Some Thoughts on Cholesterol: Man vs. Beast
It’s another snow day here in the Dallas area, so many local schools and businesses are closed. Yah, yah, this is like a balmy summer day to those from colder climates, but for us, this is a big deal.
Sure it snows here from time to time, but it rarely sticks to the roads, and if it does, it’s never for more than a day. They don’t salt the roads ‘round here, so we either have to brave the slipperiness or stay home.
I was actually pretty impressed that they were able to wrangle up some snow plows to clear the roads to the all important Super Bowl XLV a couple of weeks ago. I think they imported them from Oklahoma. We Texans do want to be good hosts.
So, on to today's topic: cholesterol — human vs. animal.
I secretly love human medicine and finding parallels between human and veterinary medicine. Any MDs out there, feel free to jump in and help me out on this one.
My husband’s cholesterol recently jumped through the roof. We’re both 37, so not old, but you know: 40 is looming ever closer (even closer for me, as I turn 38 next month, while hubby has another six months to go). We are not in the habit of watching things like cholesterol because that is an "old person thing." (Of course, I’m being tongue-in-cheek!)
I might mention that my cholesterol is hunky-dory. It’s high, but it’s mostly HDL, the good stuff, so my veins are happy-happy.
Not so for the hubby. This set me (as it probably does most of you) onto Dr. Google to learn more about his condition (and to see if I can draw any veterinary parallels).
We don’t worry about cholesterol much in the vet biz. Dogs and cats don’t really get arteriosclerosis and have heart attacks per se. We certainly don’t break cholesterol up into HDL and LDL (which in my brain has been translated into: "H" for "happy" fat and "L" for "lousy/lethargic/looser/lame" fat).
Dog and cat blood panels just give me a total cholesterol number and a triglyceride number.
Off the top of my head, on those rare instances when a dog’s cholesterol is elevated I consider:
a. Is it a Schnauzer? They have breed related lipid issues
b. Did the dog eat within eight hours prior to the blood test? This will falsely elevate blood lipid (fat) levels
c. Does the dog have hypothyroidism? Low thyroid levels raise blood lipid levels
d. Is s/he diabetic? Have Cushing’s disease? High fat diet, Or other medical reason for it?
e. I don’t necessarily jump to the "is he eating too much chicken-fried steak?" conclusion right off the bat.
Hyperlipidemia is less common in cats, but I do see it in some diabetics. Apparently it can be hereditary in some Himalayan cats.
I did see one cat years ago who came in because his eyes had turned white. Like freaky, zombie white. His blood lipid levels were through the roof. Turned out he had hereditary hyperchylomicronemia (I got to do this cool test where we put his fatty blood serum in the fridge and the "cream" floated to the top to confirm it.) His serum, which is supposed to be the clear part of his blood, was white as whole milk (and his collar had cows on it — we always got a kick out of that).
Anyhow, the cat was managed beautifully on niacin and fish oil. (Although I’m currently looking at the book article on hyperlipidemia and it says that niacin is no longer recommended for dogs and cats … go figure.)
There is a laundry list of other obscure conditions that cause high fat levels in dogs and cats. Yet, when I look at The Book (which is Blackwell’s 5 Minute Veterinary Consult, my favorite reference book because it boils all diseases down to "just the facts ma’am" in two pages or less), it says that "checking cholesterol often is not necessary because hypercholesterolemia is not associated with clinical signs."
Ha … I’m doing a VIN search on hypercholesterolemia and an article came up entitled: Dietary and Surgical Management of Lipid Keratopathy and Systemic Hyperlipidemia in Captive Moray Eels. How’d you like to be the guy doing the cholesterol check blood draw on that one? Where do you put the tourniquet?
So Dr. Google says that hyperlipidemia/hypercholesterolemia in humans leads to atherosclerosis, heart disease, high blood pressure, stroke etc.
Things we just don’t see much of in pets. Again, off the top of my head: high blood fat levels, especially in dogs, can commonly cause pancreatitis. Really high fat levels can cause seizures in dogs and cats.
They don’t seem to clog up their arteries and hearts, though.
I wonder why? What makes them different?
I read a hypothesis by someone who said it’s because dogs and cats don’t live as long as people. Pets will die of other human diseases: congestive heart failure, diabetes, cancer, kidney disease, etc., but not usually heart attack or stroke.
Is it the pet's diet? Stress-free living? Something inherent in being a dog or cat?
Has anyone on the human side wondered why? Should they?
Dr. Vivian Cardoso-Carroll