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Breathing-Related Sleep Disorder
Updated: Jul 17, 2008
Introduction
Background
The term breathing-related sleep disorder refers to a spectrum of breathing anomalies ranging from chronic or habitual snoring to upper airway resistance syndrome (UARS) to frank obstructive sleep apnea (OSA) or, in some cases, obesity hypoventilation syndrome (OHS).
Data from the Wisconsin sleep cohort study of patients without obvious barriers to health care access estimate that 93% of women and 82% of men with moderate-to-severe sleep apnea were undiagnosed.1 Significant cardiovascular morbidity (including systemic hypertension and congestive heart failure) as well as increased mortality rates have been associated with both OSA and OHS. While large-scale studies of the prevalence of sleep-disordered breathing in children are lacking, Guilleminault et al report estimates of 5-6% and raise concerns about the impact of the obesity epidemic on sleep in children.2
The aim of this article is to increase the reader's awareness of the importance of sleep-disordered breathing in daily practice.
For related information, see Medscape's Insomnia and Sleep Health Resource Center.
Pathophysiology
Complex interactions among the central and peripheral nervous systems, upper airway musculature, and neurotransmitters may result in partial or complete collapse of a portion or portions of the upper airway. Basic factors, such as airway anatomy (eg, adenotonsillar hypertrophy), nasal obstruction, presence and distribution of body fat, and muscle tone, may contribute, alone or in combination, to the presence and severity of this disorder. Recent data suggest that the primary defect is an anatomically small or collapsible pharyngeal airway in combination with a sleep-related fall in upper airway muscular tone.
Patients with neuromuscular disease have additional risk factors that may predispose them to sleep-disordered breathing. These include CNS involvement, chest wall deformity with restrictive lung disease, diaphragmatic weakness, increased upper airway resistance, and impaired respiratory chemosensitivity.
Frequency
United States
According to estimates, at least 2-4% of the adult population experience sleep-related breathing disorders.3,4 In a study by Young and associates, 24% of men and 9% of women aged 30-60 years were reported to have sleep-disordered breathing.1 Caples et al reviewed pooled data from 4 large prevalence studies on OSA and found that 20% of adult Caucasians with BMI between 25 and 28 kg/m2 had an apnea hypopnea index (AHI) of 5 or greater and that approximately 6% of these same patients had AHIs of 15 or greater.5
Patients with neuromuscular diseases may have sleep-disordered breathing. Duchenne muscular dystrophy (DMD), amyotrophic lateral sclerosis, postpolio syndrome, and myasthenia gravis are among those with increased incidence of sleep-disordered breathing.
Prevalence studies in the elderly population show significantly higher rates, with the rate for elderly men reported as 28-67% and the rate for elderly women as 20-54%. In the subset of patients with severe OSA, men have an 8-fold increased frequency. Prevalence rates in children are estimated to be 5-6%.2
Mortality/Morbidity
Obesity, advanced age, and snoring have been found to be important factors in the progression of sleep-disordered breathing.
Morbidity with OSA falls into 2 major categories, as follows:
- Neuropsychiatric or psychosocial: This includes excessive daytime sleepiness, poor concentration and memory, decreased performance, irritability, depression, and disturbed social relationships. This population has a significantly increased risk of motor vehicle accidents, with reports of a 7-fold increased risk in patients with an AHI greater than 5.
- Cardiovascular: Systemic hypertension occurs in 45-90% of patients with OSA. Pulmonary hypertension has been reported in 15-20%.6
Children with sleep-disordered breathing have an increased use of healthcare services (2.6 fold increase) with deficits in school performance and IQ, as well as a higher prevalence of neuropsychiatric disorders.7
Race
Comparison date between African American and Caucasian adults when corrected for BMI suggest that prevalence of sleep-disordered breathing in African Americans is at least equal to and may in fact exceed that of their Caucasian peers.
Sex
- Male sex appears to be related to a significant increase in the prevalence of sleep-disordered breathing, presumably because of hormonal influences. Testosterone in particular is associated with increased severity of sleep-related breathing disorders. In the subset of patients with severe obstructive sleep apnea, men outnumber women by eight fold.
- Sex hormones play a role in the modulation of upper airway musculature. In adults, the prevalence in males exceeds that of females by 3 fold in middle age. In women with OSA, apneas tend to cluster during REM sleep. In men with OSA, apneas predominate in the supine position.
- No sex difference exists before puberty, and, after menopause, the differences again become small. The increase in frequency of sleep-related breathing disorders in women who are postmenopausal may be related to decreases in progesterone levels.
Age
- In children, those born prematurely have been found to be 3-5 times more likely to have sleep-disordered breathing compared with their full-term counterparts. Childhood OSA has its peak incidence between ages 2-8 years, corresponding to the time when tonsils and adenoids are the largest in relationship to upper airway size. Prevalence for habitual snoring in school age children is estimated to be 12-20%.7
- Both snoring and sleep-related breathing disorders increase in frequency with advancing age, at least until age 60 years. Older persons exhibit both central and obstructive apnea. The pattern of apnea in older persons having AHI greater than 5 resembles typical sleep apnea in regard to duration and degree of desaturation. However, the effect on general health in elderly people with OSA appears to be minimal.
- In elderly people, little to no relationship seems to exist between sleep apnea and typical risk factors such as excess weight and increased airway resistance. The mechanisms underlying sleep apnea in elderly people are purportedly be different, and they may reflect a gradual increase in sleep instability, which results in both central apnea and OSA.
Clinical
Physical
- General characteristics: Obesity and craniofacial dysmorphology are important features to identify. Micrognathia, retrognathia, maxillary hypoplasia, cleft palate, and macroglossia are among the important initial features to assess. The image below shows a photograph of a patient with significant retrognathia that contributed to his OSA.
Breathing-related sleep disorder. Significant retrognathia that contributed to this patient's obstructive sleep apnea (OSA).
- Mental status: The Mental Status Examination should be tailored to the individual patient, with particular attention to affect because depression is not an uncommon comorbidity in people with sleep deprivation. In patients with neuropsychiatric disease, this evaluation is more extensive. In addition to insomnia, patients with depressed mood may have poor appetites, resulting in weight gain or weight loss, fatigue, psychomotor retardation or agitation, difficulty concentrating, or poor memory. Suicidal ideation and actual attempts may occur, especially during the recovery phase.
- Blood pressure: Systemic hypertension occurs in approximately 45-90 % of patients with OSA.6 While diagnostic upper limits may vary somewhat by study site, most agree that hypertension exists when systolic blood pressure is documented repeatedly (ie, on 2 or more visits) as greater than 140 mm Hg or when the diastolic value equals or exceeds 90 mm Hg on 2 or more visits. Patients with hypertension have an increased incidence of OSA (ie, up to 30%6 ), and questions about sleep should be included in the workup of patients with hypertension.
- Height and weight (BMI): BMI greater than 28 is frequently associated with OSA.
- Collar size: Collar size is measured at the level of the cricothyroid membrane and is another parameter associated with predicting risk for OSA. In snoring male patients with collar sizes greater than 17 inches, the prevalence of OSA is 30%. Women with collar sizes greater than 15 inches have also been found to be at increased risk.
- Nasal examination: The nasal examination is critical in identifying potential anatomic sites of obstruction such as a deviated septum, enlarged adenoids, swollen nasal turbinates, polyps, or other mass lesions. The nasal examination is often conducted using a flexible fiberoptic nasopharyngoscope. In addition to the potential diagnostic value of this procedure, a patent nasopharyngeal airway is necessary if nasal continuous positive airway pressure (n-CPAP) is considered as a treatment option in OSA.
- Craniodentofacial examination: In addition to the features described above (eg, retrognathia, micrognathia, macroglossia), mandibular alignment, dental occlusion, and cephalometric data are often helpful.
- Oropharynx: A variety of anatomic feature can have an impact on airflow limitation at this level, including large tonsils, long soft palate, large uvula, pharyngeal flap, posterior pharyngeal stenosis and scarring, redundant fold, and tumors. The relationship of the tongue, palate, and posterior pharyngeal wall can cause posterior pharyngeal crowding and predisposition to OSA.
- Neck: Fat distribution in this area can compromise airflow during sleep when muscle tone is reduced, especially during REM sleep. Masses, including significant lymphadenopathy, should be noted.
Causes
OSA results from airflow obstruction secondary to upper airway collapse or anatomic airway obstruction. In adults, the obstruction typically occurs at the level of the uvula/soft palate or tongue. The interrelationship of age, sex, obesity, and craniofacial size and dynamics is still poorly understood.
More on Breathing-Related Sleep Disorder |
 Overview: Breathing-Related Sleep Disorder |
| Differential Diagnoses & Workup: Breathing-Related Sleep Disorder |
| Treatment & Medication: Breathing-Related Sleep Disorder |
| Follow-up: Breathing-Related Sleep Disorder |
| Multimedia: Breathing-Related Sleep Disorder |
| References |
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References
Young T, Evans L, Finn L. Estimation of the clinically diagnosed proportion of sleep apnea syndrome in middle-aged men and women. Sleep. Sep 1997;20(9):705-6. [Medline].
Guilleminault C, Lee JH, Chan A. Pediatric obstructive sleep apnea syndrome. Arch Pediatr Adolesc Med. Aug 2005;159(8):775-85. [Medline].
Kushida CA, Morgenthaler TI, Littner MR, Alessi CA, Bailey D, Coleman J Jr. Practice parameters for the treatment of snoring and Obstructive Sleep Apnea with oral appliances: an update for 2005. Sleep. Feb 1 2006;29(2):240-3. [Medline].
Kushida CA, Littner MR, Hirshkowitz M, Morgenthaler TI, Alessi CA, Bailey D. Practice parameters for the use of continuous and bilevel positive airway pressure devices to treat adult patients with sleep-related breathing disorders. Sleep. Mar 1 2006;29(3):375-80. [Medline].
Caples SM, Gami AS, Somers VK. Obstructive sleep apnea. Ann Intern Med. Feb 1 2005;142(3):187-97. [Medline].
Collop NA. Diagnosing and treating obstructive sleep apnea hypopnea syndrome. J Respir Dis. 2000;21(1):12-20.
Halbower AC, Ishman SL, McGinley BM. Childhood obstructive sleep-disordered breathing: a clinical update and discussion of technological innovations and challenges. Chest. Dec 2007;132(6):2030-41. [Medline].
Shepard JW Jr, Thawley SE. Evaluation of the upper airway by computerized tomography in patients undergoing uvulopalatopharyngoplasty for obstructive sleep apnea. Am Rev Respir Dis. Sep 1989;140(3):711-6. [Medline].
Hudgel DW, Thanakitcharu S. Pharmacologic treatment of sleep-disordered breathing. Am J Respir Crit Care Med. Sep 1998;158(3):691-9. [Medline].
Anstead M, Phillips B. The spectrum of sleep-disordered breathing. Respir Care Clin N Am. Sep 1999;5(3):363-77, viii. [Medline].
Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery: a systematic review and meta-analysis. JAMA. Oct 13 2004;292(14):1724-37. [Medline].
Dhand UK, Dhand R. Sleep disorders in neuromuscular diseases. Curr Opin Pulm Med. Nov 2006;12(6):402-8. [Medline].
Engelman HM, Douglas NJ. Sleep 4: Sleepiness, cognitive functions and quality of life in OSAHS. Thorax. 2004;59(7):618.
Fogel RB, Malhotra A, White DP. Sleep. 2: pathophysiology of obstructive sleep apnoea/hypopnoea syndrome. Thorax. Feb 2004;59(2):159-63. [Medline].
Kakkar RK, Berry RB. Positive airway pressure treatment for obstructive sleep apnea. Chest. Sep 2007;132(3):1057-72. [Medline].
McGinty D, Littner M, Beahm E. Sleep related breathing disorders in older men: a search for underlying mechanisms. Neurobiol Aging. 1982;3(4):337-50. [Medline].
Mickelson SA. Upper airway bypass surgery for obstructive sleep apnea syndrome. Otolaryngol Clin North Am. Dec 1998;31(6):1013-23. [Medline].
Morgenthaler TI, Aurora RN, Brown T, Zak R, Alessi C, Boehlecke B. Practice parameters for the use of autotitrating continuous positive airway pressure devices for titrating pressures and treating adult patients with obstructive sleep apnea syndrome: an update for 2007. An American Academy of Sleep Medicine report. Sleep. Jan 1 2008;31(1):141-7. [Medline].
Morgenthaler TI, Kapen S, Lee-Chiong T, Alessi C, Boehlecke B, Brown T. Practice parameters for the medical therapy of obstructive sleep apnea. Sleep. Aug 1 2006;29(8):1031-5. [Medline].
Oparil S. Arterial hypertension. In: Goldman, Bennett, eds. Cecil Textbook of Medicine. Vol 1. ed. Philadelphia, Pa: WB Saunders; 2000:259-261.
Rappai M, Collop N, Kemp S. The nose and sleep-disordered breathing: what we know and what we do not know. Chest. Dec 2003;124(6):2309-23. [Medline].
Roehrs T, Zorick F, Sicklesteel J. Age-related sleep-wake disorders at a sleep disorder center. J Am Geriatr Soc. Jun 1983;31(6):364-70. [Medline].
Rosen CL. Obstructive sleep apnea syndrome in children: controversies in diagnosis and treatment. Pediatr Clin North Am. Feb 2004;51(1):153-67, vii. [Medline].
Schmidt-Nowara W, Lowe A, Wiegand L. Oral appliances for the treatment of snoring and obstructive sleep apnea: a review. Sleep. Jul 1995;18(6):501-10. [Medline].
Schwab RJ, Goldberg AN. Upper airway assessment: radiographic and other imaging techniques. Otolaryngol Clin North Am. Dec 1998;31(6):931-68. [Medline].
Schwartz AR, Eisele DW, Smith PL. Pharyngeal airway obstruction in obstructive sleep apnea: pathophysiology and clinical implications. Otolaryngol Clin North Am. Dec 1998;31(6):911-8. [Medline].
Sher AE. An overview of sleep disordered breathing for the otolaryngologist. Ear Nose Throat J. Sep 1999;78(9):694-5, 698-700, 703-6 passim. [Medline].
Sher AE, Schechtman KB, Piccirillo JF. The efficacy of surgical modifications of the upper airway in adults with obstructive sleep apnea syndrome. Sleep. Feb 1996;19(2):156-77. [Medline].
Strollo PJ Jr, Sanders MH, Atwood CW. Positive pressure therapy. Clin Chest Med. Mar 1998;19(1):55-68. [Medline].
Suratt PM, McTier RF, Findley LJ. Changes in breathing and the pharynx after weight loss in obstructive sleep apnea. Chest. Oct 1987;92(4):631-7. [Medline].
Young T, Palta M, Dempsey J. The occurrence of sleep-disordered breathing among middle-aged adults. N Engl J Med. Apr 29 1993;328(17):1230-5. [Medline].
Further Reading
Keywords
chronic snoring, habitual snoring, upper airways resistance syndrome, UARS, obstructive sleep apnea, OSA, obesity hypoventilation syndrome, OHS, sleep-related breathing disorder, SRBD, obstructive apnea, central apnea, mixed apnea, hypopnea, nasal continuous positive airway pressure, n-CPAP, tongue-retaining device, TRD, sleep disorder
