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Psychopharmacology

, Volume 235, Issue 12, pp 3451–3464 | Cite as

Cognitive and socio-cognitive functioning of chronic non-medical prescription opioid users

  • Sara L. Kroll
  • Emilija Nikolic
  • Franziska Bieri
  • Michael Soyka
  • Markus R. Baumgartner
  • Boris B. Quednow
Original Investigation

Abstract

Rationale

Non-medical prescription opioid use (NMPOU) has become a major public health issue in the USA and is also increasing in Europe. However, little is known about neuropsychological associations of NMPOU—specifically regarding social cognition, which is essential for social functioning and treatability of opioid dependence. Previous studies with heroin users and opioid-substituted patients reported deficits in various cognitive functions, but these results are likely confounded by comorbid physical and psychiatric diseases, overdose-associated hypoxia, and adulteration of street heroin. Therefore, the purpose of the present study was to investigate social and non-social cognition in a relatively pure NMPOU sample taking opioid analgesics or antitussives.

Methods

We assessed 23 individuals with NMPOU objectively confirmed by hair analyses and 29 opioid-naïve, healthy controls, employing a comprehensive neuropsychological test battery.

Results

Significant impairments were found between NMPOU individuals and controls regarding the cognitive domains of attention (p < .01, Hedge’s g = .85), declarative memory (p < .05, g = .66), and global cognitive empathy (p < .01, g = 0.99)—the latter included problems with emotion recognition from faces, voices, and complex scenes. Opioid hair concentrations transformed to morphine equivalents were negatively correlated with global cognitive empathy (r = − 0.52, p < .01), suggesting dose-dependent deficits.

Conclusion

In contrast to stimulant users primarily displaying deficits in emotional empathy, opioid users showed relatively selective impairments in measures of cognitive empathy, with dose-dependent effects suggesting potential opioid-induced deficits and involvement of the opioid-system in processes of cognitive empathy. These results have important implications for future interventions of opioid dependence targeting social functioning and consequently enhancing therapy outcome and preventing relapse.

Keywords

Cognition Emotion recognition Empathy Morphine Codeine Prescription opioid Opioid addiction 

Notes

Acknowledgments

We are grateful to Matthias Humm (Drug Information Centre, DIZ, and www.saferparty.ch), Markus Herdener (University Hospital for Psychiatry Zurich and Centre for Use Disorders, ZAE), and Andreas Wahl-Kordon (Oberbergklinik Schwarzwald) for supporting the recruitment. Furthermore, we thank Jael Bernath, Martina Thoma, and Kateryna Mudrak for their excellent support with the assessment of the participants. We are also grateful to Dr. David Cole for the proof-reading of our manuscript.

Authors’ contribution

SLK and BBQ designed the study. MS supported the recruitment and the implementation of the study. SLK, EN, and FB conducted the assessments. MRB conducted the hair analyses. SLK conducted the statistical analyses. SLK and BBQ wrote the first draft of the manuscript. All authors contributed to and have approved the final manuscript.

Funding

The study was funded by the Herzog-Egli Foundation and starting grants of the Medical Faculty of the University of Zurich and of the Psychiatric Hospital of the University of Zurich to BBQ. SLK was financed by a grant of the Swiss National Science Foundation (105319_162639/1) to BBQ.

Compliance with ethical standards

The study was approved by the Cantonal Ethics Committee of Zurich. All participants provided written informed consent and received compensation for their participation.

Conflict of interest

The authors declare that there is no conflict of interest.

Supplementary material

213_2018_5060_MOESM1_ESM.docx (87 kb)
ESM 1 (DOCX 87.2 kb)

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy, and PsychosomaticsPsychiatric Hospital of the University of ZurichZurichSwitzerland
  2. 2.Psychiatric Hospital of the University of MunichMunichGermany
  3. 3.Medical Park ChiemseeblickBernau am ChiemseeGermany
  4. 4.Center for Forensic Hair Analysis, Institute of Forensic MedicineUniversity of ZurichZurichSwitzerland
  5. 5.Neuroscience Center ZurichUniversity of Zurich and Swiss Federal Institute of Technology ZurichZurichSwitzerland

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