Cause of alcohol dependence may be visible with molecular imaging

Researchers may have found a clearer understanding of what causes alcohol dependence, according to a new study published in the Journal of Nuclear Medicine (JNM).  

"These findings provide first human in vivo evidence for a role of limbic mGlu5 in the pathophysiology of alcohol dependence, possibly involved in a compensatory mechanism helping to reduce craving during abstinence," said lead author of the study Gil Leurquin-Sterk from the Department of Imaging and Pathology at KU Leuven University in Leuven, Belgium. 

The study aimed to investigate the availability of mGlu5 in the brains of alcoholic dependent patients using F-FPEB positron emission tomography.  

Researchers performed 90-minute 18F-FPEB scans combined with arterial blood sampling in 16 recently abstinent alcohol-dependent patients and 32 age-matched controls.   

"Regional mGlu5 availability was quantified by the 18F-FPEB total distribution volume using both a voxel-by-voxel and a volume-of-interest analysis with partial-volume effect correction," Leurquin-Sterk added. "Alcohol consumption within the last three months was assessed by questionnaires and by hair ethyl glucuronide analysis. Craving was assessed using the Desire for Alcohol Questionnaire."   

According to study results, the researchers concluded the following:  

• mGlu5 availability was lower in mainly limbic regions of alcohol-dependent patients compared to controls (P<0.05, family-wise error corrected), ranging from 14% in the posterior cingulate cortex up to 36% in the caudate nucleus.
• Lower mGlu5 availability was associated with higher hair ethyl glucuronide levels for most regions, and was related to a lower level of craving specifically in the middle frontal gyrus, cingulate cortex and inferolateral temporal lobe.