Differential Diagnosis: Diagnostic Process
Diagnoses of psychiatric disorders should be provisional and constantly reevaluated. In addiction treatment populations, many psychiatric disorders are substance-induced disorders that are caused by AOD use. Treatment of the AOD disorder and an abstinent period of weeks or months may be required for a definitive diagnosis of an independent psychiatric disorder. Unfortunately, the severely depressed person may drop out of treatment or even commit suicide while the clinician is trying to sort things out (see section on “Assessing Danger to Self or Others.”)
Acute manic symptoms may be induced or mimicked by intoxication with stimulants, steroids, hallucinogens, or polydrug combinations. They may also be caused by withdrawal from depressants such as alcohol and by medical disorders such as AIDS and thyroid problems. Acute mania with its hyperactivity, psychosis, and often aggressive and impulsive behavior is an emergency and should be referred to emergency mental health professionals. This is true whatever the causes may appear to be.
Other psychiatric conditions can mimic mood disorders. The predominant condition that mimics a mood disorder is addiction, which is frequently undiagnosed or misdiagnosed. Disorders that can complicate diagnosis include schizophrenia, brief reactive psychosis, and anxiety disorders.
Patients with personality disorders, especially of the borderline, narcissistic, and antisocial types, frequently manifest symptoms of mood disorders. These symptoms are often fluid and may not meet the diagnostic criterion of persistence over time. In addition, all of the psychiatric disorders noted here can coexist with AOD and mood disorders.
Case Examples: George and Mary
George is a 37-year-old divorced male who was brought into the emergency room intoxicated. His blood alcohol level was 152, and the toxicology screen was positive for cocaine. He was also suicidal (“I’m going to do it right this time! I’ve got a gun.”). He has a history of three psychiatric hospitalizations and two inpatient AOD treatments. Each psychiatric admission was preceded by AOD use. George has never followed through with psychiatric treatment. He has intermittently attended AA, but not recently.
Mary is a 37-year-old divorced female who was brought into a detoxification unit with a blood alcohol level of 150 and was noted to be depressed and withdrawn. She has never used drugs (other than alcohol), and began drinking alcohol only 3 years ago. However, she has had several alcohol-related problems since then. She has a history of three psychiatric hospitalizations for depression, at ages 19, 23, and 32. She reports a positive response to antidepressants. She is currently not receiving AOD or psychiatric treatment.
Differential diagnostic issues for case examples.
Many factors must be examined when making initial diagnostic and treatment decisions. For example, what if George’s psychiatric admissions were 2 or 3 days long — usually with discharges related to leaving against medical advice? Decisions about diagnosis and treatment would be quite different if two of his psychiatric admissions were 4 to 6 weeks long with clearly defined manic and psychotic symptoms continuing throughout the course, despite aggressive use of psychiatric treatment and medication.
Similarly, what if Mary had abstained from alcohol for 6 months “on her own,” but over the past 3 months, she had become increasingly depressed, tired, and withdrawn, with disordered sleep and poor concentration, as well as suicidal thoughts? In addition, last night, while planning to kill herself, she relapsed. A different diagnostic picture would emerge in this case if Mary had been using antidepressants for the past year and, during the past month, she had experienced an increase in heavy drinking, losing her job yesterday because of alcohol use.
Ries, R. (2007). Mood Disorders and Alcohol/Drug Use. Psych Central. Retrieved on November 27, 2014, from http://psychcentral.com/lib/mood-disorders-and-alcoholdrug-use/0001151
Last reviewed: By John M. Grohol, Psy.D. on 30 Jan 2013
Published on PsychCentral.com. All rights reserved.