aHUS and Sleep Disorders

Patients with atypical hemolytic uremic syndrome (aHUS) may experience problems with sleep. Here are some ways that aHUS can lead to sleep disorders and possible treatment options.

What is aHUS?

aHUS is a disease where the immune system is overactive, causing damage to blood vessels and leading to the formation of blood clots in small blood vessels. These blood clots, called thrombotic microangiopathy (TMA), cause a loss of oxygen and nutrients to different organs in the body, especially the kidneys. The blockages can also lead to anemia due to red blood cells rupturing as they attempt to squeeze past the blockages. The body’s platelets play a role in the formation of these small clots, so there are lower levels in the blood. This causes patients to have a higher risk of bleeding and bruising.

What are sleep disorders?

Researchers estimate that 50 million to 70 million Americans have some form of sleep disorder. These are defined as any issues that interfere with normal sleep patterns. They include difficulties falling asleep (insomnia), problems getting restful sleep, sleep apnea, and falling asleep during the day.

What are the risks associated with sleep disorders?

Lack of sleep can impact a person’s health, ability to function, and quality of life, and increase their irritability and stress. Finally, it can be a significant risk factor for cardiovascular disease.

How could aHUS cause sleep disorders?

One of the primary symptoms of aHUS is kidney damage related to TMA. This can lead to chronic kidney disease (CKD). Although no studies have investigated sleep disturbances in aHUS patients specifically, numerous studies have shown that patients with CKD experience sleep disorders. Some of the most common include sleep-disordered breathing such as sleep apnea, restless leg syndrome, periodic limb movement disorder, and excessive daytime sleepiness.

Researchers think that sleep-disordered breathing in CKD patients is related to the retention of too much fluid and toxins causing issues with the control of breathing and causing the airways to narrow.

Anemia, low iron, and nervous system abnormalities could lead to restless leg syndrome and periodic limb disorders in CKD patients. TMA in patients with aHUS can cause issues with the nervous system due to decreased blood supplies to nerve cells and could contribute to nervous system abnormalities.

Other sleep disorders affecting patients and interfering with their ability to get a good night’s rest often causes excessive daytime sleepiness.

How common are sleep disorders in aHUS?

Researchers don’t know the exact prevalence of sleep disorders in aHUS. However, they estimate sleep-disordered breathing to be between 50% and 70% in patients with CKD. They detected sleep disturbances in 75.9% of children with CKD — 22% of these being excessive daytime sleepiness and 20.4% being restless leg syndrome.

How do doctors treat sleep disorders?

Several of the sleep disturbances in CKD may be related to increased fluid levels and excess toxins in the blood. A study found that patients on dialysis experienced improvements in their sleep apnea when they underwent nocturnal hemodialysis. Nocturnal hemodialysis involves patients undergoing hemodialysis while they sleep. It results in improved clearance of waste and fluids.

A case study of a child with aHUS indicated improvement of symptoms, including a more normal sleep schedule, after the patient was put on eculizumab. This suggests that the treatment may also help with sleep.

Patients should check with their physicians if other treatments could help with sleep disturbances. Doctors may recommend medication to help patients fall asleep or stay asleep for longer, or tools such as continuous positive airway pressure machines to help with sleep apnea.

Last updated: Nov. 2, 2020

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aHUS News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.