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At least 19 recordsLinked to original sources
PubMed2026

Performance of AI-Based Screening Tools for Obstructive Sleep Apnea Across Apnea-Hypopnea Index Thresholds: Systematic Review and Meta-Analysis.

BACKGROUND: Obstructive sleep apnea (OSA) is highly prevalent but remains substantially underdiagnosed. Polysomnography (PSG) is the reference standard, but its cost and limited availability constrain large-scale case identification. AI-based screening tools may support risk stratification and referral prioritization, but their diagnostic accuracy across apnea-hypopnea index (AHI) thresholds remains uncertain. OBJECTIVE: This review aimed to systematically evaluate the diagnostic accuracy of AI-based OSA screening tools at AHI thresholds of ≥5, ≥15, and ≥30 events/hour, with emphasis on models using non-PSG-derived inputs. METHODS: PubMed, Embase, Scopus, and Web of Science were searched for studies published from January 1, 2016, to May 3, 2026. Eligible studies included adults evaluated for suspected OSA or recruited from population-based cohorts, assessed AI-based models intended or interpretable for OSA screening, risk prediction, or screening-oriented severity classification, used PSG as the reference standard, and reported sufficient data to construct or reconstruct 2×2 contingency tables. Diagnostic accuracy was synthesized separately by AHI threshold and input source using bivariate random-effects models, with 95% CIs and prediction intervals (PIs). Risk of bias and certainty of evidence were assessed using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) and GRADE (Grading of Recommendations Assessment, Development, and Evaluation), respectively. RESULTS: A total of 60 studies were included, of which 47 contributed data to the meta-analysis. At AHI thresholds of ≥5, ≥15, and ≥30 events/hour, pooled sensitivities were 0.94 (95% CI 0.92-0.96; 95% PI 0.71-0.99), 0.87 (95% CI 0.84-0.89; 95% PI 0.66-0.96), and 0.83 (95% CI 0.79-0.87; 95% PI 0.61-0.94), respectively; the corresponding specificities were 0.77 (95% CI 0.69-0.84; 95% PI 0.30-0.96), 0.81 (95% CI 0.75-0.85; 95% PI 0.39-0.96), and 0.91 (95% CI 0.87-0.94; 95% PI 0.55-0.99), respectively. The corresponding areas under the summary receiver operating characteristic curves were 0.943, 0.907, and 0.920. For non-PSG-derived tools, sensitivities were 0.92, 0.85, and 0.81, and specificities were 0.70, 0.74, and 0.85 at the 3 thresholds, respectively. For PSG-derived models, sensitivities were 0.96, 0.90, and 0.85, and specificities were 0.82, 0.88, and 0.96, respectively. Exploratory subgroup analyses suggested performance variation across selected study and model characteristics, including region, algorithmic framework, data source, and validation method. CONCLUSIONS: AI-based tools showed generally favorable screening performance for OSA across clinically relevant AHI thresholds, although wide PIs suggest variable performance across future comparable populations and settings. By synthesizing diagnostic accuracy across 3 AHI thresholds and distinguishing non-PSG-derived from PSG-derived models, this review extends previous broad or modality-specific reviews and offers a clinically interpretable, pathway-specific basis for linking model performance to intended use. The findings may clarify potential roles for non-PSG-derived tools in front-end screening and referral prioritization and for PSG-derived models in reduced-channel assessment and sleep-laboratory workflow support. Given substantial heterogeneity, limited external validation, and low or very low certainty of evidence, prospective validation is needed before routine implementation.

Humans↗
PubMed1977

The sleep state characteristics of apnea during infancy.

The sleep state characteristics of infant sleep apnea were studied in 36 twins examined by polygraphy at 40, 44, and 52 weeks after conception. The definition of sleep apnea is dependent upon the length of apnea, sleep state, and post-conceptional age. None of the infants had apnea longer than 20 seconds and apnea of 10 seconds or longer was uncommon. The attack rates for apneas 2 to 4.9 seconds long were highest in REM and lowest in qliet sleep. The attack rates for apneas 5 to 9.9 seconds long were equal in REM and indeterminate and lowest in quiet sleep. The percentage of infants with apnea of 10 seconds or longer at 40 weeks was highest in REM (27%) and indeterminate sleep (42%) and lowest in quiet sleep (12%). At 52 weeks, apnea 10 seconds or longer during REM decreased to 0%. The effect of maturation on apnea varies with sleep state. Over the period from 40 to 52 weeks, quiet sleep apnea was unchanged and indeterminate sleep apnea decreased only between 40 and 44 weeks. Although REM apnea 2 to 4.9 seconds long was unchanged, REM apnea 5 to 9.9 seconds long decreased between 40 and 44 weeks, and REM apnea of 10 seconds or longer decreased from 27% at 40 weeks to 0% at 52 weeks. This suggests that semi-independent apnea turn-on and turn-off mechanism operate during REM sleep. A correlation between brief apneas and the longer apneas was seen only during REM sleep. For all sleep states, there was no correlation between the levels of apnea of 5 seconds or longer at 40, 44, and 52 weeks.

Aging↗
PubMed1977

Polygraphic studies of normal infants during the first six months of life: III. Incidence of apnea and periodic breathing.

The incidence of apnea and periodic breathing was studied in full-term infants between birth and 6 months of age. Apnea was defined as a pause equal to or exceeding six seconds, periodic breathing as two cessations of breathing within a 20-second period, each equal to or longer than three seconds but less than six seconds. Sleep and cardiopulmonary variables were monitored. Apnea was common in the normal full-term infant. The incidence of apnea was highest in the newborn period and apneas exceeding 15 seconds were limited to this age. A reduction in apnea incidence occurred between birth and 3 months of age; thereafter, the incidence remained unchanged. The majority of apneas occurred during active sleep (AS). Few minutes were classified as indeterminate; the number of apneas during these minutes was comparable to those during AS. The incidence of apneas during quiet sleep was low. Periodic breathing remained stable across the ages, occurring primarily in AS. Apnea exceeding 15 seconds in rare in infancy. The tabulation of shorter apnea may be of limited value in identifying infants at risk for abnormal apnea due to extreme variability among infants. The sleep-waking state of the infants must be considered in order to evaluate apnea counts.

Apnea↗
PubMed1979

Sleep apnea in hypoxic and normal kittens.

Frequency and characteristics of apneas were studied in 10-, 20-, and 40-day old kittens during several days of exposure to 21%, 10%, or 7% oxygen atmospheres. Ninety-seven percent of all apneas occurred during sleep or at transitions between sleep and waking states. Hypoxic kittens, compared to controls, had greatly decreased apnea frequency, but other characteristics of apneas did not differ significantly. Apneas in both control and hypoxic kittens were normal, stereotyped events and were not considered to represent pathological processes. Evaluation of events preceding apneas indicated that a majority of apneas followed augmented breaths and/or brief arousals. We suggest that apnea, heart rate changes during apnea, and frequently concurrent transitions in sleep-waking state may be causally related to these pre-apnea events. The results of this study and a parallel study of human infants suggest that below-normal apnea frequency may indicate hypoxemia and may be associated with higher risk for Sudden Infant Death Syndrome.

Age Factors↗
PubMed1977

Prolonged sleep apnea and respiratory instability: a discriminative study.

This report is based on a study of 53 infants, 28 of whom had clinically observed prolonged apnea (greater than or equal to 20 seconds) during sleep whereas the remaining did not. In addition to the clinical observations, each infant was studied in a sleep laboratory during a complete nap, and a continuous recording was made of respiratory activity and rapid eye movements. Measurements were made of all apneic pauses (greater than or equal to 2 seconds) observed in the laboratory and the two groups of infants were compared in terms of the frequency and average duration of apneic pauses, the longest apneic pause, the amount of periodic apnea, and the relative amount of apnea. The infants with prolonged sleep apnea had, during a single nap, more frequent and longer apneic pauses and more periodic apnea. This supports the hypothesis that respiratory instability during sleep and prolonged apnea have a common etiology. By employing a multiple linear regression model and including all laboratory apnea measures in a single analysis, a composite laboratory score was developed to differentiate members of the two groups. It would thus appear that the study of infants during a single nap could assist in the identification of infants at risk for prolonged sleep apnea and provide an indirect method for determining the influence of a number of variables on the occurrence of prolonged sleep apnea. Pediatrics, 59:962-970, 1977, SLEEP, APNEA, RESPIRATORY INSTABILITY.

Apnea↗
PubMed1978

Duration of apnea needed to confirm brain death.

To determine the duration of respiratory arrest needed to attain a PaCO2 level high enough to provide maximal stimulation of respiration, we evaluated changes in PaCO2, PaO2 and apH during periods of apnea lasting as long as 10 minutes in 10 apparently brain-dead subjects. Before apnea, mean PaCO2 was 33 mm Hg. In seven subjects who did not breathe for 10 minutes, the mean rate of rise of PaCO2 was 3.2 mm Hg per minute. PaCO2 at 4 minutes was 50 mm Hg and at 10 minutes was 67 mm Hg. Three subjects breathed, two after less than 2 minutes of apnea, when PaCO2 was 47 and 54 mm Hg, and one after 4.5 minutes, when PaCO2 was 47 mm Hg. These data indicate: (1) that the threshold for respiratory stimulation may approach a PaCO2 of 60 mm Hg in patients with brain damage; (2) that the rate of increase in PaCO2 is such that, even in a normocapnic subject after 3 minutes of apnea, the PaCO2 may not be sufficiently high to stimulate respiration; and (3) if a patient is hypocapnic prior to the onset of apnea, PaCO2 may not reach 60 mm Hg even after 15 minutes. To confirm absolute apnea, then, blood gas monitoring is necessary for verification of normocapnia prior to the beginning of apnea. In the absence of blood gas determinations, no fixed period of apnea, sufficient in all cases to establish absolute apnea, can be ascertained.

Adult↗
PubMed2026

Obstructive sleep apnea and long-term risk of site-specific cancers: A population-based cohort study.

BACKGROUND: Obstructive sleep apnea is common, but its long-term association with site-specific cancers remains unclear. In this study, we examined 15-year risks of site-specific cancers in people with obstructive sleep apnea compared with the general population and to people with overweight or obesity. METHODS: We conducted a nationwide population-based cohort study using Danish registries, 1995-2021. People diagnosed with obstructive sleep apnea were compared with the general population and to people with overweight or obesity. Adjusted (weighted) 15-year risks, risk differences, and risk ratios (RRs) were estimated using the Aalen-Johansen estimator. Confounding was addressed using standardized morbidity ratio weighting. RESULTS: The study included 114,264 people with obstructive sleep apnea, 115,497 members of the general population, and 113,034 with overweight or obesity. After weighting, the distributions of sex (74% male), age (median 53 years), and comorbidities were comparable across the three cohorts. Obstructive sleep apnea was associated with an increased risk of cancers of the brain (adjusted 15-year risk: 5.78 vs. 3.61 per 1,000 persons; aRR 1.60 [95% CI 1.43-1.78]) and spinal cord (1.65 vs. 1.17 per 1,000 persons; aRR 1.41 [95% CI 1.16-1.72]) compared with the general population. Associations persisted when the obstructive sleep apnea cohort was compared with those with overweight or obesity. No associations were observed for other site-specific cancers. CONCLUSION: Obstructive sleep apnea was associated with an increased risk of brain and spinal cord cancers. These findings highlight the importance of effective prevention of obstructive sleep apnea and the need for further research on treatment.

Cohort Study↗
PubMed1976

[Sleep and respiration in the syndrome "apnea during sleep" in the child].

A sleep apnea syndrome has been diagnosed in eight children (age range 5-14). Before undertaking therapeutic trials, sleep and respiration were extensively studied. Sleep and respiration were again analyzed 3 months after tonsillectomy and adenoidectomy (6 cases) or tracheostomy with insertion of valve (2 cases). Sleep induced apneic apisodes in these children who had normal respiration during wakefulness. Three types of apnea (central, upper airway, and mixed) were recorded in each case. The minimum number of apneas recorded during a single night was 75; the maximum was 816. Polygraphic monitoring demonstrated greatly disturbed sleep. Sleep changes were quantitative as well as qualitative. REM sleep percent was decreased, but stages 3 and 4 NREM sleep were also impaired. A relationship between stages 3-4 NREM sleep and respiration was noted: stages 3-4 sleep disappeared when apneic episodes were numerous; no apnea was recorded during stage 4 sleep. Follow-up nocturnal recordings of two tracheostomized children with valve open, then closed, confirmed this "stage 4/no apnea" relationship. Apneas were also noted to induce marked sinus arrhythmia during sleep.

Adolescent↗
PubMed1975

Oxygen consumption and conservation during apnea in the anesthetized dog.

Apnea was initiated by clamping off the tracheal tube in 6 anesthetized dogs. Bradycardia, reduction in cardiac output and peripheral vasoconstriction developed gradually throughout the entire apneic period. O2 consumption during apnea was measured by monitoring the rate of O2 removal from the lung (VLO2), from the arterial blood (Va02), and from the venous blood (VV02). Total 02 consumption (VT02) was calculated by summing (VL02--Va02), VaQ2 and VV02-VL02, estimated by the product of arteriovenous O2 content difference and cardiac output, decreased continuously during apnea. At the end of 80 sec the rate of O2 removal from the lung was one-fourth of the pre-apneic rate, 5.29 +/- 0.51 ml-min-1kg-1. Oxygen disappearance form the blood was estimated by measuring arterial and venous O2 content at 20-sec intervals and by assuming a constant blood volume throughout the apneic period of 86 ml/kg, 25% of which is in the arterial tree and 75% of which is in the venous compartment. During the last 20 sec of an 80-sec apnea, VV02 represented 69% of VT02. The result indicated that VT02 during apnea was not significantly different from that of pre-apneic values. It is concluded from the present study that an oxygen conservation mechanism if existent, was not operative during an 80-sec apnea in the anesthetized dog.

Animals↗
PubMed1978

Physiologic changes induced by theophylline in the treatment of apnea in preterm infants.

Ten preterm infants (birth weight 0.970 to 2.495 kg) with apnea due to periodic breathing (apneic interval = 5 to 10 seconds) or with "serious apnea" (greater than or equal to 20 seconds) were studied before and after the administration of theophylline. We determined the incidence of apnea, respiratory minute volume, alveolar gases, arterial gases and pH, "specific" compliance, functional residual capacity, and work of breathing. Theophylline decreased the incidence of apnea (P less than .05), increased respiratory minute volume (P less than 0.001), decreased (PACO2 (and PaCO2 P less than 0.001), increased the slope of the CO2 response curve (P less than 0.02) with a significant shift to the left (P less than 0.02). These findings suggest that the decreased incidence of apnea after theophylline is associated with an increase in alveolar ventilation and increased sensitivity to CO2 with a pronounced shift of the CO2 response curve to the left. These data are consistent with the idea that apnea is a reflection of a depressed respiratory system.

Apnea↗
PubMed1978

Prolonged apnea in infant monkeys resulting from stimulation of superior laryngeal nerve.

We measured characteristics of apnea resulting from electrical stimulation of the superior laryngeal nerve (SLN) in 28 anesthetized infant monkeys ranging from a gestational age of 141 days to 49 days postterm and in four adult monkeys. Progressive reduction in ventilation accompanied weak suprathreshold SLN stimulation. Poststimulus apnea followed stronger stimulation. Apnea duration was directly proportional to stimulus duration, provided that stimulus intensity was at least 1.5 X threshold. Poststimulus apnea periods were briefer in older infants and did not occur in adults. Pao2 measurements in four animals showed that lower values were associated with the longer poststimulus apnea episodes. Upper airway resistance measurements obtained from a subglottal cannula revealed that glottal closure was transiently associated with the onset of SLN stimulation, but the degree of closure diminished during the course of stimulation and was not present during the subsequent period of apnea. The parameters of SLN stimulation determine specific changes in cardiovascular functions independently of their respiratory effects. The results suggest that a brief afferent input from the SLN may have prolonged effects on respiratory regulation in infants. These persisting effects may be an important consideration in sudden infant death syndrome mechanisms.

Airway Resistance↗
PubMed1975

Hypoxic apnea and gasping.

We have tested the hypothesis that severe lypoxia causes apnea, regardless of the arterial CO2 and pH, and that extreme hypoxia causes gasping. Acute experiments with airway occlusion and with low inspired oxygen (FIo2) were performed on anesthetized adult dogs and monkeys. Arterial oxygen saturation was recorded continuously with fiberoptic oximetry, and Pco2 by an electrode catheter. In addition, blood samples were obtained for Po2, Pco2, and pH. Apnea was induced regularly when the Pao2 fell below 10 torr, whether the Paco2 was high with asphyxia (63 torr) or low (26 torr) with low FIo2. Similarly, the Pao2 at apnea was the same whether the pH was 7.17 with asphyxic hypoxia or 7.46 with hypoxic hypoxia. Gasping occurred at even lower Pao2 (below 5 torr) after 1 or 2 min of apnea. Gasping promptly restored the Pao2 to levels of moderate hypoxia (over 30 torr) which permitted resumption of regular respiration, with gradual elimination of the gasping. Fetal monkeys at term were studied in a similar manner from the moment of cord clamping. Their blood gases with apnea were quite similar to adult values in the narrow range of Pao2 and the wide range of Paco2 and pH. In the fetus, gasping was less immediately effective in improving arterial oxygen, but more persistent than in the adult. Regular respirations would not develop in the absence of oxygen in either the fetus or adult animal.

Acid-Base Equilibrium↗
PubMed1979

Sleep apnea in normal kittens.

Apneic episodes in normal 10-, 20-, and 40-day-old kittens were assessed with polygraphic recordings. End expiratory apneas, usually preceded by somatic activity and/or augmented breaths, with durations less than 10 sec were observed in quiet sleep, active sleep, and transitions between states in all age groups. The highest apnea density was found at state transitions. Heart rate decelerations occurred before, during, and following apneas, but decelerations were not related to apnea duration. Combined central and obstructive components were associated with 9% of apneas in normal kittens.

Age Factors↗
PubMed1979

Neonatal apnea: underlying disorders.

Data from a prospective study of 50,826 neonates were used to determine the frequency and significance of disorders related to apnea in newborns. Such apnea proved to be a significant prognosticator for neonatal death. Fifty-eight percent of preterm neonates with multiple apneic episodes and 18% with a single episode died, whereas only 6% of those without recorded apnea died. The rates were 44%, 5%, and 1% for full-term infants. Amniotic fluid infection was the underlying disorder in 35% of the preterm and 25% of the term neonates who had multiple episodes of apnea. A third of the preterm and 25% of the term infants who had such apneic episodes had antecedent hypoxia-related disorders, i.e., abruptio placentae, erythromblastosis fetalis, placenta previa, large placental infarcts, and umbilical cord compression. Among the apneic neonates, those who were infected were twice as apt to die as were those who had hypoxia-related disorders. Hypoplasia of the lungs and easily recognized central nervous system malformations were responsible for most of the apnea-related deaths associated with congenital malformations.

Amniotic Fluid↗
PubMed1979

Endoscopic findings in sleep apnea syndrome.

Sleep apnea syndrome is a constellation of symptoms resulting from recurrent episodes of apnea during sleep. Often the upper airway becomes obstructed during slumber in this disorder. Symptoms relate to sleep deprivation and include morning headaches, daytime somnolence, personality changes with deteriorating intellectual capacity, nocturnal enuresis, and sexual dysfunction. Diagnosis is assisted by polysomnographic recordings. Therapy is directed at the cause of obstruction when one can be found, weight loss in massively obese patients, tracheostomy in the symptomatic patient. Four patients with documented sleep apnea syndrome are discussed. One patient, a thin adolescent female underwent adenoidectomy without improvement. Two massively obese adult males required tracheostomy with marked amelioration of symptoms. One additional adult male was found to have sleep apnea due to severe, acquired micrognathia; he was significantly improved by tracheostomy. All three adult patients were found by endoscopic visualization to have marked pharyngeal soft tissue collapse with inspiration during apneic episodes. Possible causes of pharyngeal collapse are discussed.

Adolescent↗
PubMed1977

Efficacy of caffeine in treatment of apnea in the low-birth-weight infant.

The efficacy of caffeine citrate in the management of apnea in the newborn infant was evaluated. Caffeine citrate was given to 18 preterm neonates with recurrent apneic spells. Mean (+/- SE) birth weight and gestational age were 1,065.0 +/- 71.9 gm and 27.5 +/- 0.6 weeks, respectively. Mean age at onset of apnea and at initiation of caffeine treatment was 6.5 +/- 3.7 days and 18.2 +/- 4.9 days, respectively. Caffeine citrate was administered with a loading dose of 20 mg/kg intravenously followed within two to three days by 5 to 10 mg/kg once or twice daily. All infants except one showed a significant decrease in the frequency of apneic episodes associated with caffeine therapy. Mean frequencies of apneic spells were 13.6 +/- 2.5 and 2.1 +/- 0.6 apnea per day before and after initiation of caffeine treatment, respectively. Respiratory rate was increased, and blood [h]+ion concentration and Pco2 were decreased. The data suggest that caffeine is an effective pharmacologic respirogenic agent in the preterm infant with apnea.

Apnea↗
PubMed1979

Gastroesophageal reflux causing respiratory distress and apnea in newborn infants.

Respiratory distress, apnea, and chronic pulmonary disease since birth were identified in 14 infants who also had symptomatic gastroesophageal reflux. Birth weights varied from 760 to 4,540 gm. All infants had radiographic changes similar to those in bronchopulmonary dysplasia. Cessation of apnea and improvement of pulmonary disease occurred only after medical (8) or surgical (6) control of gastroesophageal reflux. Simultaneous tracings of esophageal pH, heart rate, impedance pneumography, and nasal air flow in five infants demonstrated that reflux preceded apnea. Apnea could be induced by instillation of dilute acid, but not water or formula, into the esophagus. Prolonged monitoring of esophageal pH more than two hours after feeding in 14 other infants less than 6 weeks of age (birth weight 780 to 3,350 gm) without a history of recent vomiting indicated that reflux was not greater than in normal older children.

Apnea↗