JCSM Articles

PSGs: More Than Just the AHI

Long-Term Continuous Positive Airway Pressure Therapy Normalizes High Exhaled Nitric Oxide Levels in Obstructive Sleep Apnea

Study Objectives:

Upper airway inflammation and oxidative stress have been implicated in the pathogenesis of obstructive sleep apnea (OSA) and may be linked to cardiovascular consequences. We prospectively examined fraction of exhaled nitric oxide (FENO), a surrogate marker of upper airway inflammation using a portable nitric oxide analyzer (NIOX MINO).

Design:

In consecutive adult nonsmokers with suspected OSA, FENO was measured immediately before and after polysomnographic studies, and within 1-3 months following continuous positive airway pressure (CPAP) therapy.

Measurement and Results:

FENO levels were increased in the 75 patients with OSA compared to the 29 controls, both before sleep (13.4 ± 6.5 ppb vs. 6.5 ± 3.5; p < 0.001) and after sleep (19.0 ± 7.7 ppb vs. 6.9 ± 3.7; p < 0.001). Furthermore, in patients with OSA, FENO levels were significantly higher post-sleep than pre-sleep (19.0 ± 7.7 ppb vs. 13.4 ± 6.5; p < 0.001), while there was no significant overnight change in patients without OSA. The rise in FENO correlated with the apnea-hypopnea index (r = 0.65, p < 0.001), nadir oxygen saturation (r = 0.54, p < 0.001), and arousal index (r = 0.52, p < 0.001). Thirty-seven of these patients underwent CPAP titration and treatment. Successful titration was associated with a lower overnight increase in FENO (7.2 ± 3.3 vs. 11.0 ± 4.3, p = 0.02). FENO levels declined after 1-3 months of CPAP therapy (11.7 ± 4.4 ppb, p < 0.001).

Conclusions:

FENO levels are elevated in OSA, correlate with severity, and decrease after positive pressure therapy. This study supports the role of upper airway inflammation in OSA pathogenesis and a possible role for FENO in monitoring CPAP therapy.

Citation:

Chua AP; Aboussouan LS; Minai OA; Paschke K; Laskowski D; Dweik RA. Long-term continuous positive airway pressure therapy normalizes high exhaled nitric oxide levels in obstructive sleep apnea. J Clin Sleep Med 2013;9(6):529-535.

Impact of Group Education on Continuous Positive Airway Pressure Adherence

Study Objectives:

To compare the impact of a group educational program versus individual education on continuous positive airway pressure (CPAP) adherence.

Methods:

Post hoc assessment of a performance improvement initiative designed to improve clinic efficiency, access to care, and time to initiate therapy. Consecutive patients newly diagnosed with obstructive sleep apnea (OSA) initiating CPAP therapy participated in either an individual or group educational program. The content and information was similar in both strategies.

Results:

Of 2,116 included patients, 1,032 received education regarding OSA and CPAP through a group clinic, and 1,084 received individual education. Among the cohort, 76.6% were men, mean age 48.3 ± 9.2 years, mean body mass index 29.6 ± 4.6 kg/m², and mean apnea-hypopnea index was 33.3 ± 24.4 events/hour. Baseline characteristics were similar between groups. CPAP adherence was significantly greater in those participating in a group program than those receiving individual education. Specifically, CPAP was used for more nights (67.2% vs. 62.1%, p = 0.02) and more hours per night during nights used (4.3 ± 2.1 vs. 3.7 ± 2.8, p = 0.03). Further, fewer individuals discontinued therapy (10.6% vs. 14.5%, p < 0.001), more achieved regular use of CPAP (45.2%. vs. 40.6%, p = 0.08), and time to initiate therapy was shorter (13.2 ± 3.1 versus 24.6 ± 7.4 days, p < 0.001). Group education resulted in a 3- to 4-fold increase in the number of patients seen per unit time.

Conclusions:

A group educational program facilitated improved CPAP adherence. If confirmed by prospective randomized studies, group CPAP education may be an appropriate alternative to individual counseling, may improve acceptance of and adherence to therapy, and decrease time to treatment.

Commentary:

A commentary on this article appears in this issue on page

551.

Citation:

Lettieri CJ; Walter RJ. Impact of group education on continuous positive airway pressure adherence. J Clin Sleep Med 2013;9(6):537-541.

A Pilot Study of CPAP Adherence Promotion by Peer Buddies with Sleep Apnea

Study Objectives:

To evaluate patient ratings of the acceptability of a peer buddy system (PBS). To promote continuous positive airway pressure (CPAP) therapy adherence in patients with obstructive sleep apnea (OSA). To obtain preliminary data on the effectiveness of PBS on sleep-specific health-related quality of life and CPAP adherence.

Design:

Prospective, randomized, and controlled study.

Setting:

Academic Center.

Participants:

Thirty-nine patients with OSA and 13 patients with OSA who were experienced CPAP users.

Interventions:

Recently diagnosed patients with OSA were randomly assigned to either the PBS to promote CPAP adherence (intervention group) or usual care (control group).

Measurements:

Patient satisfaction, Functional Outcomes of Sleep Questionnaire (FOSQ), CPAP adherence, vigilance, self-efficacy, and patient activation were measured.

Results:

Ninety-one percent of the subjects rated the PBS as very satisfactory (68%) or satisfactory (23%). During the 90 days of therapy, weekly CPAP adherence was greater in the intervention than the usual care group (MANOVA; F = 2.29; p = 0.04). Patient satisfaction was positively correlated with CPAP adherence (R² = 0.14; p = 0.02). We did not find any group differences for FOSQ, vigilance, self-efficacy, or patient activation in this pilot study.

Conclusion:

Our pilot study suggests that the PBS intervention is feasible and received high patient satisfaction ratings. CPAP adherence may be improved by peer-driven intervention, but a larger, adequately powered study is needed.

Clinical Trial Information:

ClinicalTrials.gov identifier: NCT01164683.

Commentary:

A commentary on this article appears in this issue on page

551.

Citation:

Parthasarathy S; Wendel C; Haynes PL; Atwood C; Kuna S. A pilot study of CPAP adherence promotion by peer buddies with sleep apnea. J Clin Sleep Med 2013;9(6):543-550.

Don't Start Celebrating—CPAP Adherence Remains a Problem

Comparison of Polysomnographic and Clinical Presentations and Predictors for Cardiovascular-Related Diseases between Non-Obese and Obese Obstructive Sleep Apnea among Asians

Introduction:

Unlike Caucasians, many Asians with obstructive sleep apnea (OSA) are non-obese but are affected by the disease due to predisposing craniofacial structure. Therefore, non-obese and obese OSA may represent different disease entities. The associated risk factors for developing cardiovascular-related diseases, consequently, may be considered separately for the two types of OSA.

Method:

We reviewed polysomnographic studies performed in adults (aged ≥ 18 years) diagnosed with OSA (respiratory disturbance index [RDI] ≥ 5). We divided the patients into obese (body mass index [BMI] ≥ 25) and non-obese (BMI < 25) groups. We aimed to determine the differences between these two groups in terms of clinical presentations, polysomno-graphic findings, and association with cardiovascular-related diseases including hypertension, diabetes mellitus, coronary artery disease, and/or cerebrovascular disease.

Results:

Among 194 patients with OSA (RDI ≥ 5), 63.4% were non-obese and 36.6% were obese. Compared with obese OSA patients, non-obese OSA patients were noted to have smaller neck size, less prevalence of hypertension, and less history of frequent nocturia (> 3-4/week), with equal prevalence of excessive daytime sleepiness. Overall, non-obese OSA patients were noted to have milder disease indicated by lower total, supine, and non-supine, NREM RDI and higher mean and nadir oxygen saturations. In the non-obese group, only total obstructive apnea index (OAI) was noted to be a predictor for developing any of the cardiovascular-related diseases after controlling for age, sex, and RDI (odds ratio = 9.7). However, in the obese OSA group, frequent snoring (> 50% of total sleep time), low sleep efficiency (≤ 90%), and low mean oxygen saturation (< 95%) were noted to be significant predictors of cardiovascular-related diseases (odds ratios = 12.3, 4.2, and 5.2, respectively).

Conclusion:

Among Asians, most OSA patients were not obese. Compared to obese OSA patients, non-obese OSA patients were noted to have less prevalence of hypertension and less history of nocturia. They were also noted to have overall milder OSA. Only OAI was noted to be a significant predictor for cardiovascular-related disease in the non-obese OSA group.

Citation:

Chirakalwasan N; Teerapraipruk B; Simon R; Hirunwiwatkul P; Jaimchariyatam N; Desudchit T; Charakorn N; Wanlapakorn C. Comparison of polysomnographic and clinical presentations and predictors for cardiovascular-related diseases between non-obese and obese obstructive sleep apnea among Asians. J Clin Sleep Med 2013;9(6):553-557.

Sleep Habits, Insomnia, and Daytime Sleepiness in a Large and Healthy Community-Based Sample of New Zealanders

Study Objectives:

To determine the relationship between sleep complaints, primary insomnia, excessive daytime sleepiness, and lifestyle factors in a large community-based sample.

Design:

Cross-sectional study.

Setting:

Blood donor sites in New Zealand.

Patients or Participants:

22,389 individuals aged 16-84 years volunteering to donate blood.

Interventions:

N/A.

Measurements:

A comprehensive self-administered questionnaire including personal demographics and validated questions assessing sleep disorders (snoring, apnea), sleep complaints (sleep quantity, sleep dissatisfaction), insomnia symptoms, excessive daytime sleepiness, mood, and lifestyle factors such as work patterns, smoking, alcohol, and illicit substance use. Additionally, direct measurements of height and weight were obtained.

Results:

One in three participants report < 7-8 h sleep, 5 or more nights per week, and 60% would like more sleep. Almost half the participants (45%) report suffering the symptoms of insomnia at least once per week, with one in 5 meeting more stringent criteria for primary insomnia. Excessive daytime sleepiness (evident in 9% of this large, predominantly healthy sample) was associated with insomnia (odds ratio [OR] 1.75, 95% confidence interval [CI] 1.50 to 2.05), depression (OR 2.01, CI 1.74 to 2.32), and sleep disordered breathing (OR 1.92, CI 1.59 to 2.32). Long work hours, alcohol dependence, and rotating work shifts also increase the risk of daytime sleepiness.

Conclusions:

Even in this relatively young, healthy, non-clinical sample, sleep complaints and primary insomnia with subsequent excess daytime sleepiness were common. There were clear associations between many personal and lifestyle factors—such as depression, long work hours, alcohol dependence, and rotating shift work—and sleep problems or excessive daytime sleepiness.

Citation:

Wilsmore BR; Grunstein RR; Fransen M; Woodward M; Norton R; Ameratunga S. Sleep habits, insomnia, and daytime sleepiness in a large and healthy community-based sample of New Zealanders. J Clin Sleep Med 2013;9(6):559-566.

The Relation between Insomnia Symptoms, Mood, and Rumination about Insomnia Symptoms

Study Objectives:

Research suggests that rumination may play an important role in insomnia. Whereas some have suggested that rumination mainly relates to depression, the evidence suggests that there may be insomnia-specific rumination. This paper explores insomnia symptom rumination across two distinct samples of varying levels of depressed mood and insomnia symptom severity.

Methods:

The first sample consisted of nonclinical participants (N = 327) with a range of insomnia and depressed mood symptoms, and the second sample consisted of those who met both Major Depressive Disorder and Insomnia diagnoses (N = 66). Rather than relying on a measure developed for those with depression, we developed and tested an insomnia-specific measurement scale based on items from previous rumination studies and the addition of items derived from common daytime insomnia symptoms.

Results:

Internal consistency was highly acceptable across the two samples for the new insomnia-specific rumination measure (Cronbach α was 0.93 and 0.94). In the first study, poor sleepers reported significantly higher levels of daytime symptom rumination than did good sleepers. Across both studies, rumination about daytime insomnia symptoms and depression were signifi-cantly correlated; however, insomnia rumination scores predicted insomnia even after controlling for depression. Moreover, in Study 2, insomnia-specific rumination was related to insomnia, but general depressive rumination was not predictive of insomnia.

Conclusions:

The findings provide support for the use of this insomnia-specific rumination scale; moreover the findings support previous observances regarding rumination about daytime insomnia symptoms that are not exclusive to depression.

Citation:

Carney CE; Harris AL; Falco A; Edinger JD. The relation between insomnia symptoms, mood, and rumination about insomnia symptoms. J Clin Sleep Med 2013;9(6):567-575.

Perceived Insufficient Rest or Sleep among Veterans: Behavioral Risk Factor Surveillance System 2009

Study Objectives:

Sleep problems are of particular concern among the active duty military population as factors such as inconsistent work hours and deployment may compromise adequate sleep and adversely impact performance. However, few prior studies have investigated whether the prevalence of sleep problems differ between Veterans and demographically similar non-Veterans. The purpose of this study is to investigate whether self-reported insufficient rest or sleep varies in relation to Veteran status and to identify high-risk groups of Veterans.

Methods:

This study used data from the 2009 Behavioral Risk Factor Surveillance System (analyzed in 2011), a state based national telephone survey of non-institutionalized US adults. Insufficient rest was assessed in 411,313 adults aged 21 and older, of whom 55,361 were Veterans. Sleep duration was assessed in 6 states (n = 4,936 Veterans and 30,983 non-Veterans). Model-based direct rate adjustment was used to estimate the prevalence of insufficient rest or sleep while controlling for confounding. Multivariable logistic regression was used to estimate odds ratios of insufficient sleep or rest in subgroups of Veterans.

Results:

After multivariable adjustment, insufficient rest or sleep (22.7% vs. 21.1%, p < 0.001) and short sleep duration (< 7 h/night, 34.9% vs. 31.3%, p = 0.026) were more common among Veterans than non-Veterans. When the Veteran group was further divided among newly transitioned (≤ 12 months) and longer-term Veterans (> 12 months), the overall test for a difference was not statistically significant between groups, mainly because there was little difference in sleep between the two groups of Veterans. High-risk Veteran subgroups included those who were 21-44 years of age (vs. 65-74), women, non-whites, current smokers, obese, unable to work, and those in poor health.

Conclusions:

This study suggests that Veterans have a high burden of sleep problems and identifies subgroups that should be targeted to receive interventions and enhanced education regarding insufficient sleep.

Citation:

Faestel PM; Littell CT; Vitiello MV; Forsberg CW; Littman AJ. Perceived insufficient rest or sleep among Veterans: Behavioral Risk Factor Surveillance System 2009. J Clin Sleep Med 2013;9(6):577-584.

Total Sleep Time and Other Sleep Characteristics Measured by Actigraphy Do Not Predict Incident Hypertension in a Cohort of Community-Dwelling Older Men

Study Objective:

To evaluate whether actigraphy-measured total sleep time and other sleep characteristics predict incident hypertension in older men.

Methods:

Study subjects were community-dwelling participants in the ancillary sleep study of the Osteoporotic Fractures in Men Study (MrOS) who were normotensive at the time of actigraphy (based on self-report, lack of antihypertensive medication use, and with systolic blood pressure < 140 mm Hg and diastolic blood pressure < 90 mm Hg). In 853 community-dwelling men 67 years and older (mean 75.1 years), sleep measures (total sleep time [TST]), percent sleep [%-sleep], latency, and wake after sleep onset [WASO]) were obtained using validated wrist actigraphy with data collected over a mean duration of 5.2 consecutive 24-h periods. We evaluated incident hypertension (based on self-report, use of antihypertensive medication, or measured systolic blood pressure ≥ 140 mm Hg or diastolic blood pressure ≥ 90 mm Hg) at a follow-up visit an average of 3.4 years later. Baseline prehypertension was defined as a systolic blood pressure 120 to < 140 mm Hg or diastolic blood pressure 80 to < 90 mm Hg.

Results:

At follow-up, 31% of initially normotensive men were hypertensive (264 of 853). Those with incident hypertension had higher baseline body mass index (BMI; kg/m²) and were more likely to have had prehypertension at the sleep visit than those men who remained normotensive. However, neither TST (reference 6 to < 8 h; < 6 h OR 0.96 [95% CI 0.7, 1.3] and ≥ 8 h OR 0.93 [0.5, 1.7]) nor the other actigraphic-measured sleep variables, including % -sleep (reference > 85%; < 70% OR 1.17 [0.66, 2.08]) and 70% to ≤ 85% OR 1.23 (0.9, 1.68), sleep latency (reference < 30 min; ≥ 30 min OR 1.29 [0.94, 1.76]), or WASO (reference < 30 min; 30 to < 60 min OR 0.7 [0.43, 1.14] and ≥ 60 min OR 0.92 [0.58, 1.47]) differed in those community-dwelling men who developed incident hypertension compared to those who remained normotensive.

Conclusion:

TST and other sleep parameters determined by wrist actigraphy were not associated with incident hypertension in community-dwelling older men.

Citation:

Fung MM; Peters K; Ancoli-Israel S; Redline S; Stone KL; Barrett-Connor E. Total sleep time and other sleep characteristics measured by actigraphy do not predict incident hypertension in a cohort of community-dwelling older men. J Clin Sleep Med 2013;9(6):585-591.

Sleep Oxygen Desaturation Predicts Survival in Idiopathic Pulmonary Fibrosis

Background:

Recent studies suggest poor sleep quality in patients with idiopathic pulmonary fibrosis (IPF). However, so far, the impact of IPF-related sleep breathing disorders (SBDs) on survival has not been extensively studied.

Methods:

In a cohort of 31 (24 males) treatment-naïve, newly diagnosed consecutive IPF patients, we prospectively investigated the relationship of SBD parameters such as apnea-hypopnea index (AHI), maximal difference in oxygen saturation between wakefulness and sleep (maxdiff SpO₂), and lowest sleep oxygen saturation (lowest SpO₂) with clinical (survival, dyspnea, daytime sleepiness), pulmonary function, submaximal (6-min walk test [6MWT]) and maximal exercise variables (cardiopulmonary exercise test [CPET]), and right ventricular systolic pressure (RVSP).

Results:

Sleep oxygen desaturation exceeded significantly that of maximal exercise (p < 0.001). Maxdiff SpO₂ was inversely related to survival, DLCO%, and SpO₂ after 6MWT, and directly with dyspnea, AHI, and RVSP. The lowest SpO₂ was directly related to survival and to functional (TLC%, DLCO%) as well as submaximal and maximal exercise variables (6MWT distance, SpO₂ after 6MWT, peak oxygen consumption/kg, SpO₂ at peak exercise), while an inverse association with dyspnea score, AHI, and RVSP was observed.

Conclusions:

Our findings provide evidence that intermittent sleep oxygen desaturation significantly exceeds that of maximal exercise and is associated with survival in IPF patients. Furthermore, they imply the existence of a link between lung damage and apnea events resulting to the induction and severity of intermittent sleep oxygen desaturation that aggravate pulmonary arterial hypertension and influence IPF survival.

Commentary:

A commentary on this article appears in this issue on page

603.

Citation:

Kolilekas L; Manali E; Vlami KA; Lyberopoulos P; Triantafillidou C; Kagouridis K; Baou K; Gyftopoulos S; Vougas KN; Karakatsani A; Alchanatis M; Papiris S. Sleep oxygen desaturation predicts survival in idiopathic pulmonary fibrosis. J Clin Sleep Med 2013;9(6):593-601.

Can We Predict the Survival of Idiopathic Pulmonary Fibrosis Patients? Sleep Must Be Re-appreciated

Sleep Duration and Reported Functional Capacity among Black and White US Adults

Objective:

Evidence suggests that individuals reporting sleeping below or above the population's modal sleep duration are at risk for diabetes, hypertension, and other cardiovascular diseases. Evidence also indicates that individuals with these conditions have reduced functional capacity. We assessed whether reported sleep duration and functional capacity are independently associated and whether individuals' race/ethnicity has an effect on this association.

Method:

Data were obtained from 29,818 black and white Americans (age range: 18-85 years) who participated in the 2005 National Health Interview Survey (NHIS). The NHIS uses a multistage area probability design sampling of non-institutionalized representatives of the US civilian population. Of the sample, 85% were white and 56% were women.

Results:

Univariate logistic regression analysis showed that individuals sleeping < 6 h were 3.55 times more likely than those sleeping 6-8 h to be functionally impaired (34% vs 13%; p < 0.001). Likewise, those sleeping > 8 h were 3.77 times more likely to be functionally impaired (36% vs 13%; p < 0.001). Individuals of the black race/ethnicity were more likely to be functionally impaired than their white counterparts (23% vs 19%; p < 0.001). Multivariate-adjusted regression analyses showed significant interactions between individuals' race/ethnicity and short sleep with respect to functional capacity (black: OR = 2.78, p < 0.0001; white: OR = 2.30, p < 0.0001). Signifi-cant interactions between race/ethnicity and long sleep were also observed (black: OR = 2.43, p < 0.001; white: OR = 2.63, p < 0.001).

Conclusion:

Our findings suggest that individuals' habitual sleep duration and their race/ethnicity are significant predictors of their functional capacity.

Citation:

Brimah P; Oulds F; Olafiranye O; Ceide M; Dillon S; Awoniyi O; Nunes J; Jean-Louis G. Sleep duration and reported functional capacity among black and white US adults. J Clin Sleep Med 2013;9(6):605-609.

Narcolepsy with Cataplexy Mimicry: The Strange Case of Two Sisters

We report on two sisters, 17 and 12 years of age, with clinical features suggesting narcolepsy with cataplexy (NC): daytime sleepiness, spontaneous and emotionally triggered sudden falls to the ground, and overweight/obesity. MSLT showed borderline sleep latency, with 1 and 0 sleep onset REM periods. HLA typing disclosed the DQB1*0602 allele. Video-polygraphy of the spells ruled out NC diagnosis by demonstrating their easy elicitation by suggestion, with wake EEG, electromyo-graphic persistence of muscle tone, and stable presence of tendon reflexes (i.e., pseudo-cataplexy), together with normal cerebrospinal hypocretin-1 levels.

Our cases emphasize the need of a clear depiction of cataplexy pattern at the different ages, the usefulness of examining ictal neurophysiology, and collecting all available disease markers in ambiguous cases.

Citation:

Pizza F; Vandi S; Poli F; Moghadam KK; Fran-ceschini C; Bellucci C; Cipolli C; Ingravallo F; Natalini G; Mignot E; Plazzi G. Narcolepsy with cataplexy mimicry: the strange case of two sisters. J Clin Sleep Med 2013;9(6):611-612.

Obstructive Sleep Apnea and Nonarteritic Anterior Ischemic Optic Neuropathy: Evidence for an Association

Nonarteritic anterior ischemic optic neuropathy (NAION) is the most prevalent optic nerve disorder among patients over 50 years of age, characterized by sudden onset, painless visual loss, with an accompanying relative afferent pupillary defect and optic disc edema. Although the pathophysiology of NAION has not been fully elucidated, several risk factors have been considered, including advanced age, systemic hypertension, diabetes mellitus, and certain optic disc morphologies. An association between obstructive sleep apnea (OSA) and NAION has also been recognized. One prospective cohort study indicated that the relative risk of OSA among patients with NAION was 4.9; a later retrospective cohort study demonstrated that patients with OSA not treated with continuous positive airway pressure (CPAP) had a 16% increased hazard of developing NAION compared to patients without OSA.The following review will discuss the most recent understanding of the relationship between OSA and NAION, with implications for further research and prevention strategies.

Citation:

Archer EL; Pepin S. Obstructive sleep apnea and nonarteritic anterior ischemic optic neuropathy: evidence for an association. J Clin Sleep Med 2013;9(6):613-618.

JCSM Articles

PSGs: More Than Just the AHI

Long-Term Continuous Positive Airway Pressure Therapy Normalizes High Exhaled Nitric Oxide Levels in Obstructive Sleep Apnea

Study Objectives:

Design:

Measurement and Results:

Conclusions:

Citation:

Impact of Group Education on Continuous Positive Airway Pressure Adherence

Study Objectives:

Methods:

Results:

Conclusions:

Commentary:

Related Article

Citation:

A Pilot Study of CPAP Adherence Promotion by Peer Buddies with Sleep Apnea

Study Objectives:

Design:

Setting:

Participants:

Interventions:

Measurements:

Results:

Conclusion:

Clinical Trial Information:

Commentary:

Related Article

Citation:

Don't Start Celebrating—CPAP Adherence Remains a Problem

Comparison of Polysomnographic and Clinical Presentations and Predictors for Cardiovascular-Related Diseases between Non-Obese and Obese Obstructive Sleep Apnea among Asians

Introduction:

Method:

Results:

Conclusion:

Citation:

Sleep Habits, Insomnia, and Daytime Sleepiness in a Large and Healthy Community-Based Sample of New Zealanders

Study Objectives:

Design:

Setting:

Patients or Participants:

Interventions:

Measurements:

Results:

Conclusions:

Citation:

The Relation between Insomnia Symptoms, Mood, and Rumination about Insomnia Symptoms

Study Objectives:

Methods:

Results:

Conclusions:

Citation:

Perceived Insufficient Rest or Sleep among Veterans: Behavioral Risk Factor Surveillance System 2009

Study Objectives:

Methods:

Results:

Conclusions:

Citation:

Total Sleep Time and Other Sleep Characteristics Measured by Actigraphy Do Not Predict Incident Hypertension in a Cohort of Community-Dwelling Older Men

Study Objective:

Methods:

Results:

Conclusion:

Citation:

Sleep Oxygen Desaturation Predicts Survival in Idiopathic Pulmonary Fibrosis

Background:

Methods:

Results:

Conclusions:

Commentary:

Related Article

Citation:

Can We Predict the Survival of Idiopathic Pulmonary Fibrosis Patients? Sleep Must Be Re-appreciated

Sleep Duration and Reported Functional Capacity among Black and White US Adults

Objective:

Method:

Results:

Conclusion:

Citation:

Narcolepsy with Cataplexy Mimicry: The Strange Case of Two Sisters