Living with NDM

If you have been diagnosed with NDM, it is common to question how it might affect your life. Below you can find answers to some of the more common questions that people with NDM have. However, as every person’s experience with NDM varies, you should speak to your healthcare team about your own individual case.

Sometimes people with NDM find it difficult to stand up from a chair. This can be embarrassing in work or social situations and they often need to warm up their muscles first.1

How might NDM affect my day-to-day life?

The symptoms and severity of NDM vary from one person to another. For some people with NDM, some aspects of daily life may be challenging, however there are ways to help you manage your symptoms.

Key symptoms of NDM are muscle stiffness (often described as muscle “locking up”) or cramps, weakness, fatigue and pain.2,3 For most people, these symptoms present in the arms and legs, which can cause problems with some activities like using stairs and running, or may increase the risk of falls and change the way you walk.2,3 Less commonly, NDM affects facial muscles leading to problems with chewing, eyelid myotonia, blurred vision or a squint.

How NDM may affect your day-to-day life depends on the type of NDM you have, with some forms like potassium-sensitive myotonias that would require dietary restrictions (e.g. reducing potassium rich food), or paramyotonia congenita that would require avoiding cold temperatures or extensive
exercise.4

Can I still play sports?

Exercise and activity are important to maintain a healthy lifestyle.4 However, cold and/or sudden forceful contractions can trigger your muscles to lock up, so it is important to find ways to remain active without provoking NDM symptoms. You can find more tips on exercise here.

You may need to adopt different strategies for exercise depending on the type of NDM you have; for instance, myotonia congenita will require you to warm up your muscles, whereas paramyotonia congenita may get worse as you exercise and you may need to take more breaks.

Patients who find that myotonia is painful for them or who experience fatigue, may find it more difficult to be active5 and should seek advice from their healthcare team.

Will my symptoms get worse?

Although NDM is often thought of as a “mild” condition, some patients have reported that their symptoms get worse over time.5 Speak to your healthcare team about worsening symptoms if they impact your quality of life, they may have additional management strategies that you can try.

Will NDM affect any other aspects of my health and well-being?

The impact of NDM on everyday life can lead some people to feel unhappy, worried or anxious when they are out of the house. Some people may feel that their quality of life is being affected.3 These negative emotions and concerns are normal consequences of having a condition such as NDM, and it is ok to feel this way. Don’t be afraid to talk to friends, family or a member of your healthcare team about how you are feeling. You might also find it useful to get in touch with other people who are living with NDM and other rare diseases who will share some of your experiences.

Will I pass NDM on to my children?

NDM is caused by a mutation in a gene, which prevents muscles from relaxing normally.6,7 NDM is inherited, however the ways in which it is passed on depends on the type of NDM that you have.

Learn more about how NDM can be inherited.

Can NDM be treated?

Some people with NDM manage their symptoms by adapting the way they do things. However, if your symptoms continue to affect your daily life, you may wish to seek further advice from your doctor about other ways to clinically manage your condition.

There is currently no cure for NDM, but you can learn more about improving the management of NDM symptoms and how to find specialist healthcare advice.

References
  • Diaz-Manera J. EMJ. 2021;6[2]:37-46
  • Stunnenberg BC, et al. Muscle Nerve 2020;62:430-444
  • Trip J, et al. J Neurol Neurosurg Psychiatry 2009;80:647-652
  • Jitipolmard N, et al. Curr Treat Options Neurol 2020;22:34
  • Trip J, et al. J Neurol 2009;256:939–947
  • Hahn C, Salajegheh MK. Iran J Neurol 2016;15:46–53
  • Vereb N. J Neurol. 2021; 268(5): 1708–1720

UK-NDM-2202-00010 February 2022

Foods to avoid on a low-potassium diet*

  • Fruit1,2
  • Vegetables1,2
  • Beans/legumes1,3
  • Other1-3
  • Avocado
  • Artichoke
  • Baked beans
  • Bran cereal
  • Apricots
  • Beetroot
  • Kidney beans
  • Dairy (eg yoghurt, milk)
  • Bananas
  • Brussel sprouts
  • Lentils
  • Nuts
  • Dried fruits eg dates, raisins and prunes
  • Broccoli (cooked)
  • Brown rice
  • Grapefruit
  • Okra
  • Salt substitutes
  • Kiwi
  • Parsnip
  • Wholewheat bread and pasta
  • Mango
  • Potatoes (processed or with skin on)
  • Melons
  • Cooked spinach
  • Nectarines
  • Tomato (concentrated, eg. Tomato puree)
  • Oranges and orange juice
  • Papaya
  • Pomegranate and pomegranate juice
  • Fruit1,2

    Avocado

    Apricots

    Bananas

    Dried fruits eg dates, raisins and prunes

    Grapefruit

    Kiwi

    Mango

    Melons

    Nectarines

    Oranges and orange juice

    Papaya

    Pomegranate and pomegranate juice

  • Vegetables1,2

    Artichoke

    Beetroot

    Brussel sprouts

    Broccoli (cooked)

    Okra

    Parsnip

    Potatoes (processed or with skin on)

    Cooked spinach

    Tomato (concentrated, eg. Tomato puree)

  • Beans/legumes1,3

    Baked beans

    Kidney beans

    Lentils

  • Other1-3

    Bran cereal

    Dairy (eg yoghurt, milk)

    Nuts

    Brown rice

    Salt substitutes

    Wholewheat bread and pasta

*Meat and fish contain a moderate amount of potassium but they are an important source of protein so shouldn’t be avoided; Dairy products contain potassium but are an important source of calcium so should be consumed in moderation
References
  • WebMD. Low-potassium diet: what to know? Available at: https://www.webmd.com/food-recipes/low-potassium-diet-foods ; Accessed February 2022
  • St Georges Kidney Patients Association. Eating on a low potassium diet. Available at: https://www.sgkpa.org.uk/main/eating-well-on-a-low-potassium-diet-2 ; Accessed February 2022
  • NHS. Information for people on a low potassium diet. Available at: https://www.nth.nhs.uk/content/uploads/2019/02/PIL1061-Information-for-people-following-a-low-potassium-diet-Final-11.02.19-LP.pdf ; Accessed February 2022
  • NDM type1
  • Symptoms2,3
  • Which type of ion channel? 2,3
  • How is it inherited?2,3
  • Thomsen myotonia congenita

    (also called Thomsen myotonia or autosomal dominant myotonia congenita)
  • Lower limbs tend to be more affected, although can also affect the arms, hands and face. Stiffness may be worse when you first try to move after a period of inactivity, and may ease as you ‘warm up’.
  • Chloride (Cl-)
  • Autosomal dominant
  • Becker myotonia congenita

    (also called Becker myotonia, Becker disease, generalized myotonia, recessive generalized myotonia or autosomal recessive myotonia congenita
  • Lower limbs tend to be more affected, although can also affect the arms, hands and face. Stiffness may be worse when you first try to move after a period of inactivity, or if you are startled, and may ease as you ‘warm up’. Sometimes people with Becker myotonia congenita experience temporary weakness after an episode of myotonia.
  • Chloride (Cl-)
  • Autosomal recessive
  • Paramyotonia congenita

    (Also called Eulenburg disease, paralysis periodica paramyotonia, paramyotonia congenita of von Eulenburg, PMC or von Eulenburg’s disease)
  • Myotonia mainly affects hands and face and gets worse with exercise. Cold is also a key trigger of myotonia, and muscle weakness after an episode of myotonia may last hours or sometimes days.
  • Sodium (Na+)
  • Autosomal dominant
  • Sodium channel myotonia, SCM:

    myotonia permanens and myotonia fluctuans, acetazolamide-responsive myotonia (ARM) previously known as Potassium aggravated myotonias (PAM)
  • Potassium-aggravated myotonia is a rare form of NDM that affects all areas of the body. Myotonia attacks are triggered by eating potassium-rich foods. Symptoms may fluctuate widely from day to day (myotonia fluctuans) or are constant and severe (myotonia permanens).
  • Sodium (Na+)
  • Autosomal dominant
  • Other closely related sodium disorders with myotonia

    (including hyperkalemic paralysis or hyperPP)
  • Myotonia is usually mild, and often involves the eyelids, hands, and tongue. Attacks of weakness can occur at any time and are commonly triggered by rest following exercise, fasting, eating potassium-rich foods or stress.
  • Sodium (Na+)
  • Autosomal dominant
References
  • Stunnenberg B. Muscle Nerve. 2020 Oct; 62(4): 430–444
  • Hahn C, Salajegheh MK. Iran J Neurol 2016;15:46–53
  • Matthews E, et al. Brain 2010:133; 9–22
  • NDM type1

    Thomsen myotonia congenita

    (also called Thomsen myotonia or autosomal dominant myotonia congenita)

    Becker myotonia congenita

    (also called Becker myotonia, Becker disease, generalized myotonia, recessive generalized myotonia or autosomal recessive myotonia congenita

    Paramyotonia congenita

    (Also called Eulenburg disease, paralysis periodica paramyotonia, paramyotonia congenita of von Eulenburg, PMC or von Eulenburg’s disease)

    Sodium channel myotonia, SCM:

    myotonia permanens and myotonia fluctuans, acetazolamide-responsive myotonia (ARM) previously known as Potassium aggravated myotonias (PAM)

    Other closely related sodium disorders with myotonia

    (including hyperkalemic paralysis or hyperPP)

  • Symptoms2,3

    Lower limbs tend to be more affected, although can also affect the arms, hands and face. Stiffness may be worse when you first try to move after a period of inactivity, and may ease as you ‘warm up’.

    Lower limbs tend to be more affected, although can also affect the arms, hands and face. Stiffness may be worse when you first try to move after a period of inactivity, or if you are startled, and may ease as you ‘warm up’. Sometimes people with Becker myotonia congenita experience temporary weakness after an episode of myotonia.

    Myotonia mainly affects hands and face and gets worse with exercise. Cold is also a key trigger of myotonia, and muscle weakness after an episode of myotonia may last hours or sometimes days.

    Potassium-aggravated myotonia is a rare form of NDM that affects all areas of the body. Myotonia attacks are triggered by eating potassium-rich foods. Symptoms may fluctuate widely from day to day (myotonia fluctuans) or are constant and severe (myotonia permanens).

    Myotonia is usually mild, and often involves the eyelids, hands, and tongue. Attacks of weakness can occur at any time and are commonly triggered by rest following exercise, fasting, eating potassium-rich foods or stress.

  • Which type of ion channel? 2,3

    Chloride (Cl-)

    Chloride (Cl-)

    Sodium (Na+)

    Sodium (Na+)

    Sodium (Na+)

  • How is it inherited?2,3

    Autosomal dominant

    Autosomal recessive

    Autosomal dominant

    Autosomal dominant

    Autosomal dominant

References
  • Stunnenberg B. Muscle Nerve. 2020 Oct; 62(4): 430–444
  • Hahn C, Salajegheh MK. Iran J Neurol 2016;15:46–53
  • Matthews E, et al. Brain 2010:133; 9–22