Everything You Want to Know About Brain Fog on Dialysis

On dialysis, you may have a hard time thinking clearly, a problem some call “brain fog.” Here is what some people say about brain fog and how it feels:

What Should I Know About Brain Fog?

As you just saw in the quotes, “brain fog” or “kidney brain” may include poor:

Researchers use a number of terms to cover what you might call brain fog.

Cognitive function includes how well you can:

Executive function includes how well you can:

These problems can be worse if you have diabetes or heart and blood vessel disease.1 A clear head and being able to follow steps are key to sticking with your treatment plan. Studies find that on dialysis, you are more likely to have problems with how well you can think. This risk can affect how well you feel and do. But, there is no national screening for cognitive issues on dialysis.

Who is at Risk?

Studies have found that those on standard HD in a clinic have higher rates of brain fog than the general public. The risk goes up for those who are older,2 black, female or live in a nursing home.3 Mental status changes may lead to depression4—or vice versa.5 No one knows which comes first.

Other Causes of Brain Fog

A number of issues can affect how well you think. Talk with your doctor if you have any of these:6,7

Are You Worried About Dementia?

When you forget things or lose words, you might worry that something more serious is wrong. The Mini-Cog screening tool takes 3 minutes or so and can tell you if you are at risk for dementia. If you want to try it, you’ll need a helper. Follow the steps in this table.

Helper Tasks Your Tasks
  1. Say any three words to you.

Repeat the words.
  1. Give you a sheet of paper and a pencil. Time you for 3 minutes.

  • Draw a round clock face.

  • Put the numbers around it in the right places.

  • Draw the hands at 11:10

  1. Ask you to repeat the three words from before.

Repeat the words.


  • You get one point for each of the three words you recall in step 3.

  • You get 2 points for a clock face that is round and has the numbers and hands in the right places.

  • A score of 3 or more means that you may have a low risk of dementia.8 You can still have “brain fog” or “kidney brain.” If you score less than 3, talk with your doctor.

Tips for Easing Brain Fog

There may be things you can do to think more clearly, such as:


Brain fog affects your quality of life, and can affect how well you take care of yourself. If you have brain fog, tell your doctor and care team. Ask them if your health, dialysis, or medicines you take could make it worse, and what can treat it. Knowing more will help you to get the help you need to think more clearly and live better.


    1. Drew DA, Weiner DE, Tighiouart H, et al. Cognitive Decline and Its Risk Factors in Prevalent Hemodialysis Patients. Am J Kidney Dis. 2017 Jun;69(6):780-787. https://www.ncbi.nlm.nih.gov/pubmed/28131531

    2. O’Lone E, Connors M, Masson P, et al. Cognition in people with end-stage kidney disease treated with hemodialysis: A systematic review and meta-analysis. Am J Kidney Dis. 67(6):925–35. https://www.ncbi.nlm.nih.gov/pubmed/26919914/

    3. McAdams-DeMarco MA, Daubresse M, Bae S, et al. Dementia, Alzheimer’s Disease, and Mortality after Hemodialysis Initiation. Clin J Am Soc Nephrol. 2018 Aug 9. [Epub ahead of print]. https://www.ncbi.nlm.nih.gov/pubmed/30093374

    4. Jung S, Lee YK, Choi SR, et al. Relationship between cognitive impairment and depression in dialysis patients. Yonsei Med J, 54 (2013), pp. 1447-1453.

    5. Dong J, Pi HC, Xiong ZY, et al. Depression and cognitive impairment in peritoneal dialysis: A multicenter cross-sectional study. Am J Kidney Dis. 2016 Jan;67(1):111-8. https://www.ncbi.nlm.nih.gov/pubmed/26255306

    6. Reasons you may have brain fog. https://www.webmd.com/brain/ss/slideshow-brain-fog

    7. 6 Possible causes of brain fog. https://www.healthline.com/health/brain-fog#causes

    8. Mini-Cog screening for older adults: Using the Mini-Cog. https://mini-cog.com/about/using-the-mini-cog/

    9. Vitamin B12: What to Know. https://www.webmd.com/diet/vitamin-b12-deficiency-symptoms-causes

    10. Campbell B. Lifting the fog: Treating cognitive problems. http://www.cfidsselfhelp.org/library/lifting-fog-treating-cognitive-problems

    11. Xie L, Kang H, Xu Q, Chen MJ, Liao Y, Thiyagarajan M, O’Donnell J, Christensen DJ, Nicholson C, Iliff JJ, Takano T, Deane R, Nedergaard M. Sleep drives metabolite clearance from the adult brain. Science. 2013 Oct 18;342(6156):1-11