According to one meta-analysis, the mean prevalence rate for North America and Western Europe is estimated to be 14.5±8.0%. Specifically in the United States, the prevalence of restless leg syndrome is estimated to be between 5 and 15.7% when using strict diagnostic criteria. RLS is over 35% more prevalent in American women than their male counterparts.
A systematic review found that traumatic childhood experiences (such as family conflict or sexual trauma) significantly increases the risk for a number of sleep disorders in adulthood, including sleep apnea, narcolepsy, and insomnia. It is currently unclear whether or not moderate alcohol consumption increases the risk of obstructive sleep apnea.
A catch-all term for the inability to fall or stay asleep, sleeplessness is -- as sufferers know -- a very serious problem. It's sleeplessness whenever something, whether it's physical pain, anxiety, or an underlying condition, prevents you from falling asleep within a reasonable amount of time or staying asleep long enough to achieve a good night's sleep.