title: Are the effects of cannabis dependence on glucose metabolism similar to schizophrenia? An FDG PET understanding.
abstract: BACKGROUND
  Cannabis has been associated with transient psychotic states; however, the causal relationship between cannabis and schizophrenia continues to remain a matter of debate. Epidemiological and some biological studies hint at cannabis being an independent risk factor for schizophrenia; this has not been definitively proved.
  
  
  OBJECTIVE
  We aimed to understand the patterns of glucose uptake in important brain regions among individuals with cannabis dependence and schizophrenia. Furthermore, we compared the interregional metabolic rates in pertinent neural circuits among individuals with cannabis dependence, schizophrenia and normal controls.
  
  
  METHODS
  This is a case-control cross-sectional study that was carried out by a general psychiatry department in collaboration with a nuclear diagnosis unit.
  
  
  METHODS
  Male volunteers with cannabis dependence, schizophrenia and normal controls underwent FDG PET scanning. Glucose uptakes in pre-selected regions of interest were compared using MANOVA. Finally, Chow tests were used to compare interregional metabolic relationships in the mesocortical and cortical-subcortical-cerebellum circuits.
  
  
  RESULTS
  Significant differences (P<0.05) were noted among individuals with cannabis dependence and schizophrenia in the medial and lateral temporal regions. When the neural circuits were compared, significant interregional differences (P<0.05) were noted between individuals with cannabis dependence and normal controls. However, among individuals with cannabis dependence and schizophrenia, no significant differences (P>0.05) were noted in these patterns.
  
  
  CONCLUSIONS
  Our findings suggest that cannabis dependence can alter interregional relationships in a manner similar to schizophrenia. This indicates that cannabis could potentially play a role in the development of psychosis by altering neural circuits.
authors: Department of Psychiatry, G. S. Medical College and King Edward Memorial Hospital, Mumbai, India.
authors: Shubhangi R
authors: SR
authors: Parkar
authors: Seethalakshmi
authors: S
authors: Ramanathan
authors: Narendra
authors: N
authors: Nair
authors: Shefali A
authors: SA
authors: Batra
authors: Shilpa A
authors: SA
authors: Adarkar
authors: Purushottam
authors: P
authors: Kund
authors: Nawab Singh
authors: NS
authors: Baghel
authors: S H
authors: SH
authors: Moghe