EPIDEMIOLOGY OF THE MOST COMMON MENTAL DISORDERS IN PATIENTS WITH DIABETES MELLITUS

Background: Non-psychotic mental disorders including non-severe depressive, anxiety and organic disorders can have an impact on the course and prognosis of the underlying disease in patients with diabetes mellitus (DM). Therefore, assessment of their epidemiologic aspects is extremely important. Aim:  Investigation of the types and prevalence of the major mental disorders among both type 1 DM (T1DM) and type 2 DM (T2DM) in-patients, determination of possible etiology of the organic involvement of the brain in T1DM patients as well as of the rate of diagnostics and management of mental disorders in DM patients in routine medical practice. Materials and methods: Part 1 was a cross-sectional study in 228 consecutive DM patients aged from 18 to 75 years, aimed at detection of current mental disorders. Part 2 was a cross-sectional study in 72 consecutive T1DM patients with in-depth assessment of signs of organic brain involvement. All patients underwent cognitive function tests. Mental disorders were diagnosed by a psychiatrist according to ICD-10 diagnostic criteria. Results: Mental disorders were  found  in 80.3% of patients, being significantly more prevalent in patients with T2DM (87.9%) than in T1DM patients (57.4%, р<0.0001). Anxiety disorders as a whole were diagnosed as frequently as depressive ones (39.5% and 40.0%, respectively), being the most prevalent both in T1DM (35%) and T2DM (60%). Within the class of anxiety disorders, diabetes-specific phobias of injections and hypoglycemia were noted 8-fold more often (р<0.01) in T1DM than in T2DM patients. Generalized (22.4 versus 9.3%) and organic (18 versus 0%) anxiety disorders as well as unipolar depressive episodes and dysthymia (40.2 versus 25.9%, р<0.05) occurred considerably more often in T2DM than in T1DM patients. In total, signs of organic brain involvement were found in 37% of T1DM patients. Possible etiologic factors of organic brain disorders were as follows: craniocerebral injury including concussion of the brain, severe hypoglycemia, and diabetic ketoacidosis – in 40.7% of patients each; alcohol abuse – 30.7%; arterial hypertension – 22.2%; ante- and intranatal factors – 11.1%; neuroinfections/intoxications and occupational neurotropic factors – in 7.4% each; electric trauma, general malnutrition, stroke, and brain tumor – in 3.7% each. None of the listed potential causes could be found only in one patient with organic brain involvement (3.7%). In T1DM patients, organic brain involvement was nonspecific, and there was no evidence of its association with the level of glycated hemoglobin, acute and chronic vascular diabetic complications. Conclusion: The present investigation revealed a high prevalence of non-severe mental disorders with predominance of generalized anxiety disorders and unipolar protracted depressions in T2DM in-patients and specific phobias in T1DM patients. Organic brain involvement (encephalopathy) occurs in every third young T1DM patient; however, in the majority of cases, its potential etiology is linked with factors unrelated to DM or non-specific for DM (for example, hypoglycemia). In routine medical practice, diagnostics and treatment of mental disorders in DM patients are close to non-existent.