There was increase in fundamental frequency, maximum phonation time and self-reference voice-related quality of life.

Results: Maximal phonation time was shorter in groups A and B compared with that of controls.

The hypothesis was that the reduced maximum phonation time in people with obesity would be corrected after surgery due to weight loss.

Two hours after the intake of zolpidem, improvement of all the parameters tested, with the exception of the maximum phonation time, was observed.

There was an increase in maximal phonation time after surgery (Group B); however, the difference was not significant when compared with that in group A.