indecisiveness or impaired concentration, increased sleep or insomnia), we made separate ratings of each component of the diagnostic criterion. The 9 DSM-IV symptom criteria were broken down into 17 parts. All patients were rated on the Clinical Global Index (CGI) of depression severity.10 The SCID was supplemented with questions from the Schedule for Affective Disorders and Schizophrenia (SADS)11 on the patients’ best level of social functioning and the amount of time they spent unemployed during the past 5 years. The interview also ascertained lifetime history of psychiatric hospitalizations and suicide attempts.

Family history diagnoses were based on information provided by the patient. The interview followed the guide provided in the Family History Research Diagnostic Criteria (FH-RDC),12 and assessed the presence or absence of problems with anxiety, mood, substance use, and other psychiatric disorders for all first-degree family members. Morbid risks were calculated using age-corrected denominators or Bezugsziffers, based on Weinberg’s shorter method.13 Relatives over the age of risk for the particular illness were given a value of 1, those within the age gap for risk were given a value of 0.5, and those below it were given a value of 0. These ages of risk were based on the distribution of ages of onset in our probands.14 Morbid risks were compared using the chi-square statistic.

The diagnostic raters were highly trained and monitored throughout the project to minimize rater drift. The training of the diagnostic raters has been described in other reports from the MIDAS project.5 Throughout the MIDAS project, ongoing supervision of the raters consisted of weekly diagnostic case conferences involving all members of the team. Written reports of all cases were reviewed by the principal investigator (M.Z.), who also reviewed the item ratings of every case.

Statistical analysis

We compared the demographic, family history, and clinical characteristics of patients with adjustment disorder subtypes. To compare the groups on continuously distributed variables, t tests were used. Categorical variables were compared using the chi-square statistic, or by using the Fisher exact test if the expected value in any cell of a 2 × 2 table was <5.

  Results

Approximately 7% (224 of 3,400) of the patients were diagnosed with current adjustment disorder. The data in TABLE 1 show that adjustment disorder with depressed mood and with mixed anxious and depressed mood were the most common subtypes, accounting for 80% of the patients diagnosed with adjustment disorder. The majority of patients diagnosed with adjustment disorder received it as their principal diagnosis (86.6%, 194 of 224). There was no significant difference between subtypes in the likelihood of being diagnosed as the principal diagnosis (TABLE 1). Patients with a principal diagnosis of another disorder with comorbid adjustment disorder are clinically different from patients with a principal diagnosis of adjustment disorder; therefore we limited our comparisons of the adjustment disorder subtypes to patients given the diagnosis of adjustment disorder as their principal diagnosis. We only compared patients diagnosed with the depressed mood and mixed anxious and depressed mood subtypes because the sample sizes were too small for the other subtypes.


TABLE 1

Frequency of adjustment disorder subtypes

Subtype Current diagnosis Principal diagnosis Additional diagnosis
n %a n %b n %b
Depressed mood 89 39.7% 76 85.4% 13 14.6%
Anxious mood 34 15.2% 28 82.4% 6 17.6%
Mixed depressed and anxious mood 92 41.1% 82 89.1% 10 10.9%
Disturbance of conduct 1 0.4% 1 100.0% 0 0.0%
Disturbance of emotions and conduct 1 0.4% 1 100.0% 0 0.0%
Unspecified 7 3.1% 6 85.7% 1 14.3%
aPercentage of patients with adjustment disorder (n=224) with the specific subtype.
bPercentage of patients with that particular subtype who received the diagnosis as the principal or additional diagnosis. Thus, for each adjustment disorder subtype, the percentages add to 100%.

The data in TABLE 2 show that the majority of the patients were white, female high school graduates. There were no significant demographic differences between the 2 groups.


TABLE 2

Demographic characteristics of psychiatric outpatients with adjustment disorder with depressed mood (n=76) and adjustment disorder with depressed and anxious mood (n=82)

Characteristic Depressed mood Mixed depressed and anxious mood χ2 P
n % n %
Sex
  Male 34 44.7% 35 42.7% 0.07 ns
  Female 42 55.3% 47 57.3%  
Education
  Less than high school 4 5.3% 5 6.1%   ns
  Graduated high school 43 56.6% 48 58.5% 0.16
  Graduated college or greater 29 38.2% 29 35.4%  
Marital status
  Married 35 46.1% 46 56.1%   ns
  Living with someone 5 6.6% 6 7.3%  
  Widowed 0 0.0% 4 4.9% 9.16
  Separated 2 2.6% 4 4.9%  
  Divorced 12 15.8% 10 12.2%  
  Single 22 28.9% 12 14.6%  
Race
  White 72 94.7% 76 92.7%   ns
  Black 3 3.9% 4 4.9% 3.03
  Hispanic 0 0.0% 1 1.2%  
  Other 1 1.3% 1 1.2%  
Age (years), mean (SD) 41.4 14.4 44.5 14.8 –1.3 ns
SD: standard deviation.

Approximately one-third of the patients had another current psychiatric disorder, and more than one-half had a lifetime history of another Axis I disorder (TABLE 3 and TABLE 4). The most frequent current disorders were anxiety disorders, whereas the most common lifetime disorder was a substance use disorder. The only difference between the groups was a lifetime history of drug use disorder, which was significantly higher in the patients diagnosed with adjustment disorder with depressed mood. Of note, there was no significant difference in lifetime history of MDD or any specific anxiety disorder.


TABLE 3

Frequency of current DSM-IV diagnoses in psychiatric outpatients with adjustment disorder with depressed mood (n=76) and adjustment disorder with depressed and anxious mood (n=82)

Axis I diagnosis Depressed mood Mixed depressed and anxious mood χ2 P
n % n %
Anxiety disorder
  Panic disorder 2 2.6% 3 3.7% 0.27 ns
  Social phobia 7 9.2% 8 9.8% 0.01 ns
  Specific phobia 3 3.9% 1 1.2% Fisher ns
  Posttraumatic stress disorder 1 1.3% 3 3.7% Fisher ns
  Generalized anxiety disorder 4 5.3% 5 6.1% Fisher ns
  Obsessive-compulsive disorder 2 2.6% 0 0.0% Fisher ns
  Any anxiety disorder 16 21.1% 15 18.3% 0.19 ns
Substance use disorder
  Alcohol abuse/dependence 7 9.2% 9 11.0% 0.14 ns
  Drug abuse/dependence 4 5.3% 2 2.4% Fisher ns
  Any substance use disorder 11 14.5% 9 11.0% 0.44 ns
Any eating disorder 2 2.6% 3 3.7% Fisher ns
Any psychotic disorder 0 0.0% 0 0.0%
Any somatoform disorder 0 0.0% 2 2.4% Fisher ns
Any impulse control disorder 0 0.0% 3 3.7% Fisher ns
Any additional Axis I disorder 26 34.2% 26 31.7% 0.11 ns
≥2 additional Axis I diagnoses 7 9.2% 10 12.2% 0.37 ns

TABLE 4

Frequency of lifetime DSM-IV diagnoses in psychiatric outpatients with adjustment disorder with depressed mood (n=76) and adjustment disorder with depressed and anxious mood (n=82)

Axis I diagnosis Depressed mood Mixed depressed and anxious mood χ2 P
n % n %
Mood disorder
  Major depressive disorder 22 28.9% 14 17.1% 3.16 ns
  Dysthymic disorder 1 1.3% 0 0.0% 1.09 ns
Anxiety disorder
  Panic disorder 5 6.6% 7 8.5% 1.22 ns
  Social phobia 10 13.2% 9 11.0% 0.18 ns
  Specific phobia 3 3.9% 3 3.7% 0.01 ns
  Posttraumatic stress disorder 4 5.3% 6 7.3% 0.28 ns
  Generalized anxiety disorder 4 5.3% 5 6.1% 0.05 ns
  Obsessive-compulsive disorder 2 2.6% 0 0.0% 2.19 ns
  Any anxiety disorder 24 31.6% 22 26.8% 0.43 ns
Substance use disorder
  Alcohol abuse/dependence 21 27.6% 23 28.0% 0.01 ns
  Drug abuse/dependence 16 21.1% 8 9.8% 3.91 .05
  Any substance use disorder 29 38.2% 26 31.7% 0.72 ns
Any eating disorder 6 7.9% 5 6.1% 0.20 ns
Any psychotic disorder 0 0.0% 0 0.0%
Any somatoform disorder 0 0.0% 2 2.4% Fisher ns
Any impulse control disorder 5 6.6% 3 3.7% Fisher ns
Any additional Axis I disorder 49 64.5% 45 54.9% 1.51 ns
≥2 additional Axis I diagnoses 26 34.2% 23 28.0% 0.70 ns

Relatively few patients diagnosed with adjustment disorder with depressed mood and mixed anxious and depressed mood were diagnosed with a personality disorder (5.3% vs 3.7%; Fisher exact test, ns). Not enough patients were diagnosed with individual disorders to compare the groups on each of the 10 DSM-IV personality disorders, therefore we examined personality disorder dimensional scores. There were no significant differences between the groups on any of the DSM-IV personality disorder dimensional scores (TABLE 5).


TABLE 5

DSM-IV Axis II personality disorder dimensional scores in psychiatric outpatients with adjustment disorder with depressed mood (n=56) and adjustment disorder with depressed and anxious mood (n=51)

Personality disorder, mean (SD) Depressed mood Mixed depressed and anxious mood t P
Paranoid 0.2 (0.5) 0.2 (0.7) 0.31 ns
Schizoid 0.2 (0.6) 0.2 (0.6) 0.66 ns
Schizotypal 0.1 (0.4) 0.1 (0.4) 0.57 ns
Antisocial 0.1 (0.4) 0.2 (0.5) –0.12 ns
Borderline 0.7 (1.0) 0.5 (0.9) 1.03 ns
Histrionic 0.4 (0.9) 0.5 (1.0) –0.28 ns
Narcissistic 0.3 (0.5) 0.4 (0.8) –0.97 ns
Avoidant 0.4 (1.0) 0.4 (0.9) 0.41 ns
Dependent 0.4 (0.8) 0.3 (0.6) 0.93 ns
Obsessive-compulsive 0.6 (0.7) 0.7 (0.9) –0.23 ns

On average, the patients were rated as mildly depressed (mean CGI=1.7). Approximately 10% reported a lifetime history of psychiatric hospitalization (11.4%) or having made a suicide attempt (8.2%). One-quarter (25.0%) missed time from work in the past month because of psychiatric symptoms. The patients with mixed anxiety and depression were rated significantly higher on the SADS psychic anxiety item (2.2±1.3 vs 1.3±1.3; t=–4.6, P < .001) and somatic anxiety item (1.7±1.3 vs 0.8±1.2; t=–4.1, P < .001). There were no significant differences between the groups in terms of severity of depression, ratings on the Global Assessment of Functioning (GAF), severity of suicidal ideation at the time of the evaluation, current social functioning, or days unemployed due to psychiatric illness in the last 5 years (TABLE 6). The groups also did not differ in lifetime history of suicide attempts or psychiatric hospitalizations (TABLE 6), and the morbid risks for depression and anxiety disorders in first-degree relatives were no different between the groups (TABLE 7).


TABLE 6

Psychosocial morbidity in psychiatric outpatients with adjustment disorder with depressed mood (n=76) and adjustment disorder with depressed and anxious mood (n=82)

Morbidity indicator, mean (SD) Depressed mood Mixed depressed and anxious mood t P
Global Assessment of Functioning 60.0 (8.6) 59.4 (7.4) 0.5 ns
Clinical Global Impression Severity 1.8 (0.7) 1.7 (0.8) 0.2 ns
No. of psychiatric hospitalizations 0.2 (0.5) 0.1 (0.3) 1.8 ns
No. of suicide attempts 0.2 (0.6) 0.1 (0.2) 1.7 ns
Suicidal ideation 0.6 (1.0) 0.4 (0.9) 1.3 ns
Current social functioning (past 5 years)a 2.6 (1.1) 2.6 (0.8) 0.4 ns
Adolescent social functioning (12 to 18 years)a 2.4 (1.0) 2.7 (0.9) –1.6 ns
Time unemployed in past 5 yearsa,b 1.6 (1.5) 1.4 (0.6) 1.2 ns
No. of days unemployed past month 2.0 (5.7) 1.7 (4.6) 0.3 ns
aRatings from Schedule of Affective Disorders and Schizophrenia.
bPatients who were not expected to work (eg, student, retired) were excluded, leaving a final sample of 65 with adjustment disorder with depressed mood and 70 with adjustment disorder with depressed and anxious mood.

TABLE 7

Morbid risks for psychiatric disorders in first-degree relatives of psychiatric outpatients with adjustment disorder with depressed mood (n=76) and adjustment disorder with depressed and anxious mood (n=82)

Psychiatric disorder Depressed mooda Mixed depressed and anxious moodb χ2 P
Relatives at risk Morbid risk (%) Relatives at risk Morbid risk (%)
Generalized anxiety disorder 312.5 0.6 358.5 2.0 2.17 ns
Major depression 265 14.3 308 14.0 0.02 ns
Bipolar disorder 268.5 3.4 321.5 1.2 3.02 ns
Panic disorder 273 1.5 312.5 2.9 1.34 ns
Social phobia 360.5 0.8 415 0.0 2.31 ns
Posttraumatic stress disorder 307 0.7 350 1.7 1.54 ns
Obsessive-compulsive disorder 307.5 0.3 349.5 1.1 1.45 ns
Specific phobia 330 0.3 373.5 0.3 7.70 ns
Alcohol abuse/dependence 311 9.6 345 11.6 0.65 ns
Drug abuse/dependence 309 5.5 344.5 4.6 0.25 ns
a75 probands.
b80 probands.

  Discussion

The results of the present study do not support the distinction between adjustment disorder with depressed mood and mixed depressed and anxious mood. There was no significant difference between these 2 groups with regard to demographic variables, current comorbid Axis I or Axis II disorders, lifetime history of MDD or anxiety disorders, psychosocial morbidity, or family history of psychiatric disorders. The only difference between the groups was a lifetime history of drug use, which was significantly higher in the patients diagnosed with adjustment disorder with depressed mood. The present results are therefore consistent with the findings of Despland et al,4 who also found no significant differences between the groups. A limitation of both of these studies, however, is the lack of data on treatment response and longitudinal course.

Some methods of subtyping in DSM-IV are associated with unique diagnostic code numbers (eg, the distinction between psychotic and nonpsychotic MDD, recurrent and single-episode MDD) whereas others are not (eg, major depression with melancholic or atypical features, obsessive-compulsive disorder with or without insight). Whether intended or not, achieving unique diagnostic code status carries with it a level of gravitas suggesting validity. Therefore, when 2 studies fail to validate a distinction that is codified in DSM-IV, it raises the question of whether the distinction between these 2 subtypes should be eliminated.

At least 4 factors should be considered in the decision to delete or retain a subtype in the DSM: the methodological strengths and weaknesses of the negative studies, the data supporting the retention of the subtypes, the presumptive validity or clinical utility of the subtypes, and the tradition in descriptive psychiatry of the subtypes. This study and the one by Despland et al were both conducted with psychiatric outpatient samples. The present study used semistructured diagnostic assessments, whereas the study by Despland et al used unstandardized clinical interviews. The sample sizes were not large, but there were >70 patients in each group in both studies, and as a result, type II error is unlikely to be responsible for the failure to find significant and meaningful group differences. Neither study examined treatment response or longitudinal course, and neither reported on the reliability of distinguishing between the adjustment disorder subtypes. As part of the MIDAS project we have established the reliability of our diagnostic procedures, but the number of patients with adjustment disorder included in the reliability study was too small. It therefore cannot be ruled out that the failure to validate the distinction between adjustment disorders with depressed mood and mixed anxious and depressed mood was due to the poor reliability in making this diagnostic distinction.

  Conclusions

The failure of 2 studies to validate the distinction between these 2 adjustment disorder subtypes is in contrast to the absence of any study that has supported the validity of the distinction. The texts of DSM-III, DSM-III-R, and DSM-IV do not describe any information in support of distinguishing adjustment disorder with depressed mood and adjustment disorder with depressed and anxious mood, and do not describe differential treatment or prognostic implications.

It would be difficult to argue for the retention of both adjustment disorder subtypes on the basis of tradition in descriptive psychiatry. In fact, it should be noted that DSM-III and DSM-III-R originally included 8 adjustment disorder subtypes. Two of these subtypes (adjustment disorder with work or academic inhibition, and adjustment disorder with withdrawal) were eliminated from DSM-IV without explanation or justification. The elimination of disorders should be consistent with an overall goal of achieving a classification system that is as simple as possible, and avoids making distinctions that lack empirical support. Thus, while we do not believe that the results of our study and the study by Despland et al4 are sufficient to merit a change in the nosology, there is no compelling argument to retain both subtypes, and DSM-IV already set a precedent of eliminating adjustment disorder subtypes in the absence of any empirical data. Therefore, in the spirit of nosologic parsimony, we believe consideration should be given to collapsing the 2 disorders into 1: adjustment disorder with depressed mood.

The present report narrowly addressed the distinction between adjustment disorders with depressed mood vs adjustment disorders with anxious and depressed mood. To be sure, there are a number of controversies regarding the nosologic status of adjustment disorders,15-17 and the DSM-5 Work Group for Trauma- and Stressor-Related Disorders has proposed the addition of 2 more subtypes.18 Future research should continue to examine the validity of the different subtypes of adjustment disorders.

DISCLOSURE: The authors report no financial relationships with any company whose products are mentioned in this article or with manufacturers of competing products.

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CORRESPONDENCE: Mark Zimmerman, MD 146 West River Street Providence, RI 02905 USA E-MAIL: mzimmerman@lifespan.org