Under new rules introduced in March last year, all WA drivers must notify the department "as soon as practicable" of a range of medical conditions that have the potential to affect driving ability - from reducing perception, judgment and response time to general physical capability.
The broad list of conditions which the department says needs to be reported includes diabetes, heart disease, chronic arthritis, sleep apnoea, attention deficit and hyperactivity disorder, high or low blood pressure, giddiness, lung disease and depression.
Other conditions on the list are those with obvious impairment issues such as stroke, epilepsy, glaucoma, cataracts and macular degeneration, drug and alcohol dependency, Parkinson's disease and Alzheimer's.
But the implications of not reporting your medical conditions may be so mild that many drivers will choose not to inform the department.
Since the rules were introduced, the department said about 7000 West Australians had notified it of medical conditions, but many thousands more might be driving unaware of their obligation.
The change was made in response to recommendations made by the State Coroner after a fatal road accident in which a driver was killed after colliding with another driver who had been having an epileptic seizure.
Initially, the coroner recommended just people with epilepsy report their conditions, however this has been widened, bringing WA into line with other States and Territories.
A spokesman for the department said reporting a condition did not necessarily mean any restrictions would be placed on a person's ability to drive.
"It may lead to a provision being added, for example there may be a stipulation that a medical assessment is required prior to renewal or that medication is to be taken as prescribed," he said in a statement.
"No specific medical information about the condition or treatment will be added to the licence card."
The department insists that all medical information will be kept private, "and is available only to a very limited number of key transport personnel for the sole purpose of determining a person's fitness to drive".
This includes not informing insurance companies of specific medical conditions, even if the driver is involved in an accident.
"All information in relation to a driver's medical condition is kept by the Department of Transport in the strictest confidence, and not released to anyone, including insurance companies," the spokesman said.
"Notations in relation to requirements such as optical aids and the requirement to take medication are made on the driver's licence card but with no reference to the specific medical condition."
Insurers contacted by The West Australian said that - for now at least - not reporting a medical condition would not affect insurance claims.
If a driver does inform the department, however, and a variation is made to the licence, then a driver could invalidate a claim if they remained on the road without heeding the change.
The Insurance Commission of WA, which oversees all third-party injury claims, said a driver who continued to drive after the Department of Transport suspended or cancelled their licence would "suffer the consequences if they cause a crash which results in a personal injury claim".
However, "if they fail to declare a condition and are involved in a crash causing a personal injury claim, even though he/she would be liable for sanctions under the mandatory reporting legislation, there would be no breach of the (compulsory third party) policy as their driver's licence was current at the time the incident occurred. No such instances have been reported to ICWA."
RAC manager of technical claims Glen Walker said drivers were covered by insurance provided they were abiding by the relevant laws for driving a vehicle, meaning non-disclosure of medical conditions would not invalidate their insurance.
"We are reviewing our position at the moment," he said. "It is expected an amendment to the insurance product disclosure statement will reflect the legislation, that drivers are obliged to disclose their medical conditions to the department."
A report provided by the WA Comprehensive Epilepsy Service to the coroner at the time of the seizure inquiry noted that while epilepsy and diabetes were factors in some road accidents, they together represented the cause of around one in every 200 traffic deaths in the US, while heart conditions were responsible for eight in 200 traffic deaths.
Alcohol was responsible for a third of deaths.
WA Police spokesman Sgt Graham Clifford said a few road deaths each year could be linked clearly to medical conditions, but such factors were not always obvious.
Clinical Professor John Dunne, a consultant neurologist at RPH, said mandatory medical reporting by drivers made good sense and doctors who saw drivers with deteriorating mental or physical health were now able to remind them of their legal obligation to report their conditions.
But Dr Dunne said any move to require doctors to report their patients' conditions should be resisted as it would undermine the doctor-patient relationship and make people less likely to seek treatment.
Ruth Callaghan, The West Australian November 12, 2009, 6:00 am