Lonely hearts call in sick more

The immune systems of chronically lonely people overexpress pro-inflammatory genes, while underexpressing anti-inflammatory genes, according to researchers from the University of California, Los Angeles.

The findings provide a link to why lonely people have an increased risk of heart disease, viral infections, and cancer (Genome Biol 2007;8:R189).

Dr. Steve Cole, an associate professor of medicine, and colleagues studied 14 elderly patients, six of them chronically lonely. The differences they observed in gene expression between the two groups were independent of other known risk factors, such as health status, age, weight, and medication use.

"We found that changes in immune cell gene expression were specifically linked to the subjective experience of social distance," Cole said.

Researchers hope this "transcriptional fingerprint" can be used as a biomarker to interventions designed to reduce the impact of loneliness on health.