A cross-sectional analysis of daytime versus nocturnal polysomnographic respiratory parameters in cystic fibrosis during early adolescence

Breathing patterns during sleep and their relationship with FEV1 in pediatric patients with cystic fibrosis residing at high altitude

Introduction

Sleep-disordered breathing (SDB) and gas exchange disorders are common in patients with cystic fibrosis (CF). Currently, the impact of the disease on sleep patterns in patients living at high altitude and the relationship of these patterns to lung function are largely unknown. The aim of this study was to determine the frequency of SDB in children with CF aged 6-18 years and the relationship between SDB and lung function (FEV1).

Methods

This is an analytical cross-sectional study of children aged 6-18 years diagnosed with CF. Spirometry before and after bronchodilators and polysomnography with capnography were performed. Descriptive analysis of qualitative and continuous variables was performed. Spearman's correlation coefficient was used to determine the correlation between polysomnogram and lung function (FEV1).

Results

Twenty-four patients with CF were included. The mean age was 10.5 ± 3.1 years and 62.5% were male. Nine children had bronchiectasis on chest CT. The median absolute baseline FEV1 was 1,880 (1,355-2,325) ml and 98% (83%-110%) of predicted value. No significant difference in FEV1% was observed between subjects with obstructive sleep apnea (OSA) and those without OSA (P = 0.56). The prevalence of OSA was 66.7% in children younger than 13 years and 40% in children older than 13 years. The Spearman correlation coefficient between FEV1 and percentage of total sleep time with saturation less than 90% (T90) was rho -0.52 (p-value = 0.018), and between FEV1 and percentage of total sleep time with saturation less than 85% (T85) was statistically significant with rho -0.45 (p-value = 0.041). A positive correlation was observed between FEV1 and SpO2 during sleep with rho 0.53 and a statistically significant p-value (0.014).

Conclusions

A high prevalence of sleep apnea was found in children with CF living at high altitude, with a negative correlation between FEV1 and T90 and T85 oxygenation indices, and a positive correlation between FEV1 and SpO2 during sleep.

Sleep in children with cystic fibrosis: More under the covers

Cystic fibrosis (CF) is a chronic multisystem disease with manifestations from birth. It involves the entire respiratory system, with increased cough, and recurrent pulmonary infections, and it also leads to intestinal malabsorption, all of which can have an impact on sleep. In this review, we summarize the available literature on the various sleep disturbances in children with CF. Sleep quality and sleep efficiency are often impaired in children with CF. They may be accompanied by symptoms associated with sleep-disordered breathing (SDB), and objective findings, such as nocturnal hypoxemia. Importantly, a strong association has been shown between SDB and the severity of lung disease, and some studies have reported a similar association for sleep quality. Further research is needed to better characterize the association of sleep disturbances with respiratory outcomes and the impact of treatment of sleep disorders on pulmonary status in children with CF.

Risk factors for obstructive sleep apnea in cystic fibrosis

INTRODUCTION

Despite emerging data that suggest a high frequency and severity of obstructive sleep apnea (OSA) among patients with cystic fibrosis (CF), few of them are referred for polysomnography. Little is known about which patients with CF are at increased risk for OSA and which sleep symptoms merit investigation.

METHODS

A single-center retrospective analysis of clinical and polysomnographic data from 2009, January 1 to October 31, 2020 in referred children and adults with CF.

RESULTS

Among 74 patients (42 children, 32 adults) with CF, 39 (53%) had OSA. No age or sex differences emerged in OSA frequency. Mean apnea-hypopnea index (AHI) was higher among overweight/obese adults (n = 16) as compared with adults of normal weight or underweight (11.4 vs. 6.2; p = 0.005). Adults with (n = 10) versus without a crowded oropharynx had 13.0 times greater odds of OSA (95% confidence interval (CI): 1.4, 121.4; p = 0.02). Children with (n = 24) versus without tonsillar hypertrophy had a higher risk for OSA (OR = 5.2; 95% CI: 1.4, 19.8; p = 0.02), as did children with (n = 10) versus without symptomatic chronic sinusitis (OR = 5.8; 95% CI: 1.1, 32.1; p = 0.04). Neither snoring, excessive daytime sleepiness, nor lung disease severity were associated with OSA.

CONCLUSION

Key risk factors for OSA may differ between children and adults with CF: upper airway pathology appears important in children and overweight/obesity or a crowded oropharynx in adults. Given the lack of sensitivity of snoring, daytime sleepiness, and lung disease severity, detection of OSA may require a low threshold for polysomnographic assessment in this vulnerable population.

Obstructive sleep apnea in children and adolescents with cystic fibrosis and preserved lung function or mild impairment: a systematic review and meta-analysis of prevalence

OBJECTIVE/BACKGROUND

Sleep disorders in cystic fibrosis may be present before daytime clinical manifestations, regardless of lung function impairment, affecting quality of life and disease progression. This study investigated the prevalence of obstructive sleep apnea in children and adolescents with cystic fibrosis and preserved lung function or mild impairment, and evaluated its association with clinical variables.

METHODS

A systematic review with meta-analysis of prevalence was conducted, including observational studies with polysomnographies in patients with cystic fibrosis who presented mean lung function values > 60% predicted. The methodological quality of the studies was analyzed, and a meta-analysis was performed to assess the prevalence of obstructive sleep apnea.

RESULTS

Of the 2318 studies identified, 7 were included in the systematic review and 6 in the meta-analysis of prevalence. The confounding factors and strategies identified were the items with greatest weakness in the methodological quality assessment. Most studies were cross-sectional, and sample size ranged from 9 to 67 individuals. The most frequent criterion for defining obstructive sleep apnea was apnea-hypopnea index (AHI) > 1 per hour. The prevalence found ranged from 32.3 to 100% and the pooled prevalence was 65% (I² = 53.4%), considering AHI>1, and 52% (I² = 89.4%) for AHI>2 per hour. It was not possible to verify the association between obstructive sleep apnea and clinical variables.

CONCLUSIONS

A high prevalence of obstructive sleep apnea in children and adolescents with cystic fibrosis was found, regardless of age and lung function impairment, reinforcing the importance of investigating sleep-disordered breathing during clinical visits even when lung function is not yet compromised.

Actigraphic and patient and family reported sleep outcomes in children and youth with cystic fibrosis: A systematic review

BACKGROUND

Sleep concerns are commonly reported by children and youth with cystic fibrosis (CF). Understanding normative sleep in the home environment and as reported from the perspective of patients and parents is a first step in responding to an important clinical concern and developing a sleep intervention strategy. This systematic review aimed to describe actigraphic and self/parent reported measures of sleep quantity; quality; and determine factors associated with poor sleep quantity and/or quality in children and youth (0-25yrs.) with CF.

METHODS

Five online databases; Medline, Embase, CINAHL, PsycInfo, and CENTRAL were searched for relevant articles from inception-February 2020. Studies reporting primary data, using either qualitative/quantitative methods or both were eligible for inclusion. Eligible full text articles were independently screened by two reviewers. Data from included studies were independently extracted and synthesized by one reviewer and accuracy verified independently by a second reviewer.

RESULTS

This review found 31 articles that met inclusion criteria. Analysis found evidence demonstrating that actigraphic SE was lower, actigraphic nighttime awakenings were greater, and self/parent-reported measures of sleep quality were poorer in children and youth with CF. Study findings related to actigraphic TST, WASO, and self/parent-reported sleep duration were mixed. Thirteen factors demonstrated an association with poor quality sleep.

CONCLUSIONS

In children and youth with CF, evidence exists of objectively measured sleep disturbance and poor self/parent reported sleep quality. Further longitudinal and comparative research studies are warranted to better understand sleep disturbance in this population. Clinically, sleep assessment should be an integral part of routine CF care.

Sleep-disordered breathing in cystic fibrosis

Sleep-disordered breathing (SBD) is an under recognized comorbidity in the cystic fibrosis (CF) population across the lifespan. Nocturnal hypoxemia, obstructive sleep apnea, and nocturnal hypoventilation are respiratory abnormalities that occur commonly during sleep in patients with lung disease, and have deleterious consequences to the quality of life in people with CF. Effective screening for these abnormalities is needed to allow for timely initiation of treatment, which has been reported to be efficacious. Lack of treatment leads to worsened pulmonary, cardiovascular, and metabolic outcomes in patients. In this review, we give an overview of SBD for the CF clinician, including prevalence, treatment, and suggestions for future research. We strongly encourage the CF community to incorporate evaluation for SBD in CF clinical care so that outcomes for the subset of the CF patients with comorbid SBD improve.

Sleep-disordered breathing and markers of morbidity in children and adolescents with cystic fibrosis

BACKGROUND

Studies have shown that sleep disorders occur in cystic fibrosis (CF) patients and may be present before daytime clinical manifestations.

OBJECTIVES

To evaluate the presence of sleep disorders among children and adolescents with CF, attempting to identify associations with pulmonary function, nutritional status, days in hospital, and days taking antibiotics.

METHODS

Individuals with a diagnosis of CF aged between 6 and 18 years were included. Information on sociodemographic, clinical profile, history of hospitalizations, and use of antibiotics in the last year were collected. Spirometry, bioimpedance, and polysomnography were performed. The presence of nocturnal hypoxemia and obstructive sleep apnea syndrome (OSAS) were evaluated and participants divided according to their presence.

RESULTS

Thirty-one patients were included. The prevalence of OSAS was 32.3% and nocturnal hypoxemia was 29.0%. Average nocturnal peripheral oxyhemoglobin saturation (SpO₂ ) correlated (P < .001) with forced vital capacity (r = .55) and forced expiratory volume in the first second (r = .62). The higher the percentage of total sleep time (TST) with SpO₂ less than 90%, the lower the pulmonary function. Individuals with OSAS and nocturnal hypoxemia had lower spirometric values compared to patients without these disorders, but the nocturnal hypoxemia group also had lower Shwachman-Kulczycki score, longer hospitalization time and antibiotic use. TST with SpO₂ less than 90% was associated with length of hospitalization (r²  = .53).

CONCLUSION

Children and adolescents with CF have sleep disorders, including OSAS (32.3%) and nocturnal hypoxemia (29%). Individuals with nocturnal hypoxemia presented lower lung function, worse clinical score, and higher morbidity. TST with SpO₂ less than 90% was associated with length of hospitalization.

Sleep-disordered breathing in cystic fibrosis

INTRODUCTION

Cystic fibrosis (CF) is a life-shortening, genetic disease that affects approximately 30,000 Americans. Although patients frequently report snoring, mouth breathing, and insomnia, the extent to which sleep-disordered breathing (SDB) may underlie these complaints remains unknown.

METHODS

Single-center retrospective review of polysomnography results from referred patients with and without CF individually-matched (1:2) for age, gender, race, and body mass index (BMI).

RESULTS

Mean ages were 8.0 ± 5.2 (sd) and 35.9 ± 12.9 years, among 29 children and 23 adults with CF respectively. The CF and non-CF groups were well-matched in age and BMI. Subjects with vs. without CF had three times greater odds of moderate-severe SDB (apnea-hypopnea index (AHI) ≥ 5 in children, ≥ 15 in adults) (p = 0.01). Nocturnal oxygen saturation nadir (Minimum SpO₂) was lower among CF vs. non-CF groups (p = 0.002). For every 1-unit increase in AHI, the decline in Minimum SpO₂ was larger for subjects with vs. without CF (p = 0.05). In subjects with CF, forced expiratory volume in 1 s percent predicted (FEV1 PPD) was associated with Minimum SpO₂ (Pearson r = 0.68, p < 0.0001) but not AHI (r = -0.19, p = 0.27). For every 1-unit increase in AHI, magnitude of decline in Minimum SpO₂ was larger for those with low vs. normal FEV1 PPD (p = 0.01).

CONCLUSION

Severity of SDB may be worse among referred patients with vs. without CF. The SDB may modify the relationship between CF lung disease and nocturnal hypoxemia. Markers of lung disease severity including lung function do not predict SDB severity, suggesting the need for routine polysomnography to screen for this sleep disorder.

Sleep disorders in cystic fibrosis: A systematic review and meta-analysis

Cystic fibrosis (CF) is a genetic disorder that leads to airway mucus accumulation, chronic inflammation, and recurrent respiratory infections - all likely impacting sleep. However, controlled studies of sleep in CF patients are limited, and have shown mixed results. We reviewed all publications on CF and sleep indexed in PubMed, CINAHL, and Scopus through April 2019. In the meta-analysis, we calculated pooled weighted mean differences for sleep quality, sleepiness, oximetry, and polysomnographic (PSG) parameters, using fixed or random-effects models as appropriate. A total of 87 manuscripts were reviewed. Compared to controls, children with CF had lower nighttime oxygen saturation nadirs, decreased sleep efficiency and a higher respiratory event index, with no differences in the percentage of REM sleep. Adults with CF had lower oxygen saturation nadirs, with a trend towards reduced sleep efficiency and no differences in REM sleep. In addition, patients with CF cough more during sleep and experience painful events that interfere with sleep. Actigraphy and questionnaires suggest disturbed sleep and daytime sleepiness. Noninvasive ventilation appears to improve gas exchange and symptoms. We conclude that when sleep is evaluated objectively or subjectively in patients with CF, perturbations are common, emphasizing the importance of their identification and treatment and inclusion as part of routine care. Additional research, with larger sample sizes and standardized outcomes, are necessary.

Sleep-disordered breathing in cystic fibrosis pediatric subjects

Objectives

To describe the frequency of sleep-disordered breathing (SDB) in pediatric cystic fibrosis (CF) and to study associations between polysomnographic respiratory parameters and available clinical information.

Methods

This was a retrospective, cross-sectional study. The sample data were obtained from information recorded on patient charts in 2015 and 2016. The study included all individuals with CF aged from 2 to 20 years for whom records were available for polysomnography performed within the previous two years.

Results

Sixteen individuals with CF (mean age 11 ± 5.6 years old) were included. Polysomnographic respiratory parameter abnormalities were defined as an apnea-hypopnea index (AHI) exceeding one event per hour of sleep or an oxyhemoglobin saturation (SpO₂) nadir below 90%; observed in 10 subjects (62.5%). Forced expiratory volume in first second (FEV₁) was correlated (r=0.602, p=0.023) with mean sleep SpO₂. FEV₁ was also negatively correlated with sleep peak end-tidal carbon dioxide (EtpCO₂) (r=-0.645, p=0.024). Additionally, chronic airway colonization by Pseudomonas aeruginosa was associated with mean EtpCO₂ in non-REM sleep (p=0.024).

Discussion

SDB was frequently observed in this sample of children with CF. There was an association between CF respiratory disease progression markers and sleep breathing parameters in children. Sleep studies appear to be an important tool for assessment of the respiratory status of these individuals with CF, although further studies are needed, especially with carbon dioxide sleep analysis.

Cystic fibrosis year in review 2017

In this article, we highlight cystic fibrosis (CF) reports published in Pediatric Pulmonology during 2017. We also include articles from a variety of journals that are related or are of special interest to clinicians.

Sleep disturbances and their impact in pediatric cystic fibrosis

Cystic fibrosis is a chronic, life-shortening illness that affects multiple systems and results in frequent respiratory infections, chronic cough, fat malabsorption and malnutrition. Poor sleep is often reported by patients with cystic fibrosis. Although objective data to explain these complaints have been limited, they do show poor sleep efficiency and frequent arousals. Abnormalities in gas exchange are also observed during sleep in patients with cystic fibrosis. The potential impact of these abnormalities in sleep on health and quality of life remains largely unstudied. This review summarizes what is known about sleep in children with cystic fibrosis, and implications for clinical practice. This report also highlights new evidence on the impact of sleep problems on disease-specific outcomes such as lung function, and identifies areas that need further exploration.