Public Defence: Stian Magnus Staurung Orlien Stian Magnus Staurung Orlien at Institute of Clinical Medicine will be defending the thesis “Catha edulis and chronic liver disease in eastern Ethiopia” for the degree of PhD (Philosophiae Doctor).

Photo: Theres Ønvik Lorentzen

Trial Lecture – time and place

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Adjudication committee

  • First opponent: Professor Mark Thursz, Department of Surgery and Cancer, Faculty of Medicine, Imperial Collage London, UK
  • Second opponent: Professor Odd Helge Gilja, Department of Clinical Medicine, Faculty of Medicine, University of Bergen
  • Third member and chair of the evaluation committee: Professor Kirsten Muri Boberg, Faculty of Medicine, University of Oslo

Chair of the Defence

Professor II Olav Dalgard, Faculty of Medicine, University of Oslo

Principal Supervisor

Senior Consultant Asgeir Johannessen, Oslo University Hospital


Chronic liver disease (CLD) is a major cause of morbidity and mortality worldwide. In Africa, the relative burden of CLD by aetiology is largely unknown although hepatitis B virus, alcohol misuse and hepatitis C virus are thought to be major causes. CLD has recently been reported as the leading cause of mortality in adults in eastern Ethiopia, but no studies exploring the aetiological spectrum of CLD are available, and hence, relevant preventative measures cannot be implemented.

This work set out to explore the aetiological spectrum of CLD in eastern Ethiopia and assess potential risk factors for the development of CLD, including the habitual use of khat (Catha edulis).

The results of this thesis are based on three studies of 150 patients with CLD and 300 control subjects without CLD. The diagnosis of CLD was established by clinical and radiological criteria. All study subjects were assessed using a semi-structured interview, standardized clinical examination and extensive laboratory testing.

We found that approximately one third of CLD in eastern Ethiopia was attributed to chronic HBV infection, whereas alcoholic liver disease and chronic HCV infection was rare. Interestingly, after ruling out viral hepatitis, alcohol misuse, autoimmune liver disease, metabolic liver disease and parasitic infections, the underlying aetiology of CLD in eastern Ethiopia was still unexplained in more than 50% of the patients. Simultaneously, we found that more than 80% of the CLD patients used khat on a daily basis.

Overall, a significant association was found between khat use and the risk for developing chronic liver disease, particularly in men; this risk was strong (adjusted odds ratio 5.67; 95% confidence interval 1.85-17.37) and dose-dependent, suggesting a causal relationship. Given the assumption of causality, more than 80% of CLD among men in this region is attributable to khat chewing.

Since khat is increasingly available and habitual khat chewing is expanding worldwide, the health consequences of khat use, both on an individual and a public health level, are profound.

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Published Feb. 18, 2019 9:36 AM - Last modified Feb. 18, 2019 11:28 AM