NLR and PRL in Neurocognitive Disorders

Inclusion Criteria: * 45 - 80 years * American Society of Anesthesiologists physical status I to III * elective general, urological, gynecological and orthopedic surgery under general anesthesia * native speakers of the Greek language Exclusion Criteria: * refused to participate or sign the informed consent form * had undergone surgery or anesthesia within the last 30 days * had any prior or current history involving an affliction of the central nervous system * were diagnosed with severe cognitive decline based on the 16 - item Informant Questionnaire on Cognitive Decline (IQCODE - 16) * suffered from severe hearing or visual impairment * any psychiatric disorder * had a score \>5 in the Geriatric Depression Scale (GDS - 15) * or a score in females \< 4 males \< 2 in the Lawton - Brody Instrumental Activities of Daily Living Scale (I.A.D.L.) * reported alcohol consumption \> 35 units/week * drug dependence * had undergone previous neuropsychological testing * Diabetes Mellitus type II with \> 10 years of diagnosis * Diabetes Mellitus type I * Hemoglobin A1c (HbA1c) \> 7.5% * suffered from hemodynamical instability (\> 20% alterations of blood pressure perioperatively) * or desaturation (one or more events of SpO2 \< 80% for more than 2 minutes) peri-operatively * or blood loss of more than one unit