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DURHAM, N.C. - It has been known for some time that social
isolation increases the risks of heart patients suffering
further from their disease or even dying, but until now
researchers didn't have a clear idea of which particular
patient characteristics are responsible for these increased
risks.

A new study by researchers at Duke University Medical Center
has ruled out certain psychosocial and environmental factors
thought to be behind the increased risk, and uncovered
potential difficulties in finding ways of helping this group of
patients.

"For heart patients with small social networks, we found
that the increased risks were not attributable to severity of
their disease, social status, or whether or not a patient was
distressed," said lead researcher Beverly Brummett, who
published the results of the Duke team's study today (March 23)
in the journal Psychosomatic Medicine.

The research was supported by grants from the National
Heart, Lung, and Blood Institute and the National Institute on
Aging, both parts of the National Institutes of Health
(NIH).

"We expected that these isolated patients would have higher
levels of distress -- depression or stress -- but we were
surprised to find that this wasn't the case," Brummett
continued. "These data suggest that it could be hard for us to
get in there and intervene -- the patients appear to be
isolated and want to stay that way. They may be resistant if we
try to intervene."

The researchers did find that people with a support network
of fewer than three were more than twice as likely as patients
with larger networks to die from their heart disease during the
study's follow-up period, which averaged four years.

The concept of social network is very open-ended. It does
not necessarily mean the patients have regular contact with
close friends or family members, but any person with whom the
patient would have regular contact during the day qualifies as
being a part of a social network.

"We asked these patients many different questions in many
ways, and still the most isolated people could only come up
with two or three people with whom they have interactions,"
Brummett said. "We're not talking necessarily about confidants
or close friends, but just normal human contact, like one would
have in the work or social environment."

While many studies have looked at the effects of social
isolation on health, the group of patients that Brummett's
group analyzed is one of the most well-characterized -- the 430
patients took an exhaustive battery of psychological and
psychosocial tests. This allowed researchers to control for a
wide variety of environmental, medical and psychological
factors.

The researchers described that following characteristics of
the isolated patients:

-- They reported fewer than half the number of visits
reported by non-isolated patients.

-- More than one-third of the isolated patients averaged
less than one network contact every three days.

-- One-fifth of the isolated patients failed to name one
person who provides emotional support during everyday life or
during a crisis.

-- More than one-third reported no one with whom they could
discuss important decisions during a time of crisis.

-- Isolated patients were less likely to be married.

-- Though isolated patients did not differ from non-isolated
patients in attending religious services, they did report less
participation in other, more social religious activities.

Also, according to Brummett, the isolated patients tended to
have lower incomes and tended to smoke more, but after
statistical analysis, these environmental factors could not
explain the increased risk. Psychologically, the isolated
patients tended to be more hostile, but once again this factor
did not contribute to the increased risk, she said.

"What we also found so intriguing was that from their own
perspectives, most of these isolated patients did not perceive
themselves to be socially isolated," Brummett continued. "They
seemed content with their level of support. This presents a
real challenge for those attempting to develop new approaches
to help these patients."

While the current study does not conclusively explain why
the most isolated heart patients are at such a high risk of
dying from their disease, it does call into question some
prevailing views on the role of isolation and mortality,
Brummett said. Her analysis demonstrates that the increase in
risk is not due to disease severity, socioeconomic status,
depression or hostility.

"Further prospective studies are needed to fully understand
the interplay of the factors in this phenomenon," Brummett
added.

One such study is under way. Duke is in the final year of an
NIH-supported, multi-center clinical trial to measure the
effects of psychological counseling and group therapy in
protecting heart patients from future heart attacks. The trial,
known as ENRICHD (Enhancing Recovery in Coronary Heart Disease
Patients), enrolled more than 3,000 patients and is the first
such trial to investigate the promise of such
interventions.

Joining Brummett in her study were Duke colleagues John
Barefoot, Ilene Siegler, Nancy Clapp-Channing, Barbara Lytle,
Hayden Bosworth, Dr. Redford Williams and Dr. Daniel Mark.