Supine Sleep Research Articles

Arousal from sleep pathways are affected by the prone sleeping position and preterm birth: Preterm birth, prone sleeping and arousal from sleep

ObjectivesPreterm infants exhibit depressed arousability from sleep when compared with term infants. As the final cortical element of the arousal process may be the most critical for survival, we hypothesized that the increased vulnerability of preterm infants to the Sudden Infant Death Syndrome (SIDS) could be explained by depressed cortical arousal (CA) responses. We evaluated the effects of preterm birth on stimulus-induced arousal processes in both the prone and supine sleeping positions. Study design10 healthy preterm infants were studied with daytime polysomnography, in both supine and prone sleeping positions, at 36weeks gestational age, 2–4weeks, 2–3months and 5–6months post-term corrected age. Sub-cortical activations and cortical arousals (CA) were expressed as proportions of total arousal responses. Preterm data were compared with data from 13 healthy term infants studied at the same corrected ages. ResultsIn preterm infants increased CAs were observed in the prone position at all ages studied. Compared to term infants, preterm infants had significantly fewer CAs in QS when prone at 2–3months of age and more CAs when prone at 2–4weeks in AS. There were no differences in either sleep state when infants slept supine. ConclusionsProne sleeping promoted CA responses in healthy preterm infants throughout the first six months of post-term age. We have previously suggested that in term infants enhanced CA represents a critical protection against a potentially harmful situation; we speculate that for preterm-born infants the need for this protection is greater than in term infants.

Polysomnographic effect of nasal surgery on positional and non-positional obstructive sleep apnea/hypopnea patients

Conclusion: The polysomnographic (PSG) effects of nasal surgery on positional obstructive sleep apnea/hypopnea syndrome (OSAHS) patients (PPs) and non-positional OSAHS patients (NPPs) were different. Objective: We aimed to determine the PSG data changes after nasal surgery and evaluate the PSG effect of nasal surgery on PPs and NPPs, respectively. Methods: A total of 79 OSAHS patients with nasal obstruction were recruited. Preoperative rhinomanometry and overnight polysomnography were recorded. Patients were distributed into three groups based on the severity level of the apnea and hypopnea indexes (AHI) (mild, moderate, and severe OSAHS). Three groups were each subdivided into two subgroups (PPs and NPPs). Postoperative data were obtained at least 6 months later. Results: After surgery, although nasal resistance decreased significantly in all patients, the total rate of success and response in treating OSAHS was only 22.7%. Grouped on the basis of the severity level of AHI, the lowest SpO2 increased and AHI, supine AHI, and arousal indexes decreased significantly only in mild OSAHS (p < 0.05). Subdivided according to the presence or absence of positional dependency, the lowest SpO2 increased and supine AHI decreased significantly in both PPs and NPPs with mild OSAHS and in PPs with moderate OSAHS (p < 0.05). AHI significantly increased in PPs with severe OSAHS (p < 0.05). Supine sleep time was relatively prolonged significantly in PPs with moderate and severe OSAHS (p < 0.05).

Association of maternal sleep practices with pre-eclampsia, low birth weight, and stillbirth among Ghanaian women

ObjectiveTo assess sleep practices, and investigate their relationship with maternal and fetal outcomes, among pregnant Ghanaian women. MethodsIn a cross-sectional study conducted at Korle Bu Teaching Hospital, Accra, Ghana, between June and July 2011, postpartum women were interviewed within 48hours of delivery about sleep quality and practices during pregnancy. Interviews were coupled with a systematic review of participants’ medical charts for key outcomes including maternal hypertension, pre-eclampsia, premature delivery, low birth weight, and stillbirth. ResultsMost women reported poor sleep quality during pregnancy. Snoring during pregnancy was independently associated with pre-eclampsia (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.4–8.5; P=0.007). The newborns of women who reported supine sleep during pregnancy were at increased risk of low birth weight (OR, 5.0; 95% CI, 1.2–20.2; P=0.025) and stillbirth (OR, 8.0; 95% CI, 1.5–43.2; P=0.016). Low birth weight was found to mediate the relationship between supine sleep and stillbirth. ConclusionThe present findings in an African population demonstrate that maternal sleep, a modifiable risk factor, has a significant role in pre-eclampsia, low birth weight, and subsequently stillbirth.

Factors Affecting Proportion of Supine Sleep in Patients Referred for Obstructive Sleep Apnea Evaluation: Focusing on Severity of Obstruction during Supine Sleep (P05.016)

Factors Affecting Proportion of Supine Sleep in Patients Referred for Obstructive Sleep Apnea Evaluation: Focusing on Severity of Obstruction during Supine Sleep (P05.016)

Medicine’s future: Helping patients stay healthy at home

<b>Background:</b> Functional residual capacity and vital capacity decrease in the supine position, leading to increase of airways resistance (Denison D. et al. Thorax 1986;418:620-628). During sleep, many patients report increased dyspnoea. Forced oscillation technique (FOT) allows to easily explore lung mechanics in different settings, by measuring conductive (respiratory resistance, Rrs) and elastic (respiratory reactance, Xrs) properties of respiratory system. <b>Aims:</b> Aim of the study was to characterize separately the impact of the supine position and sleep on respiratory mechanics by FOT. <b>Methods:</b> Fourteen consecutive patients hospitalized in a pulmonary ward (12 with airways obstruction and 2 with interstitial disease) were studied by FOT while 1) seated; 2) few minutes after being laid in the supine position and 3) immediately after being waked up during the night. <b>Results:</b> In the obstructed patients only Xrs at 5 Hz worsened when going from seated to supine. Within this group, Xrs further worsened during sleep in 6 subjects. <b>Conclusions:</b> These data suggest that in some patients sleep induces additional worsening of Xrs compared to the supine position per se. FOT can be useful to identify these patients.

The Impact of Body Posture and Sleep Stages on Sleep Apnea Severity in Adults

Determining the presence and severity of obstructive sleep apnea (OSA) is based on apnea and hypopnea event rates per hour of sleep. Making this determination presents a diagnostic challenge, given that summary metrics do not consider certain factors that influence severity, such as body position and the composition of sleep stages. We retrospectively analyzed 300 consecutive diagnostic PSGs performed at our center to determine the impact of body position and sleep stage on sleep apnea severity. The median percent of REM sleep was 16% (reduced compared to a normal value of ~25%). The median percent supine sleep was 65%. Fewer than half of PSGs contained > 10 min in each of the 4 possible combinations of REM/NREM and supine/non-supine. Half of patients had > 2-fold worsening of the apnea-hypopnea index (AHI) in REM sleep, and 60% had > 2-fold worsening of AHI while supine. Adjusting for body position had greater impact on the AHI than adjusting for reduced REM%. Misclassification--specifically underestimation of OSA severity--is attributed more commonly to body position (20% to 40%) than to sleep stage (~10%). Supine-dominance and REM-dominance commonly contribute to AHI underestimation in single-night PSGs. Misclassification of OSA severity can be mitigated in a patient-specific manner by appropriate consideration of these variables. The results have implications for the interpretation of single-night measurements in clinical practice, especially with trends toward home testing devices that may not measure body position or sleep stage.

Infant rolling abilities – the same or different 20 years after the back to sleep campaign?

AimTo compare the order and age of emergence of rolling prone to supine and supine to prone before the introduction of back to sleep guidelines and 20years after their introduction. MethodsThe original normative data for the Alberta Infant Motor Scale (AIMS) were collected just prior to the introduction of back to sleep guidelines in 1992. Currently these norms are being re-evaluated. Data of rolling patterns of infants 36weeks of age or younger from the original sample (n=1114) and the contemporary sample (n=351) were evaluated to compare the sequence of appearance of prone to supine and supine to prone rolls (proportion of infants passing each roll) and the ages of emergence (estimated age when 50% of infants passed each roll). ResultsThe sequence of emergence and estimated age of appearance of both rolling directions were similar between the two time periods. ConclusionThe introduction of the supine sleep position to reduce the prevalence of Sudden Infant Death Syndrome (SIDS) has not altered the timing or sequence of infant rolling abilities. This information is valuable to health care providers involved in the surveillance of infants’ development. Original normative age estimates for these two motor abilities are still appropriate.

Sleep position does not appear to influence the risk of extreme cardiorespiratory events in vulnerable infants

Implications for practice and research: Extreme cardiorespiratory events can be documented during sleep and are more common in immature preterm infants. The supine sleep position does not appear to decrease...

Factors influencing infant sleep position: decisions do not differ by SES in African-American families

ObjectiveTo investigate factors influencing African-American parents’ knowledge, attitudes and practice regarding infant sleep position and determine if these differ by socioeconomic status (SES).MethodsA cross-sectional sample of 412 parents with infants...

Maternal note-taking and infant care: a pilot randomised controlled trial

DesignA pilot randomised controlled trial was conducted with postpartum mothers to assess the feasibility and impact of note-taking during newborn teaching. Controls received standard teaching; the intervention group received pen...

Sudden Infant Death Syndrome: An Update

Sudden Infant Death Syndrome: An Update

New reference values must be established for the Alberta Infant Motor Scales for accurate identification of infants at risk for motor developmental delay in Flanders

The Alberta Infant Motor Scales (AIMS) is a reliable and valid assessment tool to evaluate the motor performance from birth to independent walking. This study aimed to determine whether the Canadian reference values on the AIMS from 1990-1992 are still useful tor Flemish infants, assessed in 2007-2010. Additionally, the association between motor performance and sleep and play positioning will be determined. A total of 270 Flemish infants between 0 and 18 months, recruited by formal day care services, were assessed with the AIMS by four trained physiotherapists. Information about sleep and play positioning was collected by mean of a questionnaire. Flemish infants perform significantly lower on the AIMS compared with the reference values (P < 0.001). Especially, infants from the age groups of 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 and of 15 months showed significantly lower scores. From the information collected by parental questionnaires, the lower motor scores seem to be related to the sleep position, the amount of play time in prone, in supine and in a sitting device. Infants who are exposed often to frequently to prone while awake showed a significant higher motor performance than infants who are exposed less to prone (<6 m: P = 0.002; >6 m: P = 0.013). Infants who are placed often to frequently in a sitting device in the first 6 months of life (P = 0.010) and in supine after 6 months (P = 0.001) performed significantly lower than those who are placed less in it. Flemish infants recruited by formal day care services, show significantly lower motor scores than the Canadian norm population. New reference values should be established for the AIMS for accurate identification of infants at risk. Prevention of sudden infant death syndrome by promoting supine sleep position should go together with promotion of tummy time when awake and avoiding to spent too much time in sitting devices when awake.

Comparison of supine-only and REM-only obstructive sleep apnoea

The effect of body position and sleep state on sleep apnoea have major clinical implications in the management of patients, yet are infrequently reported in the scientific literature. The aim of this study was to compare and contrast the prevalence and severity of supine-only and rapid eye movement (REM)-only obstructive sleep apnoea (OSA) in a population. Prospective cohort analysis of the influence of supine body position and REM sleep on the severity of apnoea in 100 consecutive patients with OSA (apnoea-hypopnoea index [AHI]>5) using attended polysomnography with continuous digital monitoring in an accredited sleep laboratory. Supine-only OSA was defined as a supine:non-supine AHI ratio of >2:1 and non-supine AHI <5 events/h. REM-only OSA was defined as an REM:non-REM ratio of >2:1 and non-REM AHI <5events/h. Supine sleep time represented a greater proportion of total sleep time than REM sleep time (40% vs 13%). The prevalence of supine-only OSA was more than twofold greater than that of REM-only OSA (23% and 10%, respectively). The supine-only group had greater overall AHI (mean 12.6±6.1 vs 7.2±2.2 events/h; P<0.01) than the REM-only group. No significant differences in gender, age, or sleepiness were found between the two groups. Supine-only OSA is more common and is associated with a greater AHI than REM-only OSA.

Exploration of the relationship between sleep position and isolated tongue base or multilevel surgery in obstructive sleep apnea

This study aimed to elucidate the role of sleep position as a confounding factor on apnea hypopnea index (AHI) and surgical success in isolated tongue base or multilevel surgery. This study was conducted using retrospective analysis of patients who underwent hyoid suspension because of obstructive sleep apnea (OSA), in the St. Lucas Andreas Hospital, Amsterdam, The Netherlands, from 2004 to 2011. Concurrent surgical treatment was documented. Sleep positions and corresponding AHIs before and after surgery were compared. A total of 130 patients were included. 94 patients underwent surgery of base of tongue and palate (either uvulopalatopharyngoplasty or Z-palatoplasty), of whom 72 underwent concurrent radiofrequent thermotherapy of the base of tongue. 36 patients underwent base of tongue surgery alone, of whom 22 underwent concurrent radiofrequent thermotherapy of the base of tongue. 65 patients either had a successful reduction in AHI or in AI. Isolated tongue base or multilevel surgery was as successful on the supine AHI as it was on the AHI in other sleeping positions. Surgery was not more successful in the group with position-dependent patients as compared with the non-position-dependent patients (P = 0.615). Successful and non-successful surgical results could not be explained by variations in percentages of supine sleep position. Sleep position is not a confounding factor on surgical outcomes in tongue base surgery. The results of isolated base of tongue or multilevel surgery in position-dependent OSA patients leave room for improvement, possibly through positional therapy.

Diurnal Variation in Vascular Function: Role of Sleep

Although vascular function is lower in the morning than afternoon, previous studies have not assessed the influence of prior sleep on this diurnal variation. The authors employed a semiconstant routine protocol to study the contribution of prior nocturnal sleep to the previously observed impairment in vascular function in the morning. Brachial artery vascular function was assessed using the flow-mediated dilation technique (FMD) in 9 healthy, physically active males (mean ± SD: 27 ± 9 yrs of age), at 08:00 and 16:00 h following, respectively, 3.29 ± .37 and 3.24 ± .57 h prior sleep estimated using actimetry. Heart rate and systolic and diastolic blood pressures were also measured. The data of the experimental sleep condition were compared with the data of the “normal” diurnal sleep condition, in which FMD measurements were obtained from 21 healthy individuals who slept only during the night, as usual, before the morning test session. The morning-afternoon difference in FMD was 1 ± 4% in the experimental sleep condition compared with 3 ± 4% in the normal sleep condition (p = .04). This difference was explained by FMD being 3 ± 3% lower in afternoon following the prior experimental sleep (p = .01). These data suggest that FMD is more dependent on the influence of supine sleep than the endogenous circadian timekeeper, in agreement with our previous finding that diurnal variation in FMD is influenced by exercise. These findings also raise the possibility of a lower homeostatic “set point” for vascular function following a period of sleep and in the absence of perturbing hemodynamic fluctuation. (Author correspondence: h.jones1@ljmu.ac.uk)

Positional sensitivity as a confounder in diagnosis of severity of obstructive sleep apnea

The apnea-hypopnea index (AHI) is used to grade obstructive sleep apnea (OSA) into mild, moderate, and severe forms. Obstructive events are most common in the supine position. The amount of supine sleep thus influences total AHI. Our aim was to determine the prevalence of position-dependent OSA (POSA) and its relation to OSA severity classification as recommended by the American Academy of Sleep Medicine (AASM). Two hundred sixty-five subjects were recruited from primary care hypertension clinics. Whole-night respiratory recordings were performed to determine the AHI in the supine and non-supine positions, respectively. POSA was defined as supine AHI twice the non-supine AHI with supine AHI ≥5. Fifty-three percent had POSA, 22% had non-position-dependent OSA, and 25% had normal respiration. By AASM classification, 81 subjects did not have OSA, but 42% of them had some degree of obstruction when supine, and 5 subjects would have been classified as moderate-severe if they had only slept supine. Conversely, of the 53 classified as mild OSA, 30% would have changed to a more severe classification if they had exclusively slept supine. POSA was common both in subjects that by AASM classification had OSA as well as those without. The severity of OSA, as defined by AASM, could be dependent on supine time in a substantial amount of subjects.

Supine sleep and positional sleep apnea after acute ischemic stroke and intracerebral hemorrhage

OBJECTIVE:Obstructive sleep apnea is frequent during the acute phase of stroke, and it is associated with poorer outcomes. A well-established relationship between supine sleep and obstructive sleep apnea severity exists in non-stroke patients. This study investigated the frequency of supine sleep and positional obstructive sleep apnea in patients with ischemic or hemorrhagic stroke.METHODS:Patients who suffered their first acute stroke, either ischemic or hemorrhagic, were subjected to a full polysomnography, including the continuous monitoring of sleep positions, during the first night after symptom onset. Obstructive sleep apnea severity was measured using the apnea-hypopnea index, and the NIHSS measured stroke severity.RESULTS:We prospectively studied 66 stroke patients. The mean age was 57.6±11.5 years, and the mean body mass index was 26.5±4.9. Obstructive sleep apnea (apnea-hypopnea index ≥5) was present in 78.8% of patients, and the mean apnea-hypopnea index was 29.7±26.6. The majority of subjects (66.7%) spent the entire sleep time in a supine position, and positional obstructive sleep apnea was clearly present in the other 23.1% of cases. A positive correlation was observed between the NIHSS and sleep time in the supine position (rs = 0.5; p<0.001).CONCLUSIONS:Prolonged supine positioning during sleep was highly frequent after stroke, and it was related to stroke severity. Positional sleep apnea was observed in one quarter of stroke patients, which was likely underestimated during the acute phase of stroke. The adequate positioning of patients during sleep during the acute phase of stroke may decrease obstructive respiratory events, regardless of the stroke subtype.

Association between Positional Dependency and Obstruction Site in Obstructive Sleep Apnea Syndrome

ObjectivesThe purpose of this study is to find out associations between positional dependency and obstructive levels based on sleep videofluoroscopy (SVF) in patients with obstructive sleep apnea syndrome (OSAS).MethodsRetrospective review was made of 91 OSAS patients who underwent polysomnography and SVF from August 2009 through June 2010. Polysomnography variables including apnea-hypopnea index (AHI), supine AHI, non-supine AHI, time spent in supine sleep position of the total sleep time and positional dependency (PD) were analyzed. Obstruction sites were evaluated as SVF variables.ResultsOf 91 patients, 65 (71.4%) were positional patients (PP) and 26 (28.6%) were non-positional patients (NPP). An analysis of polysomnography variables according to PD revealed that overall AHI, non-supine AHI and supine AHI in PP was significantly lower than that in NPP. The patients with soft palate obstruction (SP type) were more likely to have PD than the patients with tongue base obstruction (TB type; P=0.046). PD was inversely related to OSAS severity significantly (P=0.001).ConclusionThese results provide evidence that positional dependent patients may have higher success rate of soft palate OSA surgery alone than non-positional dependent patients. Although PD may be associated with obstruction site, PD only itself may not be useful in planning surgical treatment for OSAS.

Swaddling

The supine sleep position is recommended to reduce sudden infant death syndrome risk. Swaddling may improve adherence with supine placement. To assess knowledge, attitudes, and practice regarding swaddling among adult caregivers of 0- to 3-month-old infants. Cross-sectional descriptive survey. All 103 adults interviewed had swaddled their infant. Common reasons for swaddling included infant comfort and warmth. Almost 80% of those who swaddled their infant found it effective, 80% believed it to be comfortable, and ~90% believed swaddling to be safe. Parents who routinely used swaddling were more likely to find it effective and to place their infant supine when swaddled (P < .01). Parents often use swaddling to comfort the infant, and most find it effective. Parents who routinely use swaddling are more likely to place their infant supine if swaddled. Swaddling may be a strategy for parents of infants who have difficulty sleeping in the supine position.

Accurate Position Monitoring and Improved Supine-Dependent Obstructive Sleep Apnea with a New Position Recording and Supine Avoidance Device

Approximately 30% of obstructive sleep apnea (OSA) patients have supine-predominant OSA, and simply avoiding supine sleep should normalise respiratory disturbance event rates. However, traditional supine-avoidance therapies are inherently uncomfortable, and treatment adherence is poor and difficult to monitor objectively. This study evaluated the efficacy of a novel, potentially more acceptable position monitor and supine-avoidance device for managing supine-predominant OSA and snoring. In-laboratory evaluation of position recording accuracy versus video recordings (validation study), and randomized controlled crossover trial of active versus inactive supine-avoidance therapy in the home setting (efficacy study). 17 patients undergoing in-laboratory sleep studies (validation) and 15 patients with supine-predominant OSA (efficacy). EFFICACY STUDY: 1 week of inactive and 1 week of active treatment in randomized order, separated by 1 week. Agreement between 30-sec epoch-based posture classifications from device versus video records was high (median κ 0.95, interquartile range: 0.88-1.00), and there was good supine time agreement (bias 0.3%, 95%CI: -4.0% to 4.6%). In the efficacy study, apnea-hypopnea index (AHI) and snoring frequency were measured in-home using a nasal pressure and microphone based system during inactive and active treatment weeks. The position monitoring and supine alarm device markedly inhibited supine time (mean ± SEM 19.3% ± 4.3% to 0.4% ± 0.3%, p < 0.001) and reduced AHI (25.0 ± 1.7 to 13.7 ± 1.1 events/h, p = 0.030) but not snoring frequency. This new position monitoring and supine alarm device records sleep position accurately and improves OSA but not snoring in patients with supine-predominant OSA.