Abstract P105: Sleep Disordered Breathing and Cardiac Autonomic Modulation in Adolescents - Penn State Child Cohort (PSCC) Study

Objectives: To investigate the relationship between sleep disordered breathing (SDB) and cardiac autonomic modulation (CAM) in a population-based sample of adolescents. Methods: We used available data from 400 adolescents who completed the follow up examinations in the population-based PSCC study. 1-night polysomnography was used to assess apnea hypopnea index (AHI). AHI was used to define no-SDB (AHI<1), mild SDB (1≤AHI<5), and moderate SDB (AHI≥5). CAM was assessed by heart rate variability (HRV) analysis of beat-to-beat normal R-R intervals from a 39-hour high resolution Holter ECG. The HRV indices in frequency domain [high frequency power (HF), low frequency power (LF), and LF/HF ratio] and time domain [standard deviation of normal RR intervals (SDNN), and the square root of the mean squared difference of successive normal RR intervals (RMSSD), and heart rate (HR)] were calculated on a 30-minute basis (78 repeated measures). Mixed-effects models were used to assess the SDB and HRV relationship. Results: The mean age was 16.9 yrs (SD=2.19), with 54% male and 77% white. The mean (SD) AHI were 0.52 (0.26), 2.38 (1.03), and 12.27 (14.54) for no-, mild-, and moderate-SDB participants. The age, race, sex, and BMI percentile adjusted mean (SE) HRV indices across three SDB groups are presented in Table 1. In summary, sleep disordered breathing was associated with lower HRV and higher HR in this population-based adolescent sample, with a significant dose-response relationship. Conclusion: moderate SDB in adolescents is already associated with lower HRV, indicative of sympathetic activation and lower parasympathetic modulation, which has been associated with cardiac events in adults.

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Abstract P200: The Circadian Pattern of Cardiac Autonomic Modulation and its Correlates in Adolescents- Penn State Child Cohort (PSCC) Study

Circulation ◽

10.1161/circ.129.suppl_1.p200 ◽

2014 ◽

Vol 129 (suppl_1) ◽

Author(s):

Sol M Rodriguez-Colon ◽

Fan He ◽

Edward O Bixler ◽

Julio Fernandez-Mendoza ◽

Susan Calhoun ◽

...

Keyword(s):

Heart Rate ◽

Low Frequency ◽

Population Based ◽

Autonomic Modulation ◽

Circadian Pattern ◽

Late Afternoon ◽

Cardiac Autonomic Modulation ◽

Penn State ◽

State Child ◽

The Mean

Objective: To examine the circadian pattern of cardiac autonomic modulation (CAM) and its correlates in a population-based sample of adolescents. Methods: We used the data from 400 adolescents who completed the follow up exam in the PSCC study. CAM was assessed by heart rate variability (HRV) analysis of beat-to-beat normal R-R intervals from a 24-hour (7:00 PM to 7:00 PM) ECG, on a 30-minute basis (48 segments/person). The HRV indices included frequency domain: [high and low frequency powers (HF, LF), and LF/HF ratio] and time domain: [standard deviation of normal RRs (SDNN), and the square root of the mean squared difference of successive normal RRs (RMSSD), and heart rate (HR)]. We used a cosine periodic model to estimate each participant’s circadian parameters: mean (M), amplitude (Â), and crescent time (θ). We then used mixed-effects models to calculate group level circadian pattern as the overall M, Â of the oscillation, and θ of the highest oscillation. Results: The mean age was 16.9 yrs (SD=2.2), with 54% male and 77% white. The mean BMI percentile is 61, with 16% were obese (BMI percentile ≥ 95). Overall, the parasympathetic modulation gradually increases from late afternoon throughout the evening, and reaches the peak amplitude around 3:00 AM, at which it gradually decrease throughout most of the daytime until late afternoon. The age, sex and race showed varying differences on the CAM circadian parameters. In contrast, obesity in adolescents had adverse effects on all three circadian parameters. Using HF (a reliable index of parasympathetic modulation) as an example, the circadian pattern of the entire sample, and stratified by obesity are shown in Figure 1. Conclusion: Circadian pattern of CAM can be quantified by three cosine parameters (M, Â, and θ). Obesity in adolescents is already associated with a CAM profile indicative of sympathetic overflow and reduced parasympathetic modulation, at all levels of the CAM circadian rhythm.

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Abstract WP357: Prevalence of Pre- and Post-intracerebral Hemorrhage Sleep-disordered Breathing

Stroke ◽

10.1161/str.48.suppl_1.wp357 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Richard V Scheer ◽

Lynda D Lisabeth ◽

Chengwei Li ◽

Erin Case ◽

Ronald D Chervin ◽

...

Keyword(s):

Ischemic Stroke ◽

Intracerebral Hemorrhage ◽

Mexican American ◽

Sleep Disordered Breathing ◽

Population Based ◽

Apnea Hypopnea Index ◽

Berlin Questionnaire ◽

Portable Monitor ◽

Before And After ◽

Disordered Breathing

Background: Sleep-disordered breathing (SDB) is an independent risk factor for stroke. The reported prevalence of SDB after stroke ranges from 60 to >70%, while the pre-stroke prevalence of SDB is less well described. Moreover, much of these data are derived from ischemic stroke or mixed ischemic stroke and intracerebral hemorrhage (ICH) cohorts. Studies that assess the prevalence of SDB before and after ICH are lacking, with only one prior study (n=32) that reported a post-ICH SDB prevalence of 78%. We report herein the results of a second, larger, prospective study that assessed the prevalence of pre- and post-ICH. Methods: Participants enrolled in the population-based stroke surveillance study, the Brain Attack Surveillance in Corpus Christi (BASIC) project, with ICH from 2010-2015 were screened for SDB with the well validated ApneaLink Plus portable monitor (SDB defined as apnea-hypopnea index (AHI) ≥10). The Berlin questionnaire was administered, with reference to the pre-ICH state, to assess for possible pre-stroke SDB. Results: Of the 60 ICH participants screened, the median age was 63 years (interquartile range (IQR): 55.5, 74.5). Twenty-one (35%) were female, 54 (90%) were Mexican American, and 53 (88%) had a history of hypertension. The median Glasgow Coma Scale score was 15.0 (IQR: 15.0, 15.0) and the median NIHSS was 5.5 (IQR: 1.5, 8.0). Post-ICH, the median AHI was 9.5 (IQR: 5.5, 19.0); almost half (46.7%) met criteria for SDB. Thirty-four participants (56.7%) screened as high risk for SDB pre-ICH. Conclusion: Sleep-disordered breathing was highly prevalent after ICH, and also likely common before ICH, in this mostly Mexican American, community-based sample. If SDB increases risk for ICH, the findings suggest a potential new treatment target to prevent ICH and recurrent ICH.

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0890 Sleep Disordered Breathing is Associated With Endothelial Dysfunction and Atherosclerosis in Young Adults: Preliminary Longitudinal Findings in the Penn State Child Cohort

SLEEP ◽

10.1093/sleep/zsaa056.886 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A339-A339

Author(s):

J Fernandez-Mendoza ◽

Z Gao ◽

K Brandt ◽

L Houser ◽

S L Calhoun ◽

...

Keyword(s):

Young Adults ◽

Endothelial Dysfunction ◽

Young Adulthood ◽

Sleep Disordered Breathing ◽

Population Based ◽

Apnea Hypopnea Index ◽

Penn State ◽

State Child ◽

Disordered Breathing

Abstract Introduction Sleep disordered breathing (SDB) in middle-age is an established risk factor for cardiovascular disease. However, population-based studies supporting its cardiovascular contribution at earlier stages of development are lacking, particularly with long-term follow-ups. Methods The Penn State Child Cohort is a population-based longitudinal sample of 700 children (8.7±1.7y), of whom 421 were followed-up 8.3 years later during adolescence (17.0±2.3y) with in-lab polysomnography (PSG). To date, 425 have been followed-up another 7.4 years later during young adulthood (24.4±2.6y) via a standardized survey and 136 of them (55.1% female, 21.3% racial/ethnic minority) have undergone a repeat of their PSG to ascertain apnea/hypopnea index. Subjects (n=121) also underwent Doppler ultrasounds to assess flow-mediated dilation (FMD) and carotid intima-media thickness (CIMT). Linear regression models stratified by body mass index in young adulthood. Results SDB was cross-sectionally associated with lower FMD (β=-0.239, p=0.008) and greater CIMT (β=0.330, p<0.001) in young adulthood. Longitudinally, childhood (n=121) and adolescence (n=90) SDB were significantly associated with CIMT (β=0.327, p<0.001 and β=0.286, p=0.006, respectively), but not with FMD (β=-0.158, p=0.08 and β=-0.101, p=0.35, respectively). These associations, particularly longitudinal ones between childhood and adolescence SDB with CIMT in young adulthood, were stronger in overweight than normal weight subjects (e.g., β=0.310, p=0.030 and β =0.089, p=0.582, respectively). Conclusion SDB and obesity appear to be synergistically associated with endothelial dysfunction and atherosclerosis in young adults from the general population. These data suggest that a childhood exposure to chronic SDB is associated with long-term atherosclerosis, while endothelial dysfunction may be a short-term outcome. This ongoing 16-year longitudinal study will test whether the natural history of SDB from childhood through adolescence into young adulthood shows differential trajectories for cardiovascular morbidity. Support National Institutes of Health (R01HL136587, R01HL97165, R01HL63772, UL1TR000127)

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Role of Type and Volume of Recreational Physical Activity on Heart Rate Variability in Men

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17082719 ◽

2020 ◽

Vol 17 (8) ◽

pp. 2719 ◽

Cited By ~ 1

Author(s):

Shaea Alkahtani ◽

Andrew A. Flatt ◽

Jawad Kanas ◽

Abdulaziz Aldyel ◽

Syed Shahid Habib

Keyword(s):

Physical Activity ◽

Heart Rate ◽

Time Domain ◽

Active Group ◽

Control Groups ◽

Rr Intervals ◽

The Mean ◽

And Control ◽

Arab Men ◽

Frequency Power

The aim of this study was to investigate the effect of recreational aerobic physical activity (PA) type and volume on heart rate variability (HRV) in Arab men. This was a retrospective, cross-sectional study, and included men (n = 75, age = 37.6 ± 7.1 years, body mass index (BMI) = 26.7 ± 3.1 kg/m2) who were members of a walking group, cycling group, or were inactive controls. Monthly distances from the past three months were obtained from walking and cycling groups, and the volume of PA was classified into three subgroups (high, moderate, low). HRV was measured using a computerized electrocardiographic data acquisition device. R–R interval recordings were performed while participants rested in a motionless supine position. RR intervals were recorded for 15 minutes, and a five-minute segment with minimal ectopic beats and artifacts was selected for HRV analysis. Time-domain parameters included the mean R–R interval, standard deviation of the mean R–R interval (SDNN), and root-mean-squared difference of successive RR intervals (RMSSD). The frequency-domain parameters included high-frequency power (HF), low-frequency power (LF), and LF to HF ratio (LF/HF). Results showed that there were no significant differences between walking, cycling, and control groups for all HRV parameters. Time-domain analyses based on PA volume showed that age-adjusted SDNN for the high-active group was greater than the low-active group (P = 0.03), and RMSSD for the moderate-active group was greater than the control group (P = 0.009). For the frequency domain, LF for the high-active group was greater than the low-active and control groups (P = 0.006), and HF for the moderate-active group was greater than the low-active group (P = 0.04). These data indicate that walking >150 km per month, or cycling >100 km per month at a speed >20 km/h may be necessary to derive cardiac autonomic benefits from PA among Arab men.

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Validation of the NoSAS Score for the Screening of Sleep-Disordered Breathing in a Sleep Clinic

Canadian Respiratory Journal ◽

10.1155/2020/4936423 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Yi Rong ◽

Shihan Wang ◽

Hui Wang ◽

Feng Wang ◽

Jingjing Tang ◽

...

Keyword(s):

Predictive Value ◽

Sleep Disordered Breathing ◽

Screening Tool ◽

Characteristic Curve ◽

Population Based ◽

Screening Tools ◽

Apnea Hypopnea Index ◽

Portable Monitor ◽

Number Of Patients ◽

Disordered Breathing

Background. There is a growing number of patients with sleep-disordered breathing (SDB) referred to sleep clinics. Therefore, a simple but useful screening tool is urgent. The NoSAS score, containing only five items, has been developed and validated in population-based studies. Aim. To evaluate the performance of the NoSAS score for the screening of SDB patients from a sleep clinic in China, and to compare the predictive value of the NoSAS score with the STOP-Bang questionnaire. Methods. We enrolled consecutive patients from a sleep clinic who had undergone apnea-hypopnea index (AHI) testing by type III portable monitor device at the hospital and completed the STOP-Bang questionnaire. The NoSAS score was assessed by reviewing medical records. Sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) of both screening tools were calculated at different AHI cutoffs to compare the performance of SDB screening. Results. Of the 596 eligible patients (397 males and 199 female), 514 were diagnosed with SDB. When predicting overall (AHI ≥ 5), moderate-to-severe (AHI ≥ 15), and severe (AHI ≥ 30) SDB, the sensitivity and specificity of the NoSAS score were 71.2, 80.4, and 83.1% and 62.4, 49.3, and 40.7%, respectively. At all AHI cutoffs, the AUC ranged from 0.688 to 0.715 for the NoSAS score and from 0.663 to 0.693 for the STOP-Bang questionnaire. The NoSAS score had the largest AUC (0.715, 95% CI: 0.655–0.775) of diagnosing SDB at AHI cutoff of ≥5 events/h. NoSAS performed better in discriminating moderate-to-severe SDB than STOP-Bang with a marginally significantly higher AUC (0.697 vs. 0.663, P=0.046). Conclusion. The NoSAS score had good performance on the discrimination of SDB patients in sleep clinic and can be utilized as an effective screening tool in clinical practice.

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Sleep-disordered breathing and cardiac autonomic modulation in children

Sleep Medicine ◽

10.1016/j.sleep.2009.11.012 ◽

2010 ◽

Vol 11 (5) ◽

pp. 484-488 ◽

Cited By ~ 43

Author(s):

Duanping Liao ◽

Xian Li ◽

Sol M. Rodriguez-Colon ◽

Jiahao Liu ◽

Alexandros N. Vgontzas ◽

...

Keyword(s):

Sleep Disordered Breathing ◽

Autonomic Modulation ◽

Cardiac Autonomic Modulation ◽

Disordered Breathing

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0597 Precision of Sleep-Disordered Breathing Event Classification Using Simulated Home Sleep Apnea Testing in Patients with Spinal Cord Injury, or Disease

SLEEP ◽

10.1093/sleep/zsaa056.594 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A228-A229

Author(s):

S Zeineddine ◽

A Sankari ◽

k Arvai ◽

A Salloum ◽

Y Abu Awad ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Patient Population ◽

Sleep Disordered Breathing ◽

Apnea Hypopnea Index ◽

Respiratory Events ◽

Respiratory Event ◽

Cord Injury ◽

The Mean ◽

Disordered Breathing

Abstract Introduction Sleep-disordered breathing (SDB) is highly prevalent among patients with spinal cord injury or disease (SCI/D). In-laboratory polysomnography (PSG) is difficult for these patients due to functional limitations and the physical construction of most sleep laboratories. Our objective was to evaluate the concordance between simulated HSAT and PSG in identifying SDB severity and subtypes of respiratory events in this patient population. Methods Within a larger study, 33 Veterans with SCI/D completed one night of in-laboratory PSG. Limited-channel HSAT was simulated by extracting 5 channels from PSG signals to include nasal pressure, thermistor, thoracic and abdominal belts, and oxygen saturation. Results Mean age of patients was 59.8 ± 10.9 years; 87.9% were male, and the average BMI was 28.1 ± 6.3. The mean Apnea-Hypopnea Index (AHI) from PSG was 35.5 ± 22.7. The mean Respiratory Event Index (REI) based on simulated HSAT was 22.5 ± 18.6. Thirty-one patients (93.9%) had SDB defined as AHI ≥5/hour. Simulated limited-channel HSAT accurately identified 32 out of 33 patients (96.96%). When SDB was further classified into mild (AHI 5-15 events/hr), moderate (AHI 15-30 events/hr), and severe (AHI>30/hr), simulated HSAT consistently underestimated the severity of underlying SDB. Spearman correlation between estimating AHI (PSG-HSAT) and subtypes of respiratory events was primarily accounted for by the difference in the number of hypopneas (r=0.72, -0.021 and -0.001 for hypopneas, obstructive and central apneas, respectively). Conclusion Our findings support the diagnostic utility of HSAT in SCI/D patients with SDB; however, HSAT underestimation of SDB may lead to difficulties in optimizing therapy. The misclassification of SDB severity is mainly driven by the number of hypopneas. Classification of hypopneas as obstrcutive or central may shed further light on the nature of this difference. Further research on the usability of HSAT devices in this patient population is needed. Support VA Rehabilitation Research and Development Service (RX002116; PI Badr and RX002885; PI Sankari) and NIH/NHLBI (K24HL143055; PI: Martin)

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Abstract 038: Cumulative Exposure To Sleep Disordered Breathing From Childhood Through Young Adulthood Is Associated With Impaired Endothelial Function

Circulation ◽

10.1161/circ.143.suppl_1.038 ◽

2021 ◽

Vol 143 (Suppl_1) ◽

Author(s):

Julio Fernandez-Mendoza ◽

Zhaohui Gao ◽

Myra Qureshi ◽

Baadal A Vachhani ◽

Jiangang Liao ◽

...

Keyword(s):

Young Adults ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Young Adulthood ◽

Sleep Disordered Breathing ◽

Population Based ◽

Cumulative Exposure ◽

Time Points ◽

The Mean ◽

Disordered Breathing

Introduction: Clinical and population-based studies in adults have shown that sleep disordered breathing (SDB) is associated with impaired endothelial function. However, there is a lack of population-based studies demonstrating an association between SDB and endothelial dysfunction in young adults using a developmental approach. Hypothesis: Exposure to SDB since childhood is associated with long-term impaired flow-mediated dilation (FMD) in young adulthood. Methods: We tested this hypothesis in a subsample of the Penn State Child Cohort, a population-based study of 700 children (median age 9y), of whom 421 were followed-up 6-13 years later during adolescence (median age 16y), and 178 have been followed-up 11-19 years later during young adulthood (median age 24y). Subjects (54.5% female, 20.8% racial/ethnic minority) underwent in-lab polysomnography to ascertain the apnea/hypopnea index (AHI) at all three time points, and ultrasounds to assess FMD in young adulthood. Based on the AHI truncated at ≥5 events/hour of sleep to include subjects already on positive airway pressure therapy, we averaged the exposure to AHI over the three time points (cAHI). The study outcomes were FMD, as a continuous measure, and endothelial dysfunction, defined as FMD<10.3% based on the median of the sample. Linear and logistic regression models simultaneously adjusted for sex, age, race/ethnicity, overweight and length of follow-up. Results: The mean cAHI was 1.31 (1.35) ranging from 0 to 5 and the mean FMD was 0.11 (0.04) ranging from 0.03 to 0.25. Linear models showed that cAHI was associated with significantly lower FMD in young adulthood (β = -0.006; 95% CI = -0.011, -0.0013; p = 0.014). To test the robustness of the analysis, we applied the same model with the square root of FMD as the outcome and similar results were obtained (β = -0.009; 95% CI = -0.016, -0.0017; p = 0.015). Logistic models showed that each point increase in cAHI was associated with 51% higher odds of endothelial dysfunction in young adulthood (OR = 1.51; 95% CI = 1.14, 2.06; p = 0.006). Conclusions: The preliminary data of this ongoing longitudinal study indicates that exposure to SDB during early stages of life is associated with increased risk for cardiovascular disease in young adults from the general population.

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Evidence for time-dependent autonomic cardiac reinnervation in children subsequent to transplantation of the heart

Cardiology in the Young ◽

10.1017/s1047951100003188 ◽

1996 ◽

Vol 6 (1) ◽

pp. 12-19

Author(s):

Joachim Kreuder ◽

Heinrich Netz ◽

Thomas Paul ◽

Andreas Müller ◽

Jürgen Bauer ◽

...

Keyword(s):

Heart Rate ◽

Standard Deviation ◽

Time Domain ◽

Recovery Time ◽

Cardiac Transplantation ◽

Sinus Node ◽

Time Dependent ◽

Rr Intervals ◽

The Mean ◽

Frequency Power

AbstractAutonomic denervation has been assumed to persist after orthotopic heart transplantation. Analyzing spontaneous and induced variations of heart rate, the status of autonomic cardiac innervation was investigated in six children 19–37 months after cardiac transplantation. The age at the time of transplantation varied from three weeks to 15.4 years. Heart rate variability was assessed on 24-hour Holter recordings by calculating time-domain indices (standard deviation of all RR intervals; standard deviation of the mean RR intervals from successive five-minute periods; mean of the standard deviations of RR intervals from successive five-minute periods; proportion of adjacent RR intervals > 50 msec different; square root of mean square successive differences in RR intervals) and frequency-domain variables (low frequency power, high frequency power and total spectrum power). Sinus node recovery time, sinoatrial conduction time and post-pacing cycle lengths were examined at different rates of endocardial atrial pacing. After the first year subsequent to transplantation, standard deviation of the mean RR intervals reached the normal range in four patients, whereas the other time-domain variables became normal in two patients. Both patients displayed normal or near-normal power spectrums of heart rate with normal day-to-night variations. For the remaining patients, spectrums of heart rate failed to show the main frequency peaks. Only the patient with normal variability in heart rate exhibited a decrease in corrected sinus node recovery time at higher stimulation rates, shortening of the first recovery cycle below the pre-pacing level, and a rapid decline of the accelerated post-pacing heart rate as described in innervated hearts. These results suggest the evolution of time-dependent efferent autonomic reinnervation after cardiac transplantation in children.

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Sleep characteristics and cognitive impairment in the general population

Neurology ◽

10.1212/wnl.0000000000003557 ◽

2016 ◽

Vol 88 (5) ◽

pp. 463-469 ◽

Cited By ~ 45

Author(s):

José Haba-Rubio ◽

Helena Marti-Soler ◽

Nadia Tobback ◽

Daniela Andries ◽

Pedro Marques-Vidal ◽

...

Keyword(s):

Cognitive Impairment ◽

General Population ◽

Sleep Disordered Breathing ◽

Neuropsychological Test ◽

Population Based ◽

Apnea Hypopnea Index ◽

Clinical Dementia Rating ◽

Sleep Complaints ◽

Confounding Variables ◽

Disordered Breathing

Objective:To assess the association between sleep structure and cognitive impairment in the general population.Methods:Data stemmed from 580 participants aged >65 years of the population-based CoLaus/PsyCoLaus study (Lausanne, Switzerland) who underwent complete sleep evaluation (HypnoLaus). Evaluations included demographic characteristics, personal and treatment history, sleep complaints and habits (using validated questionnaires), and a complete polysomnography at home. Cognitive function was evaluated using a comprehensive neuropsychological test battery and a questionnaire on the participant's everyday activities. Participants with cognitive impairment (global Clinical Dementia Rating [CDR] scale score > 0) were compared with participants with no cognitive impairment (global CDR score = 0).Results:The 291 participants with a CDR score > 0 (72.5 ± 4.6 years), compared to the 289 controls with CDR = 0 (72.1 ± 4.6 years), had significantly more light (stage N1) and less deep (stage N3) and REM sleep, as well as lower sleep efficiency, higher intrasleep wake, and higher sleepiness scores (all p < 0.05). Sleep-disordered breathing was more severe in participants with cognitive impairment with an apnea/hypopnea index (AHI) of 18.0 (7.8–35.5)/h (p50 [p25–p75]) (vs 12.9 [7.2–24.5]/h, p < 0.001), and higher oxygen desaturation index (ODI). In the multivariate analysis after adjustments for confounding variables, the AHI and the ODI ≥4% and ≥6% were independently associated with cognitive impairment.Conclusions:Participants aged >65 years with cognitive impairment have higher sleepiness scores and a more disrupted sleep. This seems to be related to the occurrence of sleep-disordered breathing and the associated intermittent hypoxia.

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