Faculty Bibliography

BACKGROUND: Obstructive sleep apnea (OSA) is commonly found in individuals with traumatic brain injury (TBI) and may exacerbate TBI-related symptoms. Nocturnal polysomnography (NPSG) is considered the gold standard for detecting the presence of sleep apnea. However, there is a limitation with its use known as the "first-night effect" (aberrant polysomnography findings on the first night in a sleep lab). OBJECTIVE: The primary objectives were to investigate the night-to-night consistency of diagnosing and classifying obstructive sleep apnea in individuals with TBI, and ascertain if individuals with TBI are prone to a first-night effect. METHODS: 47 community-dwelling adults with self-reported mild-to-severe TBI underwent two nights of in-laboratory NPSG to examine variability between the first and second night with regards to OSA diagnosis and severity as well as sleep architecture. RESULTS: OSA detection and severity were consistent from night-to-night in 89% of participants with TBI. Participants with TBI demonstrated longer REM latency on the first night compared to the second night of sleep study. CONCLUSIONS: These findings indicate that two nights of in-laboratory NPSG are generally consistent in reliably diagnosing OSA in individuals with TBI and that first-night effects are minimal. One night of NPSG has diagnostic utility in the evaluation of sleep disorders in individuals with TBI.

Obstructive sleep apnoea and type 2 diabetes are common medical disorders that have important clinical, epidemiological, and public health implications. Research done in the past two decades indicates that obstructive sleep apnoea, through the effects of intermittent hypoxaemia and sleep fragmentation, could contribute independently to the development of insulin resistance, glucose intolerance, and type 2 diabetes. Conversely, type 2 diabetes might increase predisposition to, or accelerate progression of, obstructive and central sleep apnoea, possibly through the development of peripheral neuropathy and abnormalities of ventilatory and upper airway neural control. Although more research is needed to clarify the mechanisms underlying the bidirectional association between the two disorders, their frequent coexistence should prompt all health-care professionals to embrace clinical practices that include screening of a patient presenting with one disorder for the other. Early identification of obstructive sleep apnoea in patients with metabolic dysfunction, including type 2 diabetes, and assessment for metabolic abnormalities in those with obstructive sleep apnoea could reduce cardiovascular disease risk and improve the quality of life of patients with these chronic diseases.

BACKGROUND:Although a level 1 nocturnal polysomnogram (PSG) is often used to evaluate children with non-respiratory sleep disorders, there are no published evidence-based practice parameters focused on the pediatric age group. In this report, we present practice parameters for the indications of polysomnography and the multiple sleep latency test (MSLT) in the assessment of non-respiratory sleep disorders in children. These practice parameters were reviewed and approved by the Board of Directors of the American Academy of Sleep Medicine (AASM). METHODS:A task force of content experts was appointed by the AASM to review the literature and grade the evidence according to the American Academy of Neurology grading system. RECOMMENDATIONS FOR PSG AND MSLT USE/UNASSIGNED:PSG is indicated for children suspected of having periodic limb movement disorder (PLMD) for diagnosing PLMD. (STANDARD)The MSLT, preceded by nocturnal PSG, is indicated in children as part of the evaluation for suspected narcolepsy. (STANDARD)Children with frequent NREM parasomnias, epilepsy, or nocturnal enuresis should be clinically screened for the presence of comorbid sleep disorders and polysomnography should be performed if there is a suspicion for sleep-disordered breathing or periodic limb movement disorder. (GUIDELINE)The MSLT, preceded by nocturnal PSG, is indicated in children suspected of having hypersomnia from causes other than narcolepsy to assess excessive sleepiness and to aid in differentiation from narcolepsy. (OPTION)The polysomnogram using an expanded EEG montage is indicated in children to confirm the diagnosis of an atypical or potentially injurious parasomnia or differentiate a parasomnia from sleep-related epilepsy (OPTION)Polysomnography is indicated in children suspected of having restless legs syndrome (RLS) who require supportive data for diagnosing RLS. (OPTION) RECOMMENDATIONS AGAINST PSG USE: Polysomnography is not routinely indicated for evaluation of children with sleep-related bruxism. (STANDARD) CONCLUSIONS: The nocturnal polysomnogram and MSLT are useful clinical tools for evaluating pediatric non-respiratory sleep disorders when integrated with the clinical evaluation.

BACKGROUND:Sleepiness is one of the most burdensome symptoms of sleep-disordered breathing (SDB). While caffeine is frequently used to avert sleepiness, the association between SDB and caffeine use has not been thoroughly explored. The current study examined whether SDB is associated with caffeine consumption and if factors such as sex, age, and daytime sleepiness explain or modify the association. METHODS:Data from the Sleep Heart Health Study, a community-based study on the consequences of SDB, were used to characterize the association between SDB and caffeine intake. SDB was assessed with full-montage polysomnography. Caffeine use was quantified as the number of cans of soda or the cups of coffee or tea consumed daily. The Epworth Sleepiness Scale was used to assess daytime sleepiness. Multivariable negative binomial regression models were used to characterize the independent association between SDB and caffeine use. RESULTS:Caffeinated soda, but not tea or coffee, intake was independently associated with SDB severity. Compared with participants without SDB, the relative ratios for caffeinated soda consumption in women with mild, moderate, and severe SDB were 1.20 (CI, 1.03-1.41), 1.46 (CI, 1.14-1.87), and 1.73 (CI, 1.23-2.42), respectively. For men, an association was only noted with severe SDB and caffeinated soda use. Age did not modify the SDB-caffeine association, and sleepiness could not explain the observed associations. CONCLUSIONS:SDB is independently associated with caffeinated soda use in the general community. Identifying excessive caffeine used in SDB has potential significance given the cardiovascular effects of caffeine and untreated SDB.

A systematic literature review and meta-analyses (where appropriate) were performed to update the previous AASM practice parameters on the treatments, both dopaminergic and other, of RLS and PLMD. A considerable amount of literature has been published since these previous reviews were performed, necessitating an update of the corresponding practice parameters. Therapies with a STANDARD level of recommendation include pramipexole and ropinirole. Therapies with a GUIDELINE level of recommendation include levodopa with dopa decarboxylase inhibitor, opioids, gabapentin enacarbil, and cabergoline (which has additional caveats for use). Therapies with an OPTION level of recommendation include carbamazepine, gabapentin, pregabalin, clonidine, and for patients with low ferritin levels, iron supplementation. The committee recommends a STANDARD AGAINST the use of pergolide because of the risks of heart valve damage. Therapies for RLS secondary to ESRD, neuropathy, and superficial venous insufficiency are discussed. Lastly, therapies for PLMD are reviewed. However, it should be mentioned that because PLMD therapy typically mimics RLS therapy, the primary focus of this review is therapy for idiopathic RLS.

The International Classification of Sleep Disorders, Second Edition (ICSD-2) distinguishes 5 subtypes of central sleep apnea syndromes (CSAS) in adults. Review of the literature suggests that there are two basic mechanisms that trigger central respiratory events: (1) post-hyperventilation central apnea, which may be triggered by a variety of clinical conditions, and (2) central apnea secondary to hypoventilation, which has been described with opioid use. The preponderance of evidence on the treatment of CSAS supports the use of continuous positive airway pressure (CPAP). Much of the evidence comes from investigations on CSAS related to congestive heart failure (CHF), but other subtypes of CSAS appear to respond to CPAP as well. Limited evidence is available to support alternative therapies in CSAS subtypes. The recommendations for treatment of CSAS are summarized as follows: CPAP therapy targeted to normalize the apnea-hypopnea index (AHI) is indicated for the initial treatment of CSAS related to CHF. (STANDARD)Nocturnal oxygen therapy is indicated for the treatment of CSAS related to CHF. (STANDARD)Adaptive Servo-Ventilation (ASV) targeted to normalize the apnea-hypopnea index (AHI) is indicated for the treatment of CSAS related to CHF. (STANDARD)BPAP therapy in a spontaneous timed (ST) mode targeted to normalize the apnea-hypopnea index (AHI) may be considered for the treatment of CSAS related to CHF only if there is no response to adequate trials of CPAP, ASV, and oxygen therapies. (OPTION)The following therapies have limited supporting evidence but may be considered for the treatment of CSAS related to CHF after optimization of standard medical therapy, if PAP therapy is not tolerated, and if accompanied by close clinical follow-up: acetazolamide and theophylline. (OPTION)Positive airway pressure therapy may be considered for the treatment of primary CSAS. (OPTION)Acetazolamide has limited supporting evidence but may be considered for the treatment of primary CSAS. (OPTION)The use of zolpidem and triazolam may be considered for the treatment of primary CSAS only if the patient does not have underlying risk factors for respiratory depression. (OPTION)The following possible treatment options for CSAS related to end-stage renal disease may be considered: CPAP, supplemental oxygen, bicarbonate buffer use during dialysis, and nocturnal dialysis. (OPTION) .

An increased risk for obstructive sleep apnea (OSA) has been suggested for World Trade Center (WTC)-exposed workers. The authors reviewed the results from nocturnal polysomnograms (PSGs), to investigate diagnostic differences between WTC-exposed and -unexposed subjects. Six hundred fifty-six nocturnal PSGs performed at our sleep center were reviewed, 272 of them in former WTC workers. Seven diagnostic categories were compared between the 2 groups by bivariate and logistic regression analyses. The WTC group had a significantly higher predominance of the male gender, but slightly lower body mass index (BMI). There was no significant difference in the distribution of PSG diagnoses between the 2 groups in unadjusted (p = .56) or adjusted (p = .49) analyses. The authors did not identify a significant difference in PSG diagnoses between the WTC-exposed and -unexposed subjects. OSA was significantly associated with age, BMI, and gender in this patient population.