A number of medical conditions can interfere with memory and the ability to process information.
For example, 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 (a significant intellectual decline that persists over time and affects several areas of cognition, or thinking) if he or she has a prior history of psychiatric illness, a sudden onset of memory and thinking problems, trouble sleeping, or a rapid decline in the ability to perform everyday activities. Because depression and the mental processing problems of dementia can be difficult to distinguish from one another, a doctor may suggest that a patient start antidepressant therapy and then return for a reassessment once the therapy has had time to take effect.
Other medical conditions that can lead to memory problems include hormonal imbalances from thyroid disease or Cushing’s disease (an overproduction of steroid hormones by the adrenal glands), and AIDS and other chronic infectious diseases. It’s also possible for memory difficulties to result from a tumor in certain parts of the brain, a subdural hematoma (a collection of blood between the skull and the brain), and normal pressure hydrocephalus (from excess fluid in the brain).
Heart failure, with its decrease in the heart’s ability to pump blood, is another example of a health condition that can impede mental functioning by reducing the amount of blood circulating to the brain. The process of recovering from cardiac arrest or heart bypass surgery also can affect memory; research suggests that about 50 percent of people who undergo heart bypass surgery experience a decline in cognitive function. The cognitive problems were thought to be related to the heart-lung machine used during the surgery. Unfortunately, even use of the newer “off-pump” bypass units, which don’t involve a heart-lung machine at all, don’t lessen the risk of cognitive changes.
Some research suggests that over time, sleep-disordered breathing, such as obstructive sleep apnea, can take a toll on memory and the ability to think clearly. Evidence of a connection was put forth in an analysis that combined data from 14 studies involving more than 4.2 million adults. The research, published in the journal JAMA Neurology in 2017, showed that people with sleep-disordered breathing were 26 percent more likely to experience cognitive decline than those who didn’t have such breathing troubles. And a 2015 study in the journal Neurology reported that heavy snoring and sleep apnea may accelerate cognitive decline in older adults.
Additional conditions linked to memory issues include strokes (even minor ones), hearing or vision loss, the use of certain medications, vitamin deficiencies, and stress. Long-term heavy use of alcohol is commonly implicated in dementia, though stopping alcohol abuse may reverse the problem.
Sometimes, effectively treating health problems may alone improve your memory. If you suspect that you are having memory difficulties, talk to your doctor about what’s going on.