Let Your Dog Keep IT's Ovaries and You SHould Keep Yours Too!
Ami Moore
www.dogdoright.com
www.chicagodogcoach.com
Dr. Waters' ideas aren't anything all that new when it comes to women's health, longevity, and ovary conservation. But he's correct that we need to learn the underlying mechanisms at work, and how they differ for each individual, whether human female or canine female.
There have been a number of good studies with women that show that bilateral oophorectomy decreases lifespan. Although mortality after bilateral oophorectomy for breast cancer and ovarian cancer decrease, overall mortality increases. Here's just one of the more recent studies:
"Women who had undergone bilateral oophorectomy had an increased risk of CHD and all-cause mortality (TABLE). The authors estimated that with a postsurgical life span of approximately 35 years, every 9 oophorectomies would result in 1 additional death. The authors also pointed out there were no age exceptions: Ovarian-sparing surgery was linked to improved survival in every age group.
Oophorectomy did have a protective effect against breast cancer, ovarian cancer (number needed to treat=220), and total cancer incidence, but it was associated with an increased incidence of lung cancer (number needed to harm=190) and total cancer mortality. There was no significant difference in rates of stroke, pulmonary embolus, colorectal cancer, or hip fracture."
From:
http://ping.fm/pgjmU
Ovary-sparing hysterectomy: Is it right for your patient?
Umang Sharma, MDSarah-Anne Schumann, MD
Department of Family Medicine, The University of Chicago
PURLs EDITOR — John Hickner, MD, MSc
Department of Family Medicine, Cleveland Clinic
The Journal of Family Practice - September 2009 (Vol. 58, No. 9)
you can find the actual study cited at this link:
http://ping.fm/QhsJW
http://tinyurl.com/dxwg9l
Ovarian Conservation at the Time of Hysterectomy and Long-Term Health Outcomes in the Nurses' Health Study
Obstetrics & Gynecology:
May 2009 - Volume 113 - Issue 5 - pp 1027-1037
Parker, William H. MD et al
There are a number of previous studies that have been done that have come to the same conclusion (lower mortality rates in women who have kept their ovaries compared with those who haven't) - just search in PubMed and you'll find them.
One interesting conclusion in the above human study is (quoting from above): "The authors also pointed out there were no age exceptions: Ovarian-sparing surgery was linked to improved survival in every age group." Dr Waters found similarly, saying the following in the article that he co-authored: "...dogs with the longest ovary exposure (6.1 - 8.0 years) were 3.2 times more likely to reach exceptional longevity than dogs with shorter exposures (P = 0.0002.)"
So, while might be way too premature to say with certainty, it's possible that -barring of course serious illness, such as ovarian cancer in a woman - there is no "safe age" at which ovaries can be removed, in either dog or human without running an increased risk of adverse sequelae down the road.
Quite frankly, for both dogs, and humans, I simply can't understand why this information isn't made more widely available.
Very coincidently, I'm currently enrolled in a graduate level biology course entitled The Biology of Aging, at Northeastern Illinois University in Chicago, which is taught by a professor who has done considerable original research in this field (although his organism of choice in research is the Paramecium). A portion of this week's lecture was the role of free radicals in the aging process, and we learned how estradiol (one of the estrogens) acts as a highly effective free radical scavenger, alternating with estrone (another of the estrogens), and slowing down the overall aging process in various lab animals models in which this process has been studied.
My own guess is that this might be one of the plausible reasons supporting the apparent direct relationship between "years of ovarian exposure" and longevity in both dog and human, especially since - as both Dr Waters et al in the Rottie study, and Dr Parker et al in the human study (above) have found - a number of varied diseases are responsible for the increased mortality rates in both humans and dogs following bilateral oophorectomy.
