The research was performed by a group of scientists from Rice University in Houston, Texas, on a group of 159 people of both sexes, aged 18 to 55. The participants, who volunteered for the experiment, were preliminarily examined for psychological and physical health, and then subsequently given cold-inducing nasal drops. After being infected, they were quarantined for five days in hotel rooms.
The scientists monitored the participants over the course of their quarantine. The observation results were adjusted to take various factors, such as age and gender, into account. What the scientists discovered was that people who felt lonely tended to report more severe symptoms of their illness than those who didn't.
"Loneliness puts people at risk for premature mortality and all kinds of other physical illnesses," graduate student Angie LeRoy, co-author of the study, said in a Rice University press release. "But nothing had been done to look at an acute but temporary illness that we're all vulnerable to, like the common cold."
According to the scientists' team, similar research has found that a host of stressful conditions can make people feel worse physically. The current research focuses specifically on common colds and loneliness.
"Previous research has shown that different psycho-social factors like feeling rejected or feeling left out or not having strong social bonds with other people do make people feel worse physically, mentally and emotionally," LeRoy said. "So we had that general framework to work with."
"What makes this study so novel is the tight experimental design. It's all about a particular predisposition (loneliness) interacting with a particular stressor," said Rice psychologist Chris Fagundes.
The research team insists doctors should take psychological factors into account on a regular basis.
"It would definitely help them understand the phenomenon when the person comes in sick," Fagundes says.
But there is also a more mundane aspect to the problem.
"We think this is important, particularly because of the economic burden associated with the common cold," says LeRoy. "Millions of people miss work each year because of it. And that has to do with how they feel, not necessarily with how much they're blowing their noses."
