[Prolonged hospitalization as a risk factor for cognitive decline in older patients with atrial fibrillation]

Atrial fibrillation (AF) is associated with an increased risk of cognitive impairment (CI) and dementia in the elderly population, as is hospitalization, particularly when prolonged. However, the potential synergistic effect of both conditions in elderly patients remains unknown. Therefore, the objective of this study is to analyze the impact of prolonged hospital stay on cognitive function in patients over 80 years of age with AF.

An ambispective observational study was conducted on 400 patients aged> 80 years with AF admitted to a geriatric acute care unit between 2019 and 2022. Length of stay (LOS) was classified as normal (< 12 days), prolonged (13-15 days), and very prolonged (> 16 days). The primary outcome was the onset of CI at 12 months. Multivariable logistic regression models were applied to identify independent predictors.

The overall incidence of CI at 12 months was 18.9%, increasing progressively according to the duration of admission (15.4% in normal stays, 20.4% in prolonged, and 31.6% in very prolonged). In prolonged stays, functional dependence and frailty were significantly associated with the risk of CI, whereas in very prolonged stays, the main predictors were diabetes, valvular heart disease, and ischemic heart disease. Our results demonstrate that hospital stay not only increases the risk of CI but also modulates the profile of predictors based on its duration.

Prolonged hospitalization acts as a modulator of CI risk in elderly patients with AF. In intermediate stays, the risk is concentrated in frailty and functional dependence, while in very prolonged hospitalizations, chronic comorbidity especially diabetes and heart disease predominates. This pattern suggests a potentiating effect of hospitalization on cognitive decline.