Falling Heart Disease Rates Could Be A Thing Of The Past

Featured Article
Main Category: Heart Disease
Article Date: 12 Feb 2008 - 0:00 PDT

email to a friend   printer friendly   view / write opinions   rate article

The falling rates of heart disease enjoyed by the US population since the 1960s may be a thing of the past, and may even be on the rise again, according to data from autopsies.

This is the finding of a study by researchers in the US and Canada that is published in the 11th February issue of the Archives of Internal Medicine.

The researchers, Dr Cynthia Leibson, and colleagues from the Mayo Clinic, Rochester, Minnesota, and the University of British Columbia, Vancouver, Canada, wrote that over the last 100 years or so the "rate of death due to heart disease in the United States rose until the mid 1960s when it began a steady decline".

This long steady period of decline appears to have been accompanied by falls in incidence and rates of death of coronary artery disease, they wrote, which is the most common type of heart disease, which occurs when the vessels supplying blood to the heart get blocked.

Studying autopsy data is a highly reliable way of finding out what people die from. But you have to have a high rate of autopsies in a population, and within that, it has to be a representative cross section, to be reasonably accurate about the causes of death in the population as a whole.

Across the US as a whole, the national autopsy rate has never been high, and if anything it is going down. In 2003, only 8.3 per cent of deaths in the US as a whole were investigated by autopsy. However, there is one part of the US, Olmsted County, Minnesota, where this is not the case. Here, they have a high autopsy rate across all age groups, and especially for non-elderly people who died of unnatural causes such as accidents, homicides or suicides.

So Leibson and colleagues looked at death certificates and pathology reports to work out trends in coronary artery disease among non-elderly residents of Olmsted County who died of unnatural causes.

Their results showed that:

• 3,237 Olmsted County residents aged 16 to 64 died between 1981 and 2004.


• 515 of those deaths were from unnatural causes, and nearly all (96 per cent) were autopsied.


• They were able to give 82 per cent (425) of the 515 deaths grades depending on the amount of blockage that the autopsies found in the arteries. Grade 0 meant no blockages were found, and grade 5 meant 100 per cent blockage was found.


• 8.2 per cent of the 425 non-elderly people who died from unnatural causes between 1981 and 2004 had high grade disease (grade 3 or higher in the left main artery, or grade 4 or higher in any other single artery), and 83 per cent had any disease.


• After adjusting for age and gender, the results showed a decline over the whole period for high grade disease, any disease and the average grade of disease.


• But, as the authors wrote, "declines in the grade of coronary disease ended after 1995 and possibly reversed after 2000."

The researchers concluded that: "Our finding that temporal declines in the grade of coronary artery disease at autopsy have ended, together with suggestive evidence that declines have recently reversed, provides some of the first data to support increasing concerns that declines in heart disease mortality may not continue."

Speculating on the reasons for this reverse in the decline, they cautiously pointed to the rise in obesity and diabetes by mentioning:

"The extent to which recent trends are attributable to the epidemics of obesity and diabetes mellitus awaits further investigation."

In an accompanying editorial, Drs Jay Olshansky and Victoria Persky of the University of Illinois at Chicago, wrote that given the growing body of evidence on the rising rates of childhood obesity, this study:

"Underscores the importance of focusing prevention efforts on lifestyle factors among younger generations, including continued efforts to decrease smoking and encouraging healthy diets and moderate physical activity, before clinical symptoms of coronary artery disease have an opportunity to be expressed."

Although this study is limited to a small sector of the American population, its findings should nevertheless ring alarm bells with public health officials who should "begin monitoring younger cohorts for early signs of coronary artery disease with much greater vigilance," they added.

"Recent Trends in the Prevalence of Coronary Disease: A Population-Based Autopsy Study of Nonnatural Deaths."
Peter N. Nemetz; Veronique L. Roger; Jeanine E. Ransom; Kent R. Bailey; William D. Edwards; Cynthia L. Leibson.
Arch Intern Med. 2008;168(3):264-270.
Vol. 168 No. 3, February 11, 2008.

Click here for Abstract.

Sources: journal abstract, JAMA press release.

Written by: Catharine Paddock, PhD
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today