Sometimes, life kicks you when you're down.
According to new research, that crummy, achy, sneezy feeling you get when you have a cold is worse if you are also feeling lonely.
In the study, published Thursday in the American Psychological Assn.'s journal Health Psychology, the authors report that lonelier people complained of 38.5% more severe symptoms than those who were less lonely.
Previous research has shown that loneliness is associated with negative health outcomes in chronic diseases such as cancer and heart disease, but nobody had looked at whether it also played a role in the outcomes of more common illnesses like the cold — until now.
"We wanted to see there would be a similar effect with an everyday illness that we all experience," said Angie Le Roy, a graduate student at the University of Houston who led the work.
To find out, Le Roy and her colleagues recruited 213 individuals who agreed to be infected with rhinovirus 39 — a common cold virus. (Yes, they were paid. Participants received $1,060 for completing the study).
These two may sound similar, but they are not the same. Le Roy explained that feeling lonely does not necessarily mean one has a small social network.
"You can be surrounded by lots of people and still feel lonely," she said.
Next, the researchers used nasal drops to give participants the cold. Those who were infected (160 out of the original 213) were quarantined in individual hotel rooms for five days. During this time they received three meals per day in their room and had only minimal contact with other volunteers and the people running the study. They also recorded their cold symptoms each day.
When the authors crunched the data, they found that while lonelier people reported worse cold symptoms, the size of the participants' social network had no effect on their experience of the cold. This held true even when they controlled for other factors such as how depressed a person was, or the season that they contracted the cold.
To test if lonely people actually had worse colds than less lonely people, one of Le Roy's collaborators had the unpleasant task of gathering all the dirty tissues used over the course of the experiment and weighing them to see how much mucus each participant produced.
The authors report that there was the same amount of mucus in the tissues of lonely people and less lonely people, suggesting that loneliness is not associated with an objective common cold indicator of mucus production.
"The perception of how they felt was the effect we found," Le Roy said.
But keep in mind, it's the perception of "not feeling well" and not necessarily how objectively sick we are that keeps us home from work or school when we have a cold or other illness. And that has serious economic effects. The authors cite a 2002 study that found that the economic cost of productivity that can be blamed on the common cold is close to $25 billion.
The current study does not address why lonely people might feel sicker when they have a cold. I wondered if it might be that lonely people don't have anyone to bring them chicken soup, make them tea or just generally take care of them when they are feeling sick, but everyone who participated in the study was essentially in isolation for the five days that they had the cold so that doesn't explain the findings.
Le Roy said she and her team can't answer that question yet, although they'd like to someday. In the meantime, she said the study has implications especially for the medical community.
"I'm hoping that research findings like this one will make doctors want to expand their intake assessment histories to include psychological well-being and relationships," she said. "It's not a traditional way of looking at medicine, but it provides insights into more holistic and comprehensive care."
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