Preoperative screening for cognitive dysfunction including dementia among the elderly

Background Neurocognitive disorders are common perioperative complications in older patients, leading to a higher incidence of mortality and morbidity. Pre-existing cognitive impairment is the strongest predictor. As patients who do not have documented dementia may have mild cognitive impairment, evaluating their cognitive status before surgery is important for risk stratification and for subsequent prevention and management. We aimed to assess the magnitude of cognitive impairment and dementia among the elderly and to find out any possible correlation between various sociodemographic factors and comorbid conditions. Methods In this hospital-based, observational, crosssectional study, patients 65 years or older were screened for cognitive dysfunction using the Mini-Cog and 4 'A's test during pre-anaesthetic check-ups. Information regarding sociodemographic profiles and clinical conditions was also collected. Data were analysed using standard statistical tests. Results Most study subjects were men aged 65-70. The prevalence of dementia was 40%, possible cognitive impairment was 43.43%, and delirium was 6.29%. As age increased, the prevalence of cognitive dysfunction also increased and was higher among men, and patients belonging to lower education levels and lower socio-economic status. Significant association of cognitive dysfunction was found with age, gender, socioeconomic status, level of education, past cerebrovascular accident (CVA)/transient ischaemic attack (TIA), and myocardial infarction (Ml). Conclusion There is a significant prevalence of cognitive impairment and dementia among the elderly being assessed for surgery in eastern India.