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Fatigue and insomnia, Sleep disorders

Understanding and managing insomnia in MS

Insomnia is the most common sleep disorder I encounter in my MS practice. It often goes untreated because people with MS accept it as part of living with the disease or because healthcare professionals (HCPs) prioritise other MS-related problems.

Key points

  • Insomnia is more common in people with MS than in the general population and is associated with poor mental health and other medical problems.
  • Factors that contribute to insomnia include anxiety, frequent visits to the bathroom, pain, leg spasms, restless legs, inability to roll over in bed, menopausal symptoms (hot flushes and night sweats) and poor sleep hygiene; they need to be managed appropriately.
  • Several online tools and questionnaires exist that can help you assess the nature and severity of insomnia.
  • Sleep aids (drugs) available over the counter or on prescription may be helpful.
  • Cognitive and digital approaches to insomnia management also have a role but are not widely available or suitable for everyone.
  • Complementary and alternative therapies are a valuable aid to self-management of insomnia.

Sleep, glorious sleep!

Sleep is the most essential performance-enhancing agent we know. You know what it is like if you wake in the morning and have had a good night’s sleep; you feel energised, your mood is good and you are ready to face the day. In contrast, when you wake from a night of tossing and turning, or not being able to turn, legs jerking, getting up several times to go to the toilet, maybe with a hangover from too much alcohol the night before, then you are irritable, your mood is low and it is challenging to get through the day. 

Most studies on sleep in MS show that over 70% of people with MS have a sleep disorder. In an MS-Selfie survey on sleep, a minority (33%) of 173 respondents described their sleep as good, very good or excellent, with 49% formally diagnosed with one or more sleep disorder and over 80% not having undergone formal sleep studies. Insomnia is the most common sleep disorder I encounter in my MS practice. Insomnia is defined as difficulty initiating or maintaining sleep, which can be a symptom or a disorder. If a disorder, insomnia is associated with a feeling of distress about poor sleep, and it disrupts social or occupational functioning.

Causes and impact of insomnia

In the general population, ~10% of adults have insomnia disorder and another 15 ̶ 20% report occasional insomnia, i.e. the symptom. In comparison, 40 ̶ 50% of people with MS have insomnia. Insomnia is more common in women than in men and is associated with poor mental health and other medical problems. Common MS-associated symptoms linked to insomnia (and resulting in fatigue) include pain, lack of bladder control, spasticity, restless legs, periodic limb movements and discomfort from being unable to turn in bed; other factors that contribute to insomnia – not just in people with MS but also more widely –  include alcohol and stimulant misuse, menopausal symptoms, poor sleep hygiene (daytime napping), deconditioning (lack of exercise), anxiety and depression. All these problems can interfere with sleep initiation, maintenance or perception in people with MS.

Insomnia can be episodic (with symptoms lasting 1 ̶ 3 months) or situational (of short duration, in response to a specific event of circumstance) and tends to follow a persistent course. Episodic insomnia refers to insomnia for a defined period, for example lasting several months linked to anxiety. In comparison, situational insomnia refers to insomnia triggered by a specific stimulus or event, such as sleeping away from home or after alcohol consumption. Chronic insomnia can cause depression and is associated in the general population with the development of hypertension and dementia. Insomnia assessment, diagnosis and management require a careful history to document its course, concomitant comorbidities and potential contributing factors. 

Several studies show that approximately 40% of people with MS have obstructive sleep apnoea and that it is not necessarily associated with obesity and a large neck. Sleep apnoea in MS may be due to brain stem pathology from MS affecting pharyngeal (throat) muscle function. If you know or think you are a snorer and you have periods when you stop breathing, you can download one of the many smartphone sleep apps that can assess this.

Approaches to managing insomnia

Any MS-related symptoms that can affect sleep need to be managed appropriately. How can you treat insomnia if your sleep is interrupted by anxiety-related rumination, nocturia, pain, leg spasms, restless legs, inability to roll over in bed, menopausal symptoms of hot flushes and night sweats and poor sleep hygiene? 

Recording your sleep patterns

A 24-hour history of sleep ̶ wake behaviours can help to identify additional behavioural and environmental factors for intervention. Patient-reported outcome measures (PROMS) and sleep diaries provide valuable information about the nature and severity of insomnia. They can help screen for other sleep disorders and monitor treatment progress.

A sleep diary should collect information on your sleep cycle (bedtime, arising time, napping) and estimates of your sleep ̶ wake characteristics, i.e. sleep latency (how long it takes to fall asleep), number and duration of awakenings, and an estimated overall sleep time. Useful PROMS include the Insomnia Severity Index, the Pittsburgh Sleep Quality Index, the STOP-BANG Sleep Apnea Questionnaire (for evaluating the risk of sleep apnoea) and the Restless Legs Syndrome Rating Scale. 

Sleep hygiene

I suggest you start with a simple self-help guide to improve your sleep hygiene.

  1. Ensure you spend an appropriate amount of time asleep, at least 6 hours in bed. Some people need more than this to feel refreshed. 
  2. Limit daytime naps to 30 minutes. Please note that napping does not make up for inadequate nighttime sleep. 
  3. Avoid stimulants such as caffeine, modafinil and nicotine close to bedtime. 
  4. Only drink alcohol in moderation. Alcohol is known to help you fall asleep faster, but too much disrupts sleep.
  5. Exercise helps improve sleep quality. As little as 10 minutes of aerobic exercise daily can enhance the quality of sleep. 
  6. Don’t eat before going to bed. Heavy foods and fizzy drinks can trigger indigestion or heartburn/reflux that disrupts sleep.
  7. Ensure you get adequate exposure to natural light; exposure to sunlight during the day and darkness at night help to maintain a regular sleep ̶ wake cycle. 
  8. Establish a regular relaxing bedtime routine, which helps the body recognise it is bedtime. This could include taking a shower or bath or reading. However, avoid reading or watching emotionally upsetting content before attempting to sleep.
  9. Make sure that your sleep environment is pleasant. Your mattress and pillows should be comfortable. The bedroom should be cool for optimal sleep (16 ̶ 20°C). The bright light from lamps, smartphones and television screens can make it difficult to fall asleep, so turn those lights off or adjust them when possible. Use the blue filter mode on your smartphone and other devices to reduce the inhibition of melatonin from light. Consider using blackout curtains, eyeshades, earplugs, white noise machines and other devices to make the bedroom more relaxing.
  10. If you have pain, nocturia, restless legs, sleep apnoea or other causes of discomfort, get these adequately managed via your HCP.

If these self-help measures fail, other current treatment options include prescription-only and over-the-counter (OTC) medications, cognitive behavioural therapy for insomnia (CBTI) and complementary and alternative therapies. 

Over-the-counter sleep aids

Over-the-counter sedatives tend to be first-generation antihistamines with potent centrally acting anticholinergic effects that impair cognitive function and long-term brain health. I recommend you avoid them (see newsletter entitled ‘Your anticholinergic burden’). 

Some people with MS self-medicate with OTC melatonin, cannabidiol (CBD) or tetrahydrocannabinol (THC) preparations. Melatonin has a U-shaped dose ̶ response curve for some individuals; therefore, lower doses may be better than higher doses. In general, I cannot recommend the use of CBD or THC for insomnia. CBD is a drug and is associated with liver toxicity; it may also interact with your other medications. However, if you do decide to buy CBD and/or THC, please use a reputable supplier and pharmaceutical-grade products. Medicinal cannabis cannot be prescribed on the NHS but can be obtained via private clinics. Many patients purchase it online; as a doctor, I cannot recommend buying it this way. 

Prescription-only sleep aids

If you raise the issue of insomnia with your HCP, they may reach for the prescription pad. Before accepting a sedative, please be aware of its limitations and ensure you have optimised all the above guidance. Sedatives are only a short-term solution; they work well for about 4 ̶ 5 days before you develop tachyphylaxis and need higher doses. Tachyphylaxis refers to the rapidly diminishing response to successive doses of a drug, rendering it less and less effective. Once you develop tachyphylaxis and stop taking sedatives, you may experience rebound insomnia. Benzodiazepines (e.g. diazepam) are addictive and doctors generally avoid prescribing them for insomnia. However, they still have a role when insomnia is part of acute anxiety. The sedatives most often used are the so-called Z-drugs (zolpidem, zopiclone, zaleplon and eszopiclone). Zopiclone and eszopiclone have a longer half-life than the other two drugs (5 ̶ 6 hours). In comparison, zolpidem and zaleplon act for a much shorter period (1 ̶ 3 hours). 

The older, tricyclic antidepressants, such as amitriptyline, are commonly used as sedatives. I have largely stopped prescribing them unless there is another reason for using a tricyclic, e.g. to help with pain management (please read my newsletter ‘Amitriptyline: the neurologist‘s dirty little secret’. I mostly use duloxetine in my clinical practice for pain management. It is not as sedating as tricyclic antidepressants, but some patients find it helps with sleep. Duloxetine is a serotonin ̶ noradrenaline reuptake inhibitor and has fewer anticholinergic side effects than tricyclics.

Antispasticity agents such as baclofen and gabapentinoids (gabapentin and pregabalin) also help sleep, but they should only be used for insomnia if you have spasticity or, in the case of the gabapentinoids, spasticity and/or pain that needs to be managed.  

Psychiatrists and some neurologists use sedating antipsychotics to help with insomnia. Sadly, as a neurologist, I have seen too many severe adverse events resulting from the liberal use of antipsychotics as sedatives. There needs to be a good reason for prescribing an antipsychotic, and insomnia in isolation is not one of them; however, there is a role for them in patients with cognitive issues or significant psychiatric problems. The older generation antipsychotics (e.g. haloperidol) have now been replaced by safer drugs such as quetiapine and olanzapine.

A new class of sedatives is now available in some countries; these are the dual orexin receptor antagonists suvorexant, lemborexant and daridorexant. Daridorexant is NICE approved for use by the NHS; it is recommended for treating insomnia in adults with symptoms lasting for 3 nights or more per week for at least 3 months and whose daytime functioning is considerably affected, but only if CBTI has been tried and not worked, or if CBTI is not available or is unsuitable.

Cognitive approaches to managing insomnia

Cognitive Behavioural Therapy for Insomnia (CBTI)

Only some patients receive CBTI, owing to a lack of adequately trained therapists. CBTI aims to change the behaviour and psychological factors that contribute to insomnia (e.g. anxieties and unhelpful beliefs about sleep). At the core of CBTI are behavioural and sleep-scheduling strategies (sleep restriction and stimulus control instructions), relaxation methods, psychological and/or cognitive interventions to change unhelpful beliefs or excessive worrying about insomnia, and sleep hygiene education. 

CBTI is focused on sleep and oriented toward problem-solving. A psychologist typically guides the process over roughly six consultations. Several variants in the methods for implementing CBTI include shorter formats, group therapy, using other providers such as counsellors and specialist nurses, and the use of telehealth digital platforms, including smartphone applications. 

Brief behavioural treatment for insomnia

This abbreviated version of CBTI emphasises behavioural components and is typically implemented in fewer sessions. It involves education about sleep regulation, factors that promote or interfere with sleep, and a tailored behavioural prescription based on stimulus control and sleep restriction therapy.

eCBTI

Digital CBTI (eCBTI) is becoming increasingly popular. The Sleepio application, which is recommended and covered by the NHS, has a positive effect on several sleep outcomes and is said to be as effective as medication. NICE recommends Sleepio as a cost-saving option for treating insomnia and insomnia symptoms in primary care for people who would otherwise be offered sleep hygiene or sleeping pills. A medical assessment should be done before referral to Sleepio for people who may be at higher risk of other sleep disorder conditions, such as during pregnancy or in people with comorbidities.

Complementary and alternative therapies

Sleep restriction

Limit the time you spend in bed to match your sleep time as closely as possible. After the initial restriction, the sleep window can be gradually adjusted upward or downward on a weekly basis as a function of sleep efficiency (time asleep÷time spent in bed×100) until an appropriate sleep duration is established.

Stimulus control

You need to follow a set of instructions designed to reinforce the association between bedtime and bedroom stimuli with sleep and to re-establish a consistent sleep ̶ wake schedule.

  • Go to bed only when you feel sleepy.
  • Get out of bed when you are unable to sleep.
  • Use the bed and bedroom for sleep and sex only; do not use your bed for reading, watching television, etc.
  • Try and get up at the same time every morning.
  • Avoid napping.

Relaxation training

Try using different procedures such as progressive muscle relaxation and imagery training to reduce arousal, muscle tension and intrusive thoughts that interfere with sleep. Relaxation procedures need to be practised daily over a few weeks. 

Cognitive therapy

This is a psychological approach to revising many common misconceptions about sleep and reframing unhelpful beliefs about insomnia and its daytime consequences. This method also reduces excessive worrying about sleep difficulties and their daytime consequences. Additional cognitive strategies include paradoxical intention (willingly trying to stay awake rather than trying to fall asleep) to alleviate the performance anxiety triggered by attempting to force sleep.

Sleep hygiene education

These general guidelines include advice about a healthy diet, exercise, substance use, and optimising environmental factors such as light level, noise and excessive temperature that may promote or interfere with sleep (see above). 

Acceptance and commitment therapy (ACT)

ACT is a form of psychotherapy that aims to educate people to stay focused on the present moment and accept life experiences, thoughts, and feelings (even negative ones) without trying to change them. ACT uses different methods and processes (e.g. acceptance, defusion, mindfulness, and committed action) to increase psychological flexibility.

Mindfulness

This meditation method involves observing one’s thoughts and feelings and letting go of the need to change or ruminate. Originally designed to reduce stress and anxiety, mindfulness has been adapted for the management of insomnia and can be included as one component of ACT.

Conclusion

Poor sleep, be it due to a comorbid sleep disorder, MS-related symptoms or poor sleep hygiene, is a very common problem in people with MS. It contributes to daytime fatigue and hypersomnolence and impacts physical and cognitive function. As a result, poor sleep reduces quality of life and can exacerbate other MS-related problems such as poor cognition, anxiety and depression. It is essential that poor sleep is documented, investigated appropriately and treated accordingly to improve the functioning and quality of life of people with MS.

Fatigue and insomnia, Sleep disorders

Fatigue in MS – a disabling symptom

Fatigue in MS is common, but it is often not investigated or managed properly. This post highlights the complexity of MS-related fatigue and explains why and how to manage it holistically. 

Key points

  • The different mechanisms underlying MS-related fatigue are explained.
  • The MS disease process, the burden of living with MS, and other factors such as drug side effects, comorbidities and lifestyle choices may all contribute to fatigue in MS.
  • Practical guidance is provided on managing many aspects of MS-related fatigue, using a holistic and systematic approach.
  • Not all fatigue is MS-related; it is important to ascertain if your fatigue could be due to another disease process.

Fatigue is one of the most disabling of all the symptoms of MS. It is the symptom that over 50% of people with MS would most like to be rid of. MS-related fatigue has several underlying mechanisms.

Fatigue caused by MS disease processes

Inflammation in the brain

Inflammatory mediators or cytokines associated with MS – in particular, interleukin-1 (IL-1) and TNF-alpha – trigger ‘sickness behaviour’. This is the response to inflammation that forces us to rest and sleep so that our body can recover. Sickness behaviour is also the body’s response to a viral infection such as flu; in fact, many people with MS describe their fatigue as being like the fatigue they experience with flu. 

Sickness behaviour from an evolutionary perspective is well conserved and occurs in most animals. This type of fatigue needs to be managed by switching off ongoing inflammation in the brain. Many people with MS who take a highly effective DMT report feeling much better and free from fatigue and/or brain fog. This is why recent-onset fatigue that cannot be explained by other factors (see below) may indicate MS disease activity. At present, fatigue on its own does not constitute a relapse.

Many patients with MS who have had COVID-19 tell me that MS-related cog-fog and fatigue feel like the cog-fog and fatigue of COVID-19 and long-COVID. As many as one in four people with long-COVID experience cog-fog, which includes problems in attention, language fluency, processing speed, executive function, and memory: these are the same problems that affect people with MS. 

Cog-fog related to MS and to COVID-19 could be linked to the same inflammatory mechanisms. This syndrome of systemic inflammation causing profound fatigue and cog-fog is not new. Some people with MS who have a systemic infection take weeks or months to return to normal; some patients with more advanced MS never return to their original baseline. This is why, as part of the holistic management of MS, we need to treat and prevent systemic infections as best we can.

The overlap between COVID-19 and MS-related cog-fog raises the question whether both are due to viral infections. There is some evidence of recent Epstein-Barr virus (EBV) reactivation in patients with long-COVID,1 suggesting that the EBV rather than the SARS-CoV-2 may be causing long-COVID symptoms. This is important because chronic EBV infection has been associated with chronic fatigue syndrome. It has also been suggested that chemo-brain is due to similar mechanisms, i.e. chemotherapy triggers CNS inflammation, which causes cog-fog.

Neural plasticity

When parts of the brain are damaged by MS, other areas are co-opted to help take over, or supplement, the function of the damaged area. In other words, people with MS use more brain power than people without MS to complete the same task. This usually manifests as mental fatigue and is why people with MS have difficulty concentrating for prolonged periods and multitasking. At present we have no specific treatment for this type of fatigue, but some patients find amantadine or modafinil helpful. There is also some emerging evidence that fampridine may help with cognitive fatigue. However, preventing damage in the first place should prevent this type of fatigue.

Exercise-related conduction block

Damage to axons that conduct electrical impulses is the reason why people with MS notice their legs getting weaker or another neurological symptom getting worse with exercise. We think this is due to demyelinated or remyelinated axons failing to conduct electrical impulses when they become exhausted. Exercise-induced fatigue is probably the same as temperature-related fatigue; a rise in body temperature also causes vulnerable axons to block and stop conducting. To deal with this type of fatigue we need therapies to promote remyelination and to increase conduction. These types of fatigue are treated by rest, cooling and possibly drugs such as fampridine that improve conduction. At the heart of this type of fatigue is localised energy failure.

Fatigue from living with MS symptoms

Temperature sensitivity

Many people with MS are temperature sensitive. Typically, high temperatures worsen fatigue, but low temperatures also affect some patients. Many people with MS manipulate their behaviour to avoid hot or cold environments. Some find it helpful to use cooling suits, but these are costly and are not covered by NHS funding. Cold or ice baths, swimming and air conditioning can all help with temperature-related fatigue.

Case example

One of my patients had a walk-in butcher’s fridge installed in her house, and she spends 30 minutes there 4 ̶ 5 times a day to manage her fatigue. She is a wheelchair user, and she sits in her wheelchair in the fridge.

Menstrual and menopausal fatigue

Menstrual (or catamenial) fatigue is a form of temperature-related fatigue that occurs in women during the second half of the menstrual cycle when their body temperature increases. It responds to paracetamol and to non-steroidal anti-inflammatory drugs such as ibuprofen and naproxen. Fatigue is a common symptom of menopause too; some women with MS who are menopausal and have fatigue find hormone replacement therapy helpful. 

Whether or not men go through a ‘menopause’ is a moot point. Testosterone levels do drop with age, however, and some male patients find that testosterone replacement therapy helps their MS-related fatigue. In the UK, the indications for testosterone replacement therapy are very well defined and do not include MS-related fatigue, so most people with MS who want to try this therapy need to pay for a private prescription.

Bladder problems

Intermittent waking due to bladder problems may result in fatigue from disrupted sleep. Bladder problems may also contribute to insomnia, with the affected individual needing to visit the bathroom frequently and unable to relax into sleep. For detailed guidance on managing bladder problems, particularly at night, please see the bladder and bowel section of the website, particularly the article on nocturia.  

Insomnia due to pain and discomfort

Other disease-related factors that contribute to fatigue include insomnia from pain, discomfort of being unable to turn in bed and restless legs syndrome (RLS). RLS is common in people with MS, affects sleep quality and is associated with poor cognition. For detailed guidance on managing these MS symptoms, please see the post entitled Sleep disrupted by pain and discomfort.  

A case scenario

“A 28-year-old woman with early relapsing ̶ remitting MS, on glatiramer acetate, and little overt neurological impairment suffers from severe fatigue, which is worse during the latter half of her menstrual cycle. She has recently split up with her long-term partner because of the impact her symptoms have had on her relationship. She has also had to stop working as a bank clerk because of her fatigue.”

Prof G’s response
This patient needs to be examined and will need an MRI and a lumbar puncture to measure her spinal fluid neurofilament levels. If she has evident inflammatory disease activity, her DMT will need to be switched. She needs a full medical assessment, which includes a screen for comorbidities.

The patient complains of cognitive fatigue and, despite not having much physical disability, she was found to have a high brain MS lesion load and noticeable brain volume loss. A formal neuropsychological assessment to establish if she has cognitive impairment would allow her to be referred to a cognitive rehabilitation programme; this can target specific areas to help her cope with her cognitive deficits.

To combat fatigue during her menstrual cycle, this patient did well on naproxen, which is longer acting than ibuprofen and paracetamol. Naproxen only needs to be taken during the second half of her cycle. She was screened for poor sleep hygiene, and she volunteered intermittent early morning waking due to bladder problems and anxiety. Both would need to be addressed as part of her fatigue management programme.

It was clear that the patient had both depression and anxiety, which were related to the impact of MS on her occupational and social functioning. This must be managed with cognitive behavioural therapy (CBT), mindfulness and an exercise programme. If this approach is not helpful, then I would suggest the judicious use of an antidepressant and, failing this, a referral to a psychiatrist and/or psychologist.

Fatigue resulting from other factors

Comorbidities and other diseases

Comorbidities and other diseases related to MS can cause fatigue and should be screened for. These include infections (see above). In people with more advanced MS, the urinary tract is most often affected, but other sites of infection include the sinuses, teeth, lungs, skin (intertrigo and pressure sores) and bowels.

Fatigue is common with thyroid disease; an underactive thyroid gland (hypothyroidism) and an overactive gland (hyperthyroidism, or thyrotoxicosis) cause fatigue. Diabetes, other endocrine (hormonal) problems, anaemia and heart, kidney, liver or lung diseases all cause fatigue.

Side effects of drugs

Fatigue is a common side effect of many medications, particularly drugs that cause sedation and some DMTs. Flu-like side effects from interferon-beta, for example, may make fatigue worse. Anticholinergics and antispasticity drugs are sedating, blunt cognition and may worsen MS-related fatigue. If you have fatigue, therefore, it is important to review your medications. MS is associated with polypharmacy, but some of the medications that cause or exacerbate fatigue can be reduced in dose, stopped or potentially replaced with alternatives that don’t exacerbate fatigue.

Lack of sleep and/or sleep disorders

Poor sleep means you feel tired in the morning. Most people with MS have poor sleep hygiene and almost half have an actual sleep disorder. A clue to this is how you feel in the morning and whether you have excessive daytime sleepiness. If you wake up in the morning and don’t feel refreshed and/or you fall asleep frequently during the day, you need a formal sleep assessment. You can complete the Epworth Sleepiness Scale online to see if you have a problem.

Depression and anxiety

Fatigue is a common symptom of depression and anxiety. Of the many online screening tools for depression and anxiety, the best one to use if you have MS is probably the Hospital Anxiety and Depression Scale (HADS). 

Obesity

Being overweight requires additional energy to perform physical tasks, and obesity itself causes fatigue. Recently an association has been found between obesity and depression. Obesity also predisposes you to sleep disorders; obese people with MS are more likely to have obstructive sleep apnoea. For all these reasons you should engage with lifestyle and wellness programmes to manage obesity and fatigue. 

Deconditioning

Deconditioning is simply the term we use for being unfit. If you are unfit, performing a demanding physical task makes you tired. Deconditioning is treated with exercise, which paradoxically can reduce fatigue. Patients may claim that exercising makes their fatigue worse. Yes, that does happen, but if you persevere and get fitter your fatigue often improves. The important thing is to start a graded exercise programme and build up slowly. Exercise does some incredible things to the brain, many of which explain why it is effective at treating not only fatigue but also depression and anxiety. Exercise is a form of ‘disease-modifying therapy’ and hence everyone with MS should be participating in an exercise programme. 

Poor nutrition and ‘food coma’

Some people with MS are anorexic and eat very poorly; as a result, they have little energy. Although this is quite rare, I have had a few such patients over the years. Similarly, overnutrition may have the same effect. Some of the hormones your gut produces cause you to feel tired and want to sleep; this is the so-called siesta effect (also referred to as food coma or postprandial hypersomnolence). Reducing the size of your meals and changing your eating behaviour may improve this. Postprandial hypersomnolence has two components.

  1. A state of perceived low energy related to activation of the parasympathetic nervous system (which is part of the autonomic nervous system) in response to expansion of the stomach and duodenum from a meal. In general, the parasympathetic nervous system slows everything down. 
  2. A specific state of sleepiness triggered by the hormone cholecystokinin that helps digest food and regulate appetite. It is released in response to eating and to changes in the firing and activation of specific brain regions. The coupling, or interaction, of digestion and the brain is referred to as ‘neurohormonal modulation of sleep’ and it underlies the reflexes responsible for postprandial hypersomnolence. There is therefore a well-studied biological reason why we feel sleepy after eating a meal. 

Managing food coma – practical tips

The first patient who alerted me to the problem of food coma in MS was so affected by postprandial hypersomnolence that she now eats only one meal a day, late in the evening. She can then ‘crash’ and go to sleep about an hour after eating. She needs to be functional during the day but cannot do her professional work if she eats anything substantial during working hours because of her overwhelming desire to sleep. She has tried caffeine, modafinil and amantadine to counteract postprandial hypersomnolence, but all these substances had only a small effect.

Other patients reporting postprandial hypersomnolence derive some benefit from the judicious use of stimulants. You can start by self-medicating with caffeine, but this may have the drawback of worsening your bladder function. Please note, however, that it is not advisable to take stimulants later than about 3 pm or 4 pm because they have a long half-life and can cause insomnia.

Some patients find carbohydrate-rich foods particularly potent at inducing ‘food coma’. Indeed, glucose-induced insulin secretion is one of the drivers of this behavioural response. This may be why people who fast or eat very low-carbohydrate or ketogenic diets describe heightened alertness and an ability to concentrate for long periods. Another option is to reduce your meal size: instead of large meals, try eating multiple small snacks during the day.

Exercise has helped some patients deal with postprandial hypersomnolence. I am not sure exactly how exercise works – possibly by lowering glucose and insulin levels and improving insulin sensitivity. The latter will reduce hyperinsulinaemia, which not only causes postprandial hypersomnolence but is an important driver and component of metabolic syndrome and obesity.

Postprandial hypersomnolence will be worse if you already suffer from a sleep disorder and excessive daytime sleepiness. Most people with MS have a sleep disorder, so there is little point in focusing on postprandial hypersomnolence and ignoring the elephant in the room.

Using your energy effectively

One strategy to manage MS-related fatigue is to imagine your energy levels as a battery, i.e. you have only so much energy in the day. People with MS have smaller batteries than people without MS and therefore need to plan their day and activities to maximise their use of energy. For example, if you do something tiring in the morning, you should rest in the afternoon to conserve energy for evening activities. Similarly, if you find some activities very tiring, such as taking a hot shower or bath, plan to do this in the evening before bed.

Conclusion

It is apparent from this discussion that fatigue in MS is more complex than we realise. So be careful, or at least wary, if your neurologist simply wants to reach for the prescription pad to get you out of the consultation room. Any MS-related symptoms that can affect sleep need to be managed accordingly. Like other MS-related problems, a holistic and systematic approach is needed to manage and treat MS-related fatigue correctly. Not all fatigue is MS-related. This is why it is important to take a step backwards and ask yourself if your fatigue could be due to another disease process.

Reference

  1. Gold JE et al. Investigation of long COVID prevalence and its relationship to Epstein-Barr virus reactivation. Pathogens 2021;10:763.