Blog # 109: ANOTHER STUDY SHOWS DOGS CAN SMELL WHEN SEIZURES ARE ABOUT TO BEGIN==MORE SAFETY

Researchers ¹ find dogs can somehow detect a telltale scent linked to epileptic seizures. Can they be trained to warn owners when seizures are imminent? If so, this can add to the patient’s independence, confidence and safety in avoiding injury. They could then seek aid more expeditiously, too.

Dogs are known to detect odors of some cancers, diabetes and malaria. For example, the composition of exhaled breath is different in patients with lung cancer, inflammatory lung or liver disease, kidney dysfunction or diabetes.²

There is also anecdotal evidence they can sense that their owner may be about to have a seizure, though this was poorly understood until now.

Researchers in France used five dogs in a study to sniff out a scent specifically linked to a human seizure. They presented the dogs with a variety of smells taken from epileptic patients, including body odors emitted during calm activity, while exercising, and during an attack.

Three dogs identified the seizure scent 100 percent of the time, while two others sniffed out the right sample in two out of three challenges.

“The results went beyond our expectations by showing that there is indeed a general odor of an epileptic seizure,” the lead University of Rennes French researcher, Dr. Amelie Catala, said. “We hope it will open new lines of research that could help anticipate seizures and thus get patients to seek security.”

Dogs’ noses have evolved to be highly sensitive, and can detect specific organic compounds at a concentration of less than 0.001 parts per billion. The most sophisticated current “electronic noses”, meant to pick up potentially harmful odors that humans can't smell, have a detection threshold of around 300 parts per billion.

Catala said that while dogs had been shown previously to be able to sniff out chronic diseases, this experiment showed they could potentially diagnose acute health episodes that last just a few minutes. This constitutes a first proof that, despite the variety of seizures and individual odors, seizures are associated with olfactory characteristics. These results open a large field of research on the odor signature of seizures. Further studies will aim to look at potential applications in terms of anticipation of seizures.

“The study of odors by the use of dogs constitutes a fast, low-cost, non-invasive, and effective screening method of diseases that can be difficult to identify normally,” she said.

1. Catalia A, Grandgeorge M, Schaff J-, et.al. Dogs demonstrate the existence of an epileptic seizure odor in humans Scientific Reports volume 9, Article number: 4103 (2019)

2. Buszewski B., Kesy M., Ligor, T.  Human exhaled air analytics: biomarkers of diseases. Biomed. Chromatogr. BMC 21, 553–566 (2007).

 
Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. “DINGS” is his first novel. It is a mother’s dramatic story that teaches epilepsy, now available in eBook, audiobook and soft cover editions.

Blog #108: SUDEP—SUDDEN DEATH IN EPILEPSY―OCCURS IN ALL TYPES OF EPILEPSIES

            SUDEP, sudden death in epilepsy, has an incidence of 1-2 cases per 1,000 patients with epilepsy per year.¹

            The recent tragic death of Cameron Boyce, a popular 20 year-old Disney star, has brought SUDEP and epilepsy to the public eye.

            A study reviewed 237 SUDEP cases between October 2011 and June 2017 in the North American SUDEP Registry. Subjects were ages 1-70 years, the median age was 26. Women made up 38% of the study population.²  Researchers found that night sleep, usually considered the usual situation related to SUDEP deaths, is not necessarily the most common time when SUDEP occurs. Many patients in this registry died during daytime. Additionally, the mechanism of death may not be due to an obstruction of the airways but more likely is related to cardio-respiratory phenomena.

            The study showed all ages and all epilepsy severeties are affected by SUDEP; it is not restricted to chronic poorly-controlled epilepsies. Anybody with epilepsy can experience SUDEP including patients with well-controlled or benign epilepsies, i.e., those with centrotemporal EEG spikes (the Rolandic Epilepsies that primarily occur during sleep and not while awake). The reported lifetime number of generalized tonic-clonic grand mal seizure counted in the study population ranged from zero to more than 500.

            The most notable observation in the study was that a majority of these deaths occurred in people who did NOT take their last dose of antiseizure medication. This presents a chance to minimize the risk of SUDEP. Take your medications as prescribed!

            Physicians need to discuss the risk of SUDEP with their patients, emphasizing the importance of never skipping an antiseizure medication dose. If your doctor doesn’t bring SUDEP up, YOU, the patient, should ask about it. Minimize alcohol and, additionally, get enough sleep.

            Epilepsy surgery can be curative of epilepsy if you are a candidate. Discuss this option with your doctor. The shorter time interval between the onset of your epilepsy and the epilepsy surgery can achieve better results from surgery.³

1)      Thurman DJ, Hesdorffer DC, French JA. Sudden unexpected death in epilepsy: assessing the public health burden. Epilepsia 2014;55: 1479-85.

2)      Verducci C, Hussain F, Donner E et. al. SUDEP in the North American SUDEP Registry: the full spectrum of epilepsies. Neurology 2019;93:e226-e236.

3)      Bjelivi J, Olsson I, Malmgren K, et. al. Epilepsy duration and seizure outcome in epilepsy surgery. Neurology 2019;93:e159-e166.

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. “DINGS” is his first novel. It is a mother’s dramatic story that teaches epilepsy, now available in eBook, audiobook and soft cover editions.

Blog # 107: A FAMILY DEALS WITH UNRECOGNIZED EPILEPSY

Excerpted from Dr. Lance Fogan’s novel, DINGS  Chapter 23, Part 1

I rarely remembered my dreams, but the images that woke me the night before Conner’s neurology appointment were a nightmare: a horse was chasing me, and no matter how fast I ran I could still feel its steamy breath on the back of my neck. I slipped and fell into an open pit and suffocated at the bottom.

My eyes sprang open. My pillow was damp. I gasped for air and understood: the images represented Conner’s crisis. My mind whirred with questions: what would the neurologist find today? What would he do? Could Conner have a brain tumor, after all?

I couldn’t let go of the deep terror I had felt ever since his seizure. Moreover, it wasn’t just Conner’s seizure; it was our seizure. My seizure. I clasped my sweaty hands on my chest and stared at the ceiling.

I could no longer fight that other memory that was starting to haunt me: Sheila Braun lived next-door to me for a short time when I was in high school. She had epilepsy. She even had to stop driving. I remembered how she sobbed as she told me that she was afraid to have children because she might pass it on when she got married—if ever she got married. I remembered our horror as she showed me awful pictures of epileptics in asylums from a long time ago. I cried with her. I hadn’t thought of Sheila in years.

***

I moved robot-like all morning. I stared at the wall and then out the window. I walked toward the bathroom, stopped, shook my head and turned back to the kitchen. A couple of times I opened the refrigerator and just stood there. Then I closed it without taking anything out. I had to make sure that I had thought of all the questions I was going to ask the neurologist that afternoon. I wandered back to the sink and leaned against the kitchen counter. I clicked my fingernails against my coffee cup and stared out the window.

“Sandra, are you okay?”

I looked at Sam. “This is making me crazy!”

“Sandra—”

“I’ll be right back.” I bolted out of the kitchen and rushed upstairs.

A moment later I was at my desk, pen in hand. I reached for the paper with the questions I had written down days ago. I chewed the end of my pen and reconsidered my questions:

1.   Will Conner ever be normal again? The doctors had warned us that he could have another seizure. Now he was taking those pills with all of those side effects. Would the medicines change him from the sweet little boy that we all knew?

2.   Will people treat him like a freak? Ever since Conner’s seizure, Sam and I had become very cautious around our son. I would gladly have kept Conner home from school or even home-schooled him until he had the appointment with the neurologist. Even Sam had started to coddle the boy: he didn’t let Conner play touch football or soccer or even ride his bike with his friends. That wasn’t like Sam. I was worried that other children would make fun of Conner now.

3.   Could Madison have a seizure? I had read that seizures could run in families; that epilepsy was sometimes passed along genetically. Sam’s brother had one. Was it possible that seizures were contagious, like a cold?

4.   Does Conner have epilepsy?

I took a deep breath and leaned back in the chair. Getting answers to these questions would help me get a sense of control over this new craziness in my life. But would I actually gain control of Conner’s situation? Of that, I had no such delusion.

***

When I returned to the kitchen, Sam was sitting alone over his coffee. He seemed mesmerized by the shadows cast from the window blinds. The stripes just missed the morning paper spread out in front of him.

“Sam? Are you all right?”

“I’m trying not to focus on the appointment. If you must know, it’s all that I can think about.” He lifted the steaming cup to his lips. He leaned back in the chair and stretched his legs out. He stared straight ahead.

I wrapped my arms around his shoulders. “Yeah, I know. Me too.” I took the chair next to him.

“Conner had such a good day on Monday. The kids had been joking and giggling all throughout dinner. Sandra, do you remember how Conner began making those grotesque faces while he tried to knot that cherry stem with his tongue? You know, inside his mouth. The kids laughed so hard, gobs of their hot fudge sundaes sprayed out of both their mouths. Remember? Chopped nuts, whipped cream, ice cream and all. And when you scolded them, it just made them laugh harder. You couldn’t help laughing, too. That was so great.”

His smile faded. He turned the pages of the newspaper without looking down. “After today, do you think we will be able to laugh like that again?”

He stood up. “Okay. Gotta go. I have to visit the new construction site. I’ll be home by two; don’t worry. I won’t be late. I’ll say goodbye to the kids.” He kissed me and left.

***

Sam came home on time as he had promised. I approached Conner’s bedroom; his door was closed. I tried to remember how old I was when I began to shut my door against my parents’ intrusion. He didn’t answer my knock. “Conner, are you ready? It’s time to go.” He didn’t respond. “I’m coming in, honey.” I opened the door.

“I don’t want to go,” he protested. He sat cross-legged on the floor and didn’t look up at me.

“I know, honey. But Daddy and I will be with you. It’ll be all right. We want you to be able to stop those medicines if you don’t need them, and only this neurologist can decide that. He needs to talk to you and find out why that seizure happened.”

“I don’t want any needles!”

“I know. You’ve said that. You know that whenever you had to get a shot or a blood test, it wasn’t so bad. That’s how life is, Conner. Things usually are not as bad as you expect them to be.”

Conner began to hit the floor with both fists. “I’m not going! No! You go!”

Sam called from downstairs, “Let’s go, people! We don’t want to be late. Mrs. Hall just drove up to stay with Madison.”

“I’m not going!”

Sam bounded up the stairs and loomed over his son. “Conner, let’s go. Get up. Right now, son!” He scooped the boy into a standing position. “’Atta-boy!” Conner offered no further resistance—not when his father was in this mood.

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. “DINGS” is his first novel. It is a mother’s dramatic story that teaches epilepsy, now available in eBook, audiobook and soft cover editions.