New research published in Clinical Gastroenterology and Hepatology has revealed an area that has been neglected in driving safety law in many states of the US. A number of state laws are lacking in driving safety measures with regards to those people who drive with cognitive impairment; in fact only six of the 50 states contacted had laws which required drivers with medical impairments to report their conditions.
Increasingly the emphasis is falling to doctors to evaluate their patients for cognitive impairment conditions which could potentially affect their driving ability. Failure to do this could also have far reaching legal effects for the physician of an effected patient. Patients with liver disease, in particular cirrhosis, are prone to a type of cognitive impairment known as hepatic encephalopathy (HE) which can range in levels from mild to extreme.
Hepatic encephalopathy has a range of disabling effects such as selective attention, visuomotor ability and psychomotor speed, all of which can greatly impact a person's ability to drive. In the report it was found that mild HE is becoming a more common factor in traffic violations and also car accidents.
HE is not only limited to a person's driving ability, it can have far reaching consequences into many parts of a sufferers life. One incident of an HE episode can result in life-long cognitive defects which can often be very serious. Further research into this area using a test known as the Psychometric Hepatic Encephalopathy Score (PHES), has also established that HE is a condition that cannot be fully reversed and therefore needs to be addressed.
The doctors who have carried out the most recent research suggest that at the very least, it is the responsibility of the physician and health-care workers to examine and evaluate those patients suffering from cirrhosis so that they are able to determine whether any degree of HE is at work.
If this is found to be the case then it is recommended that the doctors discuss any driving issues with the patients to ensure the safety of both the patients and other road users. It is also hoped that this research will also provide a starting point for the re-evaluation of driving safety laws in the United States.