Study links IQ and affluence level to longevity

September 24, 2003

By following nearly 1,000 subjects during a 70-year span, Scottish researchers have found that people with high IQs who reside in poor neighborhoods lived longer than people in similar areas with low IQs, while the intelligence score was not important for longevity for people living in wealthy neighborhoods.

"The significant interaction found between IQ and deprivation suggests that IQ in childhood is less important in terms of mortality for people who live in more affluent areas in adulthood than for people who live in deprived areas," says Carole L. Hart, Ph.D., of the University of Glasgow and colleagues from other universities in Scotland.

Their findings are published in the September issue of Psychosomatic Medicine.

The high-IQ individuals may have lived long lives because they learned better health behaviors early in life or because higher mental ability allowed them to better cope with adverse situations over the years, the researchers suggest.

The study examined results of the Scottish Mental Survey, an intelligence test held June 1, 1932, for 87,498 Scottish schoolchildren born in 1921.

The researchers then compared this data to records from a group of medical studies of adults in Scotland carried out in the 1960s and 1970s. These "Midspan" studies collected data about the subjects' home address, age and occupation, along with information about their cardiovascular and respiratory health.

Two of the Midspan studies enrolled more than 24,000 working-age participants -- including some born in 1921. Hart's team was able to match 938 of these subjects to their mental ability scores on the 1932 test. Based on home neighborhood and occupation, they then categorized the subjects according to deprivation and social class. Finally, they used health and hospital records to determine the causes and dates of death of this group over the next quarter-century.

Over those 25 years, 51 percent of the men and 38 percent of the women in the study died. In simple terms, there was a 17 percent greater chance of death for every 15 points of lower childhood IQ. After adjusting for deprivation and social class, this difference was reduced to 12 percent. These adjustments separated socioeconomic effects from IQ and explained some, but not all, of the differences associated with lower IQ.

"The analysis by IQ, divided into four groups, showed that it was the lowest group that had an increased relative rate of all-cause mortality," Hart says.

She adds that there is still much work to be done to explain the mechanisms by which childhood IQ is reflected in death rates decades later.

"It is possible that low childhood IQ leads to adult deprivation, which in turn leads to earlier death," she says. But it is also true that low birth weight or adverse circumstances in childhood lead to lower IQ at age 11 and also to poorer health outcomes. Hart's team will keep studying the combinations of data provided by others starting 70 years ago and continuing to the present.
-end-
Funding for the study was provided by the Chief Scientist's Office of the Scottish Executive.

FOR MORE INFORMATION
Health Behavior News Service: (202) 387-2829 or www.hbns.org.
Interviews: Contact Judith Hodgson at j.hodgson@admin.gla.ac.uk or +(44) (141) 330-3535.
Psychosomatic Medicine: Contact Victoria White at (352) 376-1611, ext. 5300, or psychosomatic@medicine.ufl.edu. Online, visit www.psychosomaticmedicine.org.

Center for Advancing Health

Related Longevity Articles from Brightsurf:

Women's expected longevity linked to age at birth of last child
CLEVELAND, Ohio --No one knows for sure how long they will live.

Buckwheat enhances the production of a protein that supports the longevity
A healthy low-calorie diet that contains plant products can help us improve the level of sirtuin 1 (SIRT1) protein production that is known to increase life expectancy.

A balancing act between immunity and longevity
Changes in the immune system can promote healthy ageing

Strenuous daily exercise may shorten, not prolong, longevity
By analyzing longevity data for professional Japanese traditional artists, researchers at Tokyo Institute of Technology have found that Kabuki actors, known for their vigorous movements, surprisingly had shorter lifespans compared with other traditional arts performers who lead mostly sedentary lifestyles.

Not smoking and being socially active keys to longevity
University of Otago researchers have discovered some of the secrets to longevity with new research revealing not smoking and being social engaged throughout older age are common traits of New Zealand centenarians.

Nutraceuticals for promoting longevity
The review, published in Current Nutraceuticals, offers a special focus on the nutraceuticals that impact insulin-like growth factor 1 receptor signaling and sirtuin activity in mediating longevity and healthspan.

Subcellular chatter regulates longevity
As people get older, they often feel less energetic, mobile or active.

Characterizing two sisters, examples of exceptional longevity
A new study provides a detailed characterization of two sisters -- one a supercentenarian and one a semi-supercentenarian -- aimed at providing new insights into what allowed them to live such long lives.

Women, exercise and longevity
Women who can exercise vigorously are at significantly lower risk of dying from heart disease, cancer and other causes.

Deep biomarkers of aging and longevity: From research to applications
The deep age predictors can help advance aging research by establishing causal relationships in nonlinear systems.

Read More: Longevity News and Longevity Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.