WASHINGTON - Whether your parents or grandparents are home alone or living in a retirement community, they may feel left out and isolated, and it could affect how long they live and how much help they need later in life.
The University of California, San Francisco followed 1,604 people over 60 and found more than 43 percent of them feel chronically lonely.
During a six-year follow-up period, the study's researchers found more than half of the people studied had difficulty with basic housekeeping and personal tasks.
Additionally, the lonely individuals had a 45 percent higher risk of an early death.
Most of the lonely people - 62.5 percent - were married or living with others, according to The New York Times.
Dr. Carla M. Perissinotto, who led the study, says you can't tell who may be feeling lonely, adding that the health effects of loneliness can't be ignored.
Other studies connect chronic loneliness with high blood pressure, coronary heart disease, depression and dementia.
The research comes as America grays and divorces. Roughly one-third of Americans between 45 to 63 are single.
It's estimated that 20 percent of the population and 40 percent of people over 65 are chronically lonely.
Dr. Louise C. Hawkley, a psychologist at the University of Chicago, tells the Times how people think about others contributes to the problem. She says lonely people look for signs of rejection. As a result, they come off as aloof or critical.
"Then, people become more careful around you, so a self-fulfilling prophecy or a loneliness loop develops," Hawkley tells The New York Times.
Key to healthy aging, health professionals say, is for older individuals to continue to build new friendships as they age, especially after retirement.
Perissinotto says the quality of relationships matters. While her study didn't look at why the individuals felt lonely, she says the next step of research needs to delve into whether loneliness is biological and whether lonely people are "simply not caring for themselves."
WTOP's Jeanne Meserve contributed to this report. Follow WTOP on Twitter.
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