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JoukoLaurila

Delirium in the Elderly

Essentials

  • Delirium or acute confusional state is an extensive, rapid-onset disturbance of brain function due to an organic cause.
  • Delirium is difficult to recognize (more than half of the cases remain unrecognized) and the prognosis is poor.
  • Delirium increases the incidence of complications and mortality during hospitalization.

Prevalence and prognosis

  • Delirium occurs in 10-40% of the elderly during hospital care. Physicians recognize only one third of the cases.
  • The patient may recover even from a delirium that has endured for several weeks.
  • Mortality is up to 25%, and among the oldest of the elderly, up to 40% end up in institutional care.

Symptoms

  • Delirium is manifested by impairment of attention and apperception (attention deficit) and disorganized logical thinking. Consciousness becomes clouded and cognitive functions are suddenly deteriorated. The state is often associated with hallucinations and aberrant thoughts, disorders of the sleep-wake schedule, alteration of psychomotor activity, disorientation, impairment of memory and fluctuations of mood.
  • Clinical features develop over a short period of time and tend to fluctuate over the course of the day.

Predisposing factors

  • Advanced age
  • Degenerative brain diseases (especially memory diseases)
  • Severe somatic illnesses (e.g. cancer)
  • Polypharmacy (especially anticholinergic drugs and opioids)
  • Impairment of vision and hearing, sleeplessness, unfamiliar environment, physical restraints
  • Surgery

Triggering factors

  • A variety of underlying conditions can cause delirium.
  • Medications
    • Drugs with anticholinergic properties (tricyclic antidepressants, phenothiazines, hydroxyzine, biperidine)
    • Opioids, sedatives, levodopa, lithium, bromocriptine, steroids, many antimicrobials (such as quinolones and clindamycin)
    • Abrupt discontinuation of a regularly used anxiolytic or of alcohol use (delirium tremens, see also Treatment of Alcohol Withdrawal)
  • Infections
    • Pyelonephritis, pneumonia, sepsis, erysipelas, meningitis, febrile viral infections
  • Cardiovascular diseases
    • Myocardial infarction, arrhythmias, pulmonary embolism, hypotension, etc.
  • Cerebrovascular diseases
    • Cerebral infarction, TIA, cerebral haemorrhage, subarachnoid haemorrhage
  • Metabolic and endocrinological disorders
    • Disorders in acid-base balance, disorders in fluid and electrolyte balance, hypoalbuminaemia, hypophosphataemia, insufficiency of the liver, kidneys or lungs, hypo- or hyperglycaemia, hypo- or hyperthyroidism, disorders of calcium balance, deficiencies of different B-vitamins, anaemia, other endocrinological disorders, etc.
  • Others
    • Traumas (head injury, subdural haematoma, burns, hip fracture, surgery, etc.)
    • Epilepsy, postictal state
    • Tumours (intracerebral, pulmonary), myeloma
    • Poisoning (e.g. digitalis intoxication)
    • Extensive life stress (especially in patients with memory disease)

Diagnosis

  • History: When was the patient last well? Course of symptoms? Cognition before the illness? Usage of medications? Usage of alcohol?
  • Careful physical examination
  • CRP, basic blood count with platelet count, plasma sodium, potassium, creatinine, blood glucose, ECG
  • As needed: chemical urinalysis, TnT, ESR, glytamyl transferase, alkaline phosphatase, TSH, free T4, ionized calcium, vitamin B12, erythrocyte folate and arterial blood gas analysis, etc.
  • Chest x-ray
  • Analysis of cerebrospinal fluid, head CT scan, full body CT scan, EEG when needed
  • Further tests when needed, aiming at identifying aforementioned aetiological factors. Underlying causal factors are found in almost all cases when investigated carefully. Delirium in an elderly patient is often multicausal.

Differential diagnosis

  • Memory disease
    • Insidious onset and slow course, usually with no daily variation in the intensity of symptoms
    • Level of consciousness is normal, and attention intact until late stages
  • Psychotic disorders
    • Level of consciousness is normal, cognitive functions are not globally disturbed. Speech is not totally disorganized. Also the psychiatric patient history is differrent.
    • Auditory hallucinations are common in psychosis, whereas visual hallucinations are more common in delirium.
  • Dementia and delirium are often seen in same patient.
  • The Confusion Assessment Method (CAM) is a good differential diagnostic tool (see e.g. http://help.agscocare.org/productAbstract/H00101)http://www.dynamed.com/condition/delirium-in-hospitalized-patients#TOOLS_FOR_DIAGNOSING_DELIRIUM_IN_HOSPITALIZED_PATIENTS. It is easy to use and has been validated in a number of different patient groups.

Management Droperidol for Psychosis-Induced Aggression or Agitation

Prevention

    References

    • Oh ES, Fong TG, Hshieh TT ym. Delirium in older persons: advances in diagnosis and treatment. JAMA 2017;318(12):1161-1174. [PubMed]
    • Nikooie R, Neufeld KJ, Oh ES ym. Antipsychotics for treating delirium in hospitalized adults: a systematic review. Ann Intern Med 2019;171(7):485-495. [PubMed]
    • Shenvi C, Kennedy M, Austin CA ym. Managing delirium and agitation in the older emergency department patient: the ADEPT Tool. Ann Emerg Med 2020;75(2):136-145. [PubMed]
    • Hshieh TT, Yue J, Oh E ym. Effectiveness of multicomponent nonpharmacological delirium interventions: a meta-analysis. JAMA Intern Med 2015;175(4):512-20. [PubMed]