Boris Quednow

Prof. Dr.

Pharmacopsychologist , Psychiatric University Hospital Zurich

Zurich, Switzerland


Boris B. Quednow studied psychology at the University of Bonn. He wrote his dissertation on the neurobiological consequences of Ecstasy (MDMA) use at the Ruhr-University of Bochum and worked as a research assistant at the Department of Psychiatry of the University of Bonn. At present, he is Associate Professor for Experimental and Clinical Pharmacopsychology at the Department for Psychiatry, Psychotherapy, and Psychosomatics of the Psychiatric University Hospital Zurich. His main research interests are the behavioral neurotoxicology and neuroplasticity of substance use as well as the neuropsychopharmacology of disturbed brain functions in psychiatric disorders, particularly in schizophrenia and addiction.

Polysubstance Use in Early Adulthood: Patterns and Developmental Precursors in an Urban Cohort

Polysubstance use increases the risk of severe health problems and social impairments. The present study leverages community-representative, long-term longitudinal data from an urban cohort from the area of Zurich to assess a) the prevalence and continuation of polysubstance use between adolescence and early adulthood, b) different patterns of polysubstance use in early adulthood, and c) childhood risk factors for polysubstance use in early adulthood. The results show that polysubstance use increased between early adolescence and early adulthood. The continuation of polysubstance use was common. At age 20, more than one-third of participants reported polysubstance use (involving illicit substances and nonmedical use of prescription drugs). Four latent classes with polysubstance use were identified: 1) broad spectrum of substances, 2) cannabis and club drugs, 3) cannabis and the nonmedical use of prescription drugs, and 4) different cannabinoids. Risk factors for any polysubstance use included childhood sensation-seeking and exposure to others’ substance use; some childhood risk factors were differentially associated with the four classes (e.g., low self-control in childhood was associated with an increased likelihood of being in the broad spectrum class). The classes also differed with regard to socio-demographic factors. In conclusion, this study revealed that polysubstance use is a widespread and multifaceted phenomenon that typically emerges during adolescence.

Lecture & Discussion
14.00 - 15.30


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