Habitual sleep and kidney function in chronic kidney disease: the Chronic Renal Insufficiency Cohort study.

Physiological evidence suggests that sleep modulates kidney function. Our objective was to examine the cross-sectional association between kidney function and objectively-estimated habitual sleep duration, quality and timing in a cohort of patients with mild to moderate chronic kidney disease. This study involved two US clinical centers of the Chronic Renal Insufficiency Cohort (CRIC) study, including 432 participants in a CRIC ancillary sleep study. Habitual sleep duration, quality and timing were measured using wrist actigraphy for 5-7 days. Validated sleep questionnaires assessed subjective sleep quality, daytime sleepiness and risk of sleep apnea. Kidney function was assessed with the estimated glomerular filtration rate using the Chronic Kidney Disease Epidemiology Collaboration equation, and the urinary protein to creatinine ratio. Lower estimated glomerular filtration rate was associated with shorter sleep duration (-1.1 mL min-1  1.73 m-2 per hour less sleep, P = 0.03), greater sleep fragmentation (-2.6 mL min-1  1.73 m-2 per 10% higher fragmentation, P < 0.001) and later timing of sleep (-0.9 mL min-1  1.73 m-2 per hour later, P = 0.05). Higher protein to creatinine ratio was also associated with greater sleep fragmentation (approximately 28% higher per 10% higher fragmentation, P < 0.001). Subjective sleep quality, sleepiness and persistent snoring were not associated with estimated glomerular filtration rate or protein to creatinine ratio. Thus, worse objective sleep quality was associated with lower estimated glomerular filtration rate and higher protein to creatinine ratio. Shorter sleep duration and later sleep timing were also associated with lower estimated glomerular filtration rate. Physicians treating patients with chronic kidney disease should consider inquiring about sleep and possibly sending for clinical sleep assessment. Longitudinal and interventional trials are needed to understand causal direction.

Risk of obstructive sleep apnea in African American patients with chronic rhinosinusitis.

BACKGROUND: It is widely known that patients with chronic rhinosinusitis (CRS) commonly experience sleep disruption. Many of these patients have the associated diagnosis of obstructive sleep apnea (OSA). However, little is known about the risk factors for developing OSA in the CRS population. OBJECTIVE: To identify the risk factors for OSA in CRS to determine who should be screened for OSA among patients with CRS. METHODS: We evaluated a large cohort of patients with confirmed diagnostic criteria for CRS. Patient medical records were reviewed to identify those with OSA confirmed by overnight polysomnography. Records were further reviewed for demographic information (age, sex, race, and ethnicity), body mass index, and medical history, including the presence of nasal polyps, asthma, aspirin-exacerbated respiratory disease, allergic rhinitis, and eczema. The number of endoscopic sinus operations, duration of CRS, presence of subjective smell loss, and computed tomography Lund-Mackay score were also ascertained. RESULTS: A total of 916 patients with CRS were included in the study. Implementation of a multivariable regression model for identifying adjusted risk factors revealed that African American patients had a significantly higher risk for OSA than white patients, with an adjusted odds ratio of 1.98 (95% confidence interval, 1.19-3.29). Furthermore, patients with CRS without nasal polyps were at higher risk for OSA, with an odds ratio of 1.63 (95% confidence interval, 1.02-2.61) compared with patients with CRS with nasal polyps. CONCLUSION: African American patients with CRS were at higher risk for OSA compared with white patients, and this patient group needs to be screened for OSA.

The impact of neck circumference on hypoglossal nerve stimulator therapy outcomes.

STUDY OBJECTIVES: Hypoglossal nerve stimulation (HGNS) therapy has historically had strict eligibility requirements including a body mass index (BMI) < 32 kg/m2. However, recent Food and Drug Administration approval expanded indications to a BMI < 40 kg/m2. There is a wide variability in body fat distribution. This study sought to determine if neck circumference is a better surrogate predictive variable for HGNS outcomes than BMI. METHODS: A retrospective chart review was conducted at a tertiary care center on adults who underwent HGNS implantation by a single surgeon from March 2017 to October 2021. Baseline demographic data including neck circumference, diagnostic sleep studies and post-implantation HGNS titration studies were collected. Linear regression and Spearman's Correlation Coefficient (SCC) analysis were utilized to compare neck circumference (NC), percentage of predicted neck circumference (PPNC) and BMI with the apnea-hypopnea index at effective voltage (AHI-v). RESULTS: This study included 43 patients who were middle aged (61.1 years), predominantly male (76.7%), with severe obstructive sleep apnea (median AHI 35) and mean neck circumference of 15.3 inches. Utilizing the NC and PPNC, positive correlations with AHI-v were observed (p = 0.0033, SCC = .438, and p = 0.0029, SCC = .444). While controlling for BMI, a 1-inch increase in neck circumference was associated with a 35% increase in AHI-v (p = 0.0411). CONCLUSIONS: A larger neck circumference was independently associated with worse HGNS outcomes. Further research is needed to support and confirm these findings, particularly across sexes.

Prospective trial of efficacy and safety of ondansetron and fluoxetine in patients with obstructive sleep apnea syndrome.

STUDY OBJECTIVE: Incremental withdrawal of serotonin during wake to sleep transition is postulated as a key mechanism that renders the pharyngeal airway collapsible. While serotonin promotion with reuptake inhibitors have demonstrated modest beneficial effects during NREM sleep on obstructive sleep apnea (OSA), animal studies suggest a potential therapeutic role for selective serotonin receptor antagonists (5-HT3) in REM sleep. We aimed to test the hypothesis that a combination of ondansetron (Ond) and fluoxetine (Fl) may effectively reduce expression of disordered breathing during REM and NREM sleep in patients with OSA. DESIGN AND SETTING: A prospective, parallel-groups, single-center trial in patients with OSA. PARTICIPANTS: 35 adults with apnea hypopnea index (AHI) > 10; range 10-98. INTERVENTION: Subjects were randomized to placebo, n = 7; Ond (24 mg QD), n = 9; Fl (5 mg QD) + Ond (12 mg QD), n = 9; and Fl (10 mg QD) + Ond (24 mg QD), n = 10. MEASUREMENTS AND RESULTS: AHI was measured by in-lab polysomnography after a 7-day no-treatment period (Baseline) and on days 14 and 28 of treatment. The primary endpoint was AHI reduction at days 14 and 28. OND+FL resulted in approximately 40% reduction of baseline AHI at days 14 and 28 (unadjusted P < 0.03 for each) and improved oximetry trends. This treatment-associated relative reduction in AHI was also observed in REM and supine sleep. CONCLUSIONS: Combined treatment with OND+FL is well-tolerated and reduces AHI, yielding a potentially therapeutic response in some subjects with OSA.

Continuous positive airway pressure device-based automated detection of obstructive sleep apnea compared to standard laboratory polysomnography.

PURPOSE: Obstructive sleep apnea (OSA) is a common health problem that affects more than 2-4% of the US population. Polysomnography (PSG) is the gold standard for diagnosing OSA. PSG is, however, expensive, time-consuming, and not always readily accessible. Hence, alternative diagnostic methods such as home-based testing have been evaluated. We studied the ability of the REMstar Pro (RSP2, a brand of continuous positive airway pressure (CPAP) device) to identify abnormal breathing events in subjects with OSA and compared this with breathing events simultaneously determined by laboratory-based PSG. METHODS: We evaluated 10 subjects previously diagnosed with OSA (apnea hypopnea index (AHI) > 15, known therapeutic level of CPAP). Subjects underwent attended PSG using the REMstar Pro M series machine and their prescribed interface/mask type. The first 3 h of the study were conducted using a subtherapeutic CPAP (4 cm H2O). The last 3 h or remaining portion of the PSG was completed using the previously determined therapeutic CPAP. Comparison of respiratory events detected by PSG vs the RSP2 was performed. RESULTS: Subjects included four men and six women, aged 32 to 57 years and with a body mass index ranging from 29.5-66.4. The baseline AHI ranged from 18.3-93.1, with the AHI at therapeutic CPAP ranging from 0-3. Apnea counts at baseline and at therapeutic CPAP by manually scored PSG and REMstar were not significantly different (mean at subtherapeutic 11.7 vs 12.5, p = 0.76; median at therapeutic CPAP 2.0 vs 4.5, p = 0.15). Hypopnea counts at baseline and at effective CPAP by PSG and REMstar were not significantly different (mean at subtherapeutic 38.1 vs. 40.9, p = 0.72; median at therapeutic CPAP 5.0 vs. 2.5, p = 0.34). The correlation coefficient of REMstar and PSG for apnea and hypopnea was significant in subtherapeutic phase only (apnea r = 0.78, p = 0.007; hypopnea r = 0.76, p = 0.01). Agreement between the two methods declined for hypopnea detection at therapeutic CPAP. CONCLUSIONS: The monitoring of residual sleep-disordered breathing on treatment, in addition to adherence, is an important objective therapeutic target in OSA. The REMstar Pro detects sleep-disordered breathing events similar to that of a manually scored PSG-for apnea but not for hypopnea-and merits further investigation as a device to determine disease severity and treatment efficacy.

Obstructive Sleep Apnea Is Associated with Newly Diagnosed Gestational Diabetes Mellitus.

Rationale: Sleep-disordered breathing (SDB) is associated with increased risk of adverse pregnancy outcomes, including gestational diabetes mellitus (GDM). GDM is a significant cause of maternal and infant morbidities. Assessing these risk factors concurrently may facilitate both the identification of women at GDM risk and the initiation of GDM prevention strategies.Objectives: To investigate whether SDB events, including SDB in rapid eye movement (REM) sleep and other sleep parameters, are associated with increased risk of GDM and to evaluate the performance of the models investigating associations between breathing and sleep parameters and GDM risk.Methods: In this case-control study, 46 women with newly diagnosed GDM and 46 healthy control subjects, who were individually matched for age, gestational age, body mass index, race, and parity, completed overnight polysomnographic studies and sleep questionnaires after being screened for GDM during the late-second to mid-third trimesters. Conditional logistic regression analysis was used to identify models investigating associations between risk factors and GDM risk. The Bayesian information criterion (BIC) was employed to compare models; the model with the lowest BIC is preferred.Results: Obstructive sleep apnea (OSA; defined as an apnea-hypopnea index [AHI] >5 events/h) was present in 22% of subjects with GDM and 9% of control subjects (P < 0.001). Women with OSA had a higher GDM risk (odds ratio [OR], 4.71; 95% confidence interval [CI], 1.05-21.04). In individual models, GDM risk was also significantly higher among women with higher overall AHI (events/h OR, 1.81; 95% CI, 1.01-3.27), higher AHI in REM (events/h OR, 2.09; 95% CI, 1.02-4.31), higher oxygen desaturation index greater than or equal to 4% (ODI4; events/h OR, 2.21; 95% CI, 1.03-4.73), and higher Sleep Apnea Symptom Score (OR, 2.72; 95% CI, 1.11-6.69). The percentage of non-REM sleep was significantly associated with decreased risk of GDM (percentage of non-REM sleep OR, 0.88; 95% CI, 0.78-0.99). The BIC supports the conclusion that there is a strong association between AHI in REM and GDM risk compared with the other significant models.Conclusions: SDB events, including REM-related OSA, are linked to increased GDM risk. GDM risk is also influenced by intercorrelated sleep variables.

Patients with chronic rhinosinusitis and obstructive sleep apnea have increased paroxysmal limb movement.

BACKGROUND: Patients with chronic rhinosinusitis (CRS) frequently experience sleep disruption and are at a higher than normal risk for obstructive sleep apnea (OSA). The purpose of this study was to determine how CRS affects polysomnography findings and sleep-related breathing in OSA. METHODS: A cohort study was performed that included 107 adult patients with CRS and comorbid OSA (CRS+OSA group) and 137 patients with OSA and without CRS as the control group. An electronic medical records database was used to identify eligible subjects. Comorbid conditions and polysomnography data were compared between the two groups by using logistic and linear regression analyses. RESULTS: A total of 246 patients were included: 107 patients in the CRS+OSA group and 137 patients with OSA and without CRS in the control group. After adjusting for demographic factors, the patients in the CRS+OSA group had a lower body mass index (BMI) and higher age at the time of diagnosis of OSA (p < 0.001). The patients in the CRS+OSA group had higher odds of having asthma and eczema. There was an increase in the periodic limb movement (PLM) index in the CRS+OSA group. Apnea and hypopnea indices were similar in the two groups. CONCLUSION: Patients with CRS developed OSA at a lower BMI; patients CRS and OSA had similar sleep-related breathing patterns but higher risks for PLMs compared with patients with OSA and without CRS.

Short-term outcome in the first 10 morbidly obese adolescent patients in the FDA-approved trial for laparoscopic adjustable gastric banding.

BACKGROUND: We received the LAP-BAND Investigational Device Exemption (IDE) from the US Food and Drug Administration in December 2004 to conduct a prospective longitudinal trial examining the safety and efficacy of laparoscopic adjustable gastric banding (LAGB) in morbidly obese adolescents ages 14 to 17 years. OBJECTIVES: To report the short-term results of LAGB in the first 10 adolescents with complete 9 months of follow-up. PATIENTS AND METHODS: Baseline characteristics and outcome data were analyzed in 10 patients enrolled between March 2005 and February 2006. RESULTS: All of the patients were girls. Their mean body mass index (+/-SD) was 50 +/- 13 kg/m, and excess weight was 171 +/- 79 pounds. Comorbidities included depression (3 patients), sleep apnea (3), hypertension (6), dyslipidemia (7), insulin resistance (9), metabolic syndrome (9), and steatohepatitis (in 4 of 5 patients with liver biopsy). Operative time was 45 +/- 9 minutes, and discharges were within 23 hours of surgery. Band-related complications were as follows: 2 dehydration, 1 pouch dilation, and 1 port revision. All of the patients lost weight, with a 9-month excess weight loss of 30% +/- 16% (range 14%-57%). Hypertension and the metabolic syndrome were resolved in 100% of patients (P = 0.04) and 80% of the patients (P = 0.01), respectively, along with significant improvement in the Pediatric Quality of Life and Beck Depression Inventory scores and a trend toward improvement in high-density lipoprotein cholesterol abnormalities (P = 0.08). CONCLUSIONS: At short-term follow-up, weight loss occurred with minimal complications, leading to early resolution of major obesity-related comorbidities. Continued evaluation of the long-term safety and efficacy of LAGB as a surgical adjunct to a comprehensive obesity treatment program is warranted.

Actigraphy scoring for sleep outcome measures in chronic obstructive pulmonary disease.

BACKGROUND: Actigraphy is commonly used to measure sleep outcomes so that sleep can be measured conveniently at home over multiple nights. Actigraphy has been validated in people with sleep disturbances; however, the validity of scoring settings in people with chronic medical illnesses such as chronic obstructive pulmonary disease remains unclear. The purpose of this secondary analysis was to compare actigraphy-customized scoring settings with polysomnography (PSG) for the measurement of sleep outcomes in people with chronic obstructive pulmonary disease who have insomnia. METHODS: Participants underwent overnight sleep assessment simultaneously by PSG and actigraphy at the University of Illinois of Chicago Sleep Science Center. Fifty participants (35 men and 15 women) with mild-to-severe chronic obstructive pulmonary disease and co-existing insomnia were included in the analysis. Sleep onset latency, total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE) were calculated independently from data derived from PSG and actigraphy. Actigraphy sleep outcome scores obtained at the default setting and several customized actigraphy settings were compared to the scored PSG results. RESULTS: Although no single setting was optimal for all sleep outcomes, the combination of 10 consecutive immobile minutes for sleep onset or end and an activity threshold of 10 worked well. Actigraphy overestimated TST and SE and underestimated WASO, but there was no difference in variance between PSG and actigraphy in TST and SE when the 10 × 10 combination was used. As the average TST and SE increased, the agreement between PSG and actigraphy appeared to increase, and as the average WASO decreased, the agreement between PSG and actigraphy appeared to increase. CONCLUSION: Results support the conclusion that the default actigraphy settings may not be optimal for people with chronic obstructive pulmonary disease and co-existing insomnia.

Type 2 diabetes, glycemic control, and continuous positive airway pressure in obstructive sleep apnea.

BACKGROUND: Sleep-disordered breathing (SDB) is a prevalent condition associated with significant comorbidities, including hypertension, obesity, cardiovascular disease, and insulin resistance. It has been previously shown that the severity of insulin resistance is related to the severity of SDB. METHODS: Using a 72-hour continuous glucose monitoring system, we studied changes in interstitial glucose levels and measured hemoglobin A1c levels in 25 patients with type 2 diabetes mellitus before and after continuous positive airway pressure (CPAP) treatment for SDB. RESULTS: With a mean +/- SD CPAP treatment period of 83 +/- 50 days, the mean +/- SD 1-hour postprandial glucose values were significantly reduced for breakfast (191 +/- 68 mg/dL to 130 +/- 41 mg/dL [10.6 +/- 3.8 mmol/L to 7.2 +/- 2.3 mmol/L]), lunch (196 +/- 70 mg/dL to 138 +/- 49 mg/dL [10.9 +/- 3.9 mmol/L to 7.7 +/- 2.7 mmol/L]), and dinner (199 +/- 66 mg/dL to 137 +/- 48 mg/dL [11.0 +/- 3.7 mmol/L to 7.6 +/- 2.7 mmol/L]). In the 17 patients with a baseline hemoglobin A1c level greater than 7%, there was a significant reduction in hemoglobin A1c level (9.2% +/- 2.0% to 8.6% +/- 1.8%). Furthermore, in subjects who used CPAP for more than 4 h/d, the reduction in hemoglobin A1c level was significantly correlated with days of CPAP use. There was no such correlation in subjects who used CPAP for 4 h/d or less. CONCLUSIONS: These findings suggest that SDB is pathophysiologically related to impaired glucose homeostasis, and that CPAP can be an important therapeutic approach for diabetic patients with SDB.

Efficacy and mechanisms of behavioral therapy components for insomnia coexisting with chronic obstructive pulmonary disease: study protocol for a randomized controlled trial.

BACKGROUND: Difficulty falling asleep, staying asleep or poor-quality sleep (insomnia) is common in people with chronic obstructive pulmonary disease (COPD). Insomnia is related to greater mortality and morbidity, with four times the risk of mortality for sleep times below 300 min. However, insomnia medications are used with caution in COPD due to their potential adverse effects. While cognitive behavioral therapy for insomnia (CBT-I) is effective for people with primary insomnia and people with other chronic illnesses, the efficacy and mechanisms of action of such a therapy are yet unclear in people with both insomnia and COPD. The purpose of this study is to rigorously test the efficacy of two components of insomnia therapy - CBT-I and COPD education (COPD-ED) - in people with coexisting insomnia and COPD, and to identify mechanisms responsible for therapy outcomes. The rationale for the proposed study is that once the efficacy and mechanisms of CBT-I and COPD-ED are known, new and innovative approaches for insomnia coexisting with COPD can be developed to non-pharmacologically minimize insomnia and fatigue, thereby leading to longer, higher-quality and more productive lives for people with COPD, and reduced societal cost due to the effects of insomnia. METHODS: We are conducting a randomized, controlled, parallel-group (N = 35 each group) comparison of CBT-I, COPD-ED and non-COPD, non-sleep health education Attention Control (AC) using a highly efficient four-group design. Arm 1 comprises 6 weekly sessions of CBT-I + AC; Arm 2 = 6 weekly sessions of COPD-ED + AC; Arm 3 = 6 weekly sessions of CBT-I + COPD-ED; and Arm 4 = 6 weekly sessions of AC. This design will allow completion of the following specific aims: (1) to determine the efficacy of individual treatment components, CBT-I and COPD-ED, on insomnia and fatigue, (2) to define the mechanistic contributors to the outcomes after CBT-I and COPD-ED. DISCUSSION: The research is innovative because it represents a new and substantive departure from the usual insomnia therapy, namely by testing traditional CBT-I with education to enhance outcomes. The work proposed in aims 1 and 2 will provide systematic evidence of the efficacy and mechanisms of components of a novel approach to insomnia comorbid with COPD. Such results are highly likely to provide new approaches for preventive and therapeutic interventions for insomnia and fatigue in COPD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01973647 . Registered on 22 October 2013.

The effect of continuous positive airway pressure on glucose control in diabetic patients with severe obstructive sleep apnea.

Obstructive sleep apnea (OSA) is independently associated with glucose intolerance and insulin resistance, and recent studies have shown that continuous positive airway pressure (CPAP) improves insulin sensitivity. The objective of this study was to describe the change in glycosylated hemoglobin (HbA1c) after treatment with CPAP in patients with type 2 diabetes mellitus and OSA. To test this hypothesis, we performed a retrospective analysis of 38 patients seen in the sleep clinic of an urban public teaching hospital. All patients had OSA and type 2 diabetes mellitus, and their diabetic medication regimen had remained unchanged during the period of CPAP therapy. Sixty-one percent were men, body mass index was 42+/-9.5 kg/m(2), and the Apnea-Hypopnea Index was 53+/-36 per hour. HbA1c before therapy with CPAP was 7.8+/-1.4% and decreased to 7.3+/-1.3% after 134+/-119 days of therapy (p<0.001). Treatment with CPAP leads to a clinically significant drop in HbA1c in patients with type 2 diabetes mellitus and severe OSA.

Cognitive behavioral therapy for insomnia comorbid with COPD is feasible with preliminary evidence of positive sleep and fatigue effects.

BACKGROUND: Many people with COPD report difficulties falling asleep or staying asleep, insufficient sleep duration, or nonrestorative sleep. Cognitive behavioral therapy for insomnia (CBT-I) has proved effective not only in people with primary insomnia but also in people with insomnia comorbid with psychiatric and medical illness (eg, depression, cancer, and chronic pain). However, CBT-I has rarely been tested in those with COPD who have disease-related features that interfere with sleep and may lessen the effectiveness of such therapies. The purpose of this study was to determine the feasibility of applying a CBT-I intervention for people with COPD and to assess the impact of CBT-I on insomnia severity and sleep-related outcomes, fatigue, mood, and daytime functioning. METHODS: The study had two phases. In Phase 1, a 6-weekly session CBT-I intervention protocol in participants with COPD was assessed to examine feasibility and acceptability. Phase 2 was a small trial utilizing a prospective two-group pre- and post-test design with random assignment to the six-session CBT-I or a six-session wellness education (WE) program to determine the effects of each intervention, with both interventions being provided by a nurse behavioral sleep medicine specialist. RESULTS: Fourteen participants (five in Phase 1 and nine in Phase 2) completed six sessions of CBT-I and nine participants completed six sessions of WE. Participants indicated that both interventions were acceptable. Significant positive treatment-related effects of the CBT-I intervention were noted for insomnia severity (P = 0.000), global sleep quality (P = 0.002), wake after sleep onset (P = 0.03), sleep efficiency (P = 0.02), fatigue (P = 0.005), and beliefs and attitudes about sleep (P = 0.000). Significant positive effects were noted for depressed mood after WE (P = 0.005). CONCLUSION: Results suggest that using CBT-I in COPD is feasible and the outcomes compare favorably with those obtained in older adults with insomnia in the context of other chronic illnesses.

Prevalence of type 2 diabetes in patients with obstructive sleep apnea in a multi-ethnic sample.

STUDY OBJECTIVES: Relationship of obstructive sleep apnea (OSA) with insulin resistance and type 2 diabetes in Caucasians has been studied, but this association has not been investigated in Hispanic and African-Americans. The objective of this study is to determine the prevalence of type 2 diabetes in patients evaluated for OSA in a predominantly African American and Hispanic sample. The secondary objective is to evaluate the relationship of REM related OSA and type 2 diabetes. METHODS: 1008 consecutive patients who had a comprehensive polysomnography were evaluated. OSA was defined as an obstructive apnea-hypopnea index (AHI) of > or = 5 per hour. REM AHI of > or = 10 was considered to indicate REM related OSA. RESULTS: The prevalence of type 2 diabetes was 30.1% in the group with OSA compared to 18.6% in those without OSA. The subjects with OSA had significantly increased odds of type 2 diabetes compared with those without OSA (odds ratio = 1.8, 95% confidence interval: 1.3-2.6) but this association became non-significant when controlled for confounding variables and covariates (odds ratio = 1.3, 95% confidence interval: 0.9-2.0). Middle-aged participants with OSA had 2.8 times higher odds for type 2 diabetes, when compared to younger or middle aged without OSA, controlling for covariates. Finally, the odds of type 2 diabetes were 2.0 times higher in patients with REM AHI of > or = 10/h independent of confounding variables. CONCLUSIONS: OSA is not independently associated with type 2 diabetes in a predominantly African American and Hispanic sample. However, the relationship of REM related OSAwith type 2 diabetes may be statistically significant.

Sleep apnea in an urban public hospital: assessment of severity and treatment adherence.

OBJECTIVE: To assess obstructive sleep apnea (OSA) severity, continuous positive airway pressure (CPAP) adherence, and factors associated with CPAP adherence among a group of patients with OSA receiving care at a publicly funded county hospital. STUDY DESIGN AND SETTING: A retrospective cohort study in a 464-bed urban public hospital in Cook County, Illinois. RESULTS: A total of 507 patients were included. They had a mean (SD) age of 46.9(11) years, mean body mass index of 46.2 (11.0) kg/m2; mean and median baseline apnea-hypopnea index (AHI) of 71.0 (44.4) and 69.5 episodes/h; mean Epworth Sleepiness Scale (ESS) score of 15.8 (6.1). Of these patients, 53% were men, 74% did not have health insurance coverage, and 77% were African American. Mean CPAP adherence of the 323 patients with follow-up data was 3.87 (2.62) hours/ day, with 47.7% of subjects using CPAP objectively for > or = 4 hours/day. Women were 2.49 (95% CI, 1.39-4.46) times more likely to be nonadherent than men, after adjusting for race, marital status, and age. Of the 172 patients who did not follow up, there were disproportionately more men. When individuals without follow-up were assumed to be nonadherent, the overall compliance rate was 30.4%, and women were 1.72 (95% CI, 1.03-2.88) times more likely to be noncompliant than men, adjusting for race, marital status, and age. CONCLUSION: This study population experienced severe OSA. CPAP adherence was low, with women having a higher likelihood of nonadherence than men. With the epidemic of obesity and increased awareness of OSA, this population should be further studied to diminish future health disparities in the treatment of this disease.

Liver enzymes and histology in obese patients with obstructive sleep apnea.

BACKGROUND AND AIMS: Recent studies have shown an association between obstructive sleep apnea (OSA) and elevated liver enzymes in patients with nonalcoholic fatty liver disease (NAFLD). The aim of the current study was to compare biochemical and histologic findings in patients with NAFLD as a function of OSA status. METHODS: Subjects consisted of 85 patients who had a sleep study followed by a liver biopsy performed at the time of obesity surgery. The diagnosis of OSA was based on an apnea hypopnea index of >/=15. Demographic and laboratory data were collected retrospectively. Liver biopsies were systematically evaluated for features of NAFLD including degree of steatosis, inflammation, and fibrosis. RESULTS: All but one patient had histologic evidence of NAFLD and 51% of the study population had OSA. A higher proportion of patients with OSA had elevated alanine aminotransferase levels (13/39) compared with those without OSA (3/34) (P=0.01). Only 19% of subjects had fibrosis on liver biopsy and still fewer (5%) had bridging fibrosis or cirrhosis. There was a trend toward a higher prevalence of OSA in patients with evidence of progressive liver disease, as indicated by inflammation plus fibrosis (11/15), compared with those with inflammation alone (22/48) (P=0.06). CONCLUSIONS: In obese patients with NAFLD, OSA was associated with elevated alanine aminotransferase levels and a trend toward histologic evidence of progressive liver disease.

Impact of adherence with positive airway pressure therapy on hypercapnia in obstructive sleep apnea.

BACKGROUND: Daytime hypercapnia is common in morbidly obese patients with obstructive sleep apnea and is associated with serious complications. Our objective was to quantify the effect of adherence with positive airway pressure on hypercapnia and hypoxia in these patients. METHODS: We performed a retrospective cohort study of 75 patients using a multivariable general linear model analysis to identify variables that predicted changes in PaCO2 and PaO2 after therapy. Bootstrap resampling methods were used to calculate confidence intervals for the effects of significant predictors and to internally validate the predictive models. RESULTS: The variables that predicted the change in PaCO2 were average daily hours of positive pressure therapy, FEV1 percentage of predicted, and baseline PaCO2 (model R(2) = 0.70). The PaCO2 dropped 1.84 mm Hg per hour of adherence and plateaued at 7 hours of average daily use. The PaO2 improved by approximately 3 mm Hg per hour of adherence and plateaued after 4.5 hours of therapy (model R2 = 0.48). Patients who used therapy for more than 4.5 hours per day experienced significant improvements in PaCO2 and PaO2 compared with less-adherent patients (APaCO2 7.7+/-5 vs 2.4+/-4 mm Hg, p < .001; delta PaO2 9.2+/-11 vs 1.8+/-9 mm Hg, p < .001). For adherent patients, the need for daytime home oxygen therapy decreased from 30% to 6% (p = .02). CONCLUSION: In hypercapnic patients with obstructive sleep apnea, adherence with positive airway pressure is an important modifiable predictor of improvements in PaCO2 and PaO2, and its benefit plateaus between 5 and 7 hours of daily therapy.