New research reveals how loneliness can undermine health

Although doctors have been aware that lonely people have more medical problems and do not live as long as people who are not lonely, physicians have been unsure of the reasons for this connection. Recent research at the University is now providing some answers.

New research at the University demonstrates that loneliness undermines health by altering people’s cardiac function and disrupting their sleep. The new findings also show that lonely people may have more health problems because they perceive the world to be threatening and their orientation to others reduces positive feedback and emotional support.

These perceptions can ultimately lead to higher blood pressure and sleep disruptions, and these factors, in turn, have been shown to have an impact on the body’s resilience in dealing with disease.

“The strength of social isolation as a risk factor is comparable to obesity, sedentary lifestyles and possibly even smoking,” said John Cacioppo, the Tiffany and Margaret Blake Distinguished Service Professor in Psychology and director of an interdisciplinary team of investigators studying loneliness as part of the Mind-Body Network of the John D. and Catherine T. MacArthur Foundation.

Cacioppo reported his findings in a paper titled “Biological Costs of Social Stress in the Elderly” at the Aug. 6 meeting of the American Psychological Association in Washington, D.C.

The findings about loneliness are significant because lifestyle changes have altered the structure of the family, the traditional source of emotional support. U.S. Census Bureau projections show that by 2010, 31 million Americans will be living alone, a 40 percent increase from 1980.

Being alone is not the only cause of loneliness, however.Cacioppo explains that loneliness is characterized by three conditions: isolation (such as absence or distance from a romantic partner), feelings of being disconnected (not having close friends) and feelings of not belonging (not identifying with or not being accepted by valued social groups).

For the study, Cacioppo and his colleagues tested 89 students (45 men and 44 women) aged 18 through 24 at Ohio State University and 25 older people in Chicago, a group in a pilot study that provided evidence for the long-term impact of loneliness.

The students at Ohio State were selected because they scored in the upper and lower quintile of a standard loneliness test. “We found that there was no difference among the students in characteristics normally associated with loneliness. The students had friends and were involved in activities,” Cacioppo said.

The students, who were asked to solve mathematics problems and give short speeches, were tested for cardiac function. They also were given psychological tests to determine their responses to typical and difficult situations.

The study found no differences in the health habits of the students or in their cortisol levels, which are measures of immune response.

During the evening, they were attached to an electronic monitor to record their sleep patterns.

Researchers found that in response to the stressors, the lonely students, who felt threatened, showed increases in blood pressure fueled by increases in the resistance to blood flow through the body. While the blood pressure of the nonlonely students also increased, that change was due to more blood being pumped through their bodies in response to feeling challenged by the stressors.

They also found that lonely and nonlonely students spent approximately equal amounts of time in bed, but lonely individuals slept 5.8 hours on average while nonlonely students slept 6.4 hours. The lonely students also had a more restless sleep, awakening, for instance, more often during the night.

Researchers next tested a group of 19 women and six men in Chicago aged 53 through 78 to determine the long-term impact of loneliness. The older participants completed tests to determine their degree of loneliness and other tests similar to the ones given to the university students.

As with the young participants, the team found no differences in health habits or cortisol levels among the lonely and nonlonely older people.

The differences among older people in sleep patterns and cardiac responses were similar to the differences between lonely and nonlonely students. The blood pressure of lonely participants in the 65- to 78-year range was 16 points higher than that of the nonlonely participants. Cacioppo said that among older people, a lifetime of loneliness leads to diminished health, as they experience continued high blood pressure and chronic sleep deprivation.

People can improve their health by learning to overcome loneliness, Cacioppo said. For example, people can become contributing members to school, neighborhood, church or community groups.

“A good time to start, which people often overlook, is when a person is in a new social situation, such as when they’ve moved to a new community. Our research shows that people aren’t lonely simply because of a personality trait, such as being shy. By reaching out to make friends and helping others, people can increase their connections with others.”