Does Diabetes Impact Cognitive Abilities?

Almost everyone has at least heard about condition called diabetes. Diabetes is a serious chronic disease that can be managed through lifestyle changes and medication. Over 18 million US adults have diabetes, and other 41 million adults, ages 40 to 74 have pre-diabetes. Beside all possible complications that diabetes carry with it self- these last couple of years- there has been a lot of talking about possible diabetes impact on cognitive abilities of patient. Is all this true!? Well, how much diabetes is responsible for cognitive dysfunction in older people continues to be investigated.  There have been several researches on this subject which were done comparing cognitive functioning of older people with and without diabetes and results are confusing!  Today, although they not confirm it- most experts agree that cognitive functioning, beside diabetes, is probably also adversely affected by age, illness duration, glycemic control, and the presence of other co-morbid conditions which are common in older people! One other study has proven that older people with diabetes are at increased risk for dementia.  

Overview of Diabetes

What exactly should be known about diabetes mellitus?! Well, it represents one serious metabolic disorder characterized by hyperglycemia or high blood sugar! Beside this- there are also some other characteristic signs. Important thing to know is also that there are several types of diabetes, but, The World Health Organization recognizes three main forms, which have similar signs, symptoms, and consequences, but different causes. What's characteristic for all three types is that they are due to the beta cells of the pancreas being unable to produce enough insulin to prevent hyperglycemia!

Three types of diabetes are:

·        type 1 diabetes

This form of diabetes is usually due to autoimmune destruction of the pancreatic beta cells.

·        type 2 diabetes

It is important to point out that this form of diabetes is characterized by tissue resistance on insulin although there is enough insulin in the circulation.

·        gestational diabetes  

 Gestational diabetes is similar to type 2 diabetes, which means that it involves insulin resistance, but all this happens in pregnancy! How come?  Well, the hormones of pregnancy cause insulin resistance in those women genetically predisposed to developing this condition. Good thing about this form of diabetes is that gestational diabetes typically resolves with delivery.

Unfortunately- types 1 and 2 are incurable chronic conditions! This means that there is no definite cure, but have been treatable since insulin became medically available on the market!

“Usual” diabetes complications

It is well known fact that diabetes can cause several possible complications. They could be divided into acute and chronic! When we talk about acute complications we should know that the most common are:

·        hypoglycemia

·        ketoacidosis

·        nonketotic hyperosmolar coma

Some of the most common serious long-term complications include:

·        Cardiovascular disease – Experts are saying that you have double risk of developing heart disease

·         Chronic renal failure- Unfortunately, this complication is very serious and leads to diabetic nephropathy which later leads to life-term dialysis  

·        Retinal damage- It is well known that this complication leads to blindness  

·        nerve damage

·        Microvascular damage, which may cause erectile dysfunction (impotence) and poor healing of the wounds which can later lead to gangrene which can require amputation

Signs and symptoms

What are the most common symptoms of diabetes!? Well, everyone should know that there is so called -classical triad of diabetes symptoms. There symptoms are:

·        Polyuria- frequent urination

·        polydipsia - increased thirst  

·        polyphagia - increased appetite

How these symptoms occur!? Well, the mechanism isn't simple! Experts are saying that, when the glucose concentration in the blood is high, reabsorption of glucose in the patient’s kidneys is incomplete which means that one big part of the glucose remains in the urine. This condition is called glycosuria. Problem with this condition, beside sweet urine, is that it increases the osmotic pressure of the urine and that why- it inhibits the resorption of water by the kidney. You can assume what happens then- increased urine production or polyuria. This is also causing the dehydration and increased thirst.

When the concentration of glucose in blood is too high and prolonged- it can lead to several complications! First complication is usually changes in the shape of the lenses of the eyes, leading to vision changes. That’s why- interesting and important fact to know is that blurred vision is a common complaint leading to a diabetes diagnosis.

Diabetic ketoacidosis

What happens if patient do not regulate blood sugar properly!? Well, it that case- this leads to one condition called- diabetic ketoacidosis. It represents one serious and extreme state of metabolic dysregulation. In most cases it is characterized by:

·         the smell of acetone on the patient's breath

·         Kussmaul breathing

·         Polyuria

·         Nausea

·         vomiting

·         abdominal pain

Statistics

Several researches done in the past have showed that diabetes affects nearly 21 million people in the United States and 230 million people worldwide, according to the American Diabetes Association and the International Diabetes Federation.  Diabetes is in the top 10, and perhaps the top 5, of the most significant diseases in the developed world, and is gaining in significance there and elsewhere.

History of cognitive impairment people with diabetes

What should be known about link between diabetes and cognitive impairment!? Well, some of the latest researches made on cognitive functioning in older people with type 2 diabetes are telling a lot! According to these studies, when people with diabetes are compared to people without, there is a strong link between diabetes and several cognitive impairment conditions in elderly! How this could be explained!? Well, there are some problems that are causing difficulties with determining the right cause of all this! First of all, older people with diabetes usually also have other medical conditions that impair cognitive functioning, such as hypertension and cardiovascular disease. Another problem is also that there is a lack of consensus over the cognitive functions that should be investigated, as well as the instruments that should be used.  Cognitive abilities of one individual are extremely complicated thing which include several abilities such as abstract reasoning, verbal memory, and mental flexibility, and this is making things much more difficult!

Experts agree now that type 2 diabetes has been associated with an increased risk of developing dementia or Alzheimer’s disease.

Age of the patients with cognitive impairment

Although, we have mentioned several times that all this happen only to the people in advancing age- this isn't the complete true! The fact is that age does not seem to affect all areas of cognition and all older adults in the same way. Whatever we think about all this, the fact is that cognitive deficits have been observed in cross-sectional studies of younger, middle-aged, and older adults with diabetes. Therefore, conclusion could be that increasing age is not associated with level or type of cognitive impairment in older people with diabetes.

Conclusion

What is the definite conclusion of all these debates about diabetes and cognitive abilities? Well, the conclusion is simple- older people with type 2 diabetes are more likely to have some cognitive impairment compared to people without the illness. However, there are no rules or similar symptoms because such impairment is a very complex thing because of relatively complex cognitive processes! Other condition, accept the diabetes it self- can also contribute to the cognitive impairment, such as other disease of elderly! These can be confused with diabetes!  The precise extent and severity of cognitive impairment is unlikely to be established because of its complexity!