With type 2 diabetes on the rise, it
can actually be regarded as an epidemic propagating as a consequence
of poor lifestyle choices, bad feeding habits and a sedentary life.
The International Diabetes Federation (IDF) estimates that there are
over 380 million cases of diabetes throughout the world and predict
that it may rise to around 600 million in the next 20 years.
One of the consequences or
complications of diabetes is cognitive decline. There are several
studies showing that diabetes causes an acceleration of age-related
cognitive decline. But it’s not just age-related cognitive
decline, patients with diabetes also have a higher risk of developing
cognitive decline associated with different brain pathologies.
Diabetes increases the likelihood of developing vascular diseases,
Alzheimer’s disease, mild cognitive impairment and dementia.
Although these diseases have different onset mechanisms, they can all
be intensified by diabetes.
Hyperglycemia is known to increase
neuronal cell death through oxidation processes and generation of
free radicals, thereby having neurodegenerative effects.
Hyperglycemia can also cause damage to blood vessels through
inflammatory mechanisms, leading to reduced blood flow to the brain
and, consequently, reduced oxygen delivery, which results in the
development of brain injuries.
If we add hypertension to the equation,
which is commonly observed in patients with diabetes, vascular
deficits become even worse, increasing the risk of stroke, for
example, which is indeed more common in diabetic patients.
This effect of diabetes is not only
observed in the elderly. Although type 2 diabetes accelerates
age-related cognitive decline, younger patients also show signs of
cognitive impairment. In a study that followed dementia-free
diabetic patients with a mean age of 40 years at the start of the
study it was shown that, seven years later, diabetes had led to a
degradation of memory, visual perception, and attention performance,
as well as to a loss of brain integrity. Diabetes and higher fasting
blood glucose levels were correlated with gray matter loss in the
brain. This shows that cognitive decline is clearly anticipated in
diabetes patients.
Another study, which followed patients
with an average initial age of 54 throughout 10 years, showed that,
compared with healthy participants, those with diabetes had a 45%
faster decline in memory (10 year difference in decline), a 29%
faster decline in reasoning, and a 24% faster decline in the global
cognitive score. Furthermore, diabetes patients who had a poorer
glycemic control had a faster decline in memory and reasoning, while
participants with pre-diabetes or newly diagnosed diabetes had
similar rates of decline to those with normal glycemia.
It seems that the earlier the onset of
diabetes, the higher the risk of accelerated cognitive decline. And
even teenagers can be affected by the neurological consequences of
type 2 diabetes. A pilot study following adolescents with type 2
diabetes showed that there are significant volume losses in a number
of areas of the brain, as well as reduced white matter integrity.
Given the fast increase in the incidence of type 2 diabetes (and
other metabolic diseases) that is being observed in teenagers, this
is clearly a reason for concern.
Therapeutic strategies designed to
control glycemia will most likely help reduce the effects of diabetes
on the brain. Many of the mechanisms of diabetes-associated dementia
and cognitive impairment can be counterbalanced by a good diet and by
exercise. Early intervention is fundamental. Yet our doctors are
not knowledgeable in how to do this and don't understand nutrition.
Just to show how important diet and
exercise are to diabetes care: there is scientific evidence showing
that lifestyle changes are actually more effective than antidiabetic
drugs. But instead of using diet and exercise as a way to control
all the detrimental effects of diabetes, it would actually be better
to use them to prevent it. Diet needs to be thought of as a way of
eating and lifestyle of eating and not as a diet.
