Neuropsychological performance in patients with substance use disorder with and without mood disorders

Abstract

Background: Mood disorders commonly co-occur in patients with substance use disorders (SUD). This combination may increase the risk of pathological effects and impair cognitive functioning.

Aim: The aim of the study was to examine the effects of mood and substance use disorders on specific neuropsychological measures.

Methods: The participants comprised 164 hospitalised patients, 88 with (SUD + MD) and 76 (SUD–MD) without mood disorders, ranging in age from 19 to 65 years. Their diagnostic assessment was based on a psychiatric interview (ICD-10). Neuropsychological tests were carried out after a minimum of one month of abstinence.

Results: Processing speed (p = 0.029), and perceptual reasoning (p = 0.039) were more impaired in the SUD + MD group than in the SUD–MD group. An Analysis of covariance (ANCOVA) controlled for age, education level, learning difficulties and polysubstance use revealed that the groups were most powerfully separated by the Digit Symbol test and the Block Design test.

Conclusions: Patients with substance abuse and mood disorders seem to have more deficits in speed processing and perceptual reasoning than substance abuse patients without mood disorders. These processing speed difficulties and perceptual problems may impact prognosis and treatment. The Digit Symbol test and the Block Design test are a fast and sensitive ways to examine treatment effectiveness and monitor treatment progress.

Keywords:

• Substance abuse
• mood disorders
• inpatients
• neuropsychological functions
• diagnostic differentiation

Ethical approval

All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Irma Höijer

Irma Höijer (M.Sc.) is neuropsychologist with a trauma psychotherapy training. She is working as a private psychotherapist.

Tuula Ilonen

Tuula Ilonen, PhD, adjunct professor in clinical psychology at the University of Turku is working as a senior lecturer and researcher in the Department of Psychiatry.

Eliisa Löyttyniemi

Eliisa Löyttyniemi (M.Sc. (Mathematics)), is biostatistician, who have worked for several pharmaceutical companies in 1993–2010, continued then developing neonatal and newborn screening technologies. Starting from 2013 she has worked for University of Turku where she is responsible for analysing the research data and teaching medical students.

Raimo K. R. Salokangas

Raimo K. R. Salokangas is a Finnish psychiatrist and professor emeritus. He has been a professor of psychiatry at the University of Turku and a senior physician at the Department of Psychiatry at the University of Turku.