Re: life span question
Post by Bobbie » Fri May 14, 2010 6:43 am
That's not really an easy question to answer.
Overall, life expectancy goes down for paraplegics, human or animal, because when you average them all together you include the ones who have recurrent UTIs or pressure sores, either of which can be fatal as they can lead to widespread infection or systemic organ failure.
Here is some info about people:
WHAT IS THE LIFE EXPECTANCY OF PEOPLE WITH PARAPLEGIA?
Life expectancy is the average remaining years of life for an individual. It refers to how much longer someone is expected lo live. Life expectancy for people with paraplegia is lower than normal, but has continued to increase over the years. Death rates are significantly higher during the first years after the injury than the later years. This is especially true as the severity of the injury increases. Also, younger people with paraplegia have longer life expectancies than older people with paraplegia.
The following are average life expectancies for people who have survived a spinal cord injury after 24 hours. It is important to remember that these averages represent group data and cannot be applied to a specific individual. For people who develop paraplegia at age 20, the average life expectancy is 45 years (meaning they will live, on averae, for 45 more years). By comparison, people at age 20 with no spinal cord injury have an average life expectancy of 57 years. For people who develop paraplegia at age 40, the average life expectancy is 28 years. People at age 40 with no spinal cord injury have an average life expectancy of 38 years. For people who develop paraplegia at age 60, the average life expectancy is 13 years. People at age 60 with no spinal cord injury have an average life expectancy of 21 years.
How to translate that to dogs, assuming it would be similar? A dog injured at 4 is like a person injured at about age 30. At that point life expectancy would be about 37 years, or something more than twice their current age, but about 75% as long as a non-paraplegic. So if your breed has a normal average life expectancy of 12 years, the average with paraplegia onset at 4 would be about 9 years.
HOWEVER...it also states that death rates are higher sooner after the injury. That is, the longer the person survives with paraplegia, the higher her life expectancy goes. So Candy, injured at 4, but already 10 and still perfectly healthy, probably now has a close to normal life expectancy, compared to other 10 year old corgis.
Also, I doubt some of the things that decrease life expectancy in humans even affect dogs. Humans are at higher risk for pulmonary embolism (blood clots in the legs.) I don't know if dogs even get this, but a very active dog like Candy would be at lower risk for it. Another cause of death in humans is autonomic dysreflexia, which is when the nervous system basically freaks out due to some stimulus below the injury level, such as an overfull bladder. This is most common with an injury above T5 or with quadriplegia. T5 is at the level of chest muscles. Autonomic dysreflexia has been demonstrated in animal models but I doubt it has been identified clinically.
So, to make a long answer short, the longer your dog lives problem-free with a spinal cord injury, the longer she is likely to live. Keeping her active and avoiding UTI's and other infections will probably help. Candy, as I said, is now 10, six years plus post injury, and in the peak of health, and I doubt his life expectancy is anything below normal any more.
I would like to follow up this very interesting question when I have more time, and see what the research on animal models does say. I know of canine paraplegics who have died from multiple organ failure after recurrent UTIs, but I don't know how many have lived long, normal lives.