When Shawna Hignett woke up one January afternoon in 1995, her husband, John, was sitting on the bed beside her. He thought she had collapsed from the fumes while cleaning the oven and suggested they get some fresh air. Two months later she collapsed again, just after picking up the phone. But this time the then 24-year-old Saskatoon resident was taken to hospital, and doctors confirmed she had epilepsy, a neurological disorder that causes seizures and affects less than one per cent of the Canadian population.

"It was the phone ringing that triggered that second seizure," says Shawna, a mother of three. "In that same year in July it happened again. I was in a tailor shop and his phone rang. It was the exact same phone I had at home, and when his phone rang, I went down."

Dr. Nathalie Jetté, an assistant professor of neurology at the University of Calgary, says Shawna's reaction to the phone ringing is called a reflex seizure. "The seizure can consistently be provoked by an external stimulus or even an internal mental process," she says. But that doesn't explain the cause.

In Shawna's case, doctors aren't sure why she developed epilepsy, which isn't unusual. She didn't suffer from any of the known causes: stroke, head trauma, or brain tumour or infection. In less than one per cent of cases, epilepsy is inherited. "In 50 per cent of cases, we don't find the cause," says Jetté, whose brother has epilepsy.

During a CAT scan, doctors found a small cyst, not even two centimetres wide, in Shawna's right anterior temporal lobe. Her neurologist says there's nothing to indicate the cyst is the cause of her epilepsy. Shawna believes her epileptic seizures are related to hormones. "When the first three seizures occurred, they were during my period," says Shawna. She may be on to something.

Hormonal links
"Most studies done in animals and women show that estrogen tends to increase the risk of seizures, whereas progesterone is protective against seizures," says Jetté. During the menstrual cycle, estrogen increases around the time of ovulation, and some women have noted an increase in seizure frequency at that time. As well, just before and during a period, progesterone decreases, and some women may experience an increase in seizure frequency then. Catamenial epilepsy, in which the seizures are related to the menstrual cycle, affects only about 30 per cent of women with epilepsy. Nevertheless, it's a good idea for every woman with epilepsy to keep a seizure diary, says Jetté. "In this diary, she should keep track of her periods."

Even though female hormones may be one of the causes of seizures, women are not more prone to epilepsy than men. In a study published in the October 2005 issue of The Lancet Neurology, it was found that the incidence of epilepsy was similar in males and females. "The hormones can increase the frequency of the seizures, but are rarely the sole cause of the seizures," says Jetté. More research is necessary to understand the full role of hormones in epilepsy, she says.

Page 1 of 3

Cause and effect
All seizures happen because of a sudden change in the way the brain cells send electrical signals to one another. Most seizures are categorized as either partial or generalized. Partial seizures describe those that occur when there's a disturbance in one area of the brain, such as in the temporal lobe. Symptoms may include unusual sensations, hallucinations involving vision or smell, dizziness or jerky movements of one part of the body. A person experiencing such a seizure may or may not lose awareness of her surroundings.

Generalized seizures occur when the electrical disturbance involves the entire brain. There are several types of these, such as an absence seizure, during which a person loses awareness and may appear to be blinking and starring into space, and a tonic-clonic seizure, which is characterized by a person falling, muscles stiffening and the whole body convulsing.

Lynn Foeller, 44, was diagnosed with epilepsy and experienced tonic-clonic seizures when she was six years old. She has experienced absence seizures throughout her life, and in 1999 the tonic-clonic seizures reappeared. She was under a lot of stress at the time, which is a common trigger. Other triggers include failure to take epilepsy medication, lack of sleep, illness or fever, excessive use of or withdrawal from alcohol and use of illegal drugs.

"There are a lot of misconceptions about epilepsy," says Lynn, who lives in Cobourg, Ont. "Just because someone has epilepsy doesn't mean she's going to fall down and lose control." Lynn has kept her epilepsy a secret because of such misunderstandings. "If people didn't know what they were looking for, they wouldn't pick up on it," she says. But things changed with the return of the tonic-clonic seizures, which she experienced on her way to work one morning. She stopped working because it was too dangerous for her: she worked as a lab technician and regularly handled acids; she walked up 20 concrete stairs each day and falling could cause an injury; and she was struggling with temporary memory loss, a common side-effect of anti-epileptic drugs (AEDs).

Lynn also takes precautions in her personal life. After a tonic-clonic seizure, for example, she avoids visiting friends because her vocabulary is confused for a few days. She never drives or uses anything sharp, such as an electric knife or her husband's electric tools. She never climbs a ladder or swims in the pool without her husband close by.

Jetté says people with epilepsy can take part in most activities, though it can depend on the type of seizures they experience. All people with seizures involving loss of consciousness should avoid taking a bath, swimming alone, scuba diving and height-related activities, such as rock climbing. But an activity they shouldn't be afraid of is starting a family.

Family planning
Shawna's seizures began two years after the birth of her first son, but she didn't let the epilepsy stop her from having two more healthy children. But there are risks that women with epilepsy must consider before starting a family.

Dr. Eva Andermann is the director of neurogenetics at the Montreal Neurological Institute and Hospital and a professor in the departments of neurology and neurosurgery and human genetics at McGill University in Montreal. For more than 30 years she has been studying the outcomes of pregnancy in women with epilepsy who are also taking AEDs. During a study recently presented to the American Epilepsy Society, 96 children between the ages of six and 16 and born to mothers with epilepsy were monitored. Andermann says that while the numbers aren't big enough to determine the effects of all the different AEDs (there are close to 20 epilepsy medications on the market), many of these children's IQs are eight to 10 points lower than average. She says it's important to "minimize the number of drugs because overall it seems the decreased IQ is more related to the drugs than the seizures or the epilepsy." Andermann adds that a woman with epilepsy needs to discuss medication and family planning with her neurologist at least six months before trying to get pregnant.

As far as Shawna can determine, her epilepsy medication has had no effect on her kids -- Jonathon, Mark and Breann. "Epilepsy will change your life," she says, "but you can still have a family, career or whatever it is that makes life fulfilling to you."

Page 2 of 3

Medications
The most common therapy for epilepsy is anti-epileptic drugs (AEDs), which represent several classes of medications. New areas of concern for people taking AEDs include the following.

• Bone health
"We're finding that some AEDs may be associated with decreased bone density," says Dr. Nathalie Jetté of the University of Calgary. She suggests AED-users talk to their doctor about taking 1,000 to 1,500 milligrams of calcium and 400 international units of vitamin D daily.

• Low folate levels
Jetté suggests taking at least 0.4 milligrams of folic acid daily.

• Depression
"At least 30 per cent of people with epilepsy suffer from depression," says Jetté. She suggests individuals with epilepsy inform their physician if they are experiencing any psychiatric symptoms, such as depressed mood, anxiety or psychosis, because some AEDs can aggravate these symptoms.

• Birth control
Certain AEDs can increase the metabolism of the birth control pill, says Jetté, eliminating it faster from the body and providing an inadequate level of protection. Inform your physician if you are using any hormonal contraception because you may need a higher dose of birth control to provide adequate protection against pregnancy.

Surgical therapy
A study from London, Ont., published in the New England Journal of Medicine found that in patients with temporal lobe epilepsy (a type of partial epilepsy), surgery was more effective than anti-epileptic drugs (AEDs). The surgery involves removing the anterior part of the temporal lobe. About 50 to 60 per cent of seizures are partial seizures, with the majority being temporal lobe seizures.

At the end of one year, 58 per cent of patients who had epilepsy surgery were free of seizures compared with eight per cent in the group treated by AEDs alone. New surgical therapies for any type of partial epilepsy, including temporal lobe, are under investigation.

• Deep brain stimulator, an implanted device, delivers electrical stimulation to regions deep inside the brain.

• Responsive neurostimulator, a device about twice the size of a loonie, is implanted under the scalp and connected to one or two wires in the brain, where the seizures originate. When a seizure is detected, it delivers a mild electrical stimulation in an attempt to stop the seizure.

First aid for seizures
Most seizures are undetectable. Someone experiencing an absence seizure may just blank out for a few seconds. But if you see a person experiencing a more physical seizure, which can be frightening to watch, the following tips from Living Well with Epilepsy, available through the B.C. Epilepsy Society's website, will help you keep that person safe. Keep in mind that the person having the seizure may not hear you and may not be conscious of his actions.

• Ease him to the floor, if necessary. Move any hot, hard or sharp objects away. Loosen tight neckwear. Protect his head and body from injury.

• Do not restrain him or insert anything into his mouth.

• When the seizure is over, roll him onto his side to keep the air passage open and help his breathing.

• Stay with him until he has recovered completely.

• Seek medical attention immediately if the seizure lasts longer than five minutes or if the seizure repeats without a full recovery.

For more information about epilepsy, visit the following websites.
• Epilepsy Canada: www.epilepsy.ca
• The Canadian Epilepsy Alliance: www.epilepsymatters.com

Page 3 of 3