Major or Mild Neurocognitive Disorder Due to Another Medical Condition: In the DSM-5 the term cognitive disorder (disorders involving thinking) has been replaced by the diagnostic categories of mild neurocognitive disorder or major neurocognitive disorder. The distinction between the two is that in its mild form, a neurocognitive disorder does not significantly affect the person's ability to perform their daily activities. People who are diagnosed with a major neurocognitive disorder have serious problems and need assistance.
There are many identified causes for neurocognitive disorders. These can include irreversible medical conditions such as Alzheimer's disease, Lewy body dementia, and others. In addition, neurocognitive disorders that may be partially reversible can happen because of other types of medical conditions. The diagnostic category used to specify these conditions is major or mild neurocognitive disorder due to another medical condition. The criteria to diagnose this are:
- The person must first meet the criteria for mild or major neurocognitive disorder.
- There is evidence that the person's disorder is a result of some other medical condition that is not specified elsewhere in the DSM-5.
There are literally hundreds of conditions that can lead to cognitive (thinking abilities) problems in people. Some of these conditions may be reversible and others may not be fully reversible. Some of the most common are:
Normal Pressure Hydrocephalus (NPH): This is a disorder that happens when the fluid in the brain and spinal cord accumulates in the ventricles (the cavities or spaces in the brain). This creates pressure within the skull. It leads to issues with walking, memory, and incontinence (being able to hold one's urine). When this condition is corrected, many of the thinking problems will often resolve to some extent.
Disruption of Hormones: The endocrine system produces chemical substances that are transported through the bloodstream and control many of the body's activities. These substances are referred to as hormones. Hormones are different from neurotransmitters in that hormones work throughout the body and are transmitted through the bloodstream. Neurotransmitters are exchanged directly between the neurons (nerve cells) in the brain. There are many hormonal imbalances that can result in cognitive disorders including problems with insulin and with an excess or deficiency of thyroid hormone.
- Problems with insulin such as diabetes can often be corrected with medications, and any cognitive issues will often be resolved.
- Hyperthyroidism happens when there is an overproduction of thyroid hormone. This condition can be corrected with medications or with surgery. Cognitive issues that occur with the condition will typically clear up after treatment.
- Hypothyroidism occurs when there is an underproduction of thyroid hormone. This is usually treated with hormone replacement. The kind of issues associated this condition may or may not fully resolve.
Nutritional Problems: People who do not receive sufficient amounts of certain vitamins or minerals may develop cognitive problems. In most of these cases, the vitamin or nutrient that is lacking is water-soluble (dissolves in water such as vitamins B and C) and is required daily. If the situation can be corrected early in its presentation, any cognitive problems will often resolve. For instance,
Wernicke's Korsakoff syndrome happens because of the lack of vitamin B1 (thiamine) in the diet. This can produce many problems including severe memory issues. The syndrome is often seen in chronic alcoholics who do not eat properly. It can also be seen in people who have bariatric (weight-loss) surgery, cancer, or some other condition that results in them not eating properly. If the situation is recognized early enough, and the person is given supplements, the thinking problems may fully resolve. If this does not happen, the problems may be permanent.
Deficiencies with vitamin B12 can produce confusion and problems with memory. This may resolve if the person takes supplements and corrects their diet. Dehydration: People who become dehydrated can become confused and display severe issues with memory. If these people are hydrated, they often experience a complete reversal of their cognitive issues. However, in chronic (ongoing) cases of dehydration in the elderly, these problems may not fully resolve once the situation is corrected.
Infections: There are many infections that can result in the development of cognitive problems, particularly in elderly people. If the situation can be corrected early enough, the problems may resolve. In elderly people, infections of the urinary tract often lead to serious cognitive problems that may look like dementias such as Alzheimer's disease. If the person can be treated quickly enough, the cognitive problems will often resolve.
Medication/Drug Effects: The side effects of many medications can include a disruption of a person's thinking. Typically, either stopping the medication or adding another medication can help resolve these problems. Elderly people often forget to take their medications or may take too much. This can result in cognitive issues that appear like dementia, but can often be reversed by simply correcting the problem. Drug and alcohol abuse is a well-known factor that can lead to cognitive problems that can be serious, and even resemble, dementia. Depending on how long the person has abused drugs or alcohol, and if the situation can be corrected, the person may experience a complete reversal of these thinking problems. However, in some cases, this may not happen if there is been significant brain damage.
Sensory Deficits: An often unrecognized, but common issue in elderly people that contributes to the idea that they have cognitive problems is hearing loss. People who have severe hearing loss may appear as if they have a severe form of dementia. Therefore, using corrective devices, such as hearing aids, may result in a significant improvement in the appearance of thinking problems.
Again, there are literally hundreds of different conditions that can lead to the appearance of dementia, or can result in problems with thinking abilities. Many times, simply correcting the problem can result in significant improvement in the person's thinking. However, this is not always the case.