Editing Snoring (section)

==Causes==
Snoring is often considered according to the location (level) of structure that is causing the obstruction and vibration. However, the sites causing the snoring vary from one person to the next, and the same individual may have multiple different sites which are contributing to the problem.<ref name="Dhingra2017" />

===Nasal cavity===
[[File:Illu nose nasal cavities.jpg|thumb|right|alt=Sagittal section of nasal cavity (nose). |Sagittal section of nasal cavity (nose).]]
While it is generally not possible for the rigidly supported structures inside the nose to vibrate, the patency of the nasal airway is important in the development of snoring.<ref name="Stuck2019" /> The [[nasal cavity]] causes over 50% of the total airway resistance, particularly at the [[internal nasal valve|internal]] and [[external nasal valve]]s.<ref name="Yap2022" /> The internal nasal valve is located approximately 1.5 cm from the nostril and constitutes the narrowest part of the upper airway.<ref name="Kiyohara2016">{{cite journal |last1=Kiyohara |first1=N |last2=Badger |first2=C |last3=Tjoa |first3=T |last4=Wong |first4=B |title=A Comparison of Over-the-Counter Mechanical Nasal Dilators: A Systematic Review. |journal=JAMA Facial Plastic Surgery |date=1 September 2016 |volume=18 |issue=5 |pages=385–9 |doi=10.1001/jamafacial.2016.0291 |pmid=27367589}}</ref> The external nasal valve is the tissue immediately around the nostril. [[Nasal valve collapse]] refers to weakening or narrowing of the supporting cartilage at the nasal valves. As per the [[Hagen–Poiseuille equation]], a minimal reduction in the diameter of a tube (in this case the nasal airway) results in an exponential change in airflow.<ref name="Casale2023">{{cite journal |last1=Casale |first1=M |last2=Moffa |first2=A |last3=Giorgi |first3=L |last4=Pierri |first4=M |last5=Lugo |first5=R |last6=Jacobowitz |first6=O |last7=Baptista |first7=P |title=Could the use of a new novel bipolar radiofrequency device (Aerin) improve nasal valve collapse? A systematic review and meta-analysis. |journal=Journal of otolaryngology - head & neck surgery = le Journal d'oto-rhino-laryngologie et de chirurgie cervico-faciale |date=22 June 2023 |volume=52 |issue=1 |pages=42 |doi=10.1186/s40463-023-00644-7 |doi-access=free |pmid=37349806 |pmc=10286448}}</ref> Nasal valve collapse is a cause of snoring.<ref name="Dhingra2017" /><ref name="Casale2023" />

[[Nasal congestion]] (nasal obstruction) reduces sleep quality.<ref name="Yap2022" /> Common reasons for nasal obstruction are [[allergic rhinitis]] and [[nonallergic rhinitis]].<ref name="Yap2022" /> [[Nasal septum deviation]] and [[inferior turbinate]] hypertrophy (enlargement) are present in almost all cases of snoring and obstructive sleep apnea.<ref name="Yap2022" /> Masses in the nasal cavity such as [[nasal polyp]]s or [[Paranasal sinus and nasal cavity cancer|tumors]] may also cause snoring.<ref name="Deenadayal2022" /><ref name="Dhingra2017" />

===Adenotonsillar hypertrophy===
[[Adenoid hypertrophy]] (enlargement of the [[adenoid]] tonsil) and [[Palatine_tonsil#Tonsillar_hypertrophy|tonsillar hypertrophy]] (enlargement of the [[palatine tonsil]]s) is associated with snoring and obstructive sleep apnea,<ref name="Sakarya2017">{{cite journal |last1=Sakarya |first1=EU |last2=Bayar Muluk |first2=N |last3=Sakalar |first3=EG |last4=Senturk |first4=M |last5=Aricigil |first5=M |last6=Bafaqeeh |first6=SA |last7=Cingi |first7=C |title=Use of intranasal corticosteroids in adenotonsillar hypertrophy. |journal=The Journal of Laryngology and Otology |date=May 2017 |volume=131 |issue=5 |pages=384–390 |doi=10.1017/S0022215117000408 |pmid=28238295}}</ref><ref name="ICSD-3" /><ref name="Chawla2015" /> especially in children since the tonsils are larger at younger ages. Adenotonsillar hypertrophy is the most common cause of snoring in children.<ref name="Dhingra2017" />

===Mouth===
Dental problems may be conditions associated with snoring rather than direct causes. Examples include [[malocclusion]], crowding of upper teeth, a narrow [[palate]],<ref name="Chawla2015" /> and a [[high-arched palate]]. Narrow palate and high-arched palate create a predisposition to chronic nasal obstruction.<ref name="Yap2022" />

===Mouth breathing===
[[Mouth breathing]] frequently accompanies snoring as one of main features of sleep-related breathing disorders (including primary snoring, upper airway resistance syndrome, and obstructive sleep apnea).<ref name="Pacheco2015">{{cite journal |last1=Pacheco |first1=MC |last2=Casagrande |first2=CF |last3=Teixeira |first3=LP |last4=Finck |first4=NS |last5=de Araújo |first5=MT |title=Guidelines proposal for clinical recognition of mouth breathing children. |journal=Dental Press Journal of Orthodontics |date=July 2015 |volume=20 |issue=4 |pages=39–44 |doi=10.1590/2176-9451.20.4.039-044.oar |pmid=26352843 |pmc=4593528}}</ref> In one study, 18% of people with mouth breathing reported awareness of snoring.<ref name="Pacheco2015" /> 

===Retrognathia===
[[Retrognathia]] (receded lower jaw) is more common in obstructive sleep apnea than in primary snoring.<ref name="Yap2022" /> [[Micrognathia]] (small jaw size) is also linked to snoring.<ref name="Chawla2015" />

===Pharynx===
The muscles of the pharynx relax during sleep, causing partial airway obstruction.<ref name="Dhingra2017">{{cite book |last1=Dhingra |first1=PL |last2=Dhingra |first2=S |title=Diseases of Ear, Nose and Throat & Head and Neck Surgery |date=7 October 2017 |publisher=Elsevier Health Sciences |isbn=978-81-312-4939-0 |pages=313 |language=en}}</ref> The oropharynx is a common site which causes snoring noises.<ref name="Stuck2019" />

===Tongue===
When sleeping on the back, gravity pulls the tongue backwards and may obstruct the airway.<ref name="mayo">{{cite web |url=http://www.mayoclinic.org/diseases-conditions/snoring/basics/causes/con-20031874 |title=Snoring Causes |date=26 April 2015 |website=Mayo Clinic |access-date=15 June 2016}}</ref> An enlarged tongue, termed [[macroglossia]], is a potential cause for snoring.<ref name="Dhingra2017" /> Obesity may result in increased tongue size.<ref name="Yaremchuk2020" /> The base of the tongue may be enlarged and cause snoring, e.g. because of a [[Oral cancer|tumor]].<ref name="Dhingra2017" />

===Larynx and laryngopharynx===
Problems within the [[larynx]] ("voice box") and [[laryngopharynx]] may cause snoring, such as [[laryngeal stenosis]] or an omega-shaped [[epiglottis]].<ref name="Dhingra2017" /> 

===Obstructive sleep apnea===
Snoring is one of the cardinal symptoms of obstructive sleep apnea.<ref name="ICSD-3" /> People who snore are five times more likely to have obstructive sleep apnea compared to those who don't snore.<ref name="Yap2022" /> Snoring is common in upper airways resistance syndrome, and obstructive sleep apnea is almost always associated with snoring.<ref name="Deenadayal2022" />

===Obesity===
Being [[obesity|obese]] or [[overweight]] increases the amount of [[Adipose tissue|fat]] around the throat. It is not just body mass index that is important, but the circumference of the neck (e.g., collar size more than {{Convert|42|cm|in|abbr=on}})<ref name="Dhingra2017" /> and the size of the tongue.<ref name="Yaremchuk2020" /> [[Obesity hypoventilation syndrome]] also involves snoring.<ref name="Deenadayal2022">{{cite book |last1=Deenadayal |first1=DS |last2=Bommakanti |first2=V |title=Management of Snoring and Obstructive Sleep Apnea: A Practical Guide |date=4 January 2022 |publisher=Springer Nature |isbn=978-981-16-6620-9 |language=en |pages= 1, 4, 14, 29, 34, 44, 50, 51, 55, 56, 64, 98}}</ref>

===Alcohol===
[[Alcohol (drug)|Alcohol]] causes muscle relaxation via its [[depressant]] effect on the [[central nervous system]]. This muscle relaxation seems to be more pronounced for the tongue,<ref name="Yaremchuk2020" /> which may then be more prone to obstruct the airway. 

===Muscle relaxants===
Medications that cause muscle relaxation, such as [[sedative]]s and [[hypnotic]]s, may cause snoring or make it worse. One example is [[diphenhydramine]].<ref name="Yaremchuk2020" />

===Diet===
Magnesium is a [[micronutrient]] which may have a role in maintaining [[circadian rhythm]] and sleep quality.<ref name="Arab2024" /> There may be a connection between higher magnesium intake and sleep quality, which includes factors such as snoring, daytime sleepiness, and sleep duration. One study supported this connection. Another study showed that 332.5 mg/day magnesium did not have any effect on sleep symptoms such as snoring and sleepiness.<ref name="Arab2024">{{cite journal |last1=Arab |first1=A |last2=Rafie |first2=N |last3=Amani |first3=R |last4=Shirani |first4=F |title=The Role of Magnesium in Sleep Health: a Systematic Review of Available Literature. |journal=Biological Trace Element Research |date=January 2023 |volume=201 |issue=1 |pages=121–128 |doi=10.1007/s12011-022-03162-1 |pmid=35184264|bibcode=2023BTER..201..121A }}</ref>

===Pregnancy===
Sometimes snoring starts during [[pregnancy]].<ref name="ICSD-3" /><ref name="Jung2022">{{cite journal |last1=Jung |first1=E |last2=Romero |first2=R |last3=Yeo |first3=L |last4=Gomez-Lopez |first4=N |last5=Chaemsaithong |first5=P |last6=Jaovisidha |first6=A |last7=Gotsch |first7=F |last8=Erez |first8=O |title=The etiology of preeclampsia. |journal=American Journal of Obstetrics and Gynecology |date=February 2022 |volume=226 |issue=2S |pages=S844–S866 |doi=10.1016/j.ajog.2021.11.1356 |pmid=35177222 |pmc=8988238}}</ref>

===Hereditary factors===
Some people have a genetic predisposition to snoring, a proportion of which may be mediated through other heritable lifestyle factors such as body mass index, smoking and alcohol consumption.<ref name=":0">{{cite journal | vauthors = Campos AI, García-Marín LM, Byrne EM, Martin NG, Cuéllar-Partida G, Rentería ME | title = Insights into the aetiology of snoring from observational and genetic investigations in the UK Biobank | journal = Nature Communications | volume = 11 | issue = 1 | pages = 817 | date = February 2020 | pmid = 32060260 | pmc = 7021827 | doi = 10.1038/s41467-020-14625-1 | bibcode = 2020NatCo..11..817C }}</ref> The [[DLEU1]] gene (part of BCMS) has been linked to snoring.<ref>{{cite journal |last1=Campos |first1=AI |last2=Ingold |first2=N |last3=Huang |first3=Y |last4=Mitchell |first4=BL |last5=Kho |first5=PF |last6=Han |first6=X |last7=García-Marín |first7=LM |last8=Ong |first8=JS |last9=23andMe Research Team |last10=Law |first10=MH |last11=Yokoyama |first11=JS |last12=Martin |first12=NG |last13=Dong |first13=X |last14=Cuellar-Partida |first14=G |last15=MacGregor |first15=S |last16=Aslibekyan |first16=S |last17=Rentería |first17=ME |title=Discovery of genomic loci associated with sleep apnea risk through multi-trait GWAS analysis with snoring. |journal=Sleep |date=9 March 2023 |volume=46 |issue=3 |doi=10.1093/sleep/zsac308 |pmid=36525587 |pmc=9995783}}</ref>