Obstructive sleep apnea and history of asthma in snoring children

Obstructive sleep apnea in asthmatic children: a cross-sectional study about prevalence and risk factors

OBJECTIVES

Primary objectives were to analyze the prevalence of obstructive sleep apnea in (1) boys and girls, and (2) severe asthma versus moderate and mild cases. The authors hypothesized that girls and severe asthma would have a higher prevalence of obstructive sleep apnea.

METHODS

Cross-sectional evaluation of asthmatic children attending a tertiary Pediatric Pulmonology clinic. The authors performed a history, physical examination, pulmonary function test, and home sleep apnea test.

RESULTS

The authors studied 80 consecutive patients, 7-18 years old, mean age of 11.6 years (standard deviation 2.7), 51.3% female, and 18.5% obese. Pulmonary function tests were obtained from 80 volunteers, 45% with obstruction pattern. Home sleep apnea tests were available from 76 volunteers, with a mean obstructive respiratory index of 1.8 events/h. Obstructive sleep apnea was found in 49 volunteers (61.2%). The authors did not find associations between obstructive sleep apnea and sex or asthma severity.

CONCLUSIONS

Obstructive sleep apnea was frequent among these asthmatic children. Sex and asthma severity were not risk factors. Considering the interrelationship of both diseases, it is worth keeping in mind the possibility of obstructive sleep apnea among children and teenagers with asthma.

Sleep disorders in children with asthma

Asthma and sleep disorders are both common in childhood, and often co-exist in the same child. Moreover, studies have shown that in many children the rate of one is influenced by the other. Sleep disorders can be classified into six different groups-insomnia, hypersomnia, parasomnia, movement disorders, circadian disorders, and sleep-related breathing disorders. Children with asthma often present with complaints of insomnia with poor sleep quality, difficulty falling asleep and sleep disruptions. These complains are often associated with asthma control. They may also complain of daytime sleepiness and have higher rates of parasomnias, such as night terrors and nocturnal enuresis when compared with their healthy peers. Whether movement and circadian disorders are also more prevalent in children with asthma is less clear. Finally, there is a complex bidirectional interaction between sleep-related breathing disorders and asthma: poor sleep and sleep disorders may worsen asthma, and asthma, particularly when it is poorly controlled, may impair sleep. In the current review we examine the association of each of the sleep disorders with asthma and review the common pathophysiological pathways. We hope to convince the reader that appropriate management of asthma must include inquiries into the patient's sleep, and vice versa.

Evaluation of obesity and asthma as risk factors for moderate to severe obstructive sleep apnea in children

STUDY OBJECTIVES

Asthma and obesity are risk factors for obstructive sleep apnea (OSA) in children but their link to OSA severity is uncertain. We aimed at determining whether asthma or obesity were associated with an increased risk of moderate/severe OSA.

METHODS

Children undergoing a one-night polysomnography for suspicion of OSA were retrospectively included. Univariate and multivariate analyses were conducted to assess the clinical and demographic characteristics linked to moderate/severe OSA (obstructive apnea-hypopnea index ≥ 5/h of sleep) with odds ratio (OR) and 95% confidence interval reported.

RESULTS

490 children (311 (64%) boys) were included with a median [25th; 75th percentile] age of 8.7 [5.4; 12.9] years, 164 (33%) non-asthmatics non-obese, 122 (25%) obese non-asthmatics, 125 (26%) asthmatics non-obese, 79 (16%) asthmatics and obese. Moderate/severe OSA was present in 157 (32%) children (75/157 (48%) obese and 52/157 (33%) asthmatics). Independent factors associated with increased or decreased risk of moderate/severe OSA were: obesity and male sex (OR 1.82 [1.16; 2.87], P = 0.01, and 1.55 [1.02; 2.36], P = 0.04, respectively), and current asthma, age >6 years or behavioral disorders (OR 0.45 [0.29; 0.70], P < 0.001; 0.44 [0.27; 0.73], P < 0.001; and 0.55 [0.33; 0.92], P = 0.02, respectively). Abnormal resistance of the respiratory system (measured in 241 children), but not abnormal spirometry (measured in 213 children), increased the risk of moderate/severe OSA (OR 2.95 [1.46-5.96], P = 0.003).

CONCLUSIONS

In our cohort enriched in obese and asthmatic children, obesity was associated with higher risk of moderate/severe OSA whereas current asthma was not.

Asthma and obstructive sleep apnoea in adults and children - an up-to-date review

Obstructive sleep apnoea (OSA) and asthma are two common respiratory disorders in children and adults. Apart from common risk factors, such as obesity, gastroesophageal reflux disease and allergic rhinitis, emerging evidence suggest that the two diseases may complicate the clinical course of each other. On one hand, OSA modifies asthmatic airway inflammation and is associated with poor asthma control. On the other hand, asthma and its medications increase the collapsibility of the upper airways contributing to the development and worsening of OSA. The overnight respiratory symptoms of OSA and asthma are often similar, and an inpatient polysomnography is often necessary for a proper diagnosis, especially in children. Continuous positive pressure, the gold standard treatment for OSA can improve asthma control in patients suffering from both diseases. However, there is limited evidence how anti-asthma medications act in the same patients. Nevertheless, adenotonsillectomy seems to be effective in children with concomitant asthma and OSA. This review summarises the evidence for the bidirectional link between asthma and OSA, focuses on diagnostic and therapeutic challenges and highlights the need for further research.

Subjective sleep-related breathing disorders and executive function in children with intermittent or mild persistent asthma

OBJECTIVE

The impact on executive function performance of sleep-related disorders in asthmatic children has been scarcely studied in community settings. The aims of the present study were to assess the prevalence of sleep-related breathing disorders (SRBD) in children with intermittent or mild persistent asthma in primary care settings, and to examine the possible correlations with measures of executive function.

METHODS

We performed a case-control study including 76 children with asthma (intermittent or mild persistent) and 85 healthy controls. The parents of both patients and controls completed the Paediatric Seep Questionnaire (PSQ) and the Behaviour Rating Inventory of Executive Function (BRIEF) questionnaire.

RESULTS

We did not find any statistically significant differences regarding the scales of PSQ. Additionally, there were no statistical differences between asthmatic children and controls regarding the scales of the BRIEF questionnaire. In both asthmatic children and controls the score of the scale of obstructive sleep-related breathing disorder was significantly correlated with the T scores of the two composite scales (BRI and MI) and the Global Executive Composite.

CONCLUSION

In children with intermittent or mild persistent asthma under the care of private general paediatricians there were no statistically significant differences regarding subjective SBD compared to the healthy controls. Also there were no statistical differences between asthmatic children and controls regarding behavioural correlates of executive function during everyday life.

Asthma and obesity as predictors of severe obstructive sleep apnea in an adolescent pediatric population

OBJECTIVE

To study a cohort of children referred for full-night polysomnography (PSG) due to suspicion of obstructive sleep apnea (OSA). We examined the relationship between asthma, obesity, and severe OSA (sOSA).

METHODS

We performed a retrospective case control analysis of children, ages 9 to 17 years, who underwent full-night PSG. The primary goal was to determine the association between asthma, obesity, and sOSA (apnea-hypopnea index ≥10). We used multiple logistic regression analysis to estimate these associations after controlling for covariates. A P value of ≤.05 was considered significant.

RESULTS

The study included 367 children (mean [standard deviation] age 14 years (1.7), 56% male, 43% Hispanic). The prevalence of asthma was 188 of 367 (52%); obesity was 197 of 367 (54%); and sOSA was 109 of 367 (30%). sOSA was less likely in asthmatics (coefficient = -0.59; standard error [SE] = 0.23; P = .01; odds ratio [OR] = 0.55; 95% confidence interval [CI] = 0.34 to 0.88) and more likely with obesity (coefficient = 0.89; SE = 0.24; P < .001; OR = 2.4; 95% CI = 1.5 to 3.9). The presence of asthma reduced the likelihood of sOSA by an average of 14% among obese patients and 9% among nonobese patients. These associations held even after controlling for age, sex, race, income, and tonsillar hypertrophy.

CONCLUSION

The presence of asthma reduced, whereas obesity increased the likelihood of sOSA among a large cohort of older children referred for PSG. These relationships were additive. Further research is indicated regarding these relationships.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:812-817, 2020.

Asthma is associated with increased probability of needing CPAP in children with severe obstructive sleep apnea

OBJECTIVE

Initiation of continuous positive airway pressure (CPAP) in children with severe obstructive sleep apnea syndrome (OSAS) is challenging and the distinct features of the subset of children requiring CPAP are poorly defined. Asthma often coexists with OSAS in children. The goal of this study was to explore the influence of asthma in the need for CPAP therapy in children with severe OSAS.

HYPOTHESIS

Asthmatic children with severe OSAS have higher probability of needing CPAP than children with severe OSAS without asthma.

METHODS

Cross-sectional study of clinical presentation, individual risk factors, and initial overnight polysomnogram (PSG) parameters in children with severe OSAS. Severe OSAS was defined as an obstructive apnea hypopnea index ≥10/h. The association between asthma and CPAP initiation was studied individually and adjusted by pertinent covariates.

RESULTS

Four hundred eligible children (mean age 7 years, ±SD 5.3) with severe OSAS were enrolled and 133 individuals (33%) were identified to have asthma. The proportion of children needing CPAP was significantly higher in asthmatics with severe OSAS (29%) compared to those with OSAS alone (14%) (P < 0.01). Multivariate analysis demonstrated that the association between asthma and the need of CPAP in pediatric severe OSAS was independent of demographics, OSAS severity, obesity, and history of adenotonsillectomy (P < 0.01).

CONCLUSION

Asthmatic children with severe OSAS have higher probability of needing CPAP independent of relevant covariables. This study further substantiates the link between OSAS and asthma in children and suggests the diagnosis of asthma may influence the need of CPAP therapy for severe OSAS.

Polysomnographic characteristics of adolescents with asthma and low risk for sleep-disordered breathing

PURPOSE

The aim of this study was to describe the polysomnographic characteristics of adolescents with asthma who are at low risk for sleep-disordered breathing (SDB) based on the Pediatric Sleep Questionnaire (PSQ).

METHODS

Overnight polysomnography was performed on 85 adolescents with asthma and a score < 0.33 on the PSQ. The Asthma Control Questionnaire was used to define "well-controlled" versus "inadequately controlled" asthma.

RESULTS

Mean age of participants was 14.5 ± 1.6 years (range, 11 to 17 years), 63.5% were girls, 57.6% were Caucasians, and the mean body mass index percentile was 65.1 ± 26.5. Asthma was well-controlled in 51.7% of the adolescents and inadequately controlled in 15.3%. Mean sleep efficiency (SE) was 88.0 ± 11.1%, and 24.7% had SE < 85%. Mean wakefulness after sleep onset (WASO) was 40.9 ± 44.0 min, and the mean arousal index was 10.8 ± 5.6 per hour. The mean apnea/hypopnea index (AHI) was 2.3 ± 4.2, and 29.4% of participants had SDB (defined by an AHI ≥ 2). Compared with normative values, adolescents with asthma had more nocturnal awakenings and WASO, and less REM sleep. SDB risk was higher in boys [odds ratio = 4.6 (confidence interval 1.4-14.7), p = 0.01]. Asthma control did not impact sleep and respiratory parameters, with no differences found between youth with well-controlled and inadequately controlled asthma.

CONCLUSIONS

Adolescents with asthma are at increased risk of sleep-disordered breathing and suffer from disturbances in sleep continuity with more arousals and sleep fragmentation. Study results highlight the importance of proper screening for sleep-disordered breathing in adolescents with asthma.

Association of common comorbidities with asthma in children: a cross-sectional study

Asthma is a common chronic respiratory disease in children. The diagnosis of asthma in children may be associated with other comorbidities, which may influence the disease in several ways, including optimal asthma control. The main objective of this study was to determine the association of common comorbidities with asthma in children between 5 and 15 years. A cross-sectional study was carried out in a tertiary care hospital of western Rajasthan. A set of 23 questions were offered to the children with asthma and/or their parents and their responses were noted manually. A total of 95 children (74 male) were enrolled, allergic rhinitis (AR) was documented in 72 (75%) followed by psychological disturbance in 68 (71%), snoring in 47 (49.5%), gastro-esophageal reflux disease (GERD) in 44 (46.3%), atopic dermatitis in 26 (27.3%), and sinusitis in 19 (20%) children. There was no statistical significant association observed between asthma comorbidities and gender. Allergic rhinitis was the most common comorbidity in children with asthma followed by psychological disturbance, GER, and snoring. Both boys and girls had similar prevalence of asthma comorbidities.

Validation of the pediatric sleep questionnaire in children with asthma

OBJECTIVE

The prevalence of obstructive sleep apnea (OSA) is higher in children with poorly controlled asthma. We aimed to determine the validity of the Pediatric Sleep Questionnaire (PSQ) to screen for OSA in children with asthma.

METHODS

This retrospective review encompassed sleep studies and medical records of asthmatic children evaluated in the sleep center at CCHMC over 13 years. Measures of validity were calculated using various cut-off values for obstructive apnea-hypopnea index (OI; >1, >2, >5) and PSQ scores (>0.33, >0.5). Correlation between PSQ and OI, PSQ and spirometry, and OI and spirometry was assessed using Spearman's correlation coefficient.

RESULTS

One-hundred and sixty children were included (mean age 11 ± 4 years; 64% males). The mean OI was 4.2 ± 14.3 and the mean PSQ score was 0.57 ± 0.19. Thirty-eight percent of patients had a diagnosis of allergic rhinitis. A total of 70 children (43%) were obese (BMI ≥95th percentile). The correlation between OI and PSQ was statistically significant (r = 0.19, P = 0.015). Using a PSQ cutoff of 0.33, and OI cutoffs of 1, 2, and 5, the sensitivities were 81.6%, 81.6%, and 76.2%, and the specificities were 13.1%, 14.4%, and 14.4%, respectively. When the cutoff for PSQ was raised to 0.5 and using an OI of 1, the sensitivity decreased to 71.1%, but the specificity increased to 36.9%.

CONCLUSIONS

The sensitivity of PSQ in asthmatic children is high and comparable to previous studies, but the specificity is low. The PSQ may be considered a reasonable first-line screening tool for OSA in asthmatic children. Pediatr Pulmonol. 2017;52:382-389. © 2016 Wiley Periodicals, Inc.

Lifestyle Risk Factors for Weight Gain in Children with and without Asthma

A higher proportion of children with asthma are overweight and obese compared to children without asthma; however, it is unknown whether asthmatic children are at increased risk of weight gain due to modifiable lifestyle factors. Thus, the aim of this cross-sectional study was to compare weight-gain risk factors (sleep, appetite, diet, activity) in an opportunistic sample of children with and without asthma. Non-obese children with (n = 17; age 10.7 (2.4) years) and without asthma (n = 17; age 10.8 (2.3) years), referred for overnight polysomnography, underwent measurement of lung function, plasma appetite hormones, dietary intake and food cravings, activity, and daytime sleepiness. Sleep latency (56.6 (25.5) vs. 40.9 (16.9) min, p = 0.042) and plasma triglycerides (1.0 (0.8, 1.2) vs. 0.7 (0.7, 0.8) mmol/L, p = 0.013) were significantly greater in asthmatic versus non-asthmatic children. No group difference was observed in appetite hormones, dietary intake, or activity levels (p > 0.05). Sleep duration paralleled overall diet quality (r = 0.36, p = 0.04), whilst daytime sleepiness paralleled plasma lipids (r = 0.61, p =0.001) and sedentary time (r = 0.39, p = 0.02). Disturbances in sleep quality and plasma triglycerides were evident in non-obese asthmatic children referred for polysomnography, versus non-asthmatic children. Observed associations between diet quality, sedentary behavior, and metabolic and sleep-related outcomes warrant further investigation, particularly the long-term health implications.

Sleep-disordered breathing in children with asthma: a systematic review on the impact of treatment

Background

The objective was to perform a systematic review in order to describe the relationship between asthma and sleep-disordered breathing (SDB) in children, especially regarding the impact of treatment and management.

Methods

We performed an electronic search in MEDLINE, EMBASE, and LILACS database. Study inclusion criteria were the following: 1) studies that examined the relationship between asthma/wheezing and SDB/obstructive sleep apnea (OSA); and 2) studies conducted in children <18 years of age. Primary outcomes were the prevalence of asthma and SDB, the tests used for diagnosis, and the influence of their treatment and management.

Results

One thousand and twenty studies were identified, among which 32 were selected (n=143,343 children; 51% males; age [mean ± standard deviation] 8.4±2.5 years). Most studies (n=26) diagnosed SDB using questionnaires or clinical history. Nine studies performed a sleep study for diagnosing OSA. The diagnosis of asthma was based on clinical history (n=16), previous medical diagnosis (n=4), questionnaires (n=12), and spirometry (n=5). Children with asthma were more likely to develop habitual snoring and OSA, and children with SDB were more likely to develop asthma. Moreover, asthma was associated with more severe OSA, and the presence of SDB was associated with severe asthma. Treatment of SDB with adenotonsillectomy was associated with significant asthma improvement.

Conclusion

The relationship between asthma and SDB appears to be bidirectional, and adenotonsillectomy appears to improve asthma control. Future trials on how asthma treatment could impact on SDB are needed.

Sleep-disordered breathing and asthma: evidence from a large multicentric epidemiological study in China

Background

Previous studies have postulated that sleep-disordered breathing (SDB) may be associated with the occurrence and exacerbation of asthma. However, there was limited quantitative evidence on the topic. This study aimed at investigating the prevalence and predisposing factors of asthma, and quantifying the association between SDB and asthma among school-aged children in China. In addition, a comprehensive meta-analysis of the published evidences and our findings were further conducted.

Methods

To test the hypothesis, we conducted a multicentric cross-sectional study involving 22,478 children aged 5–12 years recruited from eight cities in China. Furthermore, a meta-analysis based on both previously published studies and our cross-sectional study was performed.

Results

The prevalence rate of SDB and asthma was 12.0% and 3.5% among our cross-sectional study sample. It was demonstrated that symptoms of SDB, such as habitual snoring (OR = 1.28, 95%CI: 1.01-1.62), and obstructive sleep apnea (OSA) (OR = 1.92, 95%CI: 1.34-2.76), were significantly associated with asthma, after adjusting for potential confounding factors. In the meta-analysis, SDB was correlated with the prevalence of asthma in both children (OR = 1.58, 95%CI: 1.35-1.80) and adults (OR = 1.55, 95%CI: 1.42-1.67).

Conclusions

Our results provide further evidence for the independent association between SDB and asthma. The clinical significance of our findings lies in the emphasis that children undergoing examination or treatment for asthma should be routinely screened for sleep problems. Further systematic study is required to illuminate the underlying mechanism.

Disparities and genetic risk factors in obstructive sleep apnea

Obstructive sleep apnea (OSA) is an increasingly prevalent condition. A growing body of literature supports substantial racial disparities in the prevalence, risk factors, presentation, diagnosis, and treatment of this disease. Craniofacial structure among Asians appears to confer an elevated risk of OSA despite lower rates of obesity. Among African Americans, Native Americans, and Hispanics, OSA prevalence is increased, likely due in part to obesity. The burden of symptoms, particularly excessive daytime sleepiness, is higher among African Americans, although Hispanics more often report snoring. Limited data suggest that African Americans may be more susceptible to hypertension in the setting of OSA. While differences in genetic risk factors may explain disparities in OSA burden, no definitive genetic differences have yet been identified. In addition to disparities in OSA development, disparities in OSA diagnosis and treatment have also been identified. Increased severity of disease at diagnosis among African Americans suggests a delay in diagnosis. Treatment outcomes are also suboptimal among African Americans. In children, tonsillectomy is less likely to cure OSA and more commonly associated with complications in this group. Among adults, adherence to continuous positive airway pressure (CPAP) is substantially lower in African Americans. The reasons for these disparities, particularly in outcomes, are not well understood and should be a research priority.

Assessment of sleep bruxism, orthodontic treatment need, orofacial dysfunctions and salivary biomarkers in asthmatic children

OBJECTIVE

To evaluate the sleep bruxism, malocclusions, orofacial dysfunctions and salivary levels of cortisol and alpha-amylase in asthmatic children.

DESIGN

108 7-9-yr-old children were selected from Policlinic Santa Teresinha Doutor Antonio Haddad Dib (asthmatics, n=53) and from public schools (controls, n=55), Piracicaba, SP, Brazil. Sleep bruxism diagnosis was confirmed by parental report of grinding sounds and the presence of shiny and polish facets on incisors and/or first permanent molars. The index of orthodontic treatment need was used for occlusion evaluation. Orofacial dysfunctions were evaluated using the nordic orofacial test-screening (NOT-S). Salivary cortisol and alpha-amylase were expressed as "awakening response" (AR), calculated as the difference between levels immediately after awakening and 30 min after waking, and "diurnal decline" (DD), calculated as the difference between levels at 30 min after waking and at bedtime. Data were analyzed using Shapiro-Wilk/Kolmogorov-Smirnov, Chi-square, unpaired t test/Mann-Whitney and paired t/Wilcoxon tests.

RESULTS

Sleep bruxism was more prevalent in children with asthma than controls (47.2% vs. 27.3%, p<0.05). Asthmatics had higher scores of NOT-S total and interview (p<0.05). Dysfunctions on sensory function and chewing and swallowing were more frequent in asthmatics (p<0.05). Salivary cortisol AR on weekend was significantly higher for asthmatics (p<0.05). Salivary cortisol DD was significantly higher on weekday than weekend for controls (p<0.05). There were no significant differences in alpha-amylase values in and between groups.

CONCLUSIONS

The presence of asthma in children was associated with sleep bruxism, negative perception of sensory, chewing and swallowing functions, and higher concentrations of salivary cortisol on weekend.

Poor sleep quality measured by polysomnography in non-obese asthmatic children with or without moderate to severe obstructive sleep apnea

BACKGROUND

The co-effect of asthma and obstructive sleep apnea (OSA) on sleep quality among children remained unclear.

OBJECTIVE

To compare sleep quality and emotional/behavioral problems among asthmatic and non-asthmatic children with or without moderate to severe obstructive sleep apnea.

METHOD

An AHI-range-matched BMI-range-matched cross-sectional design was used to examine polysomnographic evaluation and emotional/behavioral problems in 102 non-obese children aged between 6 and 12 years old, categorized as with or without asthma and sleep disordered breathing.

RESULTS

Asthmatic children in AHI ≤ 5/h group revealed a significantly longer sleep latency, a greater leg movement index (LMI), and a lower ratio of slow wave sleep compared with non-asthmatic AHI ≤ 5/h group. Compared with non-asthmatic AHI > 5/h group, asthmatic children displayed a higher ratio of REM sleep, sleep stage 1 and 2, a lower ratio of slow wave sleep, as well as a greater respiratory arousal index and LMI. There was no significant difference in emotional/behavior problems among groups.

CONCLUSION

Sleep disturbance exists in asthmatic children with or without moderate to severe obstructive sleep apnea. Non-obese asthmatic children had less slow wave sleep compared with non-asthmatic children. We might recommend that sleep quality could be noticed and evaluated in children with asthma.

Alterations in circulating T-cell lymphocyte populations in children with obstructive sleep apnea

STUDY OBJECTIVES

Changes in lymphocyte phenotype and functionality have been described in adult patients with obstructive sleep apnea (OSA). We hypothesized that OSA is associated with T lymphocyte alterations in children, particularly in T regulatory lymphocytes (T regs), and aimed to characterize circulating T lymphocyte subsets in children with OSA.

DESIGN

Cross-sectional.

SETTING

Kosair Children's Hospital (Louisville, KY, USA) and Comer Children's Hospital (Chicago, IL, USA).

PARTICIPANTS

Consecutively recruited children being evaluated for habitual snoring.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Overnight polysomnography (PSG) was performed and a fasting blood sample was obtained from the patients. Flow cytometry was performed on peripheral blood mononuclear cells stained for CD3, CD4, CD8, CD25, FOXP3, interleukin-4 (IL-4), interferon-γ (IFN-γ), and IL-17. Patients were divided into three groups based on their PSG: controls (apnea-hypopnea indices [AHI] < 1/h total sleep time [TST]), mild OSA (1 ≤ AHI < 5/hTST), moderate-severe OSA (AHI ≥ 5/h TST). The percentage of CD4+ and T reg lymphocytes differed across groups. Children with moderate-severe OSA had significantly reduced T reg than control children (median [interquartile range] 4.8 [3.8-5.7% CD4+] versus 7.8 [7.0-9.2% CD4+]; P < 0.001). There were also significant differences in the percentage of T helper 1 (Th1) lymphocytes and in Th1:Th2 ratios between groups. Children with moderate-severe OSA had increased Th1 cells (P = 0.001) and Th1:Th2 ratios (P = 0.0026) compared with children with mild OSA and control children. Associations between AHI and T reg (P = 0.0003; r = -0.46), CD4+ lymphocytes (P = 0.0047; r = -0.37), and Th1:Th2 ratios (P = 0.0009; r = 0.43) emerged. In addition, the percentage of T reg was inversely correlated with Th1:Th2 ratios (P = 0.029; r = -0.29).

CONCLUSIONS

Pediatric OSA is associated with reduced T reg population and altered Th1:Th2 balance toward Th1 predominance, suggesting a shift to a proinflammatory state. The changes in lymphocytic phenotypes associated with OSA may contribute to the variance in systemic inflammation and downstream morbidities associated with this condition.

Increased sleep latency and reduced sleep duration in children with asthma

STUDY OBJECTIVE

Sleep disturbance is reported to be more prevalent in children and adolescents with asthma than those without. However, this has not been described adequately using objective measures. The aim of this study was to objectively characterise sleep disturbance in asthmatic and non-asthmatic children and adolescents.

METHODS

A retrospective analysis of polysomnography recordings from children aged 5-17 years old, with (n = 113) and without asthma (n = 104), referred for a sleep study over the period 2005-2010 at the Paediatric Sleep Unit, John Hunter Children's Hospital in Newcastle, NSW Australia, was carried out.

RESULTS

Polysomnographic recordings were analysed to compare sleep quality and quantity between asthmatic and non-asthmatic children. Sleep latency was significantly longer in asthmatic children compared to controls. However, this result was significant for females only (46.2 (5.6) vs 33.2 (2.7) min, p < 0.05). Male asthmatics had significantly shorter sleep duration (425.9 (5.4) vs 441.8 (5.4) min, p < 0.05) than male controls.

CONCLUSIONS

Sleep disturbance exists in children with asthma and manifests differently in males and females. Further investigation into the clinical implication of increased sleep latency and reduced sleep duration upon daytime functioning and lifestyle behaviours in children and adolescents with asthma is warranted.

Obstructive sleep apnea in poorly controlled asthmatic children: effect of adenotonsillectomy

BACKGROUND

Asthma and obstructive sleep apnea (OSA) in children share multiple epidemiological risk factors and the prevalence of snoring is higher in asthmatic children, suggesting that the latter may be at increased risk for OSA. Since both asthma and OSA are inflammatory disorders, we hypothesized that polysomnographically demonstrated OSA would be more frequent among poorly controlled asthmatics (PCA), and that treatment of OSA, if present, would ameliorate the frequency of acute asthmatic exacerbations (AAE).

METHODS

Children with PCA were referred for an overnight sleep study, and adenotonsillectomy (tonsillectomy and adenoidectomy, T&A) was performed if OSA was present. Frequency of asthma symptoms and exacerbations were compared.

RESULTS

Ninety-two PCA children, ages 3-10 years, with a mean frequency of AAE of 3.4 ± 0.4/year were prospectively referred for a sleep study. OSA (i.e., AHI > 5/hrTST) was present in 58 patients (63.0%; OR: 40.9, 12.9-144.1, P < 0.000001 compared to the prevalence of OSA in a non-asthmatic population). Information at 1-year follow-up was available for 35 PCA children after T&A. The annual frequency of AAE, rescue inhaled use, and asthma symptoms in this sub-group decreased compared to no changes in the group without OSA.

CONCLUSIONS

The prevalence of OSA is markedly increased among PCA children and treatment of OSA appears to be associated with substantial improvements in the severity of the underlying asthmatic condition.

Polysomnography and actigraphy concordance in juvenile idiopathic arthritis, asthma and healthy children

The aims of this study were to evaluate sensitivity, specificity and accuracy with an epoch-by-epoch comparison of polysomnography (PSG) and actigraphy with activity counts scored at low, medium and high thresholds, and to compare PSG-derived total sleep time (TST), sleep efficiency (SE) and wake after sleep onset (WASO) to the same variables derived from actigraphy at low, medium and high thresholds in 9- to 11-year-old children with juvenile idiopathic arthritis (JIA), asthma and healthy control children. One night of PSG and actigraphy were recorded. Pairwise group comparisons for sensitivity showed significant differences at the low [Tukey's honest significant difference (HSD) P < 0.002], medium (P < 0.001) and high thresholds (P < 0.001) between JIA and asthma groups, and at the high threshold between JIA and controls (P < 0.009). Significant differences were found for specificity at the low (P < 0.001), medium (P < 0.001) and high thresholds (P < 0.001) between JIA and asthma groups, and between JIA and controls (low, P < 0.002: medium, P < 0.002: high, P < 0.008 threshold). PSG TST, WASO and SE were not significantly different among the groups, but significant group differences were found for actigraphy TST, WASO and SE at all three thresholds. Actigraphy showed the least overestimation or underestimation of sleep or wakefulness at the medium threshold for TST and WASO for all three groups. Compared to PSG, actigraphy was most accurate in the identification of sleep from wakefulness in 9- to 11-year-old healthy children, and less accurate in children with JIA and asthma.

Executive summary of respiratory indications for polysomnography in children: an evidence-based review

OBJECTIVE

This comprehensive, evidence-based review provides a systematic analysis of the literature regarding the validity, reliability, and clinical utility of polysomnography for characterizing breathing during sleep in children. Findings serve as the foundation of practice parameters regarding respiratory indications for polysomnography in children.

METHODS

A task force of content experts performed a systematic review of the relevant literature and graded the evidence using a standardized grading system. Two hundred forty-three evidentiary papers were reviewed, summarized, and graded. The analysis addressed the operating characteristics of polysomnography as a diagnostic procedure in children and identified strengths and limitations of polysomnography for evaluation of respiratory function during sleep.

RESULTS

The analysis documents strong face validity and content validity, moderately strong convergent validity when comparing respiratory findings with a variety of relevant independent measures, moderate-to-strong test-retest validity, and limited data supporting discriminant validity for characterizing breathing during sleep in children. The analysis documents moderate-to-strong test-retest reliability and interscorer reliability based on limited data. The data indicate particularly strong clinical utility in children with suspected sleep related breathing disorders and obesity, evolving metabolic syndrome, neurological, neurodevelopmental, or genetic disorders, and children with craniofacial syndromes. Specific consideration was given to clinical utility of polysomnography prior to adenotonsillectomy (AT) for confirmation of obstructive sleep apnea syndrome. The most relevant findings include: (1) recognition that clinical history and examination are often poor predictors of respiratory polygraphic findings, (2) preoperative polysomnography is helpful in predicting risk for perioperative complications, and (3) preoperative polysomnography is often helpful in predicting persistence of obstructive sleep apnea syndrome in patients after AT. No prospective studies were identified that address whether clinical outcome following AT for treatment of obstructive sleep apnea is improved in association with routine performance of polysomnography before surgery in otherwise healthy children. A small group of papers confirm the clinical utility of polysomnography for initiation and titration of positive airway pressure support.

CONCLUSIONS

Pediatric polysomnography shows validity, reliability, and clinical utility that is commensurate with most other routinely employed diagnostic clinical tools or procedures. Findings indicate that the "gold standard" for diagnosis of sleep related breathing disorders in children is not polysomnography alone, but rather the skillful integration of clinical and polygraphic findings by a knowledgeable sleep specialist. Future developments will provide more sophisticated methods for data collection and analysis, but integration of polysomnographic findings with the clinical evaluation will represent the fundamental diagnostic challenge for the sleep specialist.

Practice parameters for the respiratory indications for polysomnography in children

BACKGROUND

There has been marked expansion in the literature and practice of pediatric sleep medicine; however, no recent evidence-based practice parameters have been reported. These practice parameters are the first of 2 papers that assess indications for polysomnography in children. This paper addresses indications for polysomnography in children with suspected sleep related breathing disorders. These recommendations were reviewed and approved by the Board of Directors of the American Academy of Sleep Medicine.

METHODS

A systematic review of the literature was performed, and the American Academy of Neurology grading system was used to assess the quality of evidence. RECOMMENDATIONS FOR PSG USE: 1. Polysomnography in children should be performed and interpreted in accordance with the recommendations of the AASM Manual for the Scoring of Sleep and Associated Events. (Standard) 2. Polysomnography is indicated when the clinical assessment suggests the diagnosis of obstructive sleep apnea syndrome (OSAS) in children. (Standard) 3. Children with mild OSAS preoperatively should have clinical evaluation following adenotonsillectomy to assess for residual symptoms. If there are residual symptoms of OSAS, polysomnography should be performed. (Standard) 4. Polysomnography is indicated following adenotonsillectomy to assess for residual OSAS in children with preoperative evidence for moderate to severe OSAS, obesity, craniofacial anomalies that obstruct the upper airway, and neurologic disorders (e.g., Down syndrome, Prader-Willi syndrome, and myelomeningocele). (Standard) 5. Polysomnography is indicated for positive airway pressure (PAP) titration in children with obstructive sleep apnea syndrome. (Standard) 6. Polysomnography is indicated when the clinical assessment suggests the diagnosis of congenital central alveolar hypoventilation syndrome or sleep related hypoventilation due to neuromuscular disorders or chest wall deformities. It is indicated in selected cases of primary sleep apnea of infancy. (Guideline) 7. Polysomnography is indicated when there is clinical evidence of a sleep related breathing disorder in infants who have experienced an apparent life-threatening event (ALTE). (Guideline) 8. Polysomnography is indicated in children being considered for adenotonsillectomy to treat obstructive sleep apnea syndrome. (Guideline) 9. Follow-up PSG in children on chronic PAP support is indicated to determine whether pressure requirements have changed as a result of the child's growth and development, if symptoms recur while on PAP, or if additional or alternate treatment is instituted. (Guideline) 10. Polysomnography is indicated after treatment of children for OSAS with rapid maxillary expansion to assess for the level of residual disease and to determine whether additional treatment is necessary. (Option) 11. Children with OSAS treated with an oral appliance should have clinical follow-up and polysomnography to assess response to treatment. (Option) 12. Polysomnography is indicated for noninvasive positive pressure ventilation (NIPPV) titration in children with other sleep related breathing disorders. (Option) 13. Children treated with mechanical ventilation may benefit from periodic evaluation with polysomnography to adjust ventilator settings. (Option) 14. Children treated with tracheostomy for sleep related breathing disorders benefit from polysomnography as part of the evaluation prior to decannulation. These children should be followed clinically after decannulation to assess for recurrence of symptoms of sleep related breathing disorders. (Option) 15. Polysomnography is indicated in the following respiratory disorders only if there is a clinical suspicion for an accompanying sleep related breathing disorder: chronic asthma, cystic fibrosis, pulmonary hypertension, bronchopulmonary dysplasia, or chest wall abnormality such as kyphoscoliosis. (Option) RECOMMENDATIONS AGAINST PSG USE: 16. Nap (abbreviated) polysomnography is not recommended for the evaluation of obstructive sleep apnea syndrome in children. (Option) 17. Children considered for treatment with supplemental oxygen do not routinely require polysomnography for management of oxygen therapy. (Option)

CONCLUSIONS

Current evidence in the field of pediatric sleep medicine indicates that PSG has clinical utility in the diagnosis and management of sleep related breathing disorders. The accurate diagnosis of SRBD in the pediatric population is best accomplished by integration of polysomnographic findings with clinical evaluation.

Obstructive airway disease and obstructive sleep apnea: effect of pulmonary function

This study sought to determine whether reduced pulmonary function in obstructive airway disease (OAD) is an independent risk factor for obstructive sleep apnea (OSA). This was a prospective observational study conducted at an outpatient pulmonary clinic. Adults with a known diagnosis of COPD/asthma were enrolled as OAD group. Family members without a history of COPD/asthma who accompanied these patients to the clinic were enrolled as a control group. The Berlin Questionnaire (BQ) was used to assess OSA risk in the OAD group and controls. Forced expiratory volume in 1 second (FEV(1) % predicted) was determined from spirometry. The subjects at high risk for OSA were referred for a full overnight polysomnogram (PSG). The prevalence of patients with a high risk of OSA was 55.2% in the OAD group, which was higher than in the controls (7.5%, p < 0.0001). OAD subjects had a higher body mass index (BMI) and larger neck circumference than controls (p < 0.01). There was no difference in FEV(1) % predicted between the OAD patients at high risk and low risk of OSA. On receiver operator curve (ROC) analysis, FEV(1) % predicted was not a significant predictor of high OSA risk. Using logistic regression, FEV(1) % predicted had no association with OSA risk. There was no correlation between FEV(1) % predicted and total apnea-hypopnea index (AHI), oxygen desaturation index, % time spent below oxygen saturation 90%, and mean oxygen saturation on multiple regression analysis. OSA appears to be common in patients with COPD or asthma in an urban outpatient pulmonary clinic. However, the high prevalence of OSA in OAD patients appears to be due to obesity, and reduced pulmonary function is not an independent risk factor for OSA.

Role of adenoidectomy in otitis media and respiratory function

Adenoidectomy is among the most frequent surgical procedures performed on children. The rationale for adenoidectomy is to remove a chronically infected or enlarged and obstructing adenoid. Adenoidectomies are performed on children who have recurrent or chronic otitis media with effusion, on children with chronic rhinosinusitis, and on children with nasopharyngeal obstruction causing sleep disturbances and continuous mouth breathing. Various underlying factors that lead to adenoidectomy are also associated with asthma. Asthma is associated with recurrent respiratory tract infections predisposing individuals to recurrent or chronic otitis media and chronic rhinosinusitis. Children with asthma also have an increased risk of sleep-disordered breathing that is treated with adenoidectomy in the presence of nasopharyngeal obstruction. In nonasthmatic children, adenoidectomy does not influence the development of IgE-mediated allergy, bronchial hyperreactivity, or exhaled nitric oxide concentrations, all of which are surrogate asthma markers. Adenoidectomy in selected asthmatic children may relieve comorbidities associated with asthma.

Elevated economic burden in obstructive lung disease patients with concomitant sleep apnea syndrome

PURPOSE

The purpose of this study is to examine the incremental economic burden of sleep apnea syndrome (SAS) among individuals with concomitant asthma, chronic obstructive pulmonary disease (COPD), or both (i.e., asthma/COPD).

METHODS

Maryland Medicaid claims data were used to identify beneficiaries with asthma (n = 3,072), COPD (n = 3,455), or both (n = 2,604). We compared patient's baseline characteristics by SAS and stratified the analyses by disease cohort to examine the effect of SAS on medical utilization and cost.

RESULTS

SAS was more prevalent among beneficiaries with asthma/COPD (6.72%) than beneficiaries with COPD alone (2.87%) or asthma alone (2.15%). Asthma/COPD and COPD beneficiaries with SAS had more medical service claims (p < 0.001) and higher medical cost than beneficiaries without SAS: $5,773 and $4,155 in excess costs among asthma/COPD (p = 0.037) and COPD patients (p = 0.035), respectively. Medical utilization and cost did not differ by SAS in asthma patients (p = 0.567).

CONCLUSIONS

SAS may add additional economic burden on beneficiaries who already have COPD or asthma/COPD.

Body mass index-percentile and diagnostic accuracy of childhood asthma

OBJECTIVE

To determine whether high BMI-percentile is associated with misdiagnosis of asthma among children referred to an asthma specialist.

METHODS

We queried the electronic records of children 8 to 18 years of age seen by a Nemours pediatric pulmonologist. All visits during a 6-year period with the chief complaint of asthma, or an asthma-like symptom such as wheeze, cough, or dyspnea, were included. We collected spirometry, blood counts, and immunoglobulin E (IgE) if available. We determined whether the child had referring physician-diagnosed asthma, specialist-diagnosed asthma, or both. Specialist-diagnosed asthmatics who met additional objective "gold-standard" criterion were labeled strict-criterion asthma.

RESULTS

Prevalence of high BMI-percentile was extremely common in all defined asthma groups, even those meeting strict criteria for diagnosis. Referring physician-diagnosed asthmatics did not have higher rates of obesity, and referring physician-diagnosed asthmatics had objective indicators of asthma that were the same as asthmatics diagnosed by a specialist. There was good diagnostic correlation between referring physicians and asthma specialists that was not affected by BMI. Among specialist-diagnosed asthmatics, increased BMI-percentile associated with significantly reduced forced expiratory volume in 1 second (FEV(1)), forced expiratory flow during the middle half of the forced vital capacity (FEF(25 - 75)), and FEV(1)/forced vital capacity (FVC); and significantly increased total blood leukocytes, neutrophils, and platelets compared to leans. For all 2,258 referrals, the estimated odds ratio of receiving a specialist-diagnosis of asthma increased by 0.4% with each increasing BMI percentile.

CONCLUSIONS

Referring physicians do not appear to erroneously diagnose children with asthma due to overweight status. Our data confirm that overweight status is extremely high in children with true asthma and likely increases the risk for true asthma. Although these data cannot discern causality, high BMI-percentile is associated with greater airflow obstruction and elevated markers of systemic inflammation that could contribute to underlying mechanisms of asthma.