Prognosis and Outcome
Besides increasing the likelihood of death, delirium is associated with extended hospital stays due to ongoing psychiatric symptoms or functional decline (O’Keefe 1997a). A delirious person is far less able to consistently manage activities of daily living as the course of symptoms fluctuates throughout the day. The change in cognitive function makes meeting basic needs such as feeding, toileting, and washing difficult, if not impossible, to accomplish independently. The sequelae of immobilization include:
- decubitus ulcers (bed sores)
- deep vein thrombosis
- poor nutrition
- use of instrumentation, such as urinary catheters or intravenous lines
These can further precipitate or perpetuate the delirious state. Ongoing delirium can interfere with the person’s participation in therapy and rehabilitation. Permanent changes in these areas can result in the person requiring continuing care or long term care placement. This is costly to the health care system but can also be a financial burden for the individual or their caregivers.
A delirious person may delay timely management of an acute treatable illness due to changes in cognitive function, paranoia, or behaviour, so a competency assessment may be necessary in order to evaluate their ability to understand or appreciate the nature of the treatment(s) proposed (APA Practice Guideline, 1999). This consent process is outlined by the Health Care Consent Legislation of BC (Public Trustee 2000). The attending team should consider the impact of treatment, or the lack thereof, on both survival and quality of life, and in some cases consider a time-limited intervention in situations where treatment may lead to uncertain benefits (eg: tube feeding). One may need to consider involuntary detainment in hospital in order to treat the delirious person who is wishing and able to discharge oneself against medical advice.
Non-pharmacologic interventional research trials, such as interpersonal contact and environmental manipulation, for delirium have shown only some modest beneficial effects in improving outcome (APA Practice Guideline 1999). Early detection and prevention controlled studies have also generally noted only modest benefits in the delirious senior (Cole 2004). Nevertheless, educating the patient and family about delirium and its aftermath is worthwhile.
Agitated and combative delirious persons are at risk for injuring themselves and the staff caring for them, and hence the rational use of psychotropics can be indicated as long as the underlying cause(s) is addressed. However, passivity or somnolence due to over-treatment with these agents, or hypoactivity due to apathetic delirium, may also result in enhanced morbidity from functional decline.
Delirious states can last for weeks or even months if unrecognized and left untreated, so those afflicted may be discharged home or to long-term care facilities unknowingly. This is especially tragic considering most causes of delirium respond to treatment once identified. When the cause of the delirium is identified however, and if treatment is optimized, the delirious person can return to baseline over a period of days to months. Typically, the symptoms of delirium resolve within 10-12 days, but up to 15% have symptoms persisting beyond 30 days (APA Practice Guidelines 1999). For those seniors with several risk factors, or risk factors that are deemed major contributors to delirium such as pre-existing dementia, recovery to baseline is still possible but with an increase in the likelihood of residual problems in function or cognition (Rockwood 1999; McCusker 2001, Cole 2009). Delirium occurring in those without pre-existing dementia may be a marker for developing dementia later in some seniors, so further community monitoring is warranted even after the delirium resolves (Rockwood 1999).