Washington, June 11 (IANS): Short sleep duration and frequent snoring during pre-diagnostic stage are associated with significantly poorer cancer-specific survival, particularly among women with breast cancer, says a study.

The results may motivate cancer patients to improve their sleep patterns.

"Our results suggest that sleep duration is important for breast cancer survival, particularly in women who snore," said lead author Amanda Phipps, assistant professor of epidemiology, at the University of Washington in Seattle.

The study was outlined online in the journal Sleep.

The study group comprised of 21,230 women diagnosed with a first primary invasive cancer during follow-up from the Women's Health Initiative (WHI).

Participants provided information on several sleep attributes at study baseline, including sleep duration, snoring and components of the WHI Insomnia Rating Scale.

Analyses were adjusted for age at enrollment, study arm, cancer site, marital status, household income, smoking, physical activity and time-lag between baseline data collection and cancer diagnosis.

Short sleep duration and frequent snoring were linked to significantly poorer breast cancer-specific survival, found the study.