Mr Morris is a 48 year old finance director and presents to the GP to discuss his snoring as his wife is increasingly bothered by it. He has a BMI of 33, drinks 30 units of alcohol a week, stopped smoking last year and frequently dines out with clients each week. A diagnosis of Obstructive Sleep Apnoea Syndrome (OSAS) is suspected.

Which one of the following symptoms is least associated with OSAS?