Minimal hepatic encephalopathy matters in daily life

Minimal hepatic encephalopathy is a neuro-cognitive dysfunction which occurs in an epidemic proportion of cirrhotic patients,estimated as high as 80% of the population tested. It is characterized by a specific,complex cognitive dysfunction which is independent of sleep dysfunction or problems with overall intelligence. Although named "minimal",minimal hepatic encephalopathy(MHE) can have a far-reaching impact on quality of life,ability to function in daily life and progression to overt hepatic encephalopathy. Importantly,MHE has a profound negative impact on the ability to drive a car and may be a significant factor behind motor vehicle accidents. A crucial aspect of the clinical care of MHE patients is their driving history,which is often ignored in routine care and can add a vital dimension to the overall disease assessment. Driving history should be an integral part of care in patients with MHE. The lack of specific signs and symptoms,the preserved communication skills and lack of insight make MHE a difficult condition to diagnose. Diagnostic strategies for MHE abound,but are usually limited by financial,normative or time constraints. Recent studies into the inhibitory control and critical flicker frequency tests are encouraging since these tests can increase the rates of MHE diagnosis without requiring a psychologist. Although testing for MHE and subsequent therapy is not standard of care at this time,it is important to consider this in cirrhotics in order to improve their ability to live their life to the fullest.

Impact of smoking cannabidiol (CBD)-rich marijuana on driving ability

To investigate effects of smoking cannabidiol(CBD)-rich marijuana on driving ability and determine free CBD andΔ9-tetrahydrocannabinol(THC)concentrations in capillary blood samples,a randomised,double-blind,placebo-controlled,two-way crossover pilot study was conducted with 33 participants.Participants smoked a joint containing 500 mg of tobacco and either 500 mg of CBD-rich marijuana(16.6%total CBD;0.9%total THC)or 500 mg of a placebo substance,then performed three different dimensions of the Vienna Test System TRAFFIC examining reaction time,behaviour under stress,and concentration performance.For further assessment of participants’fitness to drive,three tests of balance and coordination were evaluated and vital signs(blood pressure and pulse)were measured.Dried blood spot samples of capillary blood were taken after smoking and after completion of the tests to determine the cannabinoid concentrations(CBD,THC and THC-metabolites).The results revealed no significant differences between the effects of smoking CBD-rich marijuana and placebo on reaction time,motor time,behaviour under stress,or concentration performance.Maximum free CBD and THC concentrations in capillary blood were detected shortly after smoking,ranging between 2.6-440.0 ng/mL and 6.7-102.0 ng/mL,respectively.After 45 min,capillary blood concentrations had already declined and were in the range of 1.9-135.0 ng/mL(free CBD)and 0.9-38.0 ng/mL(free THC).Although the observed levels of free THC concentrations have been reported to cause symptoms of impairment in previous studies in which THC-rich marijuana was smoked,no signs of impairment were found in the current study.This finding suggests that higher CBD concentrations cause a negative allosteric effect in the endocannabinoid system,preventing the formation of such symptoms.Nevertheless,it is recommended that consumers refrain from driving for several hours after smoking CBD-rich marijuana,as legal THC concentration limits may be exceeded.