Alcohol use and in-hospital complications in patients aged 80 years and older: a multicentre observational study in Spain.

Background Alcohol consumption among adults aged ≥ 80 remains understudied, despite their vulnerability to alcohol-related harm. We aimed to assess the prevalence of alcohol use and AUD and to examine associations with in-hospital complications in very elderly hospitalized patients. Methods This was a prospective, multicenter observational study conducted from June 2022 to July 2023 across 19 hospitals. Consecutive patients aged ≥ 80 admitted to Internal Medicine departments were included. Alcohol consumption was ascertained via structured interview and screening tools (AUDIT, CAGE). Data on comorbidities, medications, functional status, laboratory parameters, and in-hospital complications were collected. Logistic regression identified independent predictors of complications. Results A total of 916 patients (median age 86 years; 54% female) were analysed. Active alcohol use at admission was reported by 28%, and 8% met AUDIT criteria for AUD. Documentation of alcohol use in medical records was present in 36%. Overall, 47% developed at least one complication; withdrawal syndrome (9%) and insomnia (36%) were significantly more frequent among active drinkers. Independent predictors of complications included AUDIT ≥ 8 (OR 3.8; 95%CI 1.8–8.3), in-hospital benzodiazepine use (OR 2.3; 95%CI 1.7–3.2), neuroleptic use (OR 4.1; 95%CI 2.9–5.7), and discharge diagnoses of infection or neurological disease. Conclusions Alcohol consumption is common but under-recognised in patients aged ≥ 80 and is associated with increased risk of in‐hospital complications. Routine screening with AUDIT in this group may identify high-risk individuals and inform preventive strategies to mitigate adverse hospital outcomes.