title: Bipolar spectrum disorders in a clinical sample of patients with Internet addiction: hidden comorbidity or differential diagnosis?
abstract: OBJECTIVE
  Behavioral addictions and bipolar disorders have a certain probability of co-occurrence. While the presence of a manic episode has been defined as an exclusion criterion for gambling disorder, no such exclusion has been formulated for Internet addiction.
  
  
  METHODS
  A clinical sample of 368 treatment seekers presenting with excessive to addictive Internet use was screened for bipolar spectrum disorders using the Mood Disorder Questionnaire. Psychopathology was assessed by the Symptom Checklist 90R and a clinical interview was administered to screen for comorbid disorders.
  
  
  RESULTS
  Comorbid bipolar disorders were more frequent in patients meeting criteria for Internet addiction (30.9%) than among the excessive users (5.6%). This subgroup showed heightened psychopathological symptoms, including substance use disorders, affective disorders and personality disorders. Further differences were found regarding frequency of Internet use regarding social networking sites and online-pornography.
  
  
  CONCLUSIONS
  Patients with Internet addiction have a heightened probability for meeting criteria of bipolar disorders. It is not possible to draw conclusions regarding the direction of this association but it is recommended to implement screening for bipolar disorders in patients presenting with Internet addiction.
  
  
  CONCLUSIONS
  Similar to gambling disorder, it might prove necessary to subsume bipolar disorders as an exclusion criterion for the future criteria of Internet addiction.
authors.affiliation: Department of Psychosomatic Medicine and Psychotherapy, University Medical Centre, Johannes Gutenberg University Mainz , Mainz , Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Wölfling
authors.forename: Manfred E
authors.initials: ME
authors.lastname: Beutel
authors.forename: Michael
authors.initials: M
authors.lastname: Dreier
authors.forename: Kai W
authors.initials: KW
authors.lastname: Müller
mesh_terms: D000293:Adolescent; D000328:Adult; D016739:Behavior, Addictive / Q000453:epidemiology*; D001714:Bipolar Disorder / Q000453:epidemiology*; D002648:Child; D015897:Comorbidity; D003937:Diagnosis, Differential; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D020407:Internet; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology; D008875:Middle Aged; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Internet Addiction; Internet Gaming Disorder; bipolar spectrum disorders; clinical prevalence; comorbidity; diagnostic criteria