The symptoms and signs of upper airway resistance syndrome: a link to the functional somatic syndromes, 2003, Gold et al.

[nataliezzz]

The symptoms and signs of upper airway resistance syndrome: a link to the functional somatic syndromes
Avram R Gold, Francis Dipalo, Morris S Gold, Daniel O'Hearn
https://www.researchgate.net/publication/10950246_The_symptoms_and_signs_of_upper_airway_resistance_syndrome_a_link_to_the_functional_somatic_syndromes (PDF avaiable)

Study objectives: The functional somatic syndromes are associated with a variety of symptoms/signs of uncertain etiology. We determined the prevalence of several of those symptoms/signs in patients with sleep-disordered breathing and examined the relationship between the prevalence of the symptoms/signs and the severity of sleep-disordered breathing.

Design: A descriptive study without intervention.

Setting: A university sleep-disorders center located in a suburban setting.

Patients or participants: Three groups of 25 consecutively collected patients with sleep-disordered breathing. Groups varied in their apnea hypopnea indexes (AHIs) as follows: upper airway resistance syndrome (UARS) [AHI < 10/h), mild-to-moderate obstructive sleep apnea/hypopnea (OSA/H) [AHI >or= 10 to < 40/h), and moderate-to-severe OSA/H (AHI >or= 40/h).

Measurements and results: Patients underwent comprehensive medical histories, physical examinations, and full-night polysomnography. The diagnosis of UARS included quantitative measurement of inspiratory airflow and inspiratory effort with demonstration of inspiratory flow limitation. The percentage of women among the patients with sleep-disordered breathing (p = 0.001) and the prevalence of sleep-onset insomnia (p = 0.04), headaches (p = 0.01), irritable bowel syndrome (p = 0.01), and alpha-delta sleep (p = 0.01) was correlated with decreasing severity of AHI group.

Conclusions: We conclude that patients with UARS, mild-to-moderate OSA/H and moderate-to-severe OSA/H differ in their presenting symptoms/signs. The symptoms/signs of UARS closely resemble those of the functional somatic syndromes.

 

[nataliezzz]

The study is a prospective examination of the prevalence of a variety of symptoms/signs in 75 patients with UARS and OSA/H (25 consecutive patients with sleep-disordered breathing at each of three levels of severity). All of the patients were referred to the SUNY Sleep Disorders Center Medicine because of a clinical suspicion of sleep-disordered breathing. Patients with fibromyalgia referred for evaluation of sleep-disordered breathing were excluded because they would be expected to have the symptoms of the functional somatic syndromes.

UARS was diagnosed was made based on: AHI<10, excessive daytime sleepiness/fatigue, and inspiratory flow limitation during non-REM sleep.

One potential explanation for the inverse relationship observed between the AHI and some of these symptoms like sleep-onset insomnia, headaches, and IBS (as well as alpha-delta sleep) in sleep-disordered breathing patients is that as the frequency of apneas (complete/near complete cessation of airflow) increases, there is less exposure to inspiratory flow limitation (the proposed stressor in Dr. Gold's theory of UARS): "while apnea isolates the nasal airway from the hypopharynx and results in nasal pressure that is equal to atmospheric pressure, hypopnea, and to a greater extent, snoring [or inaudible inspiratory flow limitation] leads to prolonged decreases in nasal pressure." (from this article).

This could also help explain the predominance of mild sleep-disordered breathing (predominance of hypopnea and milder inspiratory flow limitation rather than apnea) seen in patients with disorders like fibromyalgia; for example, in the study below, where polysomnography (PSG) was offered to consecutive female fibromyalgia patients at a rheumatology clinic (23 [40%] underwent PSG, with 14 of those 23 having complaints related to sleep; 19/23 [83%] had an AHI >15; unspecified how many had milder OSA but it looks like 100% had OSA based on the graph), mean apnea index was 0.83 and mean hypopnea index was 30.6 (inspiratory flow limitation is present during hypopnea, but not apnea).

Sleep-Disordered Breathing Among Women With Fibromyalgia Syndrome, 2006, Shah et al

Elevated rates of temporomandibular joint disorders (TMJD) in individuals with disorders like fibromyalgia could be partly explained by high rates of bruxism in sleep-disordered breathing patients (as well as other contributing factors like increased pain sensitivity).

Thread here on UARS/OSA and insomnia: Sleep-disordered breathing (UARS/OSA) and chronic insomnia

 

[nataliezzz]

Re: alpha-delta sleep:

Alpha-delta sleep was present in six of our patients with UARS (8.9 ± 8.5% of total sleep time), in three of our patients with mild-to-moderate OSA/H (13.7 ± 7.4% of total sleep time), and in none of our patients with moderate-to-severe OSA/H. In patients with alpha-delta sleep, the finding was present in all slow-wave sleep observed during polysomnography. Furthermore, each patient with alpha-delta sleep during full night polysomnography also had the finding during the CPAP study. Each patient without alpha-delta sleep during polysomnography did not display alpha-delta sleep during the CPAP study.

See a case report of fibromyalgia cure with treatment of OSA where alpha-delta sleep disappeared along with symptoms here:
Resolution of fibromyalgia by controlling obstructive sleep apnea with a mandibular advancement device, 2021, Vantine et al.