Cardiovascular Risk in Pediatric Obstructive Sleep Apnea: What Do We Know?

These changes, along with hypoxemia and hypercapnia, which act on peripheral and central chemoreceptors, cause further changes in blood pressure. It is also possible that this repetitive stress attenuates the sensitivity of the baroreflex response, further promoting hypertension in OSA. Hypoxia and increased sympathetic tone affect renin-angiotensin system activation, further promoting an increase in blood pressure.

There is also evidence that proinflammatory markers are increased in children with OSA, and these can be reduced by CPAP treatment. In addition, hypoxemia and reperfusion during apneas is linked to increased free reactive radicals. Taken together, these effects can lead to increased CV effects of OSA.

As a result of these autonomic, inflammatory, and renin-angiotensin changes, children with OSA are at a higher risk of developing elevated blood pressure during sleep and wakefulness. However, it is important to note that children appear to be more resilient than adults to the development of hypertension, as several cross-sectional studies of children with OSA did not demonstrate blood pressure increases compatible with current definitions of hypertension.

On the other hand, there is growing evidence that children with underlying medical conditions are more severely affected by OSA. Screening for OSA and polysomnography are recommended in multiple disorders, such as trisomy 21, myotonic dystrophy, Prader-Willi syndrome, and DiGeorge syndrome, as these patients are more likely to be diagnosed with OSA and have more severe adverse effects.⁶

Dr Chawla: Generally, pediatricians recognize that in pediatric patients who already have hypertension, a small number may have OSA. But the general CV risks that are well known in adult patients with OSA are not well-delineated in pediatric patients. Specifically, at this time we do not have a body of knowledge that helps us understand endothelial injury, inflammatory responses, or anything beyond correlation with metabolic risks.

Pulmonology Advisor: What steps should a general pediatrician take when they encounter a child who they suspect may have OSA?

Dr Stille: The first thing is to take a thorough history, especially related to upper airway (ENT, allergy, trauma, family history and/or any genetic factors predisposing to obstruction) and lower airway (asthma, other chronic lung disease) issues. Focus on where the obstruction might be, and what about it might be easily addressed in primary care — many kids with allergies or sinus problems can be initially treated without referral.

The second step is to get a good idea of how symptoms are affecting the child — for example, sleep quality, daytime sleepiness or irritability, school functioning, and headaches. Kids who snore without obvious breathing pauses may or may not have problems because of it. Third, many children have had some symptoms for a long period of time, so inquiring about what’s already been done (eg, allergy treatment) is important. Finally, if a decision is made to refer to a specialist such as an ENT or a pulmonologist, the specific goals of the referral should be discussed with the family and communicated to the specialist.

Dr Mohon: No perfect screening tools currently exist for identifying a pediatric patient who may have a sleep-related breathing disorder such as OSA. Certainly, whether or not a child has nighttime snoring is always a good question to ask at routine pediatric visits. Additional questions including whether there is gasping or choking during sleep; restless sleep; daytime irritability; behavioral issues including anxiety, hyperactivity, and poor concentration in school, which all suggest a possible sleep problem that would justify a referral to a pediatric sleep specialist.

Dr Khaytin: The American Academy of Pediatrics recommends that every child and adolescent be asked about the presence of snoring.⁶ Additional history of gasping, dry mouth, night sweating, daytime sleepiness, school problems, attention problems, and/or behavioral problems can point to the presence of OSA. Failure to thrive in infancy may also be a manifestation of OSA.⁶ One of the most common ways to uncover excessive daytime sleepiness is the modified Epworth sleepiness scale, with a score <10 being normal.⁷ Most pediatric sleep centers accept outside referrals for polysomnographic studies so that at-risk infants and children can be proactively identified.

Dr Chawla: A pediatrician should first understand whether their patient is a chronic needs/special needs care patient or a generally healthy patient. For a chronic needs/special needs care patient, if a clinician suspects OSA they should send the patient to a sleep specialist or for a sleep study to further delineate what the underlying issues may be.

In patients with chronic needs, regardless of whether or not they have symptoms of OSA, pediatricians should be thinking about OSA. For example, patients with trisomy 21 and patients with cerebral palsy have a high prevalence of sleep apnea.⁶ So, pediatricians should be thinking of OSA in complex care patients regardless of whether or not they are presenting symptoms.

In patients who are generally healthy, if a pediatrician suspects OSA, they should send those patients to an ENT surgeon for evaluation of an adenotonsillectomy. Well-child checks are a perfect opportunity to ask whether children are snoring. But pediatricians should be thinking about OSA at every opportunity if children have learning disabilities or behavioral challenges, and specifically if a patient presents with attention concerns or physical findings of obesity or insulin resistance.

Pulmonology Advisor: How do pediatricians collaborate with pulmonologists, sleep medicine folks, or other relevant specialists regarding these patients?

Dr Stille: The most important thing initially is for the primary care practice to communicate the reason for the referral, along with specific questions the family or pediatrician might have. Information from your own work-up will save time and resources. A history of what has been tried previously is also important. After the referral, communication about what the specialist is thinking and why, initial plans, and what parents and the pediatrician might watch for or accomplish as part of the longer-term plan completes the circle.

In many locations, specialty access to ENT or pulmonary care is difficult. While sleep studies and surgery need to be done by specialists, pediatricians can learn some basic work-ups and treatment in collaboration with specialty colleagues that can help many kids get relief they need more quickly.

Dr Khaytin: Children with OSA can benefit from a multidisciplinary approach. Children with symptoms of OSA should have a polysomnographic study performed, preferably at a pediatric sleep center, since a child-friendly environment and sleep technologists with experience in pediatric polysomnography may make the experience more pleasant for the child and family and provide better quality and more representative data. Although the site of the airway obstruction may vary, it is most commonly at the level of the tonsils and adenoids. So, the initial management of OSA in children is usually adenotonsillectomy, after consultation with a pediatric ENT. If the OSA pre-operatively is in the moderate to severe range, the sleep study needs to be repeated 6 to 8 weeks after surgery to confirm resolution.

Children who have other comorbidities, such as significant allergies, asthma, lung disease, or a musculoskeletal or neuromuscular disorder, should be seen at a multidisciplinary sleep medicine clinic that includes a pediatric pulmonologist and/or a neurologist. About 20% to 40% of children who have adenotonsillectomy continue to have some degree of OSA after surgery, which requires initiation of CPAP therapy with mask ventilation in the home.⁸ Experienced sleep technologists and sleep psychologists can significantly improve adherence to PAP treatment. Since studies have demonstrated that a higher BMI is often associated with OSA, a pediatric weight management program is also of great benefit to children with OSA.¹

Dr Chawla: As pediatricians recognize patients with learning concerns, behavioral concerns, or physical findings of obesity or insulin resistance, they should consider ENT referrals or referrals to sleep medicine or pulmonary medicine. At this time, it is really important for pediatricians to know their resources for management of patients who are obese or at CV risk and to potentially partner with cardiologists in the care of these patients.

Pulmonology Advisor: What should be next steps in this area in terms of research, physician education, or otherwise?

Dr Mohon: Research in adult patients does not directly reflect the potential risk in the pediatric population. More focus is needed on this vulnerable population, including following them in a longitudinal fashion for early signs of disease that may be a consequence of sleep-related breathing disorders.

Dr Khaytin: Significant research and development are still needed to better understand the mechanisms and management of OSA. Growing evidence shows that OSA can affect children as young as infancy; however, the mechanism of pathogenesis and even normative values in infants are still being investigated. Successful management of OSA in infants and young children is dramatically limited by the number of masks that fit their developing faces. Most current masks for CPAP are scaled-down adult equivalents, which can lead to poor fit and mid-face hypoplasia.

Alternatives to CPAP such as nasal corticosteroids are being actively investigated, especially in children with mild OSA.¹ In addition, even though many CV and neurobehavioral consequences are known to be associated with OSA, the exact mechanism and long-term outcomes are still being studied. Physician and parental awareness about OSA are increasing early diagnosis and leading to early initiation of treatment. Screening for OSA is now part of the management of multiple pediatric chronic medical conditions.

Dr Chawla: When it comes to the educational component, right now the typical pathway for identifying CV risk in patients with OSA starts when clinicians recognize patients with hypertension, refer them to obesity programs for management and/or cardiologists for treatment, but fail to recognize early the opportunity to also manage OSA as an etiology for the hypertension.

For the research component, it would be helpful to hear and learn more from the adult communities on pediatric CV risks associated with OSA, specifically lifetime endothelial, immunologic, and metabolic risks for their patients.

References

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4. Koren D, Gozal D, Philby MF, Bhattacharjee R, Kheirandish-Gozal L. Impact of obstructive sleep apnoea on insulin resistance in nonobese and obese children. Eur Respir J. 2016;47(4):1152-1161.
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