Digital Public Defence: Socheat Cheng

MD, Mphil Socheat Cheng at Institute of Clinical Medicine will be defending the thesis "Medication misuse and dependence among hospitalized older patients: Cross-sectional studies focusing on prescribed central nervous system depressants" for the degree of PhD (Philosophiae Doctor).

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The public defence will be held as a video conference over Zoom.

The defence will follow regular procedure as far as possible, hence it will be open to the public and the audience can ask ex auditorio questions when invited to do so.

Click here to participate in the digital public defence 

Download Zoom here


Digital Trial Lecture – time and place

See Digital Trial Lecture.

Adjudication committee

  • First opponent: Clinical Pharmacist Lorenz Van der Linden, University Hospital Leuven
  • Second opponent: Professor Anette Hylen Ranhoff, University of Bergen
  • Third member and chair of the evaluation committee: Professor II Anners Lerdal, University of Oslo

Chair of the Defence

Professor II Ole Morten Rønning, University of Oslo

Principal Supervisor

Professor II Christofer Lundqvist, University of Oslo


Timely recognition of medication misuse and dependence in older patients is crucial to prevent adverse drug events. However, this task has been challenging due to the lack of age-specific screening tools. Moreover, evidence on which patients are at risk, and their characteristics, is limited.

We conducted cross-sectional studies among older patients, admitted to somatic wards of the Akershus University Hospital, with focus on three types of central nervous system depressant drugs (CNSDs): opioid analgesics, benzodiazepines and Z-hypnotics.

One of our aims was to assess usability of the Severity of Dependence Scale (SDS) in older patients. We found that that the SDS was reliable, valid, and detected medication misuse and dependence among hospitalized older patients with good diagnostic performance.

Our study also revealed a high proportion of patients using CNSDs against recommended guidelines. Three factors were found to be associated with higher odds of prolonged use of these medications: being aged ≥ 75 years, intense pain, and concurrent use of many medications (polypharmacy). Furthermore, we found that older patients with prolonged CNSD use reported poorer health-related quality of life, more pain and more depression, than those without such use.

In all, our studies showed that older patients are vulnerable to effects of addictive medications and that dependence on these is common in this group. Especially the oldest patients using many different medications are at risk. This information is important for all physicians treating older patients.

Additional information

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Published Aug. 24, 2020 11:31 AM - Last modified Sep. 11, 2020 12:57 PM