Excessive Sleepiness in Daytime Hours Linked to Worse ALS Symptoms in Study

Excessive Sleepiness in Daytime Hours Linked to Worse ALS Symptoms in Study

Strong feelings of being sleepy during daytime hours are much more common in amyotrophic lateral sclerosis (ALS) patients than the general public, and appear to be associated with poorer cognitive skills and greater behavioral problems, a study from China reports.

Its researchers suggested that their findings, if confirmed in larger studies, could merit listing excessive daytime sleepiness as a “severe complication of ALS.”

The study, “Excessive daytime sleepiness in Chinese patients with sporadic amyotrophic lateral sclerosis and its association with cognitive and behavioural impairments,” was published in the Journal of Neurology, Neurosurgery & Psychiatry.

ALS affects several brain regions, causing not only motor dysfunction, but also cognitive impairment, behavioral changes, and sleep disturbances. Evidence suggests that about half of ALS patients have difficulties with cognitive and/or behavior.

Excessive daytime sleepiness (EDS) is estimated to affect between 2.5 and 9.0 percent of adults worldwide. It is characterized by persistent sleepiness and feeling of overwhelming fatigue in daytime hours, even with apparently adequate nighttime sleep.

EDS often interferes with work, school, and relationships, and can impair quality of life and cognitive function. While its underlying mechanisms are unclear, EDS has been associated with such psychiatric and neurodegenerative disorders as Alzheimer’s and Parkinson’s disease. But it has not been studied widely in ALS.

Researchers in Beijing decide to assess EDS frequency and its potential association with cognitive or behavioral problems in ALS. They recruited 121 patients and 121 age- and sex-matched healthy individuals, and assessed EDS using the Epworth Sleepiness Scale (ESS), a self-administered questionnaire that measures daytime sleepiness.

Patients (71 men and 50 women) had a mean age of 53, and disease severity was evaluated through the revised ALS Functional Rating Scale (ALSFRS-R).

Evidence of other sleep disorders was assessed through face-to-face interviews; cognition, behavior, depression, and anxiety were evaluated using validated tests.

Patients were found to have a significantly higher frequency of EDS (26.4%) than healthy individuals (8.3%), as well as significantly more severe EDS symptoms, suggesting an association between the two conditions.

Further analysis revealed ALS patients were at a four times increased risk of developing EDS, compared with healthy people.

EDS was diagnosed in 32 ALS patients, and they showed significantly worse overall ALS severity, including physical limitations like greater difficulties in moving in bed and adjusting bedclothes, compared to the 89 patients without an EDS diagnosis.

But ALS patients with EDS showed no significant differences in lung function to other patients, supporting evidence that suggests sleep disturbances are not dependent on lung health in ALS.

“The higher frequency of EDS symptoms in patients with ALS is not entirely due to nocturnal sleep quality and respiratory issues; rather, the neurodegenerative process itself seems to be involved,” the researchers wrote.

ALS patients with EDS also showed significantly worse cognitive abilities — particularly in memory — and behavioral changes than those without EDS, suggesting EDS may promote progression in these symptoms.

The researchers noted that larger studies are needed to confirm these associations, and — if confirmed — EDS could be “considered a severe complication of ALS,” as it appears to be linked to more severe overall dysfunction and a wider range of affected brain areas.

They also pointed out that EDS symptoms in ALS patients remain under-diagnosed and untreated. More timely diagnosis of EDS, as well as better treatment, might help to improve quality of life for these people.

Marta Figueiredo holds a BSc in Biology and a MSc in Evolutionary and Developmental Biology from the University of Lisbon, Portugal. She is currently finishing her PhD in Biomedical Sciences at the University of Lisbon, where she focused her research on the role of several signalling pathways in thymus and parathyroid glands embryonic development.
Marta Figueiredo holds a BSc in Biology and a MSc in Evolutionary and Developmental Biology from the University of Lisbon, Portugal. She is currently finishing her PhD in Biomedical Sciences at the University of Lisbon, where she focused her research on the role of several signalling pathways in thymus and parathyroid glands embryonic development.
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  1. Aaron Knobloch says:

    This article explained a lot about my fatigue. it did not explain or even hint as to what behavioral & what the cognitive symptoms be.
    as a Pals for ± 8-10 years i have been been feeling slowly increasing fatigue for about ±3 years. but i’ve been feeling both behavioral & cognitive changes (decreasing ability to focus & difficulty in remembering things. both of these are difficult for me to assess whether qualitatively or quantitatively) for less than 2 years. factor in that i’m 70 & have been diagnosed with diabetes, as well as not being able to use my arms & legs for about 5 years. i sometimes feel a little more than frustrated!
    can anything be done? sorry about the rant. guess i needed it.

  2. Gus schuetz says:

    I’m a 73 yr old retired head and neck surgeon. Dx was made 18 mo ago. Initially I noticed my legs losing muscle about 8 yrs ago. I told my primary care physician and was seen by a neurologist. No diagnosis was made except peripheral neuropathy due to leg pains. Fasciculations in my legs with cramps concurrently. I was told that it was nothing but old age creeping at the door. No tests and pain pills if needed at night.
    I kept going because otherwise I felt normal. Years went by with slow deterioration. I noted in 2015 that my hands were slightly smaller. Down from eight and a half surgical gloves to eight. I took a picture to document.
    I was also losing weight from loss of muscle mass all over my body. I went from 225 lbs to 195 lbs and took a selfie flexing my muscles for documentation April 2017. My family and doctors did not believe me.
    Approximately 30 mo. Ago I started noting that my voice was higher pitched but nobody noticed it. My family and friends said no change. I then spoke with an old girlfriend and she said that she remembered my voice being much lower. I joked and said that my testosterone was probably in the tank. At the same time it was a confirmation of sorts. I told my neurologist again and he said that he would order an MRI of the brain. Many months went by so I went to talk with an oncologist friend of mine a couple of offices away. He ordered the MRI of my brain and it can back normal for age with a possible small CVA. I was actual happy to hear it. I retired just in case it was a stroke to protect my patients.
    Down deep I knew that it wasn’t a stroke but I wanted to believe it so I took my Xarelto like a good patient.
    I again ask my partners about my voice and they had not noticed any changes but when I would try to play guitar and sing, I could not carry a tune at all. So I went into work and had one of my PA’s perform a fiber optic laryngoscopy on me. He said that I had presbylarynges, old flaccid cords, and it otherwise looked normal. I thought that was surprising and decided to schedule a video so that I could see for myself. Time went by and I was too busy but ultimately became more concerned since I now noticed that I was starting to aspirate liquids. When I scheduled the video and looked at myself I saw the my cords were extremely flaccid and paralyzed in adduction(closed). At this point my voice could be heard as different by family and friends.
    I called the neurologist again and told him that I was really getting concerned. He told me to come over within the week. I did and the diagnosis of bulbar ALS was made.
    About three years before the diagnosis was made I suffered from an acute attack of gout. I thought that I might have had a bad dream and kicked the wall breaking my toe. After about 15 minutes I realized that I had gout. I then set out to change my diet instead of taking poison meds with all kinds of potential problems. I cut out almost everything except beer. I like to have a beer after jogging at night. I couldn’t jog with gout and so I quit drinking beer and tried a whiskey coke. I still would get gouty flares
    So I quit anything with alcohol. My uric acid levels dropped with my diet change and it was at that point that the ALS symptoms really took off.
    With what is known about ALS and uric acid, I think that I was treating myself all of those years with my diet high in purines.
    I’m now down to 154lbs and have a feeding peg. I can’t speak, eat or drink anything.
    I also have noted that I can sleep all day and night. I can still walk around but not far due to shortness of breath.
    My twitching is constant and more severe the more active I try to be.this leads to cramps in the muscles I didn’t know that I had.
    My diaphragm twitches and I get short of breath when I try and swallow my saliva which I constantly aspirate which leads to coughing.
    I won’t get into the social aspects of this disease, I think that they are self explanatory.
    So that is a short version of my Hx. Thanks for reading it. I’ve left out many things but if you are reading this you probably already know.
    I wish you well on your journey.
    Charles M. Schuetz MD

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