...that benzodiazepines like Ambien, Valium, Ativan and Xanax suppress cortisol’s natural increase in the early morning preventing restorative sleep?

Patients who take these medications will get a good number of hours of sleep, but will never wake up “refreshed.”  Patients who take this type of sleep aide are more prone to develop dementia over their lifetime.  This is because benzodiazepines have a permanent effect on the GABA brain receptors that are important for sleep.