Life Lines

Heart disease in chimpanzees

chimpanzee monitor.jpg
Image: Jill Moyse (left) and Maureen Leahy (right) monitoring Keo, a 54-year-old chimpanzee in the Lincoln Park Zoo. (AP Photo/M. Spencer Green)

Dr. Kathryn Gamble, the chief veterinarian at the Lincoln Park Zoo in Chicago, has been studying heart disease in captive chimpanzees. Over one third of deaths in these animals are related to heart disease despite healthy diets, exercise and regular testing. Her team has implanted heart monitors in eight of the captive animals in an effort to help fight heart disease in apes, three of which have been trained to present their chests to a scanner to upload the data (image above). This research will hopefully lead to updated recommendations on exercise and diet for captive animals.

Source:
Chicago Tribune

Comments

  1. #1 jane
    May 17, 2012

    Okay, I am an animal lover – enough of one in fact that I do not think our nearest relatives should be kept in zoos – but this is a bit over the top. What does this woman think aging or downright elderly chimps in zoos, who don’t die young from parasitic diseases or warfare, ought to die of? Cancer? Kidney failure? Dementia? They’re not immortal, so they’ve got to die of something! It reminds me of the doctors who cram pacemakers into nursing home residents.

  2. #2 NJ
    May 17, 2012

    jane @ 1:

    this is a bit over the top

    In what way, for crying out loud? Studying disease X in elderly examples of species Z is a way to help all members of of the same and similar species.

    What does this woman think aging or downright elderly chimps in zoos, who don’t die young from parasitic diseases or warfare, ought to die of?

    Ah…..you are committing an is/ought fallacy. There is no mention of what these chimps ‘ought’ to die of, just of what ‘is’ killing them. Suggest you do some remedial work on logical fallacies.

  3. #3 Calli Arcale
    May 18, 2012

    jane, I don’t think anybody thinks that chimpanzees ought to die of anything in particular. But when one takes an animal into captivity, or raises an animal born in captivity, one accepts certain responsibilities, and the biggest of those is to care for the animal’s welfare. If vets can improve their quality of life by preventing heart disease, that’s a good thing, but it means first understanding how the heart disease progresses in them.

    BTW, my grandmother, who passed away last Monday, had a pacemaker. She wasn’t in a nursing home when it was implanted, but she was quite advanced in age. She wasn’t ready to die at that point, though, and using a pacemaker to prevent additional heart damage made excellent sense. Even if it doesn’t prevent the patient’s eventual death, it improves quality of life tremendously; they have more energy, and they don’t suffer pain as more of their heart is injured by a bad rhythm. There’s a lot more to medicine at the end of life than just “can it keep the patient alive”. Consider this: my husband’s grandmother who died in 2007 had reached a terminal stage. They nevertheless gave her antibiotics for her pneumonia. Why? Because she was in a lot of pain, and although killing the bugs wouldn’t save her life, it made her eventual passing a lot less painful. Some people call pneumonia the final gift, because it ends the suffering; she was on a ventilator, and did not need the pain of pneumonia when she wished to let go; she just had to order the machine disconnected.

  4. #4 jane
    May 18, 2012

    NJ, your message doesn’t represent your beliefs very well. Let me try to explain mine better. Assuming that you, personally, don’t die prematurely of some accident or genetic defect, you WILL die by a certain age of something else – probably heart disease, cancer, or dementia. If you could take a magic pill that reduced your risk of heart disease to zero, that would automatically increase your risk of dying of cancer or dementia. Getting upset because a third of zoo chimps die of heart disease makes no more sense, absent age data, than saying the same about humans. The relevant question is, what percentage die prematurely of heart disease? If animals are being provided with a sufficiently healthful environment that they live to old age, they, like us, will inevitably suffer the diseases of old age.

    Calli – My condolences on your loss, and I’m glad that it worked out well for your grandmother. Pacemakers also have great potential to cause cardiac damage, especially through ventricular pacing and through tricuspid regurgitation, so the decision to get one usually should involve second if not third opinions. Putting pacemakers or ICDs in nursing home patients – which is done – was a random example, but in general, I do not believe we have a moral duty to provide similarly aggressive care to elderly animals in our custody. For one thing, animals might well prefer peaceful death in early old age to a few more years of constant pills and procedures (as, indeed, would I). They are not known to suffer our obsessive fear of mortality, so it makes little sense for us to suffer it on their behalf. I would lay down my life for my cat, but I would not put her, in old age, through chemo or a transplant.

    That’s not because I couldn’t pay for it, but because I don’t want her to suffer. But the resource-intensive nature of prophylactic medicine is a fair consideration. Americans are just starting to recognize the fact of resource limitations. The medical industry is breaking our budgets; we can’t even afford to provide constant hi-tech medical care to our entire human population. We can’t possibly afford to provide it to hundreds of millions of animals as well. I don’t believe that one can have a moral duty to do something that one is physically incapable of doing. I’ve worked with people in less-developed countries who can’t obtain basic vet care for their cats and dogs, and have never heard of “pet food”; I can’t imagine trying to explain to them that they should get their dog a pacemaker.

  5. #5 Calli Arcale
    May 18, 2012

    I think you’re taking this a bit far, jane; studying heart disease in chimpanzees is for *basic care*. They want to know if captive life is shortening their lives by putting them at risk for heart disease. That’s a reasonable question. If it is, they have a *duty* to mitigate that risk. Additionally, captive chimpanzees are available for basic biological research, and it’s reasonable to conduct it so our zoos aren’t making decisions blindly.

    Honestly, I think it’s fairly silly to compare zoo care with the heroic measures some families insist be taken for their loved ones who no longer have the capability to make decisions on their own. Zoos have, and often exercise, an option not available and generally fiercely opposed in human care: euthanasia. That’s what becomes of an animal that ill or infirm. If you compare it to nursing home care, I’m not sure which side you’ll offend more because of that.

  6. #6 jane
    May 19, 2012

    Yes, and I certainly intend to select euthanasia for myself if and when I become intractably ill. You give the appearance of believing that I have an exaggerated impression of how much medicalization of zoo animals this is meant to lead to, which is possible. Perhaps they only want to identify lifestyle changes that may reduce premature CV death in captive animals, in which case they are not, as you might say, silly. The blog entry does not make this clear; for one thing, it does not discuss the age at which the animals are dying. If they are dying prematurely, there’s a problem that should be solved. But many captive chimps are reported to live to ripe old ages. If they’re getting heart disease in what is for them old age, saying we have a “duty” to do something about it looks like an attempt to extend the values, if not the technologies, of American-style cardiology to other species.

    However, the chimps currently at issue, who have had monitors surgically implanted in them, are certainly getting a lot of tech from which they are not likely to derive a net benefit. Is that ethical if the only goal is to learn about the natural process of cardiovascular disease in apes, since we already have a large population of sedentary apes (i.e., Americans) from which we have learned far more than we can from these few apes? If they could have been asked, would they have consented to such surgery?

  7. #7 NJ
    May 19, 2012

    jane@4:

    your message doesn’t represent your beliefs very well

    Well, how kind of you to understand my beliefs for me! How would I ever have followed them without you to explain them to me?

    (Meta note: Would this be an example of femsplaining?)

    Assuming that you, personally, don’t die prematurely of some accident or genetic defect, you WILL die by a certain age of something else

    True. And the first rule of tautology club is…the first rule of tautology club. You aren’t really helping your case here.

    Getting upset because a third of zoo chimps die of heart disease makes no more sense, absent age data, than saying the same about humans.

    So, (reductio ad absurdum) since everyone will die of something, there is little to no point in trying to understand the mechanisms of any disease. Good! I hate wasting all that money on the NIH…

    they, like us, will inevitably suffer the diseases of old age.

    …which is a reason not to study such diseases why? Obviously some will suffer those diseases prematurely, so such research can be of objective help.

    jane@6:

    the chimps currently at issue, who have had monitors surgically implanted in them, are certainly getting a lot of tech from which they are not likely to derive a net benefit.

    And since those specific chimps are not likely to derive a benefit, no other chimps nor any other species will derive any benefit.

    Expanding on the point I made earlier, a careful study of

    May 21, 2012

    jane, evidentally I misunderstood you; I thought when you compared this to putting pacemakers into nursing home residents and expressed outrage at the study that you meant it was a bad thing. When you replied and discussed how it isn’t appropriate to provide aggressive care to animals, I thought you were suggesting that was what was being done in this case.

    Fact is, we do not know what the average life expectancy of a chimpanzee ought to be. It is often said that they live to ripe old ages in zoos — but how do we know this? We know how long they *do* survive in captivity, and we have some data of mixed quality on how long they survive in the wild. But in ideal circumstances, what is the life expectancy of a chimp? We don’t really know. If they die of a heart attack at 45, is that premature or not? We don’t know, and we can only know by studying them.

    Is that ethical if the only goal is to learn about the natural process of cardiovascular disease in apes, since we already have a large population of sedentary apes (i.e., Americans) from which we have learned far more than we can from these few apes?

    Yes, it’s ethical. Can we learn more from humans than we can from captive apes? Yes and no. Heart disease in great apes is clearly very similar to heart disease in humans. But even among humans it is variable, and we don’t know enough to say that humans are an adequate proxy species for chimpanzees in medical research. We’re close, definitely. But we need more details to understand the normal rate of decline among apes and how heart disease progresses in them. Implantable devices have the advantage of monitoring the animals in more normal behavioral settings, even animals who might not tolerate wearing a portable EKG for a few days (as a human study subject probably would). Training them to submit to ultrasounds is another hugely valuable tool in better understanding the disease in these animals, and I hope they also move to training them to perform tests so they can develop standardized stress tests for great apes, since human stress tests depend on endurance running. That’s a unique trait among primates; chimps can’t do it.

  8. #9 Benjamin Urrutia
    Chicago, Illinois
    May 30, 2012

    Do Chimpanzees get Congestive Heart Failure? I have that disease, so I have a personal interest!