Confused Elderly Patient 09/29/2000 Nakahara
Initial Approach
Yet not all cognitive problems in the elderly are due to dementia.
Only after delirium and psychiatric disorders have been ruled out can dementia be diagnosed in an elderly patient with cognitive impairment. Because delirium is associated with an increased risk in mortality, it should always be considered first when a physician confronts a patient with cognitive impairment.
DDD（Delirium, Depression, Dementia）を鑑別する。
Delirium
認知の変化を伴う意識障害（注意を集中・維持する能力の低下。短期間で出現し、変動がある。
チューブや点滴を取ろうとするなどのagitationや、活動減少 型（日中うとうと）がある。短期記憶や見当識も傷害される。環境変化（入院当日や術後）、ストレスなどがリスクになる！
Common Causes of Delirium
Metabolic disorders
Electrolyte abnormalities
Acid-base disturbances
Hypoxia
Hypercarbia
Hypoglycemia or hyperglycemia
Azotemia
Infections
Decreased cardiac output
Dehydration
Acute blood loss
Acute myocardial infarction
Congestive heart failure
Stroke (small cortical)
Medications
Intoxication (alcohol and/or other substances)
Hypothermia or hyperthermia
Acute psychoses
Transfer to unfamiliar surroundings
Miscellaneous
Fecal impaction
Urinary retention
Risk R/O Electrolyte, Dehydration, Infection
Urinary retention.
Drug（全ての。NSAIDやH2-Blockerでも）
Dementia
Hearing or Visual disorder
Delirium and dementia may coexist. Dementia is a known risk factor for delirium. As many as 22 percent of community-dwelling elderly persons with dementia have coexisting delirium. At any one time, 15 percent of hospitalized patients over the age of 70 years are delirious. In this situation, treatment of the delirium often improves the patient's cognitive and/or functional abilities
Depression
Check DSM-Ⅳ Criteria
2wk depressed mood+5/8 “SIGECAPS”
Dementia
Memory impairment and at least one of the following:
Aphasia
Apraxia
Agnosia
Impaired executive functioning (e.g., planning, organizing, abstracting)
Significant impairment in social functioning.（これも必須項目）
Significant decline from previous level of functioning
Deficits that do not occur exclusively during the course of delirium
・Memory impairment
生理的物忘れとは違う。痴呆による物忘れは、体験した全体が抜け落ち自覚が無く高度で進行性である。日常生活に支障を及ぼす。
（例）最近よく人の名前を忘れたり、物を置き忘れたりするが実生活に支障は無い。
→老化による生理的物忘れ
体験の一部を思い出せない。後になって思い出す。物忘れを自覚している。生活に支障が無い
・Aphasia
Have any difficulties with finding the right word to say?
Substitute an incorrect word, such as "chair" for "table"?
Break off in midsentence or lose his or her train of thought?
Stutter or repeat words over and over?
・Apraxia
Dressing or bathing alone?
Using a brush or comb?
Feeding himself or herself?
If the answer to any of the above is yes, follow up with: Do you think it's a physical
problem, or is it because he or she is having trouble figuring out how to do it?
・Agnosia
Familiar people or places?
Familiar objects or personal items?
Mental Status Examination
The Mini-Mental State Examination (MMSE) is the most widely used method for grading cognitive status. A score of less than 24 is considered abnormal, but this score should be adjusted to account for the educational bias associated with the instrument. An abnormal score on the MMSE is not diagnostic of dementia or delirium, but it does reflect the severity of cognitive impairment.
スクリーニングとして有用だが、病歴や問診にもとづく患者の全体像を無視して痴呆の有無を判断しない。検査を受けている患者の態度としては、あっけらかんととして他人事のようであり,でまかせな応答をするのがアルツハイマー病らしさである。悲壮感があったり，回答に時間がかかるのは脳血管性痴呆、うつ病の方が多い。
Medication Review
Polypharmacy and adverse drug reactions are major causes of confusion in the elderly. Since many commonly used drugs can cause delirium.
（例）一ヶ月くらい前から物忘れがひどくてボーっとしている。転倒歴はない。CTでは異常ないといわれた
内科と整形外科に通っている。お薬は10種類以上飲んでいます。
→慢性薬物中毒。
精神安定剤や、抗うつ剤、睡眠薬などに注意。複数の医療機関を受診している場合にはレビューを忘れない。
Medications Associated with Confusion in the Elderly
Analgesics
(narcotic and nonnarcotic)
Antihistamines
Antihypertensives
Antimicrobials
Antiparkinsonian drugs
Cardiovascular drugs
Hypoglycemics
Psychotropic drugs
Anxiolytics
Antidepressants
Antipsychotics
Hypnotics
Miscellaneous
Cimetidine (Tagamet)
Steroids
Xanthines
History
患者および家族（または親しい友人）の両方からの病歴聴取が必要となる。認知障害が最初に現れた時期、病初期の行動異常を正確に把握する。階段状の進行は脳血管性痴呆に特徴的だが、アルツハイマー型痴呆でも身体合併症（肺炎、骨折etc）により急激な変化が階段状に見えることもある。
身体的病歴を見直す→認知障害の症候に関与する外科手術（胃切除術など）、内科疾患（高血圧やSLE）、輸血歴、重金属曝露、頭部外傷歴。アルコールや薬物、市販薬など。
Physical Examination
the physician should focus the physical examination on the cardiovascular, neurologic and psychiatric systems. Note that the physical examination is frequently normal in patients with early DAT.
The physical evaluation should include an assessment of the patient's level of arousal and orientation. Patients who lack alertness or have a clouded consciousness are more likely to have delirium than dementia. Focal neurologic changes are signs of an underlying neurologic disorder. Unfortunately, focal changes are not associated exclusively with delirium or dementia.
Treatable Dementia
Dementia can be classified as reversible or irreversible. Potentially reversible causes include thyroid dysfunction, deficiencies of vitamins such as B12 and folate, infections such as neurosyphilis, metabolic abnormalities such as uremia, and normal-pressure hydrocephalus.
(例)3週間前より元気がなく失禁がみられる。一ヶ月前に玄関で転んだ。もともと大酒のみ→慢性硬膜下血腫
(例)記銘力の低下、見当識障害、妄想あり。TSH高値→甲状腺機能低下の仮性痴呆。甲状腺製剤で消失。
Laboratory Tests
Test Possible underlying causes that can be detected
Urinalysis Urinary tract infection, diabetes
Electrolytes Electrolyte imbalance
Serum, calcium Hypercalcemia, hypocalcemia
BUN, creatinine Uremia
Liver enzymes Hepatic dysfunction, encephalopathy
Thyroid hormones Hyperthyroidism, hypothyroidism
Serum B12 VB12 deficiency
VDRL Neurosyphilis
CBC, Chemi, Renal/Liver, TSH, B12(Folate), VDRL
Electroencephalograms (EEGs)
can be used to detect patterns characteristic of delirium, especially when a previous EEG is available for comparison. Electroencephalograms (EEGs) in patients with Alzheimer's disease may be normal or show diffuse slowing and are not obtained in the routine evaluation of dementia. However, an EEG may be helpful when seizure or Creutzfeldt-Jakob disease is suspected (in the latter, an EEG shows both diffuse slowing and periodic complexes).
Lumbar puncture
is not needed in the evaluation of most patients with dementia. However, spinal fluid examination may be indicated in those with specific clinical and laboratory findings
Acute or subacute onset (<8 wk)
Evidence of immunosuppression
Fever or presence of meningeal signs
Atypical presentation of dementia (eg, severe headaches, seizures, cranial neuropathies)
Clinical findings suggestive of normal-pressure hydrocephalus
Positive serum fluorescent treponemal antibody absorption test
Abnormalities on computed tomographic or magnetic resonance imaging brain scan (eg, meningeal enhancement)
Diagnostic imaging
Computed tomography (CT) or magnetic resonance imaging (MRI) of the brain has become a routine part of the workup of suspected dementia. Yet the value of these expensive tests in the evaluation of dementia continues to be questioned. In actual practice, both families and physicians often are not satisfied that a "thorough" workup has been done unless an imaging test has been performed. However, CT or MRI should not be considered a substitute for thorough history taking and physical examination.
As a general rule, imaging should be performed in most patients with dementia. However, it may not be warranted in patients in whom the medical history reveals no significant findings, the results of physical and neurologic examination are normal, and the onset and progression of cognitive decline are consistent with Alzheimer's disease. Imaging may be helpful in diagnosis of atypical dementias, meningitis, hydrocephalus, tumor, stroke, focal lesions or atrophy, and hematomas. CT or MRI is particularly recommended in patients with an atypical presentation, rapid deterioration, incontinence, focal neurologic signs, past history of head injury, or systemic diseases that prominently affect the brain (eg, HIV infection, systemic lupus erythematosus).
Apolipoprotein E
the recommendation is that apo E genotyping should be limited to use in patients with cognitive deficits who are members of autosomal-dominant families with a history of early-onset DAT
MGH総合病院精神医学マニュアル
Diagnostic Approach to the Confused Elderly Patient - March 15, 1998 - American Academy of Family Physicians
Initial evaluation of suspected dementia: asking the right questions. Postgrad Med 1999:106(5):72-83
最終更新：2006年08月26日 09:44
