MENTAL STATUS CHANGES

LEARNING OBJECTIVES :

KNOWLEDGE - Students should be able to define or describe:

  1. Mental status changes and the syndromes of dementia and delirium (acute confusional state) as well as psychiatric illnesses that may present as changes in mental status.
  2. The major points of differentiation between dementia, delirium, and depression on history, physical examination, and mental status testing.
  3. The differential diagnosis for dementia, the major causes of dementing illnesses, and the work-up for dementia.
  4. The major causes for delirium (acute confusional states) and the diagnostic evaluation of the delirious patient.
  5. How to speak with the patient and/or the patient's family regarding diagnosis, care plans, and prognosis.   In the primary care of a person with dementia, this would include discussion of advance directives and durable power of attorney, planning for care at home or in another setting, and discussion of care in the event of a serious illness.
  6. That mental status changes are a common pathway of a variety of illnesses in older patients and that older people should not be assumed to be demented when they present with mental status changes.
  7. That mental status changes are a common event in the care of patients with HIV related illness.

 

SKILLS - Students should be able to:

  1. Recognize altered mental status in a patient.
  2. Gather a history from a patient or other informants that helps to differentiate between dementia, delirium, or a psychiatric illness.
  3. Focus questions in the history that will elucidate the underlying etiology of the mental status change.
  4. Perform a thorough physical examination with emphasis on the neurological evaluation that assists in the diagnosis of mental status changes
  5. Do a screening mental status examination using the Folstein Mini-Mental State Exam and be able to interpret the results.
  6. Recognize that the differential diagnosis of a person with mental status changes includes a delirium, a dementing illness, and a psychiatric illness such as depression, mania, or psychosis.   In considering the diagnosis of dementia, one must further differentiate between a dementia of the Alzheimer's type, vascular dementias (including multi-infarct dementia), other less common causes of dementia, and the reversible dementias (hypothyroidism, prolonged drug intoxication, vitamin B12 deficiency, chronic subtotal hematoma, etc.).   For persons with acute confusional states/delirium, the differential centers on the underlying etiology and can be roughly divided into neurologic causes (trauma, stroke, seizure, infection), systemic causes, and psychiatric illness.   In individuals with HIV infection, mental status changes can have a long differential and include the AIDS dementia complex, another infectious process (e.g. Toxoplasmosis), a neoplastic process (e.g., CNS lymphoma), or any of the other reasons why an individual may have mental status changes.
  7. Order and interpret the following laboratory examinations in the evaluation of a person with mental status changes:   CBC, electrolytes, glucose, BUN, creatinine, liver function tests, thyroid function tests, calcium, phosphorus, vitamin B12, VDRL, drug screen, arterial blood gases, lumbar puncture, CT scan, MRI scan, EEG.
  8. As necessary, perform a venipuncture for laboratory testing and, in selected cases, a lumbar puncture.

 

ATTITUDES AND PROFESSIONAL BEHAVIORS:

  1. Recognize the anxiety and concern of patients and their families with mental status changes and be able to provide empathic care with accurate information, appropriate support, and on-going care.
  2. An awareness that delirious and demented individuals are to be treated with respect, concern and compassion.
  3. Willingness to assist and discuss care issues with the family of persons caring for individuals with dementing illnesses.

A brief word about terminology.   The topic of mental status changes can be made more complicated than it need be by confusing terminology.   Delirium and acute confusional states are used interchangeably by many physicians.   Others reserve the term delirium for a person who is confused and agitated, the classic example would be delirium tremens.   Another point of confusion concerns the use of the terms delirium, dementia, and reversible dementia.   A delirium is normally considered reversible.   Dementias are, in general, irreversible.   So what is a reversible dementia?   It is a dementing illness which, if the etiology is determined and appropriate treatment instituted, the signs and symptoms of the dementia will be reversed or lessened and the person will improve

 

RECOMMENDED READINGS :

  1. Isselbacher KJ, Braunwald E, Wilson JD, et al (eds.):   Harrison's Principles of Internal Medicine
  2. Siu AL.   Screening for dementia and investigating its causes.   Annals of Internal Medicine.   1991;115:122-132. (A good reference regarding cost-effective approaches in the work-up of dementia)
  3. Malaz Boustani, Britt Peterson, Laura Hanson, Russell Harris, and Kathleen N. Lohr
    ” Screening for Dementia in Primary Care: A Summary of the Evidence for the U.S. Preventive Services Task Force”    Ann Intern Med , Jun 2003; 138: 927 - 937.
  4. Christopher M. Clark and Jason H.T. Karlawish   “ Alzheimer Disease: Current Concepts and Emerging Diagnostic and Therapeutic Strategies”    Ann Intern Med , Mar 2003; 138: 400 - 410.