How long does it take for parkinson's disease to cause you death?

My grandpa has had parkinson's disease for a long time. 5 years ago, he was seemingly healthy, could walk and everything. And now, he cant walk, cant talk good, twicthing alot, and very thin. Im really worried that his time to drawing near. If anyone has had a family member with parkinsons, please let me know everything that happened.

Hi...
My father-in-law has Parkinson's and I cared for him in our home until 3 yrs ago when his condition required more care than we could do at home. He has had this disease for over 20 yrs and is now in a vegetative state in a nursing facility.
Because he was a law enforcement officer, he was always in very good physical shape. This contributed to him being mobile for far longer than anyone ever thought.
Parkinson's is a terminal disease;however people don't die from Parkinson's usually. They die from falls or accidents because of the symptoms of Parkinsons. Like wandering around because of dementia and getting hit by autos. Or falling around the house and breaking a bone which
makes them bedbound much quicker.
Your grandpa needs to take in @2500 calories a day to sustain himself as Parkinson's twitching and involuntary movements burn calories constantly. Virtually impossible to do as they get worse and can no longer eat properly. My father-in-law has had a feeding tube for 2 yrs now. It actually helped him gain back lost weight though he'll never be fat. He is stable now and bedridden,unable to talk, sleeps 75% of the time, unable to move really. The human body is strong though as long as it is receiving nutrition.
There is no telling how long my father in law can hang on in these conditions unless he sustains some sort of infection.
He is coughing a great deal these days as he can no longer control his throat muscles to swallow and chokes on his own saliva. Its very sad to watch and even sadder I'm sure for my husband.
ENJOY your grandpa's time while he is lucid and able to be with you. Thats the only advice I can offer you. And take the gift that this teaches us HOW precious life is and the ability to just put one foot in front of the other.
And I'm sending you a Cyber-hug because this is a suckee suckee disease that is hard on EVERYBODY :~(

Parkinson will not kill the patients. It will go on . it is not time bound for death.

It depends on the person but it can be 10+ years and with medication, diet change, exercise, etc.