How does Parkinson's cause death? - (Sep/23/2006 )
I saw Strawberry's question about cancer and death, and was wondering the same thing about neurodegenerative diseases...does anyone know how Parkinson's, Alzheimer's, Huntington's, etc. actually cause death? On the news you hear "died of complications related to Alzheimers" but what does that mean?
i'm sure that in alzeihmer, there is protein precipitation agregation and finally lysis of the neuron.
In parkinson, not sure about the mechanism, but affects also the nerve cells.
so i guess when you reach a critical number of neuronal connections or loose the importan one, it's a negative way.
There r many different factors involved in neuronal death leading to neurodegenration.
For eg. in parkinson's disease, one finds the substantia nigra - region of the midbrain- neurons primarily affected. Once the number of cells falls below a particular threshold the patient would show symptoms.
What happens in these neurons is not exactly know. But hypothesis suggests abnormal protien degradation or over production, leading to aggregation which could block internal transport within the cell. If mitochondria is not transported, no energy is produced for the neuron which it needs. So this would cause collapse of the entire cellular fucntion.
This is not the only thing that happens. Other brain regions r also affected. Genetics show 4-5 protiens which might all b involved in these patients. Interestingly, other neurodegenerative patients might also have similar pathology. So is there a overlap of these diseases. There is evidence for overlap of many of these diseases.
If u read that a ptient died due to complications of a disease, it could b like neurons r affected and different affected regions would lead to dif. symptoms.
this is just an eg. a patient might have midbrain lesions, then gradually progressing, it might affect the respiratory centers leading to respiratory collapse.
I don't think that in those patients neuronal degeneration actually comes to a point at which it would be really able to cause death. This would mean that it would have to affect the brain stem (respiratory center and so on)...
I rather think that those patients have lowered life expectancy not because they have this disease, but because they are not healthy (sounds weird, but let me explain.....)
They are pumped up with medication, which can cause damage itself (image dopamine in case of PD patients, it can cause serious heart problems). Their system has to deal with all those stuff, their stomachs have to tolerate it, their livers have to clear it from the system. Then bone and muscle degeneration because parkinson's is a movement disorder and lack of training is a problem.
PD itself e.g. would not cause death. Patients can live quite ...ehm "well" with it for 20 years (seen it myself...). Its just all what comes along with it which tends to kill the patient, I think.
I hope this is helpful,
Parkinsonian patients often die due to aspiration pneumonia, if I remember correctly. The loss of fine muscle control leads to difficulty in maintaining the normal measures our bodies have for separating air and food/water once they enter the mouth. Some might remember how John Paul II needed to be intubated once he wasn't doing very well - that seems to be one of the few preventive measures that can be taken to treat late-stage Parkinsonism.
edit: Here's a reference:
Mov Disord. 2003 Nov;18(11):1312-6
Thanks for all the insight. I actually am involved with PD research, so I understand the dopaminergic neuronal degeneration from a molecular standpoint, but that simple question has always bothered me!
thinking more abt ur question,
I realised that even AIDS doesnt kill anyone directly but that AIDS related diseases (complications of AIDS) which cause the death.