Depression and diabetes mellitus - a common occurence, risk factors and patophysiological mechanisms
Abstract
Depressive symptoms occur in 31% patients wirh diabetes mellitus (DM). In patients with DM risk for development of depression is two times higher in comparison with general population.
Some risk factors are known - demographic (female gender, younger age, lower education, powerry), clinical (severiry of diabetes, disorder length, complications of diabetes, increased levels of glycosyled haemoglobin HbA1c), behavioural (smoking, obesity), which are more or less related to occurence of depression in patients with diabetes. The endocrine and neurotransrnitter changes include decreased concentrations of catecholamines, mainly 5-HT, stimulated production of glucocorticoids, growth factor and glucagon, which counteract the hypoglycaemic action of insulin.
Increased cortisol levels are observed equally in patients with diabetes and depression, as well as impaired glucose tolerance and the development of insuline resistance. Common occurrence of these two disorders is not a random phenomenon, which implies their possible relationship.
Depression arises as a direct result of neurochemical changes associated with diabetes or as a result of psychosocial factors related to disease/treatment. On the other hand depression is an independent risk factor for diabetes.