Snoring in bed may be annoying for your sleeping partner, but new research suggests that it may be linked to hyperactivity and misbehaviour in children too. A study, published in the journal Pediatrics, found that one-third of two- and three-year-olds who snore were considered to be at risk of a behavioural disorder. Snoring doesn't necessarily cause these disorders, but it does seem to be linked to them in some way. "The strongest predictors of persistent snoring were lower socioeconomic status and the absence or shorter duration of breastfeeding," said Dr Dean Beebe of Cincinnati Children's Hospital Medical Center, the author of the study. "This would suggest that doctors routinely screen for and track snoring, especially in children from poorer families, and refer loudly-snoring children for follow-up care." He went on to say that occasional snoring is normal - it's when it persists over a sustained period of time that parents should worry. It is also often associated with sleep apnea, a condition characterised by abnormal pauses in breathing, which can interfere with restful sleep and can have more serious consequences.