Abstract
Delirium is recognized as a key healthcare target for our increasingly aged society. Improved management of delirium and related neuropsychiatric presentations can allow for significant improvements in outcomes but requires fundamental change in the structure of healthcare services. There is a pressing need for cognitive-friendly hospital programmes that can increase awareness of delirium, provide better education around its management, improve detection in real-world practice, and promote evidence-based management of cognitive problems in the general hospital. We outline key elements of delirium-friendly services that span interventions in our day-to-day clinical care of individual patients all the way to wider organizational practices.
Introduction
Delirium is recognized as a key healthcare target for our increasingly aged society. Improved management of delirium and related neuropsychiatric presentations can allow significant improvements in outcomes but requires fundamental change in the structure of healthcare services. There is a pressing need for cognitive-friendly hospital programmes that can increase awareness of delirium, provide better education around its management, improve detection in real-world practice, and promote evidence-based management of cognitive problems in the general hospital. We outline key elements of delirium-friendly services that span interventions in our day-to-day clinical care of individual patients all the way to wider organizational practices.
Delirium: A Key Healthcare Challenge
In 1998, one in six people (15.9%) in the UK was aged over 65 years. By 2018 this had increased to almost one in every five (18.3%) and is projected to reach one in every four (24.2%) by 2038. This increasingly aged society brings with it increased multimorbidity, general frailty, cognitive impairment, and dementia. Alongside this increasing burden, resource-pressurized healthcare services are struggling to respond to the complex needs of older persons. The care challenge posed by delirium represents a particular example of how we need to adapt towards more cognitive-friendly care practices.
Delirium is a common serious neuropsychiatric disorder that occurs across healthcare settings. The impact of delirium is particularly apparent in the acute general hospital setting, where there is a concentration of vulnerable populations such as frail elderly with pre-existing cognitive impairment. Point prevalence studies indicate that delirium can be identified in 20–25% of the hospitalized elderly, with higher rates in specific groups, such as older patients with severe medical illness or pre-existing cognitive impairments, terminal illness, or those receiving intensive care facilities. One study across a complete general hospital in Ireland identified an 18% point prevalence of delirium,1 while a point prevalence study of delirium status in 1,867 older patients across 108 acute and 12 rehabilitation wards in Italian hospitals found 23% with delirium.2
Delirium is also highly prevalent in community-based settings such as nursing homes. The all too common practice of early discharge of patients, often despite continued significant morbidity, to post-acute and community-based facilities means that improving delirium awareness among primary care practitioners is key. A recent point prevalence study of 71 nursing homes across Italy found that 37% had active delirium at assessment.3 In a cohort study of 12 nursing homes in Canada, 40% developed at least one episode of delirium over three years.4 Delirium is highly predictable by virtue of well-identified risk factors such that pre-hospital preparation can substantially reduce delirium risk during elective admissions.
Delirium is a significant independent predictor of adverse health outcomes, including longer duration of hospitalization, reduced subsequent functional independence, reduced cognitive functioning, and elevated mortality.5 The economic impact of delirium is highly significant, with direct one-year US healthcare costs of $152 billion – comparable to cardiovascular disease ($257.6 billion).6 In the UK, a health economic analysis of elderly acute medical patients found that 12-week costs for patients with delirium were more than double the costs of those without delirium.7
Delirium as a major source of health and economic burden thus has unrivalled penetration across healthcare services. The emergence of organizations (e.g. European Delirium Association, American Delirium Society) has promoted greater clinical and research effort with delirium but everyday management remains far from optimal as delirium continues to be underappreciated in healthcare planning.
O’Connell et al. described a model for improved delirium care through more cognitive-friendly hospitals.8 This includes a multifaceted approach to reducing incidence, improving detection, and providing more targeted management focusing on seven levels of care: patient, task, staff, team, environment, organization, and institution, while addressing key barriers to cognitive-friendly practices such as inadequate assessment, inappropriate intervention, stigma, and deficiencies in staff levels and training. We revisit this model from a societal perspective, again focusing upon hospital practices but also exploring how efforts away from hospital can contribute to reducing the healthcare burden of delirium and related conditions too.
The Nosology of Delirium and Related Disorders
Historically, acute generalized disturbances of cognition have been referred to by more than 50 synonyms, each reflecting delirium occurring in particular populations or treatment settings (e.g. ‘confusional state’, ‘encephalopathy’, ‘acute brain failure’) and tending to confuse clinical practice. In 1980, DSM-III introduced ‘delirium’ as the umbrella term to replace these concepts while providing systematic criteria for delirium diagnosis that have evolved to the current DSM-5 criteria.9
These categorize delirium as a major neurocognitive disorder based upon five key criteria (see Box 19.1) that reflect the occurrence of generalized disturbance of brain function (evidenced by cognitive and neuropsychiatric symptoms with inattention and reduced awareness being central) that is relatively recent in onset, tends to fluctuate, and occurs in the context of physical morbidity. Delirium symptoms can present as sub-syndromal illness where full syndromal criteria are lacking and in such cases outcomes are typically intermediate between delirium and non-delirium.10
A. A disturbance in attention (i.e. reduced ability to direct, focus, sustain, and shift attention) and awareness (reduced orientation to the environment).
B. The disturbance develops over a short period of time (usually hours to a few days), represents a change from baseline attention and awareness, and tends to fluctuate in severity during the course of a day.
C. An additional disturbance in cognition (e.g. memory deficit, disorientation, language, visuospatial ability, or perception).
D. The disturbances in Criteria A and C are not better explained by a pre-existing, established, or evolving neurocognitive disorder and do not occur in the context of a severely reduced level of arousal, such as coma.
E. There is evidence from the history, physical examination, or laboratory findings that the disturbance is a direct physiological consequence of another medical condition, substance intoxication or withdrawal, or exposure to a toxin, or is due to multiple aetiologies.
In addition, the concept of Post-Operative Cognitive Disorder (POCD) has emerged to account for the many patients who are diagnosed with new cognitive impairments in the early post-operative period which persist beyond what is traditionally considered as delirium.11 The incidence of POCD among older patients is approximately 26% at one week and 10% at three months following surgery.12 Unlike delirium and dementia, POCD lacks a clear definition in DSM-5 with a positive diagnosis based upon a difference in preoperative and post-operative test scores that equates with a z-score two standard deviations from the mean. There is also a lack of clarity around its relationship to both delirium and dementia – many cases are preceded by delirium but this is not invariable. Also, it remains uncertain whether POCD is part of a continuum that culminates in dementia or is a distinct entity that is, for example, relatively static compared to the conventional notion of a progressive dementia. To date, studies have linked POCD with reduced thalamic and hippocampal volumes and reduction of cerebral blood flow.13
In short, while dementia is a major risk factor for developing delirium (and underpins delirium in approximately 50% of cases), increasing evidence implicates delirium as not only a marker for emerging dementia, but as an aggravating factor in dementia that accelerates its course and is an independent risk factor for long-term cognitive impairment which can persist and in some cases is irreversible.
What Does Cognitive-Friendly Mean?
When applied to healthcare, cognitive-friendly refers to practices and the environment in which they occur that promote optimal cognitive functioning while minimizing the likelihood and impact of neurocognitive disorders. As such, it refers to the combined impact of both structural and functional elements in providing an environment that is sensitive to the vulnerabilities of those prone to delirium and related conditions. The lived environment is the arena where our cognitive skills, preferences, and attitudes come together to determine our ability to interact with the world.14 Environmental design is an important contributor to cognitive functioning; the ability to form cognitive maps is a key element in the orientation process that declines with age. Cognitive-friendly environments are engaging and appropriately stimulating in a way that facilitates cognitive performance. Avoiding clutter and excessive perceptual complexity (e.g. the number of different colours in an environment), simplicity of design to ease wayfinding, and providing facilities that promote the capacity for social interaction all make the environment more navigable for cognitively impaired patients, which in turn promotes a sense of efficacy.15 Environments should also promote physical activity, which is associated with better cognitive performance in older age. Early mobilization after procedures is one example of how promoting engagement with one’s surroundings can positively impact upon cognitive outcomes.
From a functional perspective, efforts to provide cognitive-friendly services need to occur across the healthcare system, such that cognitive difficulties are also addressed both before and after periods of hospitalization. Programmes that are ‘senior-friendly’ flag persons with pre-existing cognitive issues at entry to hospital as at higher risk throughout their hospital journey and undertake proactive delirium prevention measures and rapid assertive intervention in the event of emerging delirium. A range of evidence-based interventions can reduce the risk of experiencing incident delirium in hospital,16 and have demonstrated cost-effectiveness.17
A cognitive-friendly hospital considers the entire patient ‘journey’ in terms of the different clinical areas and services within the general hospital, from points of access to care (e.g. emergency department), through to areas of continuing care (e.g. medico-surgical wards, intensive or palliative care), and appropriate discharge planning. This facilitates cohesive multicomponent intervention that is tailored to particular patient needs at different points of the at-risk versus active episode versus post-episode recovery spectrum. These efforts should also link effectively with primary and community care settings, where possible before, and always after hospital admission.
The Delirium Experience, Education, and Action
Increasing staff awareness and expertise in managing patients with cognitive disorders is an essential first step in the development of a cognitive-friendly hospital programme. However, such efforts have limited impact unless they are aligned to changes in clinical practice. These include flagging patients who have known difficulties (e.g. the butterfly scheme) along with specific screening practices (e.g. cognitive vital sign monitoring), identifying specific dementia champions to promote better awareness and practices, and providing access to specialist supports such as a dementia specialist nurse to advise on specifics of care.
It is increasingly recognized that caregiver-centred detection tools such as the FAM-CAM and Sour Seven can improve delirium detection.18 In addition to front-line medical and nursing staff, allied healthcare professionals, care attendants, and non-clinical staff with high levels of patient contact (e.g. cleaners and catering staff) can be included in efforts to identify and best manage delirious patients as subtle changes in eating and hygiene/self-care can assist in delirium detection.
Central to providing more delirium-friendly care environments is understanding and integrating knowledge derived from recovered patients. This patient perspective has been previously underappreciated owing to the erroneous belief that delirious patients lack the capacity to communicate their perspective and experiences usefully. Recent studies indicate that, even during an episode, many patients can usefully communicate that they are confused – with more than a third recognizing their own loss of functionality as feeling confused or mixed-up.1
Qualitative studies have identified care practices that connect best with patients, including simplicity, repetition, reassurance, and clarity of communication. Garrett provides a particularly coherent account of his experiences during a delirious episode and how a change in the environment fuelled further disturbing experiences:
On moving out to the surgical ward I became paranoid. Convinced that I was in a small, poorly funded cottage hospital, I was certain that the staff resented having me there, as I was a serious drain on their resources. They were constantly trying to get me removed and annoyed with me and the demands my condition was making on them.19
It can be useful to keep a diary to assist in making sense of events after recovery and to reduce the impact of negative recollections. Similarly, retrospective accounts of patients experiencing delirium during intensive care unit (ICU) stays highlight ward noise, disruptions from other patients and visitors, the sense of isolation, difficulties in communication, restricted movement, and loss of functional integrity as particularly distressing.20 Many patients described their frustration at how staff underestimated their awareness and that in many cases added to the sense of paranoia by discussing the patient without acknowledging their presence.
A range of simple activities can promote delirium awareness: talks from expert clinicians, distribution of written material, posters, and staff emails. Once integrated into staff induction and training these activities need to be repeated on a regular basis in order to encourage discussion and appropriate treatment of cognitive impairment. However, such programmes must be underpinned by operational changes and supports to copper-fasten attitudinal gains. At the core of this issue is the need to recognize delirium as a key condition within healthcare activities and routinely monitor its impact upon outcomes. Educational interventions can assist in delirium prevention and detection in acute hospital and community settings with positive effects in respect of staff attitudes, reduced falls, and medication use.21
Building on a heightened awareness of delirium among all hospital staff, formal training in delirium should be targeted at all clinical and support staff. Different levels and types of education are required for different members of staff, depending on the professional background and clinical profile of patients. For example, the nurse working in the ICU will have a very different profile of patient from the physiotherapist working in the orthopaedic ward. However, a similar foundation in delirium education and training is essential for all healthcare professionals, with some specialization for different individuals, tailored to their particular field. Relevant professional bodies can support the development, approval, and monitoring of initiatives along with the efficiency of delivery. 22
Health service managers need to be aware of the impact of delirium on clinical outcomes and financial costs.6 They can add crucial weight behind programmes that emphasize delirium prevention and treatment. Service planning must ensure the needs of older patients are considered and their impact should be monitored by including delirium as a routine activity measure. It is advocated that all hospital staff should have mandatory training on delirium and cognitive problems in the general hospital, with such training being delivered at the commencement of employment and repeated regularly (e.g. every 6 months). The impact of staff education and training initiatives should also be monitored and evaluated on a regular basis (e.g. through surveys of staff knowledge, attitudes, and clinical practices).
Overall, success of delirium programmes is linked to systems factors that include involvement of clinical leaders, support from senior management, linking the implementation of programmes to periods of systems change, providing educational elements that are sustained and engaging, integrating mechanisms to support decision-making into everyday routines (e.g. electronic care pathways), and monitoring procedures to promote continued adherence. In general, improving delirium care is best achieved where it is supported by activities that promote enthusiasm, support implementation, remove barriers, and allow for progress monitoring.
Risk Factors and Delirium Prevention
A central element of cognitive-friendly services is to minimize exposure to factors that increase the risk of developing delirium. There is good evidence for a range of preventative strategies in reducing delirium occurrence but much less for interventions once delirium becomes established. Resources should thus be directed towards primary preventative measures. The occurrence of delirium reflects the interaction of a range of predisposing patient, illness, and treatment factors with acute precipitating insults to produce a generalized disturbance of brain function. Many of these factors are highly preventable (including many with significant iatrogenic elements)23 such that better service organization can allow for preventative measures to produce better patient outcomes with reduced incidence and duration of delirium when it occurs. In general, interventions that are complex, multifaceted, and focused upon site-specific risk factors are most successful and can reduce the burden of delirium by more than a third.24
The concept of ‘delirium readiness’ has been long recognized. Lindroth and colleagues reviewed 23 different prediction models for delirium that share many recurring factors (severe morbidity, older age, pre-existing dementia, and exposure to opioids, benzodiazepines, or general polypharmacy).25 Baseline risk is especially important as patients with high baseline vulnerability can develop delirium even in response to minor precipitants.
Many risk factors are modifiable while others assist in assessing risk–benefit balance of surgical and other interventions in deciding upon optimal care, especially in frail elderly patients with cognitive impairments (see Figure 19.1). Many of the strategies that are employed in delirium prevention reflect attention to ensuring a high standard of basic medical and nursing care (e.g. avoiding unnecessary polypharmacy, correcting sensory deficits, promoting self-efficacy). However, it has become necessary to protocolize many such practices in order to ensure that they occur consistently in our increasingly chaotic and time-pressurized healthcare environments. As such, improved delirium care with more cognitive-friendly environments is a key target as we embrace the need to provide for an increasingly aged society. In addition, a range of targeted interventions can reduce delirium incidence with gathering evidence for positive impact from interventions that focus upon encouraging physical exercise26 and music therapy.27
