Prevalence and risk factors of delirium and subsyndromal delirium in Chinese older adults

摘要

Aim To study the prevalence and risk factors of delirium and subsyndromal delirium (SSD) in Chinese older adults with acute medical illnesses. Methods A prospective cohort study was carried out in acute general medical wards in a university-affiliated hospital in Hong Kong. Patients were assessed by the confusion assessment method by geriatricians within 6 h after admission and classified into three mutually exclusive groups, namely delirium, SSD and those without both conditions. Predisposing factors and precipitating factors of delirium and SSD were retrieved from collateral information, clinical charts and electronic clinical records. Results A total of 575 patients with mean age of 80.8 years were recruited. A total of 73% of the patients did not have delirium, 15.8% of patients had delirium and 11.3% of patients had SSD. On multivariate analysis, patients with delirium or SSD were more likely to be current users of psychotropic medications, had hearing and visual impairment, had a major neurocognitive disorder as defined by the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, and with a lower Barthel Index 20 points version than those without both conditions. Significant predisposing and precipitating factors of delirium included psychotropic medications, acute stroke and other causes of organic brain syndromes. Predisposing and precipitating factors of delirium and SSD were almost identical. Conclusions Delirium and SSD are common among Chinese older adults with acute medical illnesses, with a combined prevalence of delirium and SSD of 27%. Important precipitating and predisposing factors include psychotropic medications, acute ischemic stroke and other causes of organic brain syndromes. Geriatr Gerontol Int 2018; 18: 1625-1628.