The effect of sibutramine-assisted weight loss in men with obstructive sleep apnoea

Giving weight to incretin-based pharmacotherapy for obesity-related sleep apnea: a revolution or a pipe dream?

Obesity is a chronic disease affecting over 670 million adults globally, with multiple complications including obstructive sleep apnea (OSA). Substantial weight loss in patients with obesity-related OSA can reduce or even eliminate OSA as well as reduce sleepiness and improve cardio-metabolic health. Evidence suggests that these improvements exceed those that occur with device-based OSA therapies like continuous positive airway pressure which continue to be the first-line of therapy. Resistance to weight management as a first-line strategy to combat OSA could arise from the complexities in delivering and maintaining adequate weight management, particularly in sleep clinic settings. Recently, incretin-based pharmacotherapies including glucagon-like peptide 1 (GLP-1) receptor agonists alone or combined with glucose-dependent insulinotropic polypeptide (GIP) receptor agonists have been developed to target glycemic control in type 2 diabetes. These medications also slow gastric emptying and reduce energy intake. In randomized, placebo-controlled trials of these medications in diabetic and non-diabetic populations with obesity, participants on active medication lost up to 20% of their body weight, with corresponding improvements in blood pressure, lipid levels, physical functioning, and fat mass loss. Their adverse effects are predominantly gastrointestinal-related, mild, and transient. There are trials currently underway within individuals with obesity-related OSA, with a focus on reduction in weight, OSA severity, and cardio-metabolic outcomes. These medications have the potential to substantially disrupt the management of OSA. Pending coming data, we will need to consider pharmacological weight loss as a first-line therapy and how that influences training and management guidelines.

Prospects for new drugs to treat binge-eating disorder: Insights from psychopathology and neuropharmacology

BACKGROUND

Binge-eating disorder (BED) is a common psychiatric condition with adverse psychological and metabolic consequences. Lisdexamfetamine (LDX) is the only approved BED drug treatment. New drugs to treat BED are urgently needed.

METHODS

A comprehensive review of published psychopathological, pharmacological and clinical findings.

RESULTS

The evidence supports the hypothesis that BED is an impulse control disorder with similarities to ADHD, including responsiveness to catecholaminergic drugs, for example LDX and dasotraline. The target product profile (TPP) of the ideal BED drug combines treating the psychopathological drivers of the disorder with an independent weight-loss effect. Drugs with proven efficacy in BED have a common pharmacology; they potentiate central noradrenergic and dopaminergic neurotransmission. Because of the overlap between pharmacotherapy in attention deficit hyperactivity disorder (ADHD) and BED, drug-candidates from diverse pharmacological classes, which have already failed in ADHD would also be predicted to fail if tested in BED. The failure in BED trials of drugs with diverse pharmacological mechanisms indicates many possible avenues for drug discovery can probably be discounted.

CONCLUSIONS

(1) The efficacy of drugs for BED is dependent on reducing its core psychopathologies of impulsivity, compulsivity and perseveration and by increasing cognitive control of eating. (2) The analysis revealed a large number of pharmacological mechanisms are unlikely to be productive in the search for effective new BED drugs. (3) The most promising areas for new treatments for BED are drugs, which augment noradrenergic and dopaminergic neurotransmission and/or those which are effective in ADHD.

The impact of obstructive sleep apnea on endothelial function during weight loss in an obese pediatric population

BACKGROUND

Childhood obesity is an increasing problem with substantial comorbidities such as obstructive sleep apnea (OSA) and increased cardiovascular morbidity. Endothelial dysfunction is an underlying mechanism related to both obesity and OSA.

RESEARCH QUESTION

To investigate the effect of weight loss on endothelial function and OSA in obese children and to determine whether a change in endothelial function can be linked to an improvement in OSA.

METHODS

Obese children between 8 and 18 years of age were recruited while entering a 12-month inpatient weight loss program. Patients were followed at 3 study visits: baseline, after 10 months of weight loss, and 6 months after ending the program (18 months). Anthropometry and endothelial function (EndoPAT) were determined at all study visits. At baseline, sleep screening with a portable device (ApneaLink) was performed. This was repeated after 10 months if OSA was diagnosed at baseline.

RESULTS

At baseline, 130 children were included, of which 87 had OSA (67%). Seventy-two patients attended the follow-up visit at 10 months, and 28 patients attended the follow-up visit at 18 months. The BMI z-score decreased after 10 months (from 2.7 (1.4-3.4) to 1.7 (0.5-2.7); p < 0.001) and remained stable at 18 months. Endothelial function improved significantly after weight loss, evidenced by a shorter time to peak response (TPR) and higher reactive hyperemia index (p = 0.02 and p < 0.001), and remained improved after 18 months (p < 0.001 and p = 0.007). After 10 months of weight loss, 10 patients had residual OSA. These patients had a higher TPR at 10 months (225 (75-285)s) than those without OSA (135 (45-225)s) and patients with a normalized sleep study (105 (45-285)s; p = 0.02). Linear mixed models showed that more severe OSA was associated with a worse TPR at baseline and less improvement after weight loss.

CONCLUSION

Weight loss improves endothelial function in an obese pediatric population. However, even after weight loss, endothelial function improved less in the presence of OSA.

Obstructive Sleep Apnea as a Cardiovascular Risk Factor-Beyond CPAP

Patients with obstructive sleep apnea (OSA) experience repetitive partial or complete airway collapse during sleep resulting in nocturnal hypoxia-normoxia cycling, and are at increased cardiovascular risk. The number of apneas and hypopneas indexed per hour of sleep (apnea-hypopnea index) along with the associated intermittent hypoxia predict the increased cardiovascular risk; thus, their attenuation or prevention are objectives of OSA therapy. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA and, when effective, mitigates the apnea-hypopnea index and hypoxemia. As such, it is reasonable to expect CPAP would decrease cardiovascular risk. However, 3 recent randomized clinical trials of CPAP vs usual care did not show any significant effects of CPAP in attenuating incident cardiovascular events in patients with OSA. In this review, we discuss these studies in addition to potential complementary therapeutic options to CPAP (eg, neurostimulation) and conclude with suggested therapeutic targets for future interventional studies (eg, the autonomic nervous system). Although these areas of research are exciting, they have yet to be tested to any similar degree of rigour as CPAP.

Targeting Endotypic Traits with Medications for the Pharmacological Treatment of Obstructive Sleep Apnea. A Review of the Current Literature

Obstructive sleep apnea (OSA) is a highly prevalent condition with few therapeutic options. To date there is no approved pharmacotherapy for this disorder, but several attempts have been made in the past and are currently ongoing to find one. The recent identification of multiple endotypes underlying this disorder has oriented the pharmacological research towards tailored therapies targeting specific pathophysiological traits that contribute differently to cause OSA in each patient. In this review we retrospectively analyze the literature on OSA pharmacotherapy dividing the medications tested on the basis of the four main endotypes: anatomy, upper airway muscle activity, arousal threshold and ventilatory instability (loop gain). We show how recently introduced drugs for weight loss that modify upper airway anatomy may play an important role in the management of OSA in the near future, and promising results have been obtained with drugs that increase upper airway muscle activity during sleep and reduce loop gain. The lack of a medication that can effectively increase the arousal threshold makes this strategy less encouraging, although recent studies have shown that the use of certain sedatives do not worsen OSA severity and could actually improve patients' sleep quality.

Associations Between Obstructive Sleep Apnea and Measures of Arterial Stiffness

STUDY OBJECTIVES

The aim of this study was to determine whether severity measures of obstructive sleep apnea (OSA) are associated with arterial stiffness and central blood pressure (two important cardiovascular risk factors) in a large group of patients with OSA.

METHODS

Baseline data from six studies on OSA in which arterial stiffness and central aortic blood pressure measures were determined using applanation tonometry were pooled. Associations between measures of arterial stiffness (heart rate corrected augmentation index [AI75]), central aortic blood pressure (central systolic pressure [CSP] and heart rate corrected central augmentation pressure [CAP75]) and measures of OSA severity were explored using stepwise regression modelling.

RESULTS

Data from 362 participants (M:F ratio 13:1) with mean (standard deviation) age 49.2 (11.0) years, body mass index 31.9 (5.3) kg/m², apnea-hypopnea index (AHI) 35.7 (20.7) events/h were included in the analyses. The AHI, oxygen desaturation index (ODI3%), and sleep time with SpO₂ < 90% (T90) were all associated with arterial stiffness (AI75), (AHI: adj. β = .069; P = .01; ODI3%: adj. β = .072; P = .01; T90: adj. β = .18; P < .0001) and CAP75 (AHI: adj. β = .030; P = .01; ODI3%: adj. β = .027; P = .02; T90: adj. β = .080; P < .0001). AHI was also associated with CSP (AHI: adj. β = .11; P = .002).

CONCLUSIONS

OSA severity was significantly associated with augmentation index and CAP75 although the relationships were not strong.

Effects of obesity therapies on sleep disorders

Obesity is a significant risk factor for obstructive sleep apnea syndrome (OSAS), and has also been linked to reductions in sleep quality and quantity. Weight loss has been shown to be an effective treatment for improving OSAS; however, there is a high degree of variability in improvements of OSAS in response to weight loss. There are three modalities of obesity therapies: 1) lifestyle modification, which includes changes in dietary intake and physical activity, along with behavioral interventions; 2) pharmacologic agents; and 3) bariatric surgery. Individuals have a highly variable response to the various obesity interventions, and maintenance of weight loss can be especially challenging. These factors influence the effect of weight loss on sleep disorders. There is still a need for large, well-controlled studies examining short- and long-term efficacy of weight loss modalities and their impact on long-term treatment of OSAS and other sleep parameters, particularly in youth. Nonetheless, given our current knowledge, weight reduction should always be encouraged for people coping with obesity, OSAS, and/or sleep disruptions and resources identified to assist patients in choosing a weight loss approach that will benefit them the most.

Obesity metabolic and hormonal disorders associated with obstructive sleep apnea and their impact on the risk of cardiovascular events

OBJECTIVE

To analyze metabolic and hormonal disorders resulting from the association between obesity and obstructive sleep apnea (OSA) syndrome that predispose to cardiovascular diseases and investigate the clinical benefits obtained from treatment approaches for both conditions.

METHODS

A literature review between 1997 and 2017 was conducted in the PubMed search database.

RESULTS

Obesity is the most important risk factor for OSA, and the progressive increase in its prevalence also affects OSA incidence. In addition, OSA may aggravate weight gain and obesity comorbidities. Both conditions lead to an increase in the risk of cardiovascular events and mortality. The gold standard treatment for moderate to severe OSA is CPAP, but significant reduction in major cardiovascular events was not observed in clinical trials. Body weight reduction appears effective to improve OSA, as long as it is maintained. Lifestyle modifications and drug therapy seem to be the preferred approach to treat obesity, but in severe obesity and moderate to severe OSA, bariatric surgery is probably the most adequate treatment.

CONCLUSIONS

Weight control is essential to decrease the risk of cardiovascular events and mortality potentially linked to both obesity and OSA. CPAP seems to treat only OSA without decreasing these risks. Other treatment strategies are lifestyle modifications and drug therapy, which need further investigation as well as bariatric surgery for severe cases.

Effect of liraglutide 3.0 mg in individuals with obesity and moderate or severe obstructive sleep apnea: the SCALE Sleep Apnea randomized clinical trial

BACKGROUND

Obesity is strongly associated with prevalence of obstructive sleep apnea (OSA), and weight loss has been shown to reduce disease severity.

OBJECTIVE

To investigate whether liraglutide 3.0 mg reduces OSA severity compared with placebo using the primary end point of change in apnea-hypopnea index (AHI) after 32 weeks. Liraglutide's weight loss efficacy was also examined.

SUBJECTS/METHODS

In this randomized, double-blind trial, non-diabetic participants with obesity who had moderate (AHI 15-29.9 events h(-1)) or severe (AHI ⩾30 events h(-1)) OSA and were unwilling/unable to use continuous positive airway pressure therapy were randomized for 32 weeks to liraglutide 3.0 mg (n=180) or placebo (n=179), both as adjunct to diet (500 kcal day(-1) deficit) and exercise. Baseline characteristics were similar between groups (mean age 48.5 years, males 71.9%, AHI 49.2 events h(-1), severe OSA 67.1%, body weight 117.6 kg, body mass index 39.1 kg m(-2), prediabetes 63.2%, HbA1c 5.7%).

RESULTS

After 32 weeks, the mean reduction in AHI was greater with liraglutide than with placebo (-12.2 vs -6.1 events h(-1), estimated treatment difference: -6.1 events h(-1) (95% confidence interval (CI), -11.0 to -1.2), P=0.0150). Liraglutide produced greater mean percentage weight loss compared with placebo (-5.7% vs -1.6%, estimated treatment difference: -4.2% (95% CI, -5.2 to -3.1%), P<0.0001). A statistically significant association between the degree of weight loss and improvement in OSA end points (P<0.01, all) was demonstrated post hoc. Greater reductions in glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) were seen with liraglutide versus placebo (both P<0.001). The safety profile of liraglutide 3.0 mg was similar to that seen with doses ⩽1.8 mg.

CONCLUSIONS

As an adjunct to diet and exercise, liraglutide 3.0 mg was generally well tolerated and produced significantly greater reductions than placebo in AHI, body weight, SBP and HbA1c in participants with obesity and moderate/severe OSA. The results confirm that weight loss improves OSA-related parameters.

Relationships between nutritional knowledge, obesity, and sleep disorder severity

Obstructive sleep apnea affects 20% of the adult population. Weight control is considered the best non-medical means of managing the condition, therefore improving nutritional knowledge in individuals may be an appropriate strategy. This study aimed to describe the relationship between nutritional knowledge and: (i) sleep disorder severity; (ii) body mass index; and (iii) demographic characteristics in persons suspected of obstructive sleep apnea. Nutrition knowledge scores were also compared with the general population. Consecutive newly-referred patients attending the sleep laboratory for diagnostic polysomnography were invited to participate. Those who consented (n = 97) were asked to complete a touchscreen survey. Apnea-hypopnea index to measure sleep disorder severity and anthropometric measurements were obtained from the clinic. A quarter of participants were diagnosed with severe obstructive sleep apnea; and a majority (88%) were classed as being overweight or obese. The overall mean nutrition knowledge score was 58.4 ± 11.6 (out of 93). Nutrition knowledge was not associated with sleep disorder severity, body mass index or gender. The only significant difference detected was in relation to age, with older (≥35 years) participants demonstrating greater knowledge in the 'food choices' domain compared with their younger counterparts (18-34 years; P < 0.030). Knowledge scores were similar to the general population. The findings suggest that nutrition knowledge alone is not an important target for weight control interventions for people with obstructive sleep apnea. However, given the complexities of sleep disorders, it may complement other strategies.

Bariatric Surgery or Non-Surgical Weight Loss for Obstructive Sleep Apnoea? A Systematic Review and Comparison of Meta-analyses

BACKGROUND

Obstructive sleep apnoea (OSA) is a well-recognised complication of obesity. Non-surgical weight loss (medical, behavioural and lifestyle interventions) may improve OSA outcomes, although long-term weight control remains challenging. Bariatric surgery offers a successful strategy for long-term weight loss and symptom resolution.

OBJECTIVES

To comparatively appraise bariatric surgery vs. non-surgical weight loss interventions in OSA treatment utilising body mass index (BMI) and apnoea-hypopnoea index (AHI) as objective measures of weight loss and apnoea severity.

METHODS

A systematic literature review revealed 19 surgical (n = 525) and 20 non-surgical (n = 825) studies reporting the primary endpoints of BMI and AHI before and after intervention. Data were meta-analysed using random effects modelling. Subgroup analysis, quality scoring and risk of bias were assessed.

RESULTS

Surgical patients had a mean pre-intervention BMI of 51.3 and achieved a significant 14 kg/m(2) weighted decrease in BMI (95%CI [11.91, 16.44]), with a 29/h weighted decrease in AHI (95%CI [22.41, 36.74]). Non-surgical patients had a mean pre-intervention BMI of 38.3 and achieved a significant weighted decrease in BMI of 3.1 kg/m(2) (95%CI [2.42, 3.79]), with a weighted decrease in AHI of 11/h (95%CI [7.81, 14.98]). Heterogeneity was high across all outcomes.

CONCLUSIONS

Both bariatric surgery and non-surgical weight loss may have significant beneficial effects on OSA through BMI and AHI reduction. However, bariatric surgery may offer markedly greater improvement in BMI and AHI than non-surgical alternatives. Future studies must address the lack of randomised controlled and comparative trials in order to confirm the exact relationship between metabolic surgery and non-surgical weight loss interventions in OSA resolution.

Maxillomandibular Volume Influences the Relationship between Weight Loss and Improvement in Obstructive Sleep Apnea

STUDY OBJECTIVES

Obesity is the major risk factor for OSA; however, weight loss reduces OSA to a variable extent. We aimed to assess whether size of the maxillomandibular skeletal enclosure influences the relationship between weight loss and OSA reduction.

METHODS

Obese males (≥ 30 kg/m2) with moderate-severe OSA (AHI > 15/h) participating in a 6-mo open-label weight loss program had craniofacial computed tomography (CT) scans before and after weight loss. CT scans were analysed using three-dimensional cephalometry. Maxillomandibular volume was calculated from skeletal landmarks on the mandible (condyle, gonion, menton) and maxilla (anterior nasal spine). Multiple regression analysis was used to test for moderating effects of maxillomandibular volume on relationship between changes in weight and apnea-hypopnea index (AHI).

RESULTS

Fifty-two men (age 44.3 ± 8.8 y, AHI 42.9 ± 21.3 events/h, body mass index [BMI] 34.0 ± 2.7 kg/m2) had 7.4 ± 4.1% weight loss and 34.1 ± 32.4% AHI reduction at 6 months. BMI reduction modestly predicted AHI change (r2 = 0.17, P = 0.002). The interaction term of maxillomandibular volume and BMI change was a predictor of OSA improvement (P = 0.03), indicating maxillomandibular volume moderates this relationship. Subgroup analyses of patients by small, medium, and large maxillomandibular volume showed a strong correlation between weight loss and OSA improvement only in the small volume group (r = 0.654, P = 0.004). There was no relationship evident in those with large maxillomandibular volume (r = 0.05, P = 0.9).

CONCLUSION

Maxillomandibular volume influences the relationship between weight loss and OSA improvement with an effect on AHI more evident in those with a smaller craniofacial skeleton.

Obstructive sleep apnoea syndrome

Obstructive sleep apnoea syndrome (OSAS) is a common clinical condition in which the throat narrows or collapses repeatedly during sleep, causing obstructive sleep apnoea events. The syndrome is particularly prevalent in middle-aged and older adults. The mechanism by which the upper airway collapses is not fully understood but is multifactorial and includes obesity, craniofacial changes, alteration in upper airway muscle function, pharyngeal neuropathy and fluid shift towards the neck. The direct consequences of the collapse are intermittent hypoxia and hypercapnia, recurrent arousals and increase in respiratory efforts, leading to secondary sympathetic activation, oxidative stress and systemic inflammation. Excessive daytime sleepiness is a burden for the majority of patients. OSAS is also associated with cardiovascular co-morbidities, including hypertension, arrhythmias, stroke, coronary heart disease, atherosclerosis and overall increased cardiovascular mortality, as well as metabolic dysfunction. Whether treating sleep apnoea can fully reverse its chronic consequences remains to be established in adequately designed studies. Continuous positive airway pressure (CPAP) is the primary treatment modality in patients with severe OSAS, whereas oral appliances are also widely used in mild to moderate forms. Finally, combining different treatment modalities such as CPAP and weight control is beneficial, but need to be evaluated in randomized controlled trials. For an illustrated summary of this Primer, visit: http://go.nature.com/Lwc6te.

Impact of sleep-disordered breathing treatment on upper airway anatomy and physiology

Sleep-disordered breathing (SDB) is a major public health problem. Various anatomic, pathophysiologic, and environmental changes contribute to SDB. The successful treatment of SDB reverses many of these abnormal processes. The present article discusses the current clinical evidence that supports the reversibility and its potential application in the management of SDB. Continuous positive airway pressure reduces angiogenesis and inflammatory edema, increases pharyngeal size, and improves surrogate markers of vascular inflammation and tongue muscle fiber types. Mandibular advancement devices lead to favorable maxillary and mandibular changes, increase pharyngeal area, and improve hypertension. Uvulopalatopharyngoplasty increases posterior airway space and pharyngeal volume, reduces nasal and oral resistance, and lowers response to high CO2. Weight loss reduces nasopharyngeal collapsibility, critical closing pressure of the airway, apnea-hypopnea index, and improves oxygen saturations. Potential clinical benefits of these changes in the management of SDB and patient compliance with treatment are discussed.

A randomized, double-blind, placebo-controlled study of an oral, extended-release formulation of phentermine/topiramate for the treatment of obstructive sleep apnea in obese adults

STUDY OBJECTIVES

To evaluate safety and efficacy of phentermine 15 mg plus extended-release topiramate 92 mg for treatment of moderate to severe obstructive sleep apnea (OSA) in obese adults.

DESIGN

This phase 2, randomized, double-blind, placebo-controlled study included 2-week screening and 28-week treatment periods. Overnight polysomnography was performed at baseline, Week 8, and Week 28.

SETTING

Single-center study conducted from August 2008 to September 2009.

PARTICIPANTS

Forty-five subjects with moderate to severe OSA not receiving positive airway pressure (PAP) treatment with body mass index of 30-40 kg/m(2).

INTERVENTIONS

Subjects were randomized to receive placebo (n = 23) or phentermine 15 mg plus extended-release topiramate 92 mg (n = 22). Both groups received lifestyle-modification counseling.

MEASUREMENTS AND RESULTS

Primary endpoint, change in apnea-hypopnea index (AHI), significantly favored phentermine 15 mg plus extended-release topiramate 92 mg (-31.5 events/h, 95% CI: -40.0, -22.9) over placebo (-16.6 events/h, 95% CI: -25.0, -8.2) at Week 28 (P =0.0084). At Week 28, there was a 10.2% (95% CI: -12.7, -7.6; 10.8 kg, 95% CI: -13.5, -8.0) mean decrease in weight in the phentermine 15 mg plus extended-release topiramate 92 mg group compared with 4.3% (95% CI: -6.6, -2.0; 4.7 kg, 95% CI: -7.2, -2.2) in the placebo group (P = 0.0006) and a positive, significant (P = 0.0003) correlation between percent change in weight and change in AHI. Significant improvements in overnight oxygen saturation and reduction in blood pressure compared with placebo were observed. Phentermine 15 mg plus extended-release topiramate 92 mg was well tolerated with low adverse event rates.

CONCLUSIONS

Phentermine 15 mg plus extended-release topiramate 92 mg induced significant weight reductions and concomitant improvements in OSA and related symptoms vs placebo. This suggests weight loss mediated by phentermine 15 mg plus extended-release topiramate 92 mg may be useful in treatment of moderate to severe OSA in obese subjects unable or unwilling to comply with PAP treatment.

Obesity and obstructive sleep apnea--clinical significance of weight loss

Obesity is a major health burden that contributes to increased morbidity and mortality. Obesity is also the most important risk factor for obstructive sleep apnea (OSA); at least 70% of patients are obese. OSA as such, has been linked with increased cardiovascular morbidity and mortality, and OSA patients often display metabolic syndrome. The exact underlying mechanisms behind these associations are complex and not fully understood. In obese individuals, weight reduction and increased physical activity form cornerstones for the prevention and treatment of metabolic syndrome, and recent controlled intervention trials strongly suggest that weight reduction together with a healthy diet and increased physical activity may correct or at least improve the symptoms of OSA. However, regardless of promising results in terms of symptoms of OSA and the undoubted metabolic benefits of changing lifestyles, weight reduction as a treatment of OSA is still underrated by many clinicians. Based on the current knowledge, clinicians should revise their previous attitudes, including suspicions about weight reduction as an effective treatment for OSA patients. Nevertheless, we also need large well-controlled trials on the effects of different weight reduction programs among OSA patients to determine the overall efficacy of different treatment modalities and their long-term success.

Body compositional and cardiometabolic effects of testosterone therapy in obese men with severe obstructive sleep apnoea: a randomised placebo-controlled trial

BACKGROUND

The combination of male gender, obstructive sleep apnoea (OSA) and obesity magnifies cardiometabolic risk. There has been no systematic study evaluating whether testosterone therapy can improve cardiometabolic health in obese men with OSA by improving body composition, visceral abdominal fat and insulin sensitivity.

OBJECTIVE

To assess body compositional and cardiometabolic effects of testosterone treatment in obese men with severe OSA.

DESIGN

An 18-week randomised, double-blind, placebo-controlled and parallel group trial in 67 men.

METHODS

Participants (age=49 ± 12 years, apnoea hypopnoea index=39.9 ± 17.7 events/h, BMI=31.3 ± 5.2 kg/m(2)) were placed on a hypocaloric diet and received i.m. injections of either 1000 mg testosterone undecanoate (n=33) or placebo (n=34) for 18 weeks. Outcomes were the changes in body composition (total muscle mass, total and abdominal fat, total body dual-energy X-ray absorptiometry and computerised tomography (CT)), weight, insulin sensitivity (homeostasis model assessment), abdominal liver fat (CT), arterial stiffness (pulse wave analysis), resting metabolic rate and respiratory quotient (indirect calorimetry) and blood lipids and metabolic syndrome from baseline to week 18.

RESULTS

After 18 weeks, testosterone treatment increased insulin sensitivity (-1.14 units, 95% confidence interval (95% CI) -2.27 to -0.01, P<0.05), reduced liver fat (0.09 Hounsfield attenuation ratio, 95% CI 0.009 to 0.17, P=0.03) and increased muscle mass (1.6 kg, 95% CI 0.69 to 2.5, P=0.0009) to a greater extent than placebo. Other measures of body composition and regional adiposity as well as the number of participants with metabolic syndrome did not change. Testosterone also decreased arterial stiffness (augmentation index) by 3.2% (95% CI -6.01 to -0.46%, P=0.02) and decreased the respiratory quotient (95% CI -0.04, -0.08 to -0.001, P=0.04) after 18 weeks compared with placebo.

CONCLUSION

Eighteen weeks of testosterone therapy in obese men with OSA improved several important cardiometabolic parameters but did not differentially reduce overall weight or the metabolic syndrome. Longer term studies are required.

Effects of testosterone therapy on sleep and breathing in obese men with severe obstructive sleep apnoea: a randomized placebo-controlled trial

STUDY OBJECTIVES

High doses of short-term testosterone have been shown to acutely worsen sleep-disordered breathing in men with obstructive sleep apnoea (OSA). The effects of lower, near-conventional doses of testosterone in obese men with OSA may differ over the longer term but have not been systematically studied. We assessed sleep and breathing effects of near-conventional testosterone treatment as an adjunct to weight loss in obese men with severe OSA.

DESIGN

An 18-week randomized, double-blind, placebo-controlled, parallel group trial in 67 men.

INTERVENTIONS

All subjects were placed on a hypocaloric diet and then received intramuscular injections of 1000 mg testosterone undecanoate or placebo at 0, 6 and 12 weeks.

MEASUREMENTS AND RESULTS

Sleep and breathing were measured by nocturnal polysomnography at 0, 7 and 18 weeks. Testosterone, compared to placebo, worsened the oxygen desaturation index (ODI) by 10·3 events/h (95%CI, 0·8-19·8 events/h; P = 0·03) and nocturnal hypoxaemia (sleep time with oxygen saturation <90%, SpO(2) T90%) by 6·1% (95%CI, 1·5-10·6; P = 0·01) at 7 weeks. Testosterone therapy did not alter ODI (4·5, -5·4 to 14·4 events/h; P = 0·36) or SpO(2) T90% at 18 weeks (2·9, -1·9-7·7%; P = 0·23) compared to placebo. The testosterone treatment effects on ODI and SpO(2) T90% were not influenced by baseline testosterone concentrations (testosterone by treatment interactions, all P > 0·35). Blood testosterone concentrations did not correlate with ODI or SpO(2) T90% (all P > 0·19).

CONCLUSIONS

Testosterone therapy in obese men with severe OSA mildly worsens sleep-disordered breathing in a time-limited manner, irrespective of initial testosterone concentrations. This time-dependency was not related to testosterone concentrations.

TRIAL REGISTRATION

www.anzctr.org.au Identifier: ACTRN1260-6000404527.

Position paper on the management of patients with obstructive sleep apnea and hypertension: joint recommendations by the European Society of Hypertension, by the European Respiratory Society and by the members of European COST (COoperation in Scientific and Technological research) ACTION B26 on obstructive sleep apnea

This article is aimed at addressing the current state of the art in epidemiology, pathophysiology, diagnostic procedures and treatment options for appropriate management of obstructive sleep apnea (OSA) in cardiovascular (particularly hypertensive) patients, as well as for the management of cardiovascular diseases (particularly arterial hypertension) in OSA patients. The present document is the result of the work done by a panel of experts participating in the European Union COST (COoperation in Scientific and Technological research) ACTION B26 on OSA, with the endorsement of the European Respiratory Society (ERS) and the European Society of Hypertension (ESH). These recommendations are particularly aimed at reminding cardiovascular experts to consider the occurrence of sleep-related breathing disorders in patients with high blood pressure. They are at the same time aimed at reminding respiration experts to consider the occurrence of hypertension in patients with respiratory problems at night.

Obesity, obstructive sleep apnoea and metabolic syndrome

OSA is increasingly recognized as a major health problem in developed countries. Obesity is the most common risk factor in OSA and hence, the prevalence of OSA is undoubtedly rising given the epidemic of obesity. Recent data also suggest that OSA is highly associated with the metabolic syndrome, and it is postulated that OSA contributes to cardiometabolic dysfunction, and subsequently vasculopathy. Current evidence regarding the magnitude of impact on ultimate cardiovascular morbidity or mortality attributable to OSA-induced metabolic dysregulation is scarce. Given the known pathophysiological triggers of intermittent hypoxia and sleep fragmentation in OSA, the potential mechanisms of OSA-obesity-metabolic syndrome interaction involve sympathetic activation, oxidative stress, inflammation and neurohumoral changes. There is accumulating evidence from human and animal/cell models of intermittent hypoxia to map out these mechanistic pathways. In spite of support for an independent role of OSA in the contribution towards metabolic dysfunction, a healthy diet and appropriate lifestyle modifications towards better control of metabolic function are equally important as CPAP treatment in the holistic management of OSA.

Obesity and craniofacial structure as risk factors for obstructive sleep apnoea: impact of ethnicity

OSA is the result of structural and functional abnormalities that promote the repetitive collapse of the upper airway during sleep. This common disorder is estimated to occur in approximately 4% of men and 2% of women, with prevalence studies from North America, Australia, Europe and Asia indicating that occurrence is relatively similar across the globe. Anatomical factors, such as obesity and craniofacial morphology, are key determinants of the predisposition to airway collapse; however, their relative importance for OSA risk likely varies between ethnicities. Direct inter-ethnic studies comparing craniofacial phenotypes in OSA are limited. However, available data suggest that Asian OSA populations primarily display features of craniofacial skeletal restriction, African Americans display more obesity and enlarged upper airway soft tissues, while Caucasians show evidence of both bony and soft tissue abnormalities. Our recent comparison of Chinese and Caucasian OSA patients found for the same degree of OSA severity. Caucasians were more obese, and Chinese had more skeletal restriction. However, the ratio of obesity to craniofacial bony size (or anatomical balance, an important determinant of upper airway volume and OSA risk) was similar between Caucasians and Chinese OSA patients. Ethnicity appears to influence OSA craniofacial phenotype but furthermore the relative contribution of the anatomical factors underlying OSA risk. The skeletal restriction craniofacial phenotype may be particularly vulnerable to increasing obesity rates. Better understanding of craniofacial phenotypes encompassing ethnicity may help improve OSA recognition and treatment; however, further studies are needed to elucidate ethnic differences in OSA anatomical risk factors.

Sleep disorders in morbid obesity

The increasing prevalence of obesity has lead to an increase in the prevalence of sleep disordered breathing in the general population. The disproportionate structural characteristics of the pharyngeal airway and the diminished neural regulation of the pharyngeal dilating muscles during sleep predispose the obese patients to pharyngeal airway collapsibility. A subgroup of obese apneic patients is unable to compensate for the added load of obesity on the respiratory system, with resultant daytime hypercapnia. Weight loss using dietary modification and life style changes is the safest approach to reducing the severity of sleep apnea, but its efficacy is limited on the long run. Although it has inherent risks, bariatric surgery provides the most immediate result in alleviating sleep apnea. Obesity has been linked also to narcolepsy. The loss of neuropeptides co-localized in hypocretin neurons is suggested as the potential mechanism. Poor sleep quality, which leads to overall sleep loss and excessive daytime sleepiness has also become a frequent complaint in this population. Identifying abnormal nocturnal eating is critically important for patient care. Both sleep related eating disorder and night eating syndrome are treatable and represent potentially reversible forms of obesity.

Obstructive sleep apnoea syndrome and weight loss: review

Obstructive sleep apnoea (OSA) syndrome is common, and obesity is a major risk factor. Increased peripharyngeal and central adiposity result in increased pharyngeal collapsibility, through increased mechanical loading around the upper airway, reduced tracheal traction on the pharynx, and reduced neuromuscular activity, particularly during sleep. Significant and sustained weight loss, if achieved, is likely to be a useful therapeutic option in the management of OSA and may be attempted by behavioural, pharmacological, and surgical approaches. Behavioural therapy programs that focus on aspects such as dietary intervention, exercise prescription patients and general lifestyle counselling have been tested. Bariatric surgery is an option in the severely obese when nonsurgical measures have failed, and laparoscopic adjustable gastric banding and Roux-en-Y gastric bypass are the most commonly employed techniques in the United Kingdom. Most evidence for efficacy of surgery comes from cohort studies. The role of sibutramine in OSA in the obese patients has been investigated, however, there are concerns regarding associated cardiovascular risk. In this paper the links between obesity and OSA are discussed, and the recent studies evaluating the behavioural, pharmacological and surgical approaches to weight loss in OSA are reviewed.

Medical Therapy for Obstructive Sleep Apnoea

Obstructive Sleep Apnoea (OSA) is increasingly recognised as a condition that not only causes excessive daytime sleepiness, but is also an important cardiovascular risk factor. Treatment of OSA should include conservative measures such as weight loss and positional therapy, the nuances of which are discussed in this article. However this in itself is not sufficient treatment for most patients. The first line of treatment for OSA that is recommended across the entire spectrum of disease is continuous positive airway pressure (CPAP) therapy. Indications for initiating CPAP are discussed, as well as possible alternatives to CPAP such as surgery or dental devices. In initiating CPAP treatment, machine-patient interface needs to be carefully considered, as there is a wide range of masks available. Factors to be considered in the choice of CPAP machine and mode are discussed. Finally, patient-specific factors such as patient acceptance of treatment, common problems encountered in CPAP follow-up and the importance of patient education are addressed.

Orlistat after initial dietary/behavioural treatment: changes in body weight and dietary maintenance in subjects with sleep related breathing disorders

BACKGROUND

Sleep related breathing disorders (SRBD) are associated with increased morbidity and mortality and weight loss is recommended to overweight or obese patients with SRBD. However, maintenance of weight loss is difficult to achieve and strategies for weight loss maintenance is needed. Orlistat is a pharmacological agent that reduces the intestinal absorption of fat and may favour long-term weight maintenance.

OBJECTIVE

To examine the change in body weight and dietary intake during a 1-year treatment with orlistat after an initial weight loss in obese subjects with SRBD. Furthermore, to explore the dietary determinants of weight maintenance during treatment with orlistat.

METHODS

Men and women with SRBD aged 32-62 years (n=63) participated in a 3-month dietary intervention to increase intake of vegetables and fruit. After an initial weight loss of 3.4 kg they achieved a mean body mass index of 34.3±4.7 kg/m2. Subsequently they were treated with orlistat for 1 year. During this year, dietary and behavioural interventions to attain weight loss were provided in the course of 14 group sessions. Dietary intake, energy density and food choices were assessed with a food frequency questionnaire before and after orlistat treatment.

RESULTS

With orlistat, body weight decreased by a mean of 3.5 kg (95% CI 1.5, 5.5). The dietary E% from saturated fat, intake of fatty dairy products and energy density increased after 1 year while intakes of oils, fish and vegetables decreased (all P<0.05). After multivariate adjustments, weight loss was associated with E% protein (R2adj=0.19 [95% CI 0.10, 0.46]), and inversely associated with E% saturated fat (R2adj=0.20 [95% CI 0.12, 0.47]) and fatty dairy products (R2adj=0.23 [95% CI 0.12, 0.49]).

CONCLUSIONS

Orlistat induced further weight loss, but dietary compliance declined with time. Increasing dietary protein and restricting saturated fat and fatty dairy products may facilitate weight loss with orlistat.

Slow wave sleep in patients with respiratory failure

BACKGROUND

Slow wave sleep (SWS) has been theorized as reflecting a homeostatic sleep process and is considered a state of recuperation. SWS is reduced in obstructive sleep apnea (OSA) patients, but SWS has not been specifically studied in respiratory failure patients. The aim of this study is to investigate SWS in predominantly hypercapnic respiratory failure patients.

METHODS

We analyzed sleep and arterial blood gas records of all 97 respiratory failure patients who underwent polysomnography and bilevel non-invasive ventilation (NIV) treatment in our laboratory from 2008 to July 2009. We also analyzed 32 initial diagnostic study data from these 97 patients.

RESULTS

The 97 patients had an average age of 58±15 (SD) years. Total sleep time was 320.3±82.8 (SD) min of which 32.9%±15.4 (%) was spent in SWS. This high percentage SWS correlated positively with awake arterial CO(2) pressure (PCO(2)) in both the 97 treatment studies (r=0.35, p=0.001) and the 32 initial diagnostic studies (r=0.40, p=0.025). The relationship was particularly apparent in patients with obesity hypoventilation syndrome or overlap syndrome. Statistical modelling identified three significant predictor variables for SWS across both diagnostic and NIV nights: PCO(2), arousal index and female gender.

CONCLUSIONS

Patients with respiratory failure have a high percentage of EEG assessed SWS which is in part determined by disease specific variables such as hypercapnia as well as by traditional SWS determinants such as sleep fragmentation and gender.

Sleep-disordered breathing and obesity: pathophysiology, complications, and treatment

Sleep-disordered breathing (SDB) is a medical condition that has increasingly recognized adverse health effects. Obesity is the primary risk factor for the development of SDB and contributes to cardiovascular and metabolic abnormalities in this population. However, accumulating evidence suggests that SDB may be related to the development of these abnormalities independent of obesity. Periodic apneas and hypopneas during sleep result in intermittent hypoxemia, arousals, and sleep disturbances. These pathophysiologic characteristics of SDB are likely mechanisms underlying cardiovascular and metabolic abnormalities including hypertension and other cardiovascular diseases, altered adipokines, inflammatory cytokines, insulin resistance, and glucose intolerance. Treatment of SDB with continuous positive airway pressure reverses some but not all of these abnormalities; however, studies to date have demonstrated inconsistent findings. Weight loss strategies, including diet, exercise, medications, and bariatric surgery, have been evaluated as a treatment strategy for SDB. In preliminary studies, dietary intervention and exercise reduced severity of SDB. One study demonstrated improvements in SDB severity using the weight-reducing medication sibutramine. In morbidly obese subjects, bariatric surgery effectively induces weight loss and improvement in SDB severity and symptoms, but long-term benefits remain uncertain. Large randomized trials are required to determine the utility of these strategies as long-term approaches to improving SDB and reducing associated complications.

Can improving sleep influence sleep-disordered breathing?

Sleep-disordered breathing (SDB) encompasses a group of disorders that include obstructive sleep apnoea (OSA), central sleep apnoea (CSA) and nocturnal hypoventilation. SDB commonly coexists with sleep disorders such as insomnia and restless legs syndrome, and sleep deprivation has been shown to play a role in the pathogenesis of SDB. Participants of a workshop, held at the 6th annual meeting of The International Sleep Disorders Forum: The Art of Good Sleep in 2008, evaluated whether the effective management of sleep disorders could result in a reduction in SDB. Following the workshop, a critical review of the literature in the field of sleep and SDB was conducted in order to assess the impact of improving sleep on SDB, and to determine whether measures taken to improve sleep result in a subsequent improvement in SDB. Results showed that studies evaluating the influence of improved sleep on respiratory abnormalities in patients with SDB are lacking. Studies in patients with OSA, with or without obesity-hypoventilation syndrome, show that therapy with continuous positive airways pressure and non-invasive ventilation improves sleep parameters with beneficial effects on SDB. Studies involving small numbers of patients have shown that the antidepressants fluoxetine and mirtazapine produce improvements in sleep parameters and the apnoea-hypopnoea index, and that acetazolamide may improve CSA. The benzodiazepines flurazepam, temazepam and nitrazepam, the hypnotic zolpidem, the melatonin receptor agonist ramelteon and gamma-hydroxybutyrate have all been shown to improve sleep, but are not associated with reductions or worsening in SDB. It is clear that there is a distinct knowledge gap with regard to the benefit of improving sleep disturbances for subsequent improvements in SDB. Randomized controlled clinical trials investigating the effect of pharmacological and non-pharmacological improvement of sleep disorders focusing on whether there is improvement in coexisting OSA/SDB are clearly needed. Furthermore, well-designed clinical trials investigating the role of hypnotic agents in improving SDB in certain phenotypes will enable the development of treatment recommendations for primary care physicians managing these patients in routine clinical practice.

The relationship of obesity and obstructive sleep apnea

Obstructive sleep apnea is a common disorder, and obesity is a known risk factor for its development. The prevalence of obesity is increasing worldwide, and a corresponding increase in the prevalence of obstructive sleep apnea and its cardiovascular and noncardiovascular consequences is likely. This article reviews the established evidence supporting obesity as a risk factor for obstructive sleep apnea and discusses the evidence suggesting that obesity is also a consequence of obstructive sleep apnea. There is evidence that treating obesity reduces the severity of obstructive sleep apnea and that treating obstructive sleep apnea decreases obesity. However, the evidence does not support a sustained correlation between weight loss and improvement in sleep-disordered breathing.

The use of sibutramine in the management of obesity and related disorders: an update

Aims:

To review the major trials that evaluated the efficacy and safety of the use of sibutramine for weight loss and the impact of this agent on obesity-related disorders.

Methods and results:

The most important articles on sibutramine up to January 2009 were located by a PubMed and Medline search. Sibutramine reduces food intake and body weight more than placebo and has positive effects on the lipid profile (mainly triglycerides and high density lipoprotein cholesterol), glycemic control and inflammatory markers in studies for up to one year. Preliminary studies showed that sibutramine may also improve other obesity-associated disorders such as polycystic ovary syndrome, left ventricular hypertrophy, binge eating disorder and adolescent obesity. The high discontinuation rates and some safety issues mainly due to the increase in blood pressure and pulse rate have to be considered. Additionally, it has not yet been established that treatment with sibutramine will reduce cardiovascular events and total mortality.

Conclusions:

Sibutramine, in conjunction with lifestyle measures, is a useful drug for reducing body weight and improving associated cardiometabolic risk factors and obesity-related disorders. Studies of longer duration are required to determine the precise indications of the drug, to evaluate safety issues and to assess its efficacy on cardiovascular mortality.

Clinical manifestations and consequences of obstructive sleep apnea

Obstructive sleep apnea is a common respiratory disorder that is underdiagnosed and associated with a variety of adverse health and safety consequences. Treatment is effective in improving quality of life and reducing morbidity. This underscores the importance of considering the diagnosis in suitable patients, verifying the diagnosis, and initiating prompt, effective therapy. In this review, the risk factors, symptoms and signs, diagnosis, clinical consequences, and treatment of obstructive sleep apnea are discussed.

Sibutramine-associated adverse effects: a practical guide for its safe use

Obesity is a multifactorial chronic disorder which comprises a serious health problem nowadays. The effective management of obesity is difficult in contemporary societies where abundance of hypercaloric food and sedentary lifestyle is the rule. Apart from lifestyle interventions, which include diet, exercise and behavioural treatment, weight-loss medications can also be used for the management of obesity. Sibutramine, a selective monoamine reuptake inhibitor, is a drug with established efficacy in sustained weight reduction and an overall favourable safety profile. However, its action on the sympathetic nervous system has linked sibutramine to blood pressure and heart rate elevations. These potentially adverse effects as well as other sibutramine-associated side effects and their possible underlying mechanisms are reviewed in the present article. Compelling evidence from the majority of data in the literature shows that sibutramine can be effectively used in conjunction with caloric restriction and exercise in obese patients. Hypertension, if adequately treated and frequently monitored, is not an absolute contraindication for the prescription of sibutramine.

Obesity and obstructive sleep apnea-hypopnea syndrome

Obstructive sleep apnea-hypopnea syndrome involves recurring episodes of total obstruction (apnea) or partial obstruction (hypopnea) of airways during sleep. Obstructive sleep apnea-hypopnea syndrome affects mainly obese individuals and it is defined by an apnea-hypopnea index of five or more episodes per hour associated with daytime somnolence. In addition to anatomical factors and neuromuscular and genetic factors, sleep disorders are also involved in the pathogenesis of sleep apnea. Obesity affects upper airway anatomy because of fat deposition and metabolic activity of adipose tissue. Obstructive sleep apnea-hypopnea syndrome and metabolic syndrome have several characteristics such as visceral obesity, hypertension and insulin resistance. Inflammatory cytokines might be related to the pathogenesis of sleep apnea and metabolic syndrome. Sleep apnea treatment includes obesity treatment, use of equipment such as continuous positive airway pressure, drug therapy and surgical procedures in selected patients. Currently, there is no specific drug therapy available with proven efficacy for the treatment of obstructive sleep apnea-hypopnea syndrome. Body-weight reduction results in improvement of sleep apnea, and obesity treatment must be emphasized, including lifestyle changes, anti-obesity drugs and bariatric surgery.

Two randomized placebo-controlled trials to evaluate the efficacy and tolerability of mirtazapine for the treatment of obstructive sleep apnea

OBJECTIVE

Mirtazapine is an a2A antagonist and mixed 5-HT2/5-HT3 antagonist that has been proposed as a potential treatment for obstructive sleep apnea (OSA). A small, randomized, controlled trial has previously found an approximate halving in the severity of OSA with daily doses of 4.5 and 15 mg. We aimed to confirm and extend these findings in 2 randomized placebo-controlled, proof-of-concept trials.

METHODS

Two randomized, double-blind, placebo-controlled trials of mirtazapine for OSA (apnea-hypopnea index 10-40/h). Study 1: 3-way crossover, dose-finding study testing the self-administration of mirtazapine (7.5, 15, 30, and/or 45 mg) or placebo 30 minutes prior to bedtime for 2 weeks at each dose. Twenty patients were randomly assigned to 1 of 6 different dose-sequence groups, with each patient exposed to a maximum of 3 doses. Study 2: 3-arm, randomized, parallel-group trial of mirtazapine at 15 mg or mirtazapine 15 mg + Compound CD0012 or placebo for 4 weeks in 65 patients with OSA.

RESULTS

Two patients withdrew from Study 1 after complaints of unacceptable lethargy. Fifteen patients were withdrawn from study 2, 7 after complaints of unacceptable lethargy or other side-effects. No measurement of sleep apnea improved due to mirtazapine in either study. Weight gain was significantly greater on mirtazapine than on placebo in both trials.

CONCLUSIONS

Mirtazapine did not improve sleep apnea in either trial. Mirtazapine caused weight gain, which may further worsen OSA. Therefore, mirtazapine is not recommended for the treatment of OSA.

Altered positional regulation of nasal patency in patients with obstructive sleep apnoea syndrome

We assessed the regulation of nasal patency supine in subjects with obstructive sleep apnoea syndrome (OSAS) compared to healthy controls. Healthy subjects increase nasal obstruction when changing body position from sitting to supine, possibly due to increased hydrostatic pressure in the head supine. Limited data indicate that this response is altered in patients with OSAS, suggesting that supine nasal patency is actively regulated. This study examined the nasal response to recumbent body position using acoustic rhinometry in OSAS patients and healthy controls. Twenty subjects (16 men and 4 women, mean age 55 +/- 16 years), with diagnosed OSAS [mean apnoea hypopnoea index (AHI) 46 +/- 22 events/h] without nasal obstruction and continuous positive airway pressure (CPAP)-naive, underwent measurement of intra-nasal cross sectional area by acoustic rhinometry at sitting and after 5 min supine. Twenty healthy controls (13 men, 7 women, mean age 35 +/- 9 years) were also included in the study. In the patients with OSAS, the mean minimal cross sectional area (MCA, left + right nasal cavity) was unchanged between sitting (1.18 +/- 0.41 cm(2)) and supine (1.21 +/- 0.35 cm(2), P = 0.5). In the healthy controls, the mean MCA decreased from 1.06 +/- 0.18 to 0.94 +/- 0.21 cm(2) supine, P = 0.01. This study showed that the normal decrease in nasal patency following a change in body position from sitting to supine is absent in patients with OSAS. The results indicate that there is an active regulation of supine nasal patency.

Obstructive sleep apnea in older adults

The "typical" presentation of obstructive sleep apnea (OSA) is chronic loud snoring and excessive daytime sleepiness in middle-aged obese men. OSA can result in increased risk for cardiovascular morbidity and mortality. The diagnostic features of OSA in older adults are similar to those in younger adults; however, the older adult may be less likely to seek medical attention or have the sleep disorder recognized because symptoms of snoring, sleepiness, fatigue, nocturia, unintentional napping, and cognitive dysfunction may be ascribed to the aging process itself or to other disorders. This article reviews the basic terminology and pathophysiology of sleep-disordered breathing, discusses why OSA may be even more prevalent in older adults than in the middle-aged group, and reviews similarities and differences between the two groups in the manifestations, consequences, and treatments of OSA.