Hi, everybody:

On August 25, 2001, I was struck and injured by a car while crossing the street on a crosswalk. The car's bumper hit my left knee; I rolled on the car's hood; I hit the car's windshield, which was pushed in the shape of my head; and I was thrown 40 feet (about 12 meters).

I do not remember anything from this accident. The last thing I remember before being struck by the car is the car being right next to me, ready to hit me. The next thing I remember is "waking up" on the street, in a pool of blood. The bones in my left knee were all broken but, more important, the bones around my right eye were also broken. I was also throwing up blood, even though I did not swallow any.

I would like to know if I can get early Alzheimer's Disease from the concussion on my head. I am a female. I was 26 years old when I had the accident. Now, I am almost 37 years old.

Thanks for your answers.

Don't worry about a future life with Alzheimer's Disease.

A concussion does not cause Alzheimer's Disease. Statistically, people who have suffered "multiple" concussions have a greater likelihood of developing Alzheimer's. Some say it increases the likelihood by a small margin to as much as 18 times more likely.

This statistic is seriously misleading since it does not adjust for those who develop dementia that is not Alzheimer's. There are a number of causes of dementia besides Alzheimer's Disease. The long term damage from multiple concussions can cause non-Alzheimer's dementia.

For example, my father died from dementia that was casually called Alzheimer's Disease. There was never any definitive diagnosis of AD. Just an assumption that since he had dementia, it must be AD. Those of us who followed his 40 year deterioration have observed that his progression was more in line with ischemic dementia (dementia from lack of oxygen to the brain). He suffered from untreated Central Sleep Apnea for those same 40 years.

NFL studies show that multiple concussion and even sub-concussive impacts can cause CTE (Chronic Traumatic Encephalopathy), a shrinking or atrophy of the brain. The symptoms are similar to AD but not the same. The progression is different. So much so that those afflicted have the wherewithal to end their own lives at high ratios. Persons with AD end their own lives at much lower ratios. They lose awareness of their condition before they have a chance to make a life ending decision.

So, if you properly interpret the data, concussion and/or TBI or mTBI is not a direct cause of AD.

I just got back from my brain injury support group meeting. I know many people who have lived decades after their TBI with no increase in symptoms such that would develop over time from AD.

So, don't worry. Just live a life with a few precautions against a future concussions. No risky sports. Wear a helmet when riding a bike or motorcycle.