Learn some medical conditions that can interfere with memory and thinking.

Medical conditions can interfere with memory and the ability to process information. Sometimes, treating health problems alone will improve memory. If you suspect that you are having memory difficulties, talk to your doctor about what’s going on. Here is a list of some of the health conditions that can cause problems with cognition.     

Depression

Depression can cause problems with learning, attention, concentration, and memory. In fact, depression and cognitive decline often occur together.

• A person is more likely to be suffering from depression than dementia if they have:
• A history of psychiatric illness
• Sudden onset of memory and thinking problems
• Trouble sleeping
• Rapid decline in the ability to perform everyday activities
• Depression and dementia can be hard to tell apart. A doctor may use a trial of antidepressant medicine to make the distinction. Improvement after 6 or 8 weeks suggests depression.
• When they are tangled together, treating the depression does not reverse the dementia.¹

Heart failure

Heart failure is an inability of the heart to pump blood to reach every part of the body and lungs. A 2017 systematic review confirmed that heart failure is associated with cognitive impairment. Whether it causes cognitive impairment is not yet known.²

Coronary bypass surgery

A 2019 systematic review confirmed that coronary bypass surgery can affect memory. 

• About 43% of patients who underwent bypass surgery had postoperative cognitive decline. 
• After initial resolution in some patients, the percentage climbed back up to about 40% after 1 to 5 years.³
• The heart-lung machines used during the surgery seemed to be responsible. But newer “off-pump” procedures fail to lessen the risk.⁴

Obstructive sleep apnea

Some research suggests that obstructive sleep apnea (OSA) can affect cognition.⁵ The findings have been mixed.

• A 2017 systematic review showed a 26% higher risk of decline in executive functioning but not in memory.⁶
• A 2020 review showed that OSA correlated with cerebral small-blood-vessel disease. That suggested a possible mechanism for cognitive decline.⁷
• A 2020 study showed that beta-amyloid plaque, a hallmark of Alzheimer’s disease, was increased in the brains of patients with severe OSA.⁸

Other medical problems

Other medical conditions that can lead to memory problems include:

• Hormonal abnormalities
• Thyroid disease (hypothyroidism or hyperthyroidism)
• Cushing’s syndrome (excessive corticosteroids)
• Hypertension
• There’s good evidence that people with chronic high blood pressure are more likely to suffer cognitive decline.
• Those with increased arterial stiffness are at higher risk.⁹
• But proving that lowering blood pressure reduces the risk of cognitive decline has turned out to be difficult.
• Strokes
• Hearing or vision loss^10,11  
• Dietary deficiencies
• Supplements of omega-3 fatty acids, vitamins B6, B12, D, A, C, E, and folate have been associated with a decreased risk of dementia.¹²
• Stress and anxiety¹³
• Fever
• Viral infections, such as COVID-19, HIV/AIDS, Zika, and viral encephalitis
• Bacterial infections, such as Lyme disease and syphilis
• Drug treatments (for many disorders)
• Direct brain injury:
• Primary brain tumor or cancer that has spread to the brain
• Traumatic brain injury
• Car accident or other source of closed head trauma
• Repeated blows to the head, from sports (soccer, football, boxing), falls, or work
• Subdural hematoma (collection of blood between the skull and the brain), often related to anticoagulant use¹⁴
• Normal pressure hydrocephalus (excess fluid in the brain)¹⁵  
• Long-term heavy use of alcohol:¹⁶
• Commonly implicated in serious cognitive decline
• Can be a direct toxic effect on brain structures
• Can happen through liver disease
• Can happen through vitamin deficiencies
• The damage may be permanent
• Stopping alcohol use can sometimes reverse the problem
• NOT known to be associated with cognitive decline:
• Chronic pain¹⁷

References:

1. Frontiers in Pharmacology, February 2020.
2. Journal of Cardiac Failure, June 2017.
3. International Journal of Cardiology, August 2019.
4. Psychiatria Polska, February 2019.
5. Sleep Medicine Reviews, April 2020.
6. JAMA Neurology, October 2017.
7. Sleep Medicine, April 2020.
8. Journal of Alzheimer’s Disease, January 2020.
9. Journal of the American Heart Association, March 2020.
10. Journal of Neurology, September 2020.
11. Ophthalmology, May 2020.
12. The Journal of Prevention of Alzheimer’s Disease, January 2020.
13. Maturitas, January 2019.
14. Journal of Neurotrauma, September 2020.
15. Journal of Neural Transmission, August 2019.
16. The Lancet Public Health, March 2018.
17. PAIN, October 2020.