Review Article

Nasal Expiratory Positive Airway Pressure Devices (Provent) for OSA: A Systematic Review and Meta-Analysis

Table 2

General characteristics of included studies.

Study quality assessment
Author, year, countryInclusion criteriaExclusion criteriaOutcomes analyzed12345678

Colrain et al., 2008 [12]
USA
(i) 18 years & up
(ii) People who snore or gasp or with apnea reported by their bed partners: selected from community following a telephone screen
(iii) Clinic patients following PSG
BMI >35 Kg/m2, PAP users, URI symptoms, severe nasal allergies, sinusitis, nasal airflow restriction reported by patients, h/o nose surgery or trauma, insomnia or narcolepsy, or PLMD patients, serious medical problems including respiratory failure, heart failure, stroke, cancer, and MI. Females who are pregnant or planning to be pregnantAHI, ODI, min SPO2, %TST SPO2 > 90, %TST snoring, questions related to comfort, ease of breathing via nose, comparison to PAP if patients previously used PAP, and sleep architectures including sleep stages on PSGYesYesYesYesYesNoYesYes

Rosenthal et al., 2009 [16]
USA
Adults with snoring or witnessed apnea or those who are diagnosed with OSAPrior PAP use, severe illness including cancer, CHF, COPD, and other coexistent sleep disorders, and sinusitis or severe nasal allergies or nasal blockageAHI, ODI, PSQI, ESS, and sleep architectures including sleep stages on PSGYesYesYesYesYesNoYesYes

Berry et al., 2011 [18]
USA
Newly diagnosed or untreated OSA patient with prestudy AHI ≥ 10 and age ≥ 18 yearsH/o upper airway surgery, nasal obstruction or chronic nasal decongestant use, severe nocturnal oxygen desaturations, prior PAP or oral device use, sedative or neuromedications which affect alertness, serious or uncontrolled chronic illnesses, and other comorbid sleep disordersAHI, ODI, SPO2 < 90%, ESS, and sleep architectures including sleep stages, effect of position on sleep stages, REM and non-REM AHI, and arousal index on PSGYesYesYesYesYesYesYesYes

Kryger et al., 2011 [19]
USA
Patients with ≥ 50% reduction in AHI or AHI of < 10 on 3-month n-EPAP on PSG or 1-week device off PSG
n-EPAP use of ≥ 4 h/night and ≥ 5 nights/week on average 3-month trial of n-EPAP versus sham study
Same criteria as for original n-EPAP versus sham study. H/o upper airway surgery, nasal obstruction or chronic nasal decongestant use, severe nocturnal oxygen desaturations, prior PAP or oral device use, sedative or neuromedications which affect alertness, serious or uncontrolled chronic illnesses, and other comorbid sleep disordersAHI, ODI, SPO2 < 90%, ESS, snoring, and sleep architectures including sleep stages, effect of position on sleep stages, REM and non-REM AHI, and arousal index on PSGYesYesYesYesYesNoYesYes

Patel et al., 2011 [13]
USA
OSA patients with AHI with 4% desaturation > 5/hr Patients with significant nasal obstruction, central apnea, CHF, neuromuscular disease, hypoventilation, elevated serum bicarbonate or arterial PCO2, and unexplained desaturations on baseline PSG, EtCO2 in supine and lateral positions in sleep and wakefulness during PSG, awake lung volumes in sitting, supine, and lateral positions including FEV1, FVC, FRC, ERV, TLC, and FEV1/FVC, and sleep architectures including sleep stages, effect of positions on sleep, REM and non-REM AHI, and arousal index NoYesYesYesYesNoYesYes

Walsh et al., 2011 [17]
USA
18-year-olds with OSA symptoms who refused or are nonadherent to CPAP with less than 3 hours of nightly use & AHI on baseline of >15 or >10 with symptoms of daytime sleepiness, mood issues, or hypertension or cognitive impairmentNasal blockage or allergies or sinusitis, chronic use of nasal decongestants or nasal lesions, comorbid sleep, other sleep disorders, cardiorespiratory diseases, psychiatric disorders, pregnancy, and large caffeine consumptionAHI, ODI, ESS, FOSQ, and sleep architecture variables including sleep stages, percent of oxygen saturations, and arousal indicesNoYesYesYesYesNoYesYes

Rossi et al., 2013 [14]
UK, Switzerland
Diagnosed and treated for OSA with CPAP for >12 months of ≥ 4 hours of nightly use prior to this trial in ages between 20 and 75 years, ODI of >10/h on baseline PSG or >10/h on nocturnal pulse oximetry test prior to enrolling for this trial. This test was performed on last night of 4-day CPAP off periodH/o CAD, PAD, uncontrolled or severe HTN, ventilator failure or Cheyne-Stokes breathing, sleep related accidents, comorbid sleep disorder, or commercial driversAHI, ODI, ESS, BP, and ODI from home oximetryYesYesYesYesYesYesYesYes

Friedman et al., 2015 [15]
USA
Age >18, diagnosis of OSA in previous 12 mo., failed CPAPNo stringent exclusion criteriaAHI, ODI, SPO2, snoring by VAS, ESS, and SAQLINoYesYesYesYesNoYesYes

Quality assessment of the included studies checklist from questions from National Institute for Health and Clinical Excellence (NICE): 1–8: (1) Case series collected in more than one center? (2) Is the hypothesis/aim/objective of the study clearly described? (3) Are the inclusion and exclusion criteria clearly reported? (4) Is there a clear definition of the outcomes reported? (5) Were data collected prospectively? (6) Is there an explicit statement that patients were recruited consecutively? (7) Are the main findings of the study clearly described? (8) Are outcomes stratified?
PLMD: periodic limb movement disorder; MI: myocardial infarction or angina; PAP: positive airway pressure; B/W: between; ODI: oxygen desaturation index; min SPO2: minimum oxygen saturation; TST SPO2: total sleep time with oxygen saturation; PSQI: Pittsburgh Sleep Quality Index; ESS: Epworth Sleepiness Scale; COPD: chronic obstructive pulmonary disease; CHF: congestive heart failure; REM: rapid eye movement sleep; non-REM: nonrapid eye movement sleep; FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity; FRC: functional residual capacity; ERV: expiratory reserve volume; TLC: total lung capacity; : critical closing pressure; EtCO2: end tidal CO2; n-EPAP: nasal EPAP (Provent); FOSQ: Functional Outcomes of Sleep Questionnaire; CAD: coronary artery disease; PAD: peripheral arterial disease; HTN: hypertension; BP: blood pressure; SAQLI: sleep apnea quality of life index; VAS: visual analog scale for snoring measurement.