12 doctors weighed in:

Why exactly does pneumonia cause dementia like symptoms in geriatric patients?

12 doctors weighed in
Dr. Steven Reidbord
Psychiatry
6 doctors agree

In brief: Fever, hypoxia

As we age, we have less "cognitive reserve".
That is, environmental or mental stressors, sleep deprivation, illness, alcohol, etc impair cognition more than these factors do in young adulthood. Febrile illnesses, eg, pneumonia or bladder infection, are both common and cognitively impairing. Also, pneumonia may temporarily decrease oxygen intake (hypoxia), which also hurts cognitive function.

In brief: Fever, hypoxia

As we age, we have less "cognitive reserve".
That is, environmental or mental stressors, sleep deprivation, illness, alcohol, etc impair cognition more than these factors do in young adulthood. Febrile illnesses, eg, pneumonia or bladder infection, are both common and cognitively impairing. Also, pneumonia may temporarily decrease oxygen intake (hypoxia), which also hurts cognitive function.
Dr. Steven Reidbord
Dr. Steven Reidbord
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3 comments
Dr. William Walsh
In sepsis, there is also worse use of oxygen in the brain (the Mitochondria, which usually use the oxygen to make energy, don't function correctly)...
Dr. Steven Reidbord
Not all pneumonia patients are septic, ie, have a blood infection. When they are, Dr Walsh's point is spot-on.
Dr. Sunil Mehra
Internal Medicine - Pulmonology
4 doctors agree

In brief: Low oxygen ?

Elderly pts mostly present with non pulmonary signs and symptoms like confusion and disorientation and these pts have a poorer prognosis.
It is probably related to sepsis and poor oxygenation in an elderly pt.

In brief: Low oxygen ?

Elderly pts mostly present with non pulmonary signs and symptoms like confusion and disorientation and these pts have a poorer prognosis.
It is probably related to sepsis and poor oxygenation in an elderly pt.
Dr. Sunil Mehra
Dr. Sunil Mehra
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Dr. Susan Uhrich
Psychiatry
2 doctors agree

In brief: Any serious illness

Can cause confusion in any given patient, regardless of age.
When that illness occurs in a patient who may have underlying issues such as circulatory problems, it can happen more often or seem more severe.

In brief: Any serious illness

Can cause confusion in any given patient, regardless of age.
When that illness occurs in a patient who may have underlying issues such as circulatory problems, it can happen more often or seem more severe.
Dr. Susan Uhrich
Dr. Susan Uhrich
Thank
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