Longevity Data from the Lifetime Cardiac Study
06/01/2016

(note: please see the PDF version of this article in Focus for relevant graphs)

Alex Comfort utilized meticulous records for 189 hounds from a kennel in Ireland to report a life span of 5.8 years. These hounds died between 1927-1945. Mortality was very high for young males. But males living longer than 10 years (4 of the 75 who survived past 3 years) died of heart disease with no cancer reported. Specifically there was no reported osteosarcoma in either dogs or bitches in this kennel.

In 1974 Darling also reported a life span of 5.8 years- not much progress. Gretchen Bernardi reported lifespan of 6.47 years in hounds dying 1966-1986. The main cause of death was cancer with 21% of all hounds dying from osteosarcoma.

Data from the LCS showed life span of 7.45 years in hounds dying 2000-2015 main cause of death was cancer with 20% of all hounds dying from osteosarcoma.

There are also many reports of longevity available from European populations of hounds.

Major Killers Over the Years

Overall changes in the 20 year interval include a marked decrease in death from bloat. This does not document a lower incidence of bloat, just lower incidence of death from bloat and may reflect, earlier diagnosis and better surgical techniques and anesthesia.

The percentage of hounds dying from osteosarcoma and cardiac disease is stubbornly similar but there has been a small increase in life span for hounds with these major killers.

Rear weakness has become the third leading cause of death. Heavier hounds? Less exercise and fitness? Just a larger population of older hounds? The age at death for euthanasia for rear weakness or “hound could not get up” is 9.3 years.

It is proclaimed common knowledge that bitches live longer than dogs. Yet Bernardi found it was only .5 years with bitches dying 6.55 years and dogs 6.0 years. This study had a nearly even population gender split with 291 males and 274 bitches.

Twenty years later the LCS data showed bitches still lived only .55 years longer than dogs. This data had more bitches in the population (452 bitches and 367 males).

Changes During LCS

Data was also examined from 2000-2006 and compared to 2006-2015. There was a decrease in deaths from cardiac disease but no decrease in deaths from osteosarcoma.

In the later half of the study death from rear weakness surpassed death from cardiomyopathy.

Cancer is the major killer of our hounds with no decrease in incidence in the last 20 years (36.6%).

Osteosarcoma is BY FAR the most common cancer in IWs and kills 20% of ALL our hounds. This incidence has not decreased although the average age at death is slightly improved 6.6-7.0 years.

The next two most common cancers are lymphoma which killed 4.7% of all hounds and at a younger age (average age at death was 6 years) and hemangiosarcoma which was diagnosed in 2.3% and killed older hounds (8.5 years). These are followed by many other cancers including breast, stomach, prostate, lung.

The next leading cause of death overall is cardiac. In the LCS study documentation of cardiac disease was required and sudden death was excluded thus incidence may have looked lower than in other reported studies.

The third leading cause of death is rear weakness.

The 4th leading cause of death is other. This was a large number of 1 or less % with “incompetent vet” leading the way followed by post op complications, poison, volvulus, other GI problems etc etc.

Pneumonia continues to be a significantly killer of IWs at 4.49% of deaths.

Overall sudden death was reported in 3.58% of hounds. These were dogs found dead unexpectedly without a known diagnosis of heart disease.

The difficulties in determining accurate cause of death have been previously described by Bernardi and have not improved in the last 20 years. Some diagnoses are clear such as osteosarcoma or mammary cancer or lymphoma while the diagnosis of hemangiosarcoma can be elusive so the reported incidence is probably low.

Despite all the difficulty with diagnosis and the passage of 20 years the killers of our hounds remain remarkably unchanged.

Other notes on Cause of Death

It has also been reported that males have a higher incidence of osteosarcoma than females. However neither Bernardi nor the LCS data verified this. In the overall osteosarcoma populations there were actually more affected bitches. However, when the data was broken down for age groups there is a marked preponderance of males in young hounds (under 5) which is lost as hounds age. The same holds true for cardiac death with a marked preponderance of males in the 5 and under population. This gender difference is not as dominant in the older hounds.

Over the past 20 years there has been an increase in the lifespan of the LCS reported population of North American IWs.

The major killer of IWs is cancer at 36.6% (no decrease in the past 20 years).

Osteocarcoma, responsible for 20% of all deaths, continues to be the number one killer of IWs. Osteosarcoma also shows a marked male preponderance in young dogs (under 5) but overall incidence even dogs/ bitches.

Lymphoma and hemangiosarcoma are the second and third causes of cancer death.

In the LCS data heart disease was overall the number 2 killer of hounds but the incidence has decreased in the last 10 years.

The number of deaths from bloat has markedly decreased in the last 20 years.

Euthanasia for rear weakness or “hound could not get up “is now the 3rd leading cause of death.