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The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 59:M341-M343 (2004)
© 2004 The Gerontological Society of America

EDITORIAL

Delirium: A Call to Improve Current Standards of Care

Joseph H. Flaherty and John E. Morley

Division of Geriatric Medicine, Saint Louis University Health Sciences Center, and Geriatric Research, Education and Clinical Center, St. Louis VA Medical Center, Missouri.

Address correspondence to John E. Morley, MB, BCh, Division of Geriatric Medicine, Saint Louis University School of Medicine, 1402 S. Grand Blvd., M238, St. Louis, MO 63104. E-mail: jgeronmed{at}slu.edu

DELIRIUM is a condition that is poorly recognized, and yet has devastating consequences. Inouye and colleagues (1) found that nurses identified delirium in only 31% of patients in which it was present. Factors present in those whose delirium was not identified included hypoactive delirium, vision impairment, underlying dementia, and being older than 80 years. Overall, delirium is not identified in 32% to 66% of older hospitalized patients (2). A similar high failure to identify delirium has been found in the emergency department (3) and in the intensive care unit (4). Delirium also occurs commonly in subacute facilities and, again, is rarely identified (5). For these reasons, the Confusion Assessment Methodology (CAM) was developed, and has been proven to be useful in detecting delirium (6,7). The CAM for the intensive care unit is useful for this purpose even in ventilated patients (6). The Delirium Rating Score appears to be an equally effective instrument (8). New-onset falls in older persons need to be considered a delirium equivalent (9). Delirium is also often misdiagnosed as depression (10).

While not found in all studies, it appears that delirium results in increased length of hospital stay and increased mortality (11–16). Delirium during hospitalization is highly predictive of future cognitive and functional decline(17–20).

In this issue of the Journal, Bourdel-Marchasson and colleagues (21) provide evidence that delirium is a risk factor for subsequent institutionalization. Kiely and colleagues (22) further stress the importance of this by pointing out that 15% of admitted patients to a post-acute facility are delirious at screening; for many patients, their delirium did not resolve within 1 month of admission. In the study by Bourdel-Marchasson and colleagues (21), falls and poor dietary intake in addition to delirium were associated with institutionalization. This gives credence to the statement above that falls should be considered a delirium equivalent in older persons, and that protein energy malnutrition, which is extremely common in older persons and recognized to be associated with poor outcomes (23–26), is associated with a decline in cognition and can precipitate delirium when the patient is receiving albumin-bound or lipid-soluble drugs. Guidelines for the management of weight loss have been published in the Journal (27).

A number of factors have been found to be predictive of delirium. These include cognitive impairment, advanced age, low albumin level, bone metastases, heart failure, inadequate pain relief and severe pain, meperidine, physical restraints, indwelling urinary catheter, malnutrition, benzodiazepines, stroke, longer duration of cardiopulmonary bypass, and low cardiac output (28–35). In most persons, delirium is multifactorial and its resolution requires a careful recognition and treatment of a number of causes. D-E-L-I-R-I-U-M-S is a mnemonic developed at Saint Louis University to allow a focused approach to the causes of delirium (Table 1).


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  		Table 1. DELIRIUMS Mnemonic for the Treatable Causes of Delirium.

 
The basic mechanisms by which delirium is produced remain uncertain (36). Clearly the circulating level of anticholinergic activity is an important factor (37,38). Many drugs that are not classically thought of as being anticholinergic, such as digoxin, theophylline, and cimetidine, have high anticholinergic activity in vitro. Several other commonly prescribed drugs and over-the-counter medications have been reported to be associated with mental status changes (39). The other major pathogenic factor in delirium appears to be the production of cytokines such as interleukins 1 and 2 and tumor necrosis factor alpha (36,40). These factors have been shown to produce cognitive impairment and to cross the blood–brain barrier (41). In some cases, components of the external core of infectious agents, such as the GP-120 component of the AIDS virus (42), seem to be the causative agent. Poor cerebral blood flow is also associated with the onset of delirium (43).

The prevention of delirium requires a focused interdisciplinary approach as demonstrated by Inouye and colleagues at Yale (44). However, overall, their results could be considered somewhat disappointing, perhaps because of poor compliance with the recommendations (45,46). Similarly, guidelines have failed to produce a major effect on delirium outcomes (47). The development of a Delirium Room at Saint Louis University, which some would consider a delirium intensive care unit because of the 24-hour in-room nursing (however, without the use of any physical restraints), appears to be a successful alternative for the prevention and treatment of delirium. It allows a focus not only on patients at risk for delirium, but patient who already have delirium (39). Part of the success of the Delirium Room is that it is an integral part of an Acute Care of the Elderly Unit, which gives the interdisciplinary team the ability to carry out its own recommendations (48). Further multicenter studies on the efficacy of this model are indicated.

Overall, delirium remains an important and poorly studied area of medicine. Like so many other areas in geriatrics, paying attention to simple common sense measures can reduce the occurrence and improve the management of delirium. Certainly, delirium should be regularly screened for in hospitals and post-acute institutions. Avoidance of drugs with high anticholinergic activity whenever possible is a cornerstone of delirium management. At present, development of delirium intensive care units appears to be a possible cost-effective approach to the management of delirium.

References

  1. Inouye SK, Foreman MD, Mion LC, Katz KH, Cooney LM. Nurses' recognition of delirium and its symptoms—comparison of nurse and researcher ratings. Arch Intern Med.. 2001;161:2467-2473.[Abstract/Free Full Text]
  2. Inouye SK. Delirium in hospitalized older patients: recognition and risk factors. J Geriatr Psychiatr Neurol.. 1998;11:118-125.
  3. Lewis LM, Miller DK, Morley JE, Nork MJ, Lasater LC. Unrecognized delirium in ED geriatric patients. Am J Emerg Med.. 1995;15:142-145.
  4. Ely EW, Inouye SK, Bernard GR, et al. Delirium in mechanically ventilated patients—validity and reliability of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). JAMA.. 2001;286:2703-2710.[Abstract/Free Full Text]
  5. Kiely DK, Bergmann MA, Murphy KM, Jones RN, Orav EJ, Marcantonio ER. Delirium among newly admitted postacute facility patients: prevalence, symptoms, and severity. J Gerontol Med Sci.. 2003;58A:441-445.
  6. Ely EW, Margolin R, Francis J, et al. Evaluation of delirium in critically ill patients: validation of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Crit Care Med.. 2001;29:1370-1379.[Medline]
  7. Pompei P, Foreman M, Cassel CK, Alessi C, Cox D. Detecting delirium among hospitalized older patients. Arch Intern Med.. 1995;155:301-307.[Abstract/Free Full Text]
  8. Rockwood K, Goodman J, Flynn M, Stolee P. Cross-validation of the delirium rating scale in older patients. J Am Geriatr Soc.. 1996;44:839-842.[Medline]
  9. Morley JE. A fall is a major event in the life of an older person. J Gerontol Med Sci.. 2002;57A:M492-M495.
  10. Farrell KR, Ganzini L. Misdiagnosing delirium as depression in medically ill elderly patients. Arch Intern Med.. 1995;155:2459-2464.[Abstract/Free Full Text]
  11. McCusker J, Cole MG, Dendukuri N, Belzile E. Does delirium increase hospital stay? J Am Geriatr Soc.. 2003;51:1539-1546.[Medline]
  12. Cole M, McCusker J, Dendukuri N, Han L. The prognostic significance of subsyndromal delirium in elderly medical inpatients. J Am Geriatr Soc.. 2003;51:754-760.[Medline]
  13. Dolan MM, Hawkes WG, et al. Delirium on hospital admission in aged hip fracture patients: prediction of mortality and 2-year functional outcomes. J Gerontol Med Sci.. 2000;55A:M527-M534.
  14. Rockwood K, Cosway S, Carver D, Jarrett P, Stadnyk K, Fisk J. The risk of dementia and death after delirium. Age Ageing.. 1999;28:551-556.[Abstract/Free Full Text]
  15. Ely EW, Gautam S, Margolin R, et al. The impact of delirium in the intensive care unit on hospital length of stay. Intens Care Med.. 2001;27:1892-1900.[Medline]
  16. McCusker J, Cole M, Abrahamowicz M, Primeau F, Belzile E. Delirium predicts 12-month mortality. Arch Intern Med.. 2002;162:457-463.[Abstract/Free Full Text]
  17. Gruber-Baldini AL, Zummerman S, Morrison RS, et al. Cognitive impairment in hip fracture patients: timing of detection and longitudinal follow-up. J Am Geriatr Soc.. 2003;51:1227-1236.[Medline]
  18. Lundstrom M, Edlund A, Bucht G, Karlsson S, Gustafson Y. Dementia after delirium in patients with femoral neck fractures. J Am Geriatr Soc.. 2003;51:1002-1006.[Medline]
  19. Sands LP, Yaffe K, Covinsky K, et al. Cognitive screening predicts magnitude of functional recovery from admission to 3 months after discharge in hospitalized elders. J Gerontol Med Sci.. 2003;58A:37-45.
  20. McCusker J, Kakuma R, Abrahamowicz M. Predictors of functional decline in hospitalized elderly patients: a systematic review. J Gerontol Med Sci.. 2002;57A:M569-M577.
  21. Bourdel-Marchasson I, Vincent S, Germain C, et al. Delirium symptoms and low dietary intake in older inpatients are independent predictors of institutionalization: a 1-year prospective population-based study. J Gerontol Med Sci.. 2004;59A:350-354.
  22. Kiely DK, Bergmann MA, Jones RN, Murphy KM, Orav EJ, Marcantonio ER. Factors associated with delirium persistence among newly admitted post-acute facility patients. J Gerontol Med Sci.. 2004;59A:344-349.
  23. Liu LJ, Bopp MM, Roberson PK, Sullivan DH. Undernutrition and risk of mortality in elderly patients within 1 year of hospital discharge. J Gerontol Med Sci.. 2002;57A:M741-M746.
  24. Morley JE. A fall is a major event in the life of an older person. J Gerontol Med Sci.. 2002;57A:M492-M495.
  25. Morley JE. Anorexia and weight loss in older persons. J Gerontol Med Sci.. 2003;58:131-137.
  26. Crogan NL, Pasvogel A. The influence of protein-calorie malnutrition on quality of life in nursing homes. J Gerontol Med Sci.. 2003;58A:159-164.
  27. Thomas Dr, Ashmen W, Morley JE, Evans WJ. Nutritional management in long-term care: development of a clinical guideline. J Gerontol Med Sci.. 2000;55A:M725-M734.
  28. Ljubisavljevic V, Kelly B. Risk factors for development of delirium among oncology patients. Gen Hosp Psychiatr.. 2003;25:345-352.[Medline]
  29. Schuurmans MJ, Duursma SA, Shortridge-Baggett LM, Clevers GJ, Pel-Little R. Elderly patients with hip fracture: the risk for delirium. Appl Nurs Res.. 2003;16:75-84.[Medline]
  30. Morrison RS, Magaziner J, Gilbert M, Koval KJ, McLaughlin MA, Orosz G, Strauss E, Siu AL. Relationship between pain and opioid analgesics on the development of delirium following hip fracture. J Gerontol Med Sci.. 2003;58A:76-81.
  31. Foy A, Oconnell D, Henry D, Kelly J, Cocking S, Halliday J. Benzodiazepine use as a cause of cognitive impairment in elderly hospital inpatients. J Gerontol Med Sci.. 1995;50A:M99-M106.
  32. Rolfson DB, McElhaney JE, Rockwood K, et al. Incidence and risk factors for delirium and other adverse outcomes in older adults after coronary artery bypass graft surgery. Canadian J Cardiol.. 1999;15:771-776.
  33. Banks WA, Morley JE. Memories are made of this: recent advances in understanding cognitive impairments and dementia. J Gerontol Med Sci.. 2003;58A:314-321.
  34. Grossberg GT, Desai AK. Management of Alzheimer's disease. J Gerontol Med Sci.. 2003;58A:331-353.
  35. Inouye SK, Charpentier PA. Precipitating factors for delirium in hospitalized elderly persons—predictive model and interrelationship with baseline vulnerability. J Am Med Assoc.. 1996;275:852-857.[Abstract/Free Full Text]
  36. Flacker JM, Lipsitz LA. Neural mechanisms of delirium: current hypothesis and evolving concepts. J Gerontol Biol Sci.. 1999;54A:B239-B246.
  37. Flacker JM, Wei JY. Endogenous anticholinergic substances may exist during acute illness in elderly medical patients. J Gerontol Med Sci.. 2001;56A:M353-M355.
  38. Han L, McCusker J, Cole M, Abrahamoqicz M, Primeau F, Elie M. Use of medications with anticholinergic effect predicts clinical severity of delirium symptoms in older medical inpatients. Arch Intern Med.. 2001;161:1099-1105.[Abstract/Free Full Text]
  39. Flaherty JH. Commonly prescribed and over the counter medications. Causes of confusion. Clin Geriatr Med.. 1998;14:101-127.[Medline]
  40. Holmes C, El-Okl M, Williams AL, Cunningham C, Wilcockson D, Perry VH. Systemic infection, interleukin 1 beta, and cognitive decline in Alzheimer's disease. J Neurol Neurosurg Psychiatr.. 2003;74:788-789.[Abstract/Free Full Text]
  41. Banks WA, Farr SA, La Scola ME, Morley JE. Intravenous human interleukin-1 alpha impairs memory processing in mice: dependence on blood-brain barrier transport into posterior division of the septum. J Pharmacol Exp Ther.. 2001;299:536-541.[Abstract/Free Full Text]
  42. Farr SA, Banks WA, Uezu K, Freed EO, Kumar VB, Morley JE. Mechanisms of HIV type 1-induced cognitive impairment: evidence for hippocampal cholinergic involvement with overstimulation of the VIPergic system by the viral coat protein core. AIDS Res Hum Retrovir.. 2002;18:1189-1195.[Medline]
  43. Yokota H, Ogawa S, Kurokawa A, Yamamoto Y. Regional cerebral blood flow in delirium patients. Psychiatr Clin Neurosci.. 2003;57A:337-339.
  44. Inouye SK, Bogardus ST, Charpentier PA, et al. A multicomponent intervention to prevent delirium in hospitalized older patients. N Engl J Med.. 1999;340:669-676.[Abstract/Free Full Text]
  45. Inouye SK, Bogardus ST, Williams CS, Leo-Summers L, Agostini JV. The role of adherence on the effectiveness of nonpharmacologic interventions—evidence from the delirium prevention trial. Arch Intern Med.. 2003;163:958-964.[Abstract/Free Full Text]
  46. Bogardus ST, Desai MA, Williams CS, Leo-Summers L, Acampora D, Inouye SK. The effects of a targeted multicomponent delirium intervention on postdischarge outcomes for hospitalized older adults. Am J Med.. 2003;114:383-390.[Medline]
  47. Young LJ, George J. Do guidelines improve the process and outcomes of care in delirium? Age Ageing.. 2003;32:525-528.[Abstract/Free Full Text]
  48. Flaherty JH, Tariq SH, Raghavan S, Bakchi S, Moinuddin A, Morley JE. A model for managing delirious older inpatients. J Am Geriatr Soc.. 2003;51:1031-1035.[Medline]




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