Table 1.
Characteristics of included studies which evaluate the impact of OSA intervention on autonomic function (N = 43)
| Study | Study design, intervention type, and duration, and compliance | Participants N, % male, and age (mean, SD) | Baseline and treated AHI/AI/RDI (mean events/h, SD) | Inclusion and exclusion criteria | Autonomic measure/s (categories) |
|---|---|---|---|---|---|
| Roche et al. [38] | Before and during 1 night of CPAP (within subjects). | N = 38 (89.5% male), 52.2 years (11.2). | Baseline AHI mean 56.9 (SD 28.4). Treated AHI mean 3.8 (SD 5.4). |
Excluded: Permanent or paroxysmal atrial fibrillation, complete bundle branch blocks, shy-drager syndrome, use of antiarrhymic agents, and permanent venticular or atrial pacing. | HRV |
| Wu et al.[39] | Before and during 1 night of CPAP (within subjects). | N = 13, gender not stated, 53.8 years (SD 4.0). | Baseline AHI mean 62.7 (SD 5.8) Treated AHI not stated. |
Excluded: history of cardiac arrhythmias, congestive heart failure, myocardial infarction, ischemic heart disease, stroke, diabetes mellitus, central sleep apnea, restless legs syndrome, periodic limb movement disorder, chronic obstructive pulmonary disease. | HRV |
| Kufoy et al. [24] | Before and during 1 night of PAP (within subjects). | N = 39 (62% male), 51.4 years (SD 7.4). | Baseline AHI mean 47.7 (SD 15.1) Treated AHI not stated. |
Excluded: history of cardiovascular or cerebrovascular disease, sleep disorders, thyroid or endocrine disease including diabetes, use of antiarrhythmic, anticholinergic, or antidepressant medications. | HRV |
| Sukegawa et al. [40] | Before and during 1 night of CPAP (within subjects). | N = 17 (100% male), 53.7 years (SD 13.5). | Baseline AHI mean 42.5 (SD 25.9). Treated AHI mean 9.3 (SD 7.9). |
Not stated. | Catecholamines |
| Palma et al. [41] | Before and during 1 night of CPAP (within subjects). Before and after 2 years of CPAP (within subjects): Moderate OSA: CPAP use 2.1 (SD 0.8) years Severe OSA: CPAP use 1.9 (SD 0.7) years. Only compliant i.e. ≥4 h/night on 70% of nights included in study. |
Moderate OSA: n = 16 (81% male), 51.8 years (SD 13.4). Severe OSA: n = 14 (79% male), 52.3 years (SD 11.9). |
Moderate OSA: Baseline AHI mean 26.6 (SD 1.8). Acute treated AHI mean 4.2 (SD 6.4). Chronic treated AHI mean 7.6 (SD 3.9). Severe OSA: Baseline AHI mean 55.8 (SD 16.5). Acute treated AHI mean 3.9 (SD 8.1). Chronic treated AHI mean 6.1 (SD 3.4). |
Excluded:Psychiatric, craniofacial, respiratory or neurologic disorders; history of diabetes mellitus, coronary artery disease, arrhythmias, heart failure, or ST-T wave abnormalities; presence of other sleep disorders; smokers; patients taking cardiovascular medications, or medications known to affect the ANS. | HRV |
| Jennum et al. [42] | Before and after 8 days of PAP (within-subjects). Compliance not stated. |
N = 14 93% male 42 years (range 36–66). |
Baseline AHI mean 54.6 (SD 1.7). Treated AHI mean 13.2 (SD 15.8). |
Included: apnea index > 30/h, mean apnea time index > 20 s. Excluded: On medications during last half year, known medical or psychiatric disorders except hypertension. |
Catecholamines |
| Otsuka et al. [29] | Before and after 1 month of nCPAP treatment (within subjects). Compliance self-reported as “good”. |
N = 8 Gender not stated. Age not stated. |
Baseline AHI mean 86.3 (SD 29.3). Treated AHI mean 5.4 (SD 3.5). |
All patients were obese. Excluded:chronic obstructive pulmonary disease, primary cardiac diseases, daytime hypertension, antihypertensive medications, diabetes, hyper-and hypothyroidism, diseases of the liver and central nervous system. |
Iodine-123-MIBG imaging |
| Heitmann et al. [43] | Before and after 41.6 ± 16.9 days of CPAP (within subjects). Compliance 5.7 (SEM 0.7) h/night. |
N = 18 (gender not stated). Normotensive: 8 (gender not stated), 52.6 years (SD 10.1). Hypertensive: 10 (gender not stated), 47.9 years (SD 10.6). |
Normotensive: Baseline AHI mean 42.8 (SD 20.0). Treated AHI 0.3 (SD 0.7). Hypertensive: Baseline AHI mean 70.3 (SD 28.9). Treated AHI 0.4 (1.0). |
Excluded: systolic blood pressure > 220 mmHg or diastolic blood pressure > 110 mmHg; myocardial infarction; stroke; heart failure; neurological disease; or a history of alcohol or drug abuse; antihypertensive medication was discontinued at least 3 weeks before the study began. | Catecholamines |
| Schytz et al. [22] | Before and after 2 months or more of CPAP (within subjects). Days of CPAP ≥ 4 h 82 days (SEM 4 days). Days of usage 67 days (SEM 1 day). |
OSA patients n = 14, gender not stated, age not stated. | Baseline AHI and treated AHI not stated. | Excluded: history of stroke, myocardial infarction, stenosis of carotid arteries (>50%), unstable chronic lung disease, anemia, present cardiac arrhymia, central sleep apnea, REM sleep behavior disorder, narcolepsy, medication with effects on central nervous system. | Sympathetic activity measuredwith near-infrared spectroscopy (NIRS). |
| Tasali et al. [44] | Before and after 8 weeks of CPAP treatment (within subjects). CPAP compliance 6.6 h (SEM 0.4 h). Days not used over 8 week treatment period 3.4 days (SEM 1.2)Yy031272. |
N = 9 (0% male), 30.6 years (SD 1.7). | Baseline AHI mean 24.3 (SEM 5.5). Treated AHI mean 2.0 (SEM 1.0). |
All participants have polycystic ovary syndrome. | HRV |
| Quadri et al. [45] | Before and after 2 months of CPAP (within subjects). Compliance not stated. |
N = 12 (67% male), 58.0 years (SD 9.7). | Baseline AHI mean 45.4 (SD 14.9). Treated AHImean 7.1 (SD 7.7). |
Excluded:Presence of cardio-vascular, neurological, metabolic, and orthopedic co-morbidities and the use of beta-blockers therapy or any drug able to modify autonomic system function.OSAH treatment (bite, continuous positive airways pressure, surgery). | HRV |
| Roche et al. [46] | Before and after 3 months of CPAP (within subjects) Compliance not stated. |
N = 14 (86% male) 61.4 years (SD 8.1). | Baseline AHI mean 50.6 (SD 13.7). Treated AHI mean 2.2 (SD 2.5). |
Excluded: coronary artery disease, electrical left ventricular hypertrophy or ST-T wave abnormality, congestive heart failure, diabetes mellitus, beta blockers, antiarrythmic drugs, and digitalis. | HRV |
| Glos et al. [16] | Randomized cross-over trial of MAS and CPAP. Before and after 12 weeks of CPAP (within-subjects). Before and after 12 weeks of MAS (within-subjects). Compliance not stated. |
N = 40 (83% male), 49.5 years (SD 11.8). | Baseline AHI mean 28.5 (SD 16.5). MAS treated AHI mean 13.7 (SD 12.0). CPAP treated AHI mean 3.5 (SD 5.2). |
Excluded: drug abuse, medication that influences sleep, presence of other sleep disorders, history of any OSA treatment, psychiatric or neurological diseases, atrial fibrillation, any medication that could affect heart rate, craniomandibular disorders, acute/subacute dental conditions that affects treatment with mandibular advancement device, discontinuation of therapy for more than 1 week. | HRV Baroreflex function |
| Belozeroff et al. [6] | Before and after 6 months of CPAP (within subjects). Compares those compliant (>3 h/night; mean 6.2 h, SEM 0.9) and those non-compliant (<3 h/night, mean 0.7 h, SEM 0.2). |
N = 13 (100% male) Compliant: n = 6, (100% male) 48.5years (SE 4.2). Non-compliant: n = 7, (100% male) 44.1 years (SE 3.7). |
Compliant: Baseline AHI mean 87.8 (SE 15.6). Treated AHI not stated. Non-compliant: Baseline AHI mean 53.8 (SE 11.6) Treated AHI not stated. |
Excluded: diabetes, cardiac arrhythmia, congestive heart failure, lung disease. | HRV Baroreflex function |
| Fatouleh et al.[47] | Before and after 6 months, and after 12 months of CPAP (within subjects). Compliance not stated. |
N = 21 at baseline (86% male), 55 years (SD 2). N = 16 at 6 months (81% male), age not stated. N = 15 at 12 months (97% male), age not stated. |
Baseline AHI mean 44 (SD 5). Treated AHI not stated. |
Not stated. | MSNA |
| Fatouleh et al. [48] | Before and after 6 months of CPAP (within subjects). Compliance 6.0 (SEM 0.4) h/night. |
N = 11 (85% male), 53 years (SEM 3). | Baseline AHI mean 38 (SEM 5). Treated AHI mean 4 (SEM 2). |
Not stated. | MSNA |
| Lundblad et al. [49] | Before and after 6 months of CPAP (within subjects). Compliance 5.0 (SEM 0.4) h/night |
N = 13 (77% male), 54 years (SE 3). | Baseline AHI mean 41 (SEM 4). Treated AHI mean 3 (SEM 2). |
Not stated. | MSNA |
| Ferland et al. [18] | Pragmatic trial of sibutramine vs. CPAP. Before and after 1 year of sibutramine (within subjects). Compliance 91.7% (not defined). Before and after 1 year of CPAP(within subjects). Compliance 100% (not defined). |
N = 40 (88%). Sibutramine: n = 19 (86% male), 49 years (SD 9). CPAP: n = 16 (88% male), 49 years (SD 9). |
Sibutramine: Baseline AHI mean 54 (SD not stated). Treatment-baseline difference in AHI: −3 (SD 6). CPAP: Baseline AHI mean 52 (SD not stated). Treatment-baseline difference in AHI: −40 (SD 30). |
Included: untreated OSA, controlled systemic hypertension, type 2 diabetes, dyslipidaemia and/or visceral obesity. Excluded: uncontrolled systemic hypertension (>145/90mmHg), previous pharmacological or surgical treatment for weight loss, previous CPAP, severe diurnal hypersomnolence requiring immediate treatment. |
HRV |
| Shiina et al. [50] | Before and after 3 months of CPAP therapy. | N = 50 (90% Male), 54 years (SD 10). | Baseline AHI 54 (SD 22). After CPAP AHI not stated. |
Inclusion: patients with moderate to severe OSA. Exclusion: coronary artery disease, receiving insulin, receiving beta blockers. |
HRV Baroreceptor function |
| Waravdekar et al. [51] | Before and after 1 month compliance CPAP therapy (4.7 + −2.4 h/night). | N = 7 (86% male), 50 years (SD 11). | Baseline AHI mean 69 (SD 40). CPAP AHI not stated. |
Included: untreated OSA, all subjects were overweight (BMI 38.0 ± 5.1), snored, excessive daytime sleepiness, medications wer enot withheld or changed during the study period. Subject characteristics: 1× noninsulin-dependent DM and treated with oral hypoglycemic agent. 2× hypertensive treated with an angiotensin-converting enzyme inhibitor. |
MSNA |
| Bakker et al. [20] | Comparison of weight loss surgery and CPAP after 6, 12, 18 months of intervention (between subjects). CPAP usage not stated. |
Weight loss surgery: n = 12 (17% male), 43 (IQR 37, 49) years. CPAP: n = 15 (73% male), 48 (IQR 37, 52) years. |
Weight loss surgery: AHI at baseline 18.1 [IQR 16.3, 67.5], 6 months 10.5[5.0, 20.8], 12–18 months 6.5 [1.9, 12.8]. CPAP: Baseline AHI 36.5 [IQR 24.7, 77.3], 6 months 5.3 [1.6, 10.9], 12–18 months 3.8 [1.2, 10.6]. |
Included:BMI ≥ 30, free from cardiovascular co-morbidities. Excluded: smoking,presence of any cardiopulmonary, endocrine, or sleep disorders (other than OSA, consumption of any medications that could affect either cardiopulmonary function or sleep, including antihypertensive. |
HRV |
| Berger et al. [21] | Comparison of exercise training and no exercise training after 9 months of intervention (between subjects). | Exercise training: n = 36 (67% male), 52 [IQR 60–64] years. Control: n = 38 (58% male), 62 [IQR 60–65] years. |
Exercise training: AHI at baseline 22 (SD 7.0), 9 months 17 (SD 10). Control: AHI at baseline 21 (SD 6), 9 months 22 (10). |
Included: Cardiovascular history, hypertension, diabetes mellitus, current smoker, alcohol use, current medication (beta-blockers, other antihypertensive agent, antithrombotic agent, lipid-lowering agent, insulin or antidiabetic oral medication, psychotropic agents, hypothyroidism agent). Excluded: current OSA treatment, cardiovascular or respiratory comorbidities, and/or excessive daytime sleepiness justifying immediate initiation of CPAP, respiratory or heart disease contraindicating exercise discovery during stress testing, Parkinson’s disease.Frequent ectopic beats (>0.7%). |
HRV |
| Bonsignore et al. [52] | Comparison of before and after 3–14months of CPAP therapy. Average CPAP nightly 5 (SD 2) h. Mean treatment duration 6 (SD 4) months. |
N = 10 (100% Male), 47 (SD 9) years. | Baseline AHI 82 (SD 14). CPAP withdrawal AHI 63 (SD 26). |
Inclusion:office blood pressure > 140/90 mmHg, no clinical or laboratory evidence of chronic heart failure, hypertension, or other diseases causing autonomic dysfunction, no treatment with cardiovascular drugs, smokers. Exclusion: reported habitual alcohol intake of more than 30 g/day or drug use. |
Baroreflex function |
| Chang et al. [53] | Before and after 3 months of CPAP therapy. CPAP compliance was defined as days of CPAP use (for at least 4 h/d) and was expressed as a percentage of the total study period = 78.9 (SD 14.5). |
N = 13 (100% male), 50 (SD 7) years. | Baseline AHI: 60.3 (SD 21.2). CPAP treated AHI: 4 (SD 2). |
Inclusion:middle-aged untreated men with severe OSA. Exclusion: clinical diagnosis or history of respiratory disease, cerebrovascular or coronary heart disease, endocrinologic conditions (e.g. neurodegenerative diseases, epilepsy, head injury), psychiatric disorders (e.g. recurrent depression, psychotic disorders, substance-related disorders), or current intake of psychotropic medications. |
HRV |
| Chrysostomakis et al. [54] | Before and after 2 months of CPAP therapy. CPAP compliance not stated. |
N = 26 (69% male), 49 (SD 8) years. | Baseline AHI: 58 (SD 24). CPAP treated AHI: not stated. |
Inclusion:documented moderate to severe sleep apnea. Exclusion: hypertension, diabetes mellitus, sinus node disease or atrioventricular conduction abnormalities, indications of coronary artery disease, dilated or hypertrophic cardiomyopathy, valvular heart disease, respiratory failure and lung disease that might have led to structural or functional pulmonary dysfunction, patients currently on medication with cardioactive drugs (affecting the heart rate), hypnotics or drugs affecting sleep. |
HRV |
| Coruzzi et al. [10] | Before and after 3 months of oral device treatment. Oral device treatment compliance not stated. |
N = 10 (60% male), 48 (SD 10) years | Baseline AHI: 18 (SD 1). CPAP treated AHI: 4 (SD 1). |
Inclusion: normotensive, free of any other known disease, receiving no medications, nonsmokers at the time of the study and during the previous 6 months. All subjects were used to drinking no more than 2 cups of expresso coffee per day, this being the case both at baseline and during treatment. Exclusion:participants with no evidence of significant occlusion defects. |
HRV |
| Huang et al. [12] | Before and after uvulo-palato-pharyngoplasty or Z-palatopharyngoplasty. | N = 40 (% sex not stated), age not stated. | Before surgery AHI: 35 [IQR 17, 59]. After surgery AHI: 15 [4, 43]. |
Inclusion: patients with OSA, surgical procedure were determined upon the discretion of the treating sleep surgeon based on the severity of OSA with PSA and conditions of upper airway abnormality as examined by flexible fibroscopy. Exclusion: patients with moderate-to-sever heart failure, any type of arrhythmia, pacemaker implantation, underlying medical diseases known to affect autonomic system, such as diabetes mellitus and chronic renal failure; had neoplastic disorders; had stroke history, critical carotid stenosis requiring carotid end-arterectomy or stenting, myocardial infarction, or coronary artery diseases status post percutaneous trans-luminal coronary angioplasty or bypass surgery; and had central or peripheral disorders known to affect autonomic system, such as Parkinson’s disease, diffuse Lewy-body disease, multiple system atrophy, and pure autonomic failure. |
HRV Baroreflex function |
| Isobe et al. [55] | Before and after average 123 days of nCPAP therapy. nCPAP mounting time 5 (SD 2) h/day. |
N = 76 (83% Male), 62 (IQR 25–88) years. | Baseline AHI: 45 [7–141]. CPAP treated: 3 [0.3–23]. |
Inclusion:indicated for subjects with moderate to severe OSAS, defined as an AHI ≥ 20 (events/hour) with strong subjective symptoms, such as excessive daytime sleepiness, and morningheadache. Exclusion: patients with > 5 central sleep apnea events per hour who could not undergo nCPAP. |
MSNA |
| Ito et al. [19] | Before and after nCPAP Before and after uvulopalatopharyngoplasty. |
N = 5 (nCPAP), n = 2 (uvulopalatopharyngoplasty), (100% male), 46 [range 32–59] years. | Baseline AHI: 42 [range 31–77] Treated AHI: 2 [range 1–4]. |
Inclusion: newly diagnosed OSA, never been treated for OSA, median BMI 32.2 kg/m2 start of the study. History of hypertension (n = 5), none presented clinical or electrocardiographical evidence of coronary artery disease, left ventricular hypertrophy, or ST-T wave abnormality; none suffered from congestive heart failure or diabetes mellitus, and none received any medication including b-blocker, an antiarrhythmic drugs, or digitalis. | Baroreflex function HRV |
| Jurysta et al. [56] | Before and after 4 years of nCPAP therapy. Compliance 6 ± 1 h/night. |
N = 8 (100% Male), 46 (SD 7) years. | Baseline AHI: 64 (SD 23) nCPAP treated AHI: 6 (SD 4). |
Inclusion: patients suffering from severe SAHS and treated by nCPAP during at least one year were selected retrospectively, provided they did not develop any cardiovascular disease or mental or neurological disorder. Exclusion: other sleep disorders such as parasomnia. |
HRV |
| Kuramoto et al. [57] | Before and after 3 months nCPAP therapy. Treatment compliance not stated. |
N = 38 (87% male), 52 (SD 13) years | Baseline AHI: 57 (SD 21). nCPAP treated AHI: not stated |
Inclusion: patients diagnosed with OSA by polysomnography. Exclusion: Individuals with cerebral infarction, myocardial infarction within 3 months, coronary bypass graft, aortic diseases and atrial fibrillation. |
HRV |
| Limphanudom et al. [58] | Before and after 1, 3, and 6 months CPAP therapy. Compliance 5 h/night. |
N = 10, (100% male), 45 (SD 5) years. | Baseline AHI: 61 (SD 32). CPAP treated AHI not stated. |
Inclusion: newly diagnosed moderate to severe OSA. None had any underlying disease that was causing autonomic dysfunction and cardiac arrhythmia, no evidence of chronic lung disease, or any beta-blocker or anti-arrhymic drugs. | HRV |
| Nakamura et al. [59] | Before and after 1 month of nCPAP therapy. | N = 48 (94% Male), 46 (SD 11) years. | Before treatment AHI: 52 (SD 19) After 1 month after of CPAP treatment AHI: not stated |
Inclusion: consecutive OSAHS with an AHI ≥ 20 who had undergone nCPAP therapy. None of the participants had cardiac disease or arrhythmia, 16 patients had hypertension and were on various antihypertensive agents for > 1 month before the start of this study and throughout the study. None of the patients had received antiarrhythmic agents. Exclusion:not stated. |
I-metaiodobenzyl-guanidine (MIBG) imaging |
| Narkiewicz et al. [60] | Before and after 1month, 6 months and 1 year of CPAP therapy. Compliance with prescribed CPAP treatment was based on self-reported estimated use, expressed as average time with CPAP in relation to total time spent in bed. All treated patients reproted > 75% compliance with CPAP. |
N = 11 (91% Male),46 (SD 8) years. | Baseline AHI:27 (SD 6). |
Inclusion: normotensive, free of any other known diseases, receiving no medication, no central sleep apnea. Exclusion:not stated. |
MSNA |
| Nelesen et al. [13] | Randomized control trial comparing 1 night and 1 week of CPAP treatment with placebo (ineffective level of CPAP). CPAP usage 6 (SEM 0.2) h/night. Placebo usage 6 (SEM 0.2) h/night. |
CPAP: N = 23 (74% Male), 47 (SEM 2) years. Placebo: N = 18 (89% Male), 50 (SEM 2) years. |
CPAP RDI 56 (SEM 5). Placebo RDI 39 (SEM 5). |
||
| Noda et al. [15] | Randomized control trial comparing 3 months of CPAP treatment with no treatment (between subjects). | CPAP N = 14 (100% Male). Non-CPAP N = 19 (100% Male). *Average age of both groups 53 (SD 10) years. Average in each group not provided. |
CPAP: Baseline AHI 53 (SD 12). During CPAP AHI 9 (SD 4). Non-CPAP AHI data not provided. *No differences in baseline AHI were seen between groups. Average AHI values not provided. |
Inclusion:Male patients with OSAS, aged 28 to 71 years. Exclusion:diabetes mellitus, chronic obstructive lung disease, coronary or valvular heart disease, congestive heart failure, renal failure, or endocrine dysfunction, antihypertensive agents at the time of enrollment. |
Baroreflex function Catecholamines |
| Shiomi et al. [11] | Before and after mean 3.3 ± 1.3 months of mandibular advancement therapy. Treatment compliance not stated. |
N = 12 (83% Male), 53 (SD 11) years. | Baseline RDI 30 (SD 17). After mandibular advancement RDI 9 (SD 10). |
Inclusion: normal spirometry and arterial blood gases, normal Valsalva ratios, sufficiently healthy teeth to anchor the dental appliances. Exclusion:evidence of autonomicdysfunction or neuropathy, clinical presence of neurological disease, or lung disease. |
HRV |
| Somers et al. [61] | Before and during 2.1 ± 0.5 h of CPAP treatment. | N = 4 (100% Male), 44 (SD 12) years. | Baseline AHI 65 (SD 9) during CPAP therapy AHI no stated. | Inclusion:hypertension. Other inclusion exclusion criteria not stated. | MSNA |
| Tamisier et al. [62] | Before and after 6 months of CPAP therapy. Average compliance 4.5 h/night. |
N = 26 (% gender not stated), 24–76 (range) years. | Baseline AHI 34 (SD 20). Post CPAP AHI 5 (SD 5). |
Inclusion: 24–76 year olds reporting to a sleep clinic with the complaint of snoring and or sleepiness and confirmation of sleep apnea on polysomnography. No other comorbidities. |
MSNA |
| Yamaguchi et al. [63] | Before and after CPAP use. *Compliance not stated. |
N = 28 (93% Male), 62 (SD 10) years. | Baseline AHI 45 (SD 23). Post CPAP AHI 2 (SD 2). |
Inclusion: no comorbidities, malignancy in any organ, sever hypertension, severe diabetes mellitus, conspicuous heat failure, heart or cerebral attack, renal failure, or impaired cognatic function. Exclusion: taking agonists, b antagonists, or anticholinergic agents, as well as those with atrial fibrillation or artificial cardiac rhythm generated by a pacemaker, were excluded from the analysis. |
HRV |
| Ziegler et al. [14] | Randomizedplacebo control trial comparing before, 2 days and 10 days of CPAP or Placebo (CPAP at ineffective pressure) treatment. *Compliance not stated. |
CPAP: N = 20 (70%Male), 48 (SD 1) years. Placebo CPAP: N = 18 (89% Male), 50 (SD 2). |
CPAP RDI 54 (SD 5). Placebo RDI 39 (SD 5). |
Inclusion: no previous CPAP treatment, between 35 and 65 years, from 100 to 170% of ideal body weight. Exclusion: major medical disorder other than hypertension and sleep apnea. |
Catecholamines |
| Marrone et al. [23] | Before and during CPAP therapy. | N = 10 (90% Male), 49 (SE 4) years. | Without CPAP AHI 75 (SE 5). With CPAP AHI 10 (SE 2). |
Inclusion: affected by OSAS, n = 1 mildly hypertensive participant, none receiving antihypertensive treatment. Exclusion: not stated. |
Catecholamines |
| Dal-Fabbro et al. [17] | Randomized cross over trial comparing before and after 1 month of placebo oral appliance (POA), mandibular advancement device (MAD), and CPAP therapy. | N = 23 (83% Male), 47 (SD 9) years. | Baseline AHI 42 (SD 5). With POA AHI 49 (SD 6). With MAD AHI 27 (SD 5). With CPAP AHI 3 (SD 0.4). |
Inclusion: moderate to severe OSA (AHI ≥ 20), either gender, BMI under 35 kg/m2, 25–65 years of age, dentition in good condition, and a minimum mandibular protrusion of 7 mm. Exclusion: periodontal disease, severe temporomandibular disorders, other sleep disorders, disturbances that interfere in CPAP use, alcohol or drug abuse, previous OSA treatment. |
HRV |
Numbers refer to the number of participants with OSA (not the whole sample being studied in each study). AHI = apnea-hypopnea index. AI = apnea index. CPAP = continuous positive airway pressure. PSG = polysomnography. SD = standard deviation. SEM = standard error of the mean.