Lagarto L, Albuquerque E, Loureiro D, et al. - In acute medically-ill older individuals with and without prior dementia, researchers assessed the natural course of delirium and abnormal arousal states during hospital stay in this observational prospective study. This investigation was carried out in an acute male geriatric ward. To assess the level of arousal and the presence of delirium, individuals aged ≥ 65 years old were examined by a psychiatrist within 72 hours of admission, and every other day before discharge. According to the results, 43.5% of candidates in the final sample (n= 269) had dementia. Greater rates of moderate/severe hypoarousal and delirium at admission were linked to previous dementia. Especially in patients with previously reported dementia, moderate/severe hypoarousal is related to adverse outcomes and ought to be evaluated as part of delirium spectrum.