Delirium in Older Adults: Understanding Prevalence

Delirium: A Marker of Vulnerability in Older People

• Delirium is an acute neuropsychiatric syndrome, a common presentation in older adults with acute medical illnesses.
• It can be triggered by one cause but is usually multifactorial, involving a combination of predisposing and precipitating factors.
• This interaction elevates the risk of adverse health outcomes in older adults.
• Pathophysiological mechanisms include neurotransmitter imbalance, neuroinflammation, altered brain metabolism, and impaired neuronal network connectivity.

Epidemiology

• Delirium is prevalent in older patients across diverse healthcare settings.
• A recent meta-analysis of 33 studies indicated a 23% prevalence in medical inpatients.
• The incidence of delirium varies with diagnostic criteria and patient populations but is high, estimating 15-25% after major elective surgeries and 50% after high-risk procedures like hip-fractures and cardiac surgeries.
• Delirium occurrence is significantly higher in ICU patients (31% in a meta-analysis).
• Prevalence in post-acute care, and rehabilitation facilities is 14–18% and in nursing homes, the estimates range from 1.4% to 70%. A recent study of 1454 nursing-home patients reported a 36.8% prevalence.

Causes of Delirium

• Delirium is triggered by a single cause, but often multiple factors interact.
• Predisposing factors include dementia, cognitive impairment, sensory deprivation, dehydration, and severe acute illness.
• Precipitating factors include poor nutrition, use of physical restraints, new medications, urinary catheterization, and various medical procedures.
• Higher the predisposing factor burden, lesser the precipitating factor intensity needed to trigger delirium.

Diagnosis

• Delirium is a clinical diagnosis.
• Confusion Assessment Method (CAM) and CAM-ICU are widely used screening tools.
• CAM-ICU shows 94-100% sensitivity but 89-95% specificity.
• Alternative tests include 4AT, with high sensitivity (76%) and specificity (94%).

Outcomes

• Delirium in older adults is linked to poorer clinical outcomes, including higher mortality risk, increased likelihood of nursing home placement, and cognitive decline.
• The duration of delirium is a strong predictor of poor outcomes, increasing the yearly mortality risk by 2 to 3 times in hospitalized older adults.
• It is also associated with increased risk of developing cognitive impairment and dementia.

Prevention

• Non-pharmacological approaches are generally preferred for delirium prevention.
• These approaches focus on reorientation strategies, hydration, sleep promotion, and pain management.
• Interventions such as the Hospital Elder Life Program (HELP) are effective in reducing delirium incidence and duration.

Treatment

• Pharmacological approaches are generally not recommended as the first-line treatment for delirium prevention.
• If agitation and distress are severe, non-pharmacological approaches fail and there are potential risk factors from medications, antipsychotics might be considered.
• Benzodiazepines may be useful, if delirium caused by alcohol withdrawal or acute seizure, however this is a case-by-case basis.

This quiz explores the critical aspects of delirium as a neuropsychiatric syndrome in older adults. It delves into the epidemiology, risk factors, and pathophysiological mechanisms that contribute to its presentation in various healthcare settings. Gain insights into the prevalence rates and factors that influence delirium in older populations.