Editing Insomnia (section)

=== Poor sleep quality ===
Poor sleep quality can occur as a result of, for example, [[restless legs]], [[sleep apnea]], or [[major depression]]. Poor sleep quality is defined as the individual not reaching [[Slow-wave sleep|stage 3]] or delta sleep, which has restorative properties.<ref>{{Cite web |url=https://sleepfoundation.org/how-sleep-works/what-happens-when-you-sleep |title=What Happens When You Sleep? |date=22 December 2009 |access-date=24 February 2017 |url-status=live |archive-url=https://web.archive.org/web/20170305005723/https://sleepfoundation.org/how-sleep-works/what-happens-when-you-sleep |archive-date=5 March 2017 }}</ref>

Major depression leads to alterations in the function of the [[hypothalamic–pituitary–adrenal axis]], causing excessive release of [[cortisol]], which can lead to poor sleep quality.

Nocturnal [[polyuria]], excessive night-time urination, can also result in a poor quality of sleep.<ref>{{cite journal | vauthors = Adler CH, Thorpy MJ | s2cid = 24024570 | title = Sleep issues in Parkinson's disease | journal = Neurology | volume = 64 | issue = 12 Suppl 3 | pages = S12–20 | date = June 2005 | pmid = 15994219 | doi = 10.1212/WNL.64.12_suppl_3.S12 }}</ref>