Sibling risk of pediatric obstructive sleep apnea syndrome and adenotonsillar hypertrophy

Siblings' Risk of Adenoid Hypertrophy: A Cohort Study in Children

BACKGROUND

The aim of this study was to compare adenoid size in preschool-age siblings using flexible nasopharyngoscopy examination (FNE) when they reach the same age. The occurrence of adenoid symptoms in these patients was also analyzed. This study was conducted to analyze the adenoid size in siblings when they reach the same age and substantiate a correlation between adenoid hypertrophy (AH) and adenoid symptoms.

METHODS

We analyzed and reported on the symptoms, ENT examination results, and FNE of 49 pairs of siblings who were examined at the same age.

RESULTS

There was a strong association in adenoid size between siblings when they are at a similar age (r = 0.673, p < 0.001). Second-born children whose older sibling had IIIo AH (A/C ratio > 65%) had a risk of IIIo AH 26 times greater than patients whose older sibling did not have IIIo AH (OR = 26.30, 95% CI = 2.82-245.54). Over 90% of snoring children whose siblings had confirmed IIIo AH would develop IIIo AH by the time they reach the same age. Second-born children in whom snoring occurs and whose older siblings have a IIIo AH have about a 46 times higher risk of IIIo AH compared to patients who did not meet these two conditions (p < 0.001, OR = 46.67, 95% CI = 8.37-260.30).

CONCLUSIONS

A significant familial correlation between adenoid size in siblings when they reach the same age was shown. If the older sibling has a confirmed overgrown adenoid (IIIo AH) and their younger sibling presents adenoid symptoms, particularly snoring, it is highly probable that they will also have an overgrown adenoid.

Analysis of the Risk Factors Associated With Obstructive Sleep Apnea Syndrome in Chinese Children

Objective

The present study was developed to explore risk factors related to the incidence and severity of obstructive sleep apnea syndrome (OSAS) in children.

Methods

The present study enrolled pediatric patients who admitted to our department for snoring and/or open-mouth breathing. All children completed a questionnaire and underwent physical examination and polysomnography (PSG). The cases were separated into OSAS and primary snoring (PS) groups. Factors associated with these two groups were analyzed, with risk factors significantly associated with OSAS then being identified through logistic regression analyses. OSAS was further subdivided into mild, moderate, and severe subgroups, with correlations between risk factors and OSAS severity then being analyzed.

Results

In total, 1,550 children were included in the present study, of which 852 and 698 were enrolled in the OSAS and PS groups. In univariate analyses, obesity, family passive smoking, a family history of snoring, allergic rhinitis, asthma, adenoid hypertrophy, and tonsil hypertrophy were all related to pediatric OSAS (P < 0.05). In a multivariate logistic regression analysis, adenoid hypertrophy (OR:1.835, 95% CI: 1.482-2.271) and tonsil hypertrophy (OR:1.283, 95% CI:1.014-1.622) were independently associated with the risk of pediatric OSAS (P < 0.05). Stratification analyses revealed that OSAS incidence increased in a stepwise manner with increases in adenoid and tonsil grading (P < 0.01). Correlation analyses revealed that adenoid hypertrophy and tonsilar hypertrophy were not significantly associated with OSAS severity (r = 0.253, 0.069, respectively, P < 0.05), and tonsil and adenoid size were no correlation with obstructive apnea-hypopnea index (OAHI) (r = 0.237,0.193, respectively, P < 0.001).

Conclusion

Obesity, family passive smoking, a family history of snoring, allergic rhinitis, asthma, tonsil hypertrophy, and adenoid hypertrophy may be potential risk factors for pediatric OSAS. Adenoid hypertrophy and tonsil hypertrophy were independently related to the risk of pediatric OSAS, with OSAS incidence increasing with the size of the adenoid and tonsil, while the severity of OSAS is not parallel related to the adenoid or tonsil size.

Obstructive sleep apnea and associated factors among hypertensive patients attending a tertiary cardiac center in Tanzania: a comparative cross-sectional study

Background

There is mounting evidence for a reciprocal yet bidirectional association between sleep-disordered breathing and hypertension. Obstructive sleep apnea (OSA), a common cause of systemic hypertension is an independent risk factor for hypertension-related cardiovascular morbidity and mortality. In this comparative hospital-based cross-sectional study, we sought to explore the burden of obstructive sleep apnea and its associated risk factors among hypertensive patients attending Jakaya Kikwete Cardiac Institute.

Methodology

A total of 1974 individuals (i.e. 1289 hypertensive and 685 normotensives) were consecutively enrolled in this study. The Berlin questionnaire and Epworth Sleepiness Scale were utilized in the assessment of OSA and excessive daytime sleepiness (EDS) respectively. Logistic regression analyses were employed in the determination of associated factors for OSA.

Results

The mean age was 53.4 years and females constituted the large majority (60.4%) of participants. About three quarters (74.1%) of participants had excess body weight, 11.6% had diabetes, 8.0% had asthma and 18.6% had history of recurrent nasal congestion. Positive family history of snoring was reported by 43.1% of participants and 36.9% had a personal history of snoring. Persons with hypertension displayed a higher frequency (42.1%) of OSA compared to their normotensive counterparts (11.8%), p < 0.001. Multivariate logistic regression analyses revealed hypertension (OR 5.1, 95% CI 3.2-8.2, p < 0.001), diabetes mellitus (OR 2.2, 95% CI 1.3-3.5, p < 0.01), chronic nasal congestion (OR 1.6, 95% CI 1.1-2.5, p = 0.01), obesity (OR 2.4, 95% CI 1.8-3.3, p < 0.001), increased neck circumference (OR 2.7, 95% CI 1.2-6.4, p = 0.02), family history of snoring (OR 5.5, 95% CI 4.0-7.5, p < 0.001), and working > 8 h/24 h (OR 0.6, 95% CI 0.4-1.0, p = 0.03) to have an independent association for OSA. Furthermore, participants with hypertension displayed superior odds for OSA compared to their normotensive counterparts across all subgroup analyses.

Conclusion

OSA is considerably common among patients with hypertension in a tertiary health care setting in Tanzania. Positive family history of snoring was the strongest associated factor; however, excess body weight proved to be the strongest modifiable risk factor. In view of its pervasiveness, OSA should be an integral part of the medical evaluation in hypertensive individuals.

Intermediate phenotypes of childhood obstructive sleep apnea

An intermediate phenotype of a disease is a trait in the path of pathogenesis from genetic predisposition to disease manifestation. Identifying intermediate phenotypes with high heritability is helpful in delineating the genetics of a disorder. In this study, we aimed to examine various traits with regards to obesity, cardiovascular risk and upper airway structure to identify potential intermediate phenotypes of childhood obstructive sleep apnea (OSA). Children aged between 6 and 18 years and their parents and siblings were recruited. All subjects underwent anthropometric measurements, cardiovascular risk assessment, sonographic measurement of lateral parapharyngeal wall (LPW) thickness, X-ray cephalometry and overnight polysomnography. A total of 34 phenotypes were examined. One hundred and one families consisting of 127 children (46 overweight) and 198 adults (84 overweight) were recruited. Heritability of obstructive apnea-hypopnea index (OAHI) was significant in overweight (h²  = 0.54) but not normal-weight individuals (h²  = 0.12). LPW thickness (h²  = 0.68) and resting blood pressure (h²  = 0.36 and 0.43 for systolic blood pressure [SBP] and diastolic blood pressure [DBP], respectively) were significantly heritable and associated with OAHI. Moreover, these traits were found to have shared genetic variance with OAHI in the overweight subgroup. Hyoid bone position also had significant heritability (h²  = 0.55) and association with OAHI but genetic correlation with OSA severity was not demonstrated. These findings suggest that LPW thickness and resting blood pressure are possible intermediate phenotypes of OSA independent of body mass index, especially in overweight patients. Identifying genes relevant to these phenotypes may help to elucidate the genetic susceptibility of OSA.

Preterm birth and risk of sleep-disordered breathing from childhood into mid-adulthood

BACKGROUND

Preterm birth (gestational age <37 weeks) has previously been associated with cardiometabolic and neuropsychiatric disorders into adulthood, but has seldom been examined in relation to sleep disorders. We conducted the first population-based study of preterm birth in relation to sleep-disordered breathing (SDB) from childhood into mid-adulthood.

METHODS

A national cohort study was conducted of all 4 186 615 singleton live births in Sweden during 1973-2014, who were followed for SDB ascertained from nationwide inpatient and outpatient diagnoses through 2015 (maximum age 43 years). Cox regression was used to examine gestational age at birth in relation to SDB while adjusting for other perinatal and maternal factors, and co-sibling analyses assessed for potential confounding by unmeasured shared familial factors.

RESULTS

There were 171 100 (4.1%) persons diagnosed with SDB in 86.0 million person-years of follow-up. Preterm birth was associated with increased risk of SDB from childhood into mid-adulthood, relative to full-term birth (39-41 weeks) [adjusted hazard ratio (aHR), ages 0-43 years: 1.43; 95% confidence interval (CI), 1.40, 1.46; P <0.001; ages 30-43 years: 1.40; 95% CI, 1.34, 1.47; P <0.001]. Persons born extremely preterm (<28 weeks) had more than 2-fold risks (aHR, ages 0-43 years: 2.63; 95% CI, 2.41, 2.87; P <0.001; ages 30-43 years: 2.22; 95% CI, 1.64, 3.01; P <0.001). These associations affected both males and females, but accounted for more SDB cases among males (additive interaction, P = 0.003). Co-sibling analyses suggested that these findings were only partly due to shared genetic or environmental factors in families.

CONCLUSIONS

Preterm-born children and adults need long-term follow-up for anticipatory screening and potential treatment of SDB.

Familial Aggregation and Heritability of Obstructive Sleep Apnea Using Children Probands

STUDY OBJECTIVES

Previous studies suggest the presence of familial aggregation of obstructive sleep apnea (OSA) in adults. However, similar data on childhood OSA are limited. This family study aimed to investigate the heritability and familial aggregation of childhood OSA and to examine whether significant differences existed between patients of normal weight and overweight.

METHODS

Children aged 6 to 18 years were recruited as probands either from attendants to sleep clinic (with habitual snoring) or the community (without habitual snoring). Parents and siblings of the probands were also invited to participate. All participants underwent nocturnal sleep study.

RESULTS

A total of 229 probands took part, of whom 33 had moderate to severe OSA, 70 had mild disease, and 126 had no OSA. A total of 412 relatives were also recruited. Although the overall heritability of obstructive apnea-hypopnea index (OAHI) was not significant (h² ± SE = 0.03 ± 0.09, P = .37), it was significant in overweight individuals on subgroup analysis (h² ± SE = 0.43 ± 0.24, P = .032). Significant interaction effect of overweight was demonstrated in both heritability and familial aggregation analyses. Bivariate genetic analysis found that the genetic correlation between OAHI and body mass index in overweight individuals (ρg ± SE = 0.63 ± 0.18) was significantly different from both 0 (P = .005) and 1 (P = .025).

CONCLUSIONS

The differential results of heritability and familial aggregation of OSA in normal weight and overweight subgroups substantiated the recommendation of separating childhood OSA into normal weight and overweight subtypes. In the overweight subgroup, there may be obesity-independent components involved in the genetic variance of OAHI, although a significant proportion of the genetic variance is shared with obesity.

How do we recognize the child with OSAS?

Obstructive sleep-disordered breathing includes a spectrum of clinical entities with variable severity ranging from primary snoring to obstructive sleep apnea syndrome (OSAS). The clinical suspicion for OSAS is most often raised by parental report of specific symptoms and/or abnormalities identified by the physical examination which predispose to upper airway obstruction (e.g., adenotonsillar hypertrophy, obesity, craniofacial abnormalities, neuromuscular disorders). Symptoms and signs of OSAS are classified into those directly related to the intermittent pharyngeal airway obstruction (e.g., parental report of snoring, apneic events) and into morbidity resulting from the upper airway obstruction (e.g., increased daytime sleepiness, hyperactivity, poor school performance, inadequate somatic growth rate or enuresis). History of premature birth and a family history of OSAS as well as obesity and African American ethnicity are associated with increased risk of sleep-disordered breathing in childhood. Polysomnography is the gold standard method for the diagnosis of OSAS but may not be always feasible, especially in low-income countries or non-tertiary hospitals. Nocturnal oximetry and/or sleep questionnaires may be used to identify the child at high risk of OSAS when polysomnography is not an option. Endoscopy and MRI of the upper airway may help to identify the level(s) of upper airway obstruction and to evaluate the dynamic mechanics of the upper airway, especially in children with combined abnormalities. Pediatr Pulmonol. 2017;52:260-271. © 2016 Wiley Periodicals, Inc.

Obstructive sleep disordered breathing in 2- to 18-year-old children: diagnosis and management

This document summarises the conclusions of a European Respiratory Society Task Force on the diagnosis and management of obstructive sleep disordered breathing (SDB) in childhood and refers to children aged 2-18 years. Prospective cohort studies describing the natural history of SDB or randomised, double-blind, placebo-controlled trials regarding its management are scarce. Selected evidence (362 articles) can be consolidated into seven management steps. SDB is suspected when symptoms or abnormalities related to upper airway obstruction are present (step 1). Central nervous or cardiovascular system morbidity, growth failure or enuresis and predictors of SDB persistence in the long-term are recognised (steps 2 and 3), and SDB severity is determined objectively preferably using polysomnography (step 4). Children with an apnoea-hypopnoea index (AHI) >5 episodes·h(-1), those with an AHI of 1-5 episodes·h(-1) and the presence of morbidity or factors predicting SDB persistence, and children with complex conditions (e.g. Down syndrome and Prader-Willi syndrome) all appear to benefit from treatment (step 5). Treatment interventions are usually implemented in a stepwise fashion addressing all abnormalities that predispose to SDB (step 6) with re-evaluation after each intervention to detect residual disease and to determine the need for additional treatment (step 7).

Parental history of adenotonsillectomy is associated with obstructive sleep apnea severity in children with snoring

OBJECTIVE

To test the hypothesis that history of adenoidectomy and/or tonsillectomy (AT) in at least 1 of the parents during childhood, is a risk factor for moderate-to-severe obstructive sleep apnea (OSA) (apnea-hypopnea index [AHI] >5 episodes/hour) in the offspring with snoring.

STUDY DESIGN

Data of children with snoring who were referred for polysomnography over 12 years by primary care physicians were reviewed.

RESULTS

Data of 798 children without history of prior AT, neuromuscular, or genetic disorders or craniofacial abnormalities were analyzed. Of these children, 69.3% had tonsillar hypertrophy, 25.8% were obese, 26.8% had at least 1 parent with history of AT, and 22.1% had AHI >5 episodes/hour. Parental history of AT was significantly associated with moderate-to-severe OSA (logit model including sex, tonsillar hypertrophy, obesity, and physician-diagnosed wheezing; OR [95% CI], 1.70 [1.18-2.46]; P < .01). When significant variables from the logit model (tonsillar hypertrophy, obesity, parental history of AT) were considered independently or in combination, tonsillar hypertrophy combined with history of AT in at least 1 of the parents had high specificity (84.4%) and the highest positive likelihood ratio (1.78) for identifying children with AHI >5 episodes/hour.

CONCLUSIONS

Among children with snoring who are referred for polysomnography by primary care physicians, those with tonsillar hypertrophy and parental history of AT have increased risk of moderate-to-severe OSA and represent 1 of the subgroups that should be prioritized for a sleep study in settings with limited resources.

Family history of adenotonsillectomy as a risk factor for tonsillar hypertrophy and snoring in childhood

OBJECTIVE

Accumulating evidence supports a role for familial predisposition in the pathogenesis of OSA. In this study, it was hypothesized that parental history of adenoidectomy and/or tonsillectomy (AT), which is the standard treatment for pediatric OSA is a risk factor for tonsillar hypertrophy and habitual snoring (>3 nights/week) in the offspring.

METHODS

Children were recruited from the emergency department and the pediatric pulmonology clinic. Paternal or maternal history of AT (explanatory variables) and habitual snoring (outcome) were recorded and presence of tonsillar hypertrophy (outcome) was assessed.

RESULTS

Two hundred ninety-two children (2-14 y.o.) were recruited; 37 (12.7%) of them had paternal history of AT, 39 (13.4%) maternal history of AT, 60 (20.5%) tonsillar hypertrophy, and 48 (16.4%) habitual snoring. Maternal and paternal history of AT were significantly associated with the presence of tonsillar hypertrophy even after adjustment for age, gender, obesity, passive smoking, and physician-diagnosed wheezing requiring treatment with inhaled medications over the past year [odds ratios (95% confidence interval): 3.52 (1.54-8.06); P < 0.01 and 4.70 (2.13-10.36); P < 0.01, respectively]. Only maternal history of AT predicted history of snoring [4.12 (1.86-9.12); P < 0.01]. When entered in the same multivariate logistic regression analysis model, tonsillar hypertrophy was a stronger predictor of habitual snoring than maternal history of AT [4.00 (1.97-8.14) vs. 2.73 (1.20-6.20)].

CONCLUSIONS

Children with parental history of AT have more frequently tonsillar hypertrophy than those without such history. Tonsillar hypertrophy mediates at least in part the association between maternal history of AT and habitual snoring in childhood.

A study of the role of different forms of chronic rhinitis in the development of otitis media with effusion in children affected by adenoid hypertrophy

OBJECTIVE

The aim of the present study was to evaluate the role of the different forms of chronic rhinitis in the pathogenesis of otitis media with effusion in children affected by obstructive adenoid hypertrophy.

METHODS

81 patients, aged between 4 and 15 years (mean age of 6.9 years), affected by obstructive adenoid hypertrophy were evaluated. All patients underwent accurate history taking, physical examination with endoscopy of the nasopharynx, skin prick test, nasal cytology and hearing evaluation.

RESULTS

Nasal citology showed that 21% of patients had a non-allergic rhinitis (NAR) subtype, 17.4% NAR overlapping with infectious rhinitis (IR), 29.6% IR, 4.9% allergic rhinitis (AR), 2.5% AR overlapping with IR and the remaining 24.6% a negative cytology. The presence of OME was positively correlated with neutrophils (p = 0.01) and mast cells (p = 0.022), while it was negatively correlated with the presence of eosinophils (p = 0.02) and bacteria (p = 0.02).

CONCLUSIONS

A chronic rhinitis was present in more than 70% of children with AH and 60% of them showed OME. Nasal cytology together with SPT showed that AR was rarely present in this group of children, while the mast-cells and neutrophils positively correlated with OME.

Deep cervical lymph node hypertrophy: a new paradigm in the understanding of pediatric obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

To determine if adenotonsillar hypertrophy is an isolated factor in pediatric obstructive sleep apnea (OSA), or if it is part of larger spectrum of cervical lymphoid hypertrophy.

STUDY DESIGN

Prospective case control study.

METHODS

A total of 70 screened patients (mean age 7.47 years) underwent polysomnography to confirm OSA, and then underwent MRI of the upper airway. Seventy-six matched controls (mean age 8.00 years) who already had an MRI underwent polysomnography. Volumetric analysis of lymphoid tissue volumes was carried out. Chi-square analysis and Student's t test were used to compare demographic data and lymph node volumes between cohorts. Fisher's Exact test and Chi-square analysis were used to compare sleep data.

RESULTS

Patients and controls demonstrated no significant difference in mean age (7.47 vs. 8.00 yrs), weight (44.87 vs. 38.71 kg), height (124.68 vs. 127.65 cm), or body-mass index (23.63 vs. 20.87 kg/m(2)). OSA patients demonstrated poorer sleep measures than controls (P < 0.05) in all polysomnography categories (sleep efficiency, apnea index, apnea-hypopnea index, baseline SpO2, SpO2 nadir, baseline ETCO2, peak ETCO2 , and arousal awakening index). Children with OSA had higher lymphoid tissue volumes than controls in the retropharyngeal region (3316 vs. 2403 mm(3), P < 0.001), upper jugular region (22202 vs. 16819 mm(3), P < 0.005), and adenotonsillar region (18994 vs. 12675 mm(3), P < 0.0001).

CONCLUSIONS

Children with OSA have larger volumes of deep cervical lymph nodes and adenotonsillar tissue than controls. This finding suggests a new paradigm in the understanding of pediatric OSA, and has ramifications for future research and clinical care.

Familial risk of sleep-disordered breathing

OBJECTIVE

To estimate the incidence of hospitalization for paediatric obstructive sleep apnoea syndrome (OSAS) or sleep-disordered breathing (SDB) caused by adenotonsillar or tonsillar hypertrophy without infection in children with a parent affected by OSAS.

PATIENTS AND METHODS

Using the MigMed database at Lund University, hospital data on all children aged 0-18 years in Sweden between 1997 and 2007 (total of 3 million individuals) were used to identify all first hospital admissions for OSAS or either adenotonsillar or tonsillar hypertrophy. Next, individuals were categorized as either having or not having a parent affected by OSAS. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were estimated for boys and girls with a parent affected by OSAS. Children with OSAS or adenotonsillar or tonsillar hypertrophy without a parent affected by OSAS acted as the reference group (SIR=1).

RESULTS

After accounting for socio-economic status, age, and geographic region, the SIRs of OSAS in boys and girls with a parent affected by OSAS were 3.09 (95% CI 1.83-4.90) and 4.46 (95% CI 2.68-6.98), respectively. The SIRs of adenotonsillar or tonsillar hypertrophy in boys and girls with a parent affected by OSAS were 1.82 (95% CI 1.54-2.14) and 1.56 (95% CI 1.30-1.87), respectively.

CONCLUSION

This study indicates familial clustering of sleep-disordered breathing, which is important information for clinicians.

Racial/ethnic differences in the prevalence of snoring and sleep disordered breathing in young children

STUDY OBJECTIVE

To determine whether there are racial/ethnic differences in the prevalence of pediatric snoring and sleep disordered breathing (SDB).

METHODS

In this cross-sectional study, parents or caretakers of 346 children, aged 2 through 6 years, attending well-child care visits at 5 general pediatric offices and clinics (3 academic, 2 private) in Brooklyn, NY completed the Sleep-Related Breathing Disorders Scale of the Pediatric Sleep Questionnaire (PSQ) along with a survey on demographics, prior treatment for SDB, and parental knowledge of pediatric SDB. The child's height and weight were recorded from the office visit.

RESULTS

The prevalence of snoring was 13.9% (95% CI 10.2, 17.5) and of SDB was 9.4% (95% CI 6.3, 12.6). The odds of snoring for black children was 2.5 as great as for white children, and for Hispanic children was 2.3 as great as for white children (p = 0.031). There was a higher, non-statistically significant prevalence of abnormal PSQ scores in black and Hispanic children than white children. On multivariate analysis, only black race (OR 3.1 95% CI 1.1, 8.9) and prematurity (OR 4.4 95% CI 1.6, 12.4) were associated with snoring; male gender (OR 2.9 95% CI 1.1, 8.5) was associated with SDB. Knowledge regarding SDB was low among parents and caretakers. The degree of knowledge present was not associated with parental concern about snoring and discussion of the snoring with the child's pediatrician.

CONCLUSIONS

Black race and prematurity are independent predictors of snoring. The degree of parental knowledge regarding SDB was not associated with seeking medical treatment.

Neurocognitive performance and behavior before and after treatment for sleep-disordered breathing in children

Neurocognitive and behavioral problems are increasingly reported in children with sleep-disordered breathing (SDB). The impact of treatment for SDB on neurocognition and behavior is, therefore, an issue of increasing importance. To date, there has been little consideration given to the quality of studies when reviewing associated neurocognitive and behavioral problems in children with SDB, and furthermore, there has been little systematic review of treatment outcomes. The aim of this review was to provide an up-to-date and critical review of the current literature. Findings indicate a specific pattern of neurocognitive problems in children with SDB; however, the pattern of behavioral problems is less clear. Very few studies were found to provide a rigorous investigation of posttreatment neurocognitive and behavior outcomes. Despite this, relatively consistent improvements in global intelligence, attention, and visual spatial ability are shown; however, persistent deficits in other domains are also evident. For behavior, problems of hyperactivity, aggression or conduct problems, and somatic complaints improve following treatment. In contrast, symptoms of anxiety and social problems less consistently improve. These findings should aid in the development of more targeted investigations and well-designed studies exploring both the causative mechanisms and the treatment response for neurocognitive and behavior problems in children with SDB.