Social Psychiatry and Psychiatric Epidemiology

, Volume 52, Issue 11, pp 1425–1434 | Cite as

Comorbid psychopathology and everyday functioning in a brief intervention study to reduce khat use among Somalis living in Kenya: description of baseline multimorbidity, its effects of intervention and its moderation effects on substance use

  • Marina Widmann
  • Bernice Apondi
  • Abednego Musau
  • Abdulkadir Hussein Warsame
  • Maimuna Isse
  • Victoria Mutiso
  • Clemens Veltrup
  • David Ndetei
  • Michael OdenwaldEmail author
Original Paper


Background and aims

Migration and khat use were found to correlate with high rates of psychopathology. In this paper we aimed for assessing baseline multimorbidity and its interactions with a Brief Intervention.


In the RCT, 330 male Somali khat users were assigned to treatment conditions (khat use is a predominantly male habit). The ASSIST-linked BI for khat users was administered. Using the TLFB Calendar, the PHQ-9, a Somali short version of the PDS and parts from the CIDI, khat use and comorbidity was assessed. With a regression analysis we tested for the influence of comorbidity and with mixed effect models group differences over time in sleep duration, khat use-time and everyday functioning.


We found high rates of baseline multimorbidity: 51% (N = 168) for depression, 22% (N = 74) for PTSD and 23% (N = 73) for khat-psychotic symptoms. Depression and khat-psychotic symptoms, but not PTSD symptoms decreased without group differences. Khat use-time decreased and functional time increased with significant time × group interactions (p ≤ 0.046). Depression and PTSD did not influence therapy success but in participants without comorbid psychopathology, more khat use reduction after the intervention was found (p = 0.024).


Somali khat users in Kenya are highly burdened by multimorbidity of depression, PTSD and khat-psychotic symptoms. The main effects for time and differences in healthy vs. mentally ill khat users indicate potential of unspecific support and the specific need for mental health care in combination with substance abuse treatment. The increase of everyday functioning promises more options for alternative activities, preventing excessive use and addiction.


Khat use Somali refugees Brief Intervention Depression Posttraumatic stress disorder 


Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Marina Widmann
    • 1
    • 2
  • Bernice Apondi
    • 3
  • Abednego Musau
    • 3
  • Abdulkadir Hussein Warsame
    • 4
  • Maimuna Isse
    • 4
  • Victoria Mutiso
    • 3
  • Clemens Veltrup
    • 5
  • David Ndetei
    • 3
    • 6
  • Michael Odenwald
    • 1
    • 2
    Email author
  1. 1.University of KonstanzKonstanzGermany
  2. international e.V.KonstanzGermany
  3. 3.Africa Mental Health FoundationUpperhill NairobiKenya
  4. 4.Tawakal Medical ClinicNairobiKenya
  5. 5.Fachklinik Freudenholm-RuhlebenPlönGermany
  6. 6.University of NairobiNairobiKenya

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