<prompt> True about obstructive sleep apnea are all exceptFemales affected more than malesCommonly associated with hypeensionDay time sleepiness is seen5 episodes of apnea per hour  <response>: Obstructive sleep apnea is defined as the coexistence of unexplained excessive daytime sleepiness with at least 5 obstructed breathing events apnea or hypopnea per hour of sleep.Male sex and middle age40-65 years are predisposing factors.It is associated with elevated 24-h mean blood pressure.The increase is greater in those with recurrent nocturnal hypoxemia,is at least 4-5 mmHg and may be as great as 10 mmHg in those with 20 aerial oxygen desaturations per hour of sleep.This rise probably results from a combination of surges in blood pressure accompanying each arousal at apneahypopnea termination and from the associated 24-h increases in sympathetic tone. Ref:Harrisons medicine-18th edition,page no:2187. 