Effects of Type II Diabetes on Cognitive Functions in Middle-aged Patients

Sixty patients with type 2 diabetes will be recruited from the Tampere Diabetes outpatient clinic. Inclusion criteria for the patients are type 2 diabetes diagnosis, diabetes medication and age 35-65. Exclusion criteria are type 1 diabetes, hypothyreosis, neurological or psychiatric disorder, substance abuse and serious diabetes complications. Sixty healthy control persons are recruited from the personnel and occupational health care. Exclusion criteria for controls are type 1 or 2 diabetes, hypothyreosis, neurological or psychiatric disease and substance abuse.

A comprehensive neuropsychological assessment is made to all participants.The assessment consists of standardized neuropsychological tests, questionnaires and interview. Domains assessed include attention, executive functions, memory, information processing speed, general cognitive functioning, depressive symptoms, anxiety and fatigue. Medical information (such as glycated hemoglobin and blood pressure) from the patients is gathered from the medical records. Corresponding information from the control participants is gathered with medical examinations including laboratory tests. Informed consent is taken from all participants.

This study will examine the difference in cognitive functions between healthy controls and middle-aged patients with type 2 diabetes. There is evidence from previous studies that type 2 diabetes is related to an increased risk of dementia, but the association between diabetes and cognition at younger ages is less studies. The difference in mood and fatigue is also studied between the groups. In addition, the association between glycated hemoglobin level and cognitive functions is examined in patients, as poor glycemic control has been implicated to impact on cognitive decline in previous studies. Finally, the association between history of hypoglycemic episodes and cognition is studied.