Transient ischemic attack in heavy cannabis smokers - How 'safe' is it?

Drugs are lately considered high-risk factors for cerebrovascular disease. Three male patients (mean age 24.6 years) who were heavy cannabis smokers p resented with transient ischemic attacks (TIA) shortly after cannabis abuse . The complete examination of all 3 consisted of: EEG, brain CT scan, brain MRI, cerebral vessel angiography (digital subtraction and magnetic resonan ce angiography); also a full cerebrospinal fluid, urine and blood analysis (immunological, biochemical and hormonal tests were included). Urine was fu rther examined for drug metabolites. An extensive cardiological investigati on was carried out. Small vessel leukoencephalopathy was revealed by the br ain CT and MRI. EEG recordings of the first patient showed paroxysmal sharp waves with left hemispheric dominance. The other 2 patients had diffuse de lta and theta activity in their EEG tracings. The urine analysis was positi ve for cannabis metabolites. There were no other abnormal findings in the r est of the meticulous and thorough study of all 3 patients, which leads to the conclusion that cannabis was the only risk factor responsible for the o bserved TIA, contradictory to other stud ies, which support that cannabis i s a 'safe' drug. More research is required in order for this issue to be co mpletely elucidated. Copyright (C) 2000 S. Karger AG, Basel.