Men who have sleep problems, including difficulty falling asleep and staying asleep, have up to a twofold increased risk for prostate cancer, according to a new study published Tuesday in the U.S. journal Cancer Epidemiology, Biomarkers & Prevention.

"Sleep problems are very common in modern society and can have adverse health consequences," said lead author Lara G. Sigurdardottir at the University of Iceland in Reykjavik. "Women with sleep disruption have consistently been reported to be at an increased risk for breast cancer, but less is known about the potential role of sleep problems in prostate cancer."

Sigurdardottir's study included more than 2,100 men, aged 67 to 96, in Iceland. They were asked if they took medications to help them sleep, had trouble falling asleep or woke up during nights or early in the morning and had difficulty going back to sleep.

The researchers found 14.4 percent reported severe or very severe sleep problems. None of the participants had prostate cancer at study entry. They followed the participants for five years, and during this period, 6.4 percent were diagnosed with prostate cancer.

After adjusting for age, they found that compared with men who reported no problems with sleeping, the risk for prostate cancer increased proportionately with reported severity of problems falling and staying asleep, from 1.6-fold to 2.1-fold.

"If our results are confirmed with further studies, sleep may become a potential target for intervention to reduce the risk for prostate cancer," said Sigurdardottir.

Source: Xinhuanet