Arousal changes and delirium in acute medically-ill male older patients with and without dementia: a prospective study during hospitalization.

Objectives: Previous research has characterized the prevalence, natural course and outcomes of delirium superimposed in dementia but much less is known about the relation between preexisting dementia and the emergence of altered arousal (such as drowsiness, obtundation, stupor or agitation) during acute medical illness. This study aimed to determine the natural course of delirium and abnormal arousal states in acute medically-ill older patients with and without prior dementia during hospital stay.Methods: Observational prospective study in an acute male geriatric ward. Patients aged ≥ 65 years old were assessed by a psychiatrist within the first 72h of admission and in every other day until discharge to determine the level of arousal and the presence of delirium. Prior cognitive impairment, sociodemographic data, chronic comorbidities, psychotropic prescription and functional status were assessed at baseline.Results: 43.5% of participants in the final sample (n= 269) had dementia. Prior dementia was associated with higher rates of moderate/severe hypoarousal (29.9% vs. 4.6%; p<0.001) and delirium (20.5% vs. 7.2%; p<0.001) at admission. RASS ≤ -3 at admission predicted a 4-fold increased intra-hospital mortality risk and RASS ≠ 0 had a sensitivity of 82.8% and a specificity of85.9% for delirium.Conclusions: Moderate/severe hypoarousal is associated with adverse outcomes and should be assessed as part of delirium spectrum, particularly in subjects with prior dementia.

Identification of sub-groups in acutely ill elderly patients with delirium: a cluster analysis.

BACKGROUND: Delirium is a serious neuropsychiatric syndrome affecting mainly elderly participants with acute medical diseases. The pathophysiology of delirium remains poorly understood as it involves complex dynamic interactions between a diversity of risk factors. Exploring how etiological factors interact with each other can clarify the pathophysiological mechanisms and facilitate the early identification of this syndrome. The aim of this study was to explore how different risk factors co-occur in medically ill elderly patients with delirium with cluster analysis and identify clinically meaningful sub-groups in this population. METHODS: A cross-sectional study was developed. Ninety-nine elderly inpatients admitted to acute medical wards diagnosed with delirium during hospitalization were selected. For each patient sociodemographic characteristics, acute and chronic medical conditions, laboratory parameters, and current medication were collected. RESULTS: The cluster analysis extracted three distinct subgroups of participants with delirium. Patients in cluster 1 (n = 28) had higher rates of medication with anticholinergic proprieties. Cluster 2 (n = 29) included participants with cardiac and pulmonary comorbidities associated with both chronic and acute reduction of blood flow and/or oxygenation to the brain. Cluster 3 (n = 42 patients) comprised patients with simultaneous deregulation of different organs/systems, such as electrolytic disturbances, metabolic disturbances, and acute renal failure. Known predisposing factors of delirium, such as age and pre-existing dementia, were similar between groups. CONCLUSIONS: The results reveal different patterns of clinical characteristics in elderly patients with delirium. This is relevant to clinical care of acute medically ill patients and suggests that different pathways are implicated in delirium pathophysiology.

The immunology of delirium.

Delirium is an acute neuropsychiatric syndrome characterized by acute-onset global cognitive deficits, perceptual and behavioural disturbances affecting mainly elderly subjects with underlying medical or surgical conditions. The pathophysiology of delirium is complex and inflammation is a relevant precipitant factor of this syndrome, although it remains unclear how acute systemic inflammation induces the clinical picture of delirium. The central nervous system is able to detect peripheral infection or tissue destruction through circulating immune mediators and neural ascending signs. Activated microglia is responsible for an acute neuroinflammatory reaction underlying the symptoms of sickness. In healthy conditions descending pathways from the paraventricular nucleus, locus coeruleus and dorsal motor nucleus organize a centralized response to influence the immune response at the periphery and restore homeostasis. In the context of ageing and chronic neurodegeneration, adaptive changes to acute insults are characterized by exaggerated production of pro-inflammatory cytokines by primed microglia coupled with dysfunction of brain-to-immune pathways. In animal models, these changes underlie a more severe manifestation of sickness behaviour with working memory deficits suggesting that inattention, a core feature of delirium, can be a clinical correlate of an increased neuroinflammatory reaction. In patients with delirium, higher levels of pro-inflammatory cytokines and cortisol were identified in plasma and cerebrospinal fluid. However, to date it has not been clarified how peripheral inflammatory or endocrine biomarkers can reflect the likelihood or severity of delirium symptoms. In the future, a better understanding of the interaction between the brain and peripheral organs and the exact mechanism by which systemic inflammation can lead to delirium, will allow the development of new therapeutic agents.

Improving quality of care: focus on liaison old age psychiatry.

Introduction Elderly patients occupy up to 65% of acute hospital beds and a significant proportion of them present with a comorbid psychiatric condition such as depression, delirium or dementia. Liaison old age psychiatry (LOAP) services have been developed to provide psychiatric consultation in medical and surgical settings, improving at the same time the knowledge and expertise of general ward staff. Objective The aim of this study is to evaluate clinical characteristics across different psychiatric disorders among elderly patients in medical wards. Method A prospective observational study was developed between October 2011 and January 2013, which involved 107 subjects aged 65 years or older that were hospitalised in the Department of Internal Medicine and referred to the LOAP service. Psychiatric diagnostic was assessed using the Confusion Assessment Method, the Geriatric Depression Scale, the Mini-Mental State Examination and the Clinical Global Impression Scale. Results Delirium (40.6%), depression (22.4%) and dementia (20.4%) were the most common psychiatric diagnoses. Patients with delirium were significantly older, had more severe psychiatric symptomatology (mean CGI = 5.35) and presented infectious processes as acute medical conditions more frequently than the other patients. Conclusion Psychiatric disturbances occurring in elderly inpatients in medical wards are highly prevalent and complex. A LOAP service may play an important role in effectively reducing the overutilisation and consumption of health resources through early recognition of these conditions, effective management and prevention of adverse outcomes, and effective communication with out-patient clinics, community mental health teams and day-care centres.