No, you can have OSAS without snoring according ICDS-3 criteria!

Cordially, Horst

Snoring is not a requirement although it is true that most people with OSA snore. By the way only about 50% of people who snore have OSA and not all people with OSA are obese.

Thank you both for your comments. Could hypoxia (SA02

Hi Amy

REM-related hypoventilation and hypoxemia can occur not only due to upper airway muscle hypotonia (in combination with a collapsible airway) but also via a reduced ventilatory drive regardless of airway obstruction (e.g. Douglas N et al Thorax 1982). Both elements may be acting together. 

For severe REM-related hypoxemia to occur, the degree of hypoventilation could be large (e.g. neuromuscular disease), there may be an element of lung disease (and ventilation-perfusion mismatch predisposing to hypoxemia), or both. Patients with COPD have been observed to have REM-related hypoxemia, presumably as even a small amount of hypoventilation in REM causes a large drop in oxygen saturation in these susceptible patients. You could work out the cause of hypoxemia (hypoventilation versus lung disease components) by measuring PCO2. 

REM-related hypoventilation that is due to reduced ventilatory drive rather than to upper-airway dilator muscle hypotonia is unlikely to improve much with CPAP. (However CPAP could potentially improve ventilation-perfusion matching and may improve the hypoxemia.) Other options for treatment that clinicians may consider include bi-level PAP or supplemental oxygen. 

Hope this helps

Scott

Thank you Scott. That helps immensely. I really appreciate the citation too.

Amy - is the patient extremely obese BMI > 40?  What sleeping position was he/she in when they hypoventilated during REM?  Are you confident in the oximeter reading that presumably conflicted with the airflow and effort signals? 

Daniel,

The patient is not obese (BI

Was she taking opiate medication?

No, she has hashimoto's disease (107 mcg/d levoxylthyroxine - FT3, FT, TSH normal)  and takes 10 mg of Levrix (hay fever medication) per day. Also experiences night sweats, orthostatic hypotension, and erratic (lower than normal) body temp. 

No, you can have OSA without snoring in patients with uvulopalatopharyngoplasty. 

Thanks MA, but wouldn't the uvulopalatopharyngoplasty be more pertinent to a mouth breather than a nose breather? Given the patient breaths thru the nose, and has hashimoto's disease, would it be more probable that thyroid tissue could be causing the obstruction? Her Right lobe has 3.5 times the volume of the left lobe (RL volume 2.9 ml and length 4cm; LL volume 0.8 ml and length 2.5 cm).

Hello Amy,

Obstructive sleep apnea syndrome (OSAS) is evaluated using clinical history, physical examination,  and nocturnal polysomnography  to determine the presence of daytime symptoms, apnea and hypopnea, hypoxemia, arousals, respiratory effort, and any disturbances in sleep architecture. Polysomnographic features of OSA include reduced or absent airflow with obvious chest or abdominal  motion, which is an indicator of an attempt by the patient to breath. Hypoxemia is demonstrated by a reduction in SPO2 during episodes of apnea or hypopnea.

OSAS can exist in the patients with autoimmune thyroid disorder even if they are euthyroid. The proposed mechanisms  to explain this coexistence include mucoprotein deposition in the upper airway, decreased neural output to the upper airway musculature, an upper airway obstruction related to neuromuscular pathology, and abnormalities in ventilatory control caused by autoimmune thyroiditis .

Some references:

Avidan AY, Zee PC. Handbook of sleep medicine, 2011 Lippincott Williams @Wilkins pp14-29

Reynolds H, Strey G.An uncommon presentation of Hashimoto's disease. Aust J Rural Health. 2013 Feb;21(1):50-2.

Erden S, Cagatay T, Buyukozturk S, Kiyan E, Cuhadaroglu C.Hashimoto thyroiditis and obstructive sleep apnea syndrome: is there any relation between them? Eur J Med Res. 2004 Dec 22;9(12):570-2.

Best wishes,

Tatyana

Awesome Response! Thank you so much for the references.

Dear Amy Lovatt

As a Pediatrician i have seen a few cases when the child had severe osas and did not snore. Usually , snoring occurs in mouth breathing, and these patients although had grade four tonsils, they did not have adenoid enlargement. So, they were nose breathers during the night, but had apneia mainly when they were in back position to sleep. And polysomno demonstrated severe oxygen desaturation.  At least in children nose obstruction is what makes them snore.

Thank you very much Jose. I just noticed your article with regards to the hypothalamus-pituitary-thyroid axis. This is something of much interest to me. In the case with the person who is experiencing REM related hypopnea (sleeping on sides predominately, and through the nose), this was observed for a sleep study to diagnose narcolepsy. The second sleep study will soon follow after adjustment to APAP. However, this individual also has Hashimoto's, FT4/FT3 mid normal due to medication, and TSH low. Also, the person is experiencing variable body temperature (increases in the night - night sweats) and decreases in the day, especially after exercise and when tired). It seems to me that the sleep issues are very much connected to the endocrine system; however, the literature is very sparse here.

Hashimto's and sleep apnea :Just curious--has the patient been documented to have OSA and NOT central sleep apnea at all? I did not see all the sleep lab data (but may have missed it) Both types of apnea can occur. Some references late to the game:  (most of them are older references)

The last article turns things on their head--suggesting that OSA can cause autoimmune problems--e.g. CAUSE Hashimoto's. Interesting and, if you go there you can follow it's citations too. I don't know if the methodology was tight but fun to read!

Respiration. 2003 May-Jun;70(3):320-7.

Sleep apnea syndrome in endocrine diseases.

Bottini P1, Tantucci C.

Am Rev Respir Dis. 1983 Apr;127(4):504-7.

Central sleep apnea in hypothyroidism.

Millman RP, Bevilacqua J, Peterson DD, Pack AI.

Am J Med. 1988 Dec;85(6):775-9.

Sleep apnea and hypothyroidism: mechanisms and management.

Grunstein RR1, Sullivan CE.

Sleep Breath. 2015 Mar;19(1):85-9. doi: 10.1007/s11325-014-0966-0. Epub 2014 Mar 13.

Relationship between sleep apnea and thyroid function.

Takeuchi S1, Kitamura T, Ohbuchi T, Koizumi H, Takahashi R, Hohchi N, Suzuki H.

The association between severity of obstructive sleep apnea and prevalence of Hashimoto’s thyroiditis

Nujen Colak Bozkurt1), Basak Karbek1), Erman Cakal1), Hikmet Firat2), Mustafa Ozbek1), Tuncay Delibasi1)

1) Department of Endocrinology and Metabolism, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara 06115, Turkey 2) Department of Chest Medicine and Sleep Disorders Center, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara 06115, Turkey