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Childhood Obstructive Sleep Apnea

PCCSU Volume 25, Lesson 31

PCCSU

The American College of Chest Physicians offers this lesson as a review of a previously offered self-study program. The program provides information on pulmonary, critical care, and sleep medicine issues. CME is no longer available for the PCCSU program.

Objectives

  • Update your knowledge and understanding of pulmonary medicine topics.
  • Update your knowledge and understanding of critical care medicine topics.
  • Update your knowledge and understanding of sleep medicine topics.
  • Learn clinically useful practice procedures.

CME Availability

Effective July 1, 2013, PCCSU Volume 25 is available for review purposes only.

Effective December 31, 2012, PCCSU Volume 24 is available for review purposes only.

Effective December 31, 2011, PCCU Volume 23 is available for review purposes only. CME credit for this volume is no longer being offered

Effective December 31, 2010, PCCU Volume 22 is available for review purposes only. CME credit for this volume is no longer being offered.

Accreditation Statement

The American College of Chest Physicians is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

CME Statement

Credit no longer available as of July 1, 2013.

Disclosure Statement

The American College of Chest Physicians (CHEST) remains strongly committed to providing the best available evidence-based clinical information to participants of this educational activity and requires an open disclosure of any potential conflict of interest identified by our faculty members. It is not the intent of CHEST to eliminate all situations of potential conflict of interest, but rather to enable those who are working with CHEST to recognize situations that may be subject to question by others. All disclosed conflicts of interest are reviewed by the educational activity course director/chair, the Education Committee, or the Conflict of Interest Review Committee to ensure that such situations are properly evaluated and, if necessary, resolved. The CHEST educational standards pertaining to conflict of interest are intended to maintain the professional autonomy of the clinical experts inherent in promoting a balanced presentation of science. Through our review process, all CHEST CME activities are ensured of independent, objective, scientifically balanced presentations of information. Disclosure of any or no relationships will be made available for all educational activities.

CME Availability

Volume 25 Through June 30, 2013
Volume 24 Through December 31, 2012
Volume 23 Through December 31, 2011
Volume 22 Through December 31, 2010

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PCCSU Volume 25 Editorial Board

Editor-in-Chief
Steven A. Sahn, MD, FCCP

Director, Division of Pulmonary and Critical Care Medicine, Allergy, and Clinical Immunology
Medical University of South Carolina
Charleston, SC

Dr. Sahn has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Deputy Editor
Richard A. Matthay, MD, FCCP

Professor of Medicine
Section of Pulmonary and Critical Care Medicine
Yale University School of Medicine
New Haven, CT

Dr. Matthay has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Alejandro C. Arroliga, MD, FCCP
Professor of Medicine
Texas A&M Health Science Center
College of Medicine
Temple, TX

Dr. Arroliga has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Paul D. Blanc, MD, FCCP
Professor of Medicine
University of California, San Francisco
San Francisco, CA

Dr. Blanc has disclosed significant relationships with the following companies/organizations whose products or services may be discussed within Volume 25:

National Institutes of Health, Flight Attendants Medical Research Institute – university grant monies
University of California San Francisco, US Environmental Protection Agency, California Environmental Protection Agency Air Resources Board – consultant fee
Habonim-Dror Foundation Board of Trustees – fiduciary position

Guillermo A. do Pico, MD, FCCP
Professor of Medicine
University of Wisconsin Medical School
Madison, WI

Dr. do Pico has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Ware G. Kuschner, MD, FCCP
Associate Professor of Medicine
Stanford University School of Medicine
Palo Alto, CA

Dr. Kuschner has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Teofilo Lee-Chiong, MD, FCCP
Associate Professor of Medicine
National Jewish Medical Center 
Denver, CO

Dr. Lee-Chiong has disclosed significant relationships with the following companies/organizations whose products or services may be discussed within Volume 25:

National Institutes of Health – grant monies (from sources other than industry)
Covidien, Respironics, Inc. – grant monies (from industry-related sources)
Elsevier – consultant fee

Margaret Pisani, MD, MPH, FCCP
Assistant Professor of Medicine
Yale University School of Medicine 
New Haven, CT

Dr. Pisani has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Stephen I. Rennard, MD, FCCP
Professor of Medicine
University of Nebraska Medical Center
Omaha, NE

Dr. Rennard has disclosed significant relationships with the following companies/organizations whose products or services may be discussed within Volume 25:

AstraZeneca, Biomark, Centocor, Novartis – grant monies (from industry-related sources)

Almirall, Aradigm, AstraZeneca, Boehringer Ingelheim, Defined Health, Dey Pharma, Eaton Associates, GlaxoSmithKline, Medacrop, Mpex, Novartis, Nycomed, Otsuka, Pfizer, Pulmatrix, Theravance, United Biosource, Uptake Medical, VantagePoint – consultant fee/advisory committee

AstraZeneca, Network for Continuing Medical Education, Novartis, Pfizer, SOMA – speaker bureau

Ex Officio
Gary R. Epler, MD, FCCP

Clinical Associate Professor of Medicine
Harvard Medical School
Brigham & Women's Hospital
Boston, MA

Dr. Epler has disclosed no significant relationships with the companies/organizations whose products or services may be discussed within Volume 25.

Lilly Rodriguez
ACCP Staff Liaison


By Keisha Shaheed, DO; and Ann C. Halbower, MD

Dr. Shaheed is a Sleep Medicine Fellow at National Jewish Health/Children’s Hospital Colorado, Denver, Colorado. Dr. Halbower is an Associate Professor of Pediatrics, Section of Pulmonary Medicine at Children’s Hospital Colorado and the University of Colorado, Denver, Colorado.

Dr. Shaheed and Dr. Halbower have disclosed no significant relationships with the companies/organizations whose products or services may be discussed within this chapter.

Objectives

  1. Discuss the pathophysiology and epidemiology of sleep-disordered breathing in the pediatric population.
  2. Outline diagnostic and treatment modalities for assessing and managing obstructive sleep-disordered breathing in the pediatric population.
  3. Alert the primary care provider to signs and symptoms that would suggest sleep-disordered breathing in children.

Key Words: childhood OSAS; pediatric obstructive sleep apnea; sleep-disordered breathing

Abbreviations: AAP = American Academy of Pediatrics; AASM = American Academy of Sleep Medicine; ICSD-2 = International Classification of Sleep Disorders; OSA = obstructive sleep apnea; OSAS = obstructive sleep apnea syndrome; PSG = polysomnogram; REM = rapid eye movement; SDB = sleep-disordered breathing.

Gap in Professional Practice

As the general medical community has come to appreciate the importance of early identification and appropriate management of obstructive sleep apnea (OSA) in children, a need for evidence-based guidance has emerged. Obstructive sleep apnea syndrome (OSAS) is a common disorder in the pediatric population with an estimated prevalence of 1% to 5%.1

The spectrum of obstructive sleep-disordered breathing (SDB) runs the gamut from primary snoring to upper airway resistance syndrome to varying degrees of OSA. SDB has been found to have not only physical but neurocognitive consequences and thus warrants identification and treatment.2 Debate is ongoing about how to best evaluate and treat patients who fall into the spectrum of SDB without carrying an official diagnosis of OSAS.3

General pediatricians, parents, and educators need to be aware of clinical signs as well as the biophysical and neurocognitive consequences of untreated obstructive SDB in children. The task falls to the specialists who treat these patients to develop uniform and comprehensive guidelines for diagnosis, management, and follow-up for these conditions.

Introduction

The International Classification of Sleep Disorders (ICSD-2) has defined apnea in the pediatric patient as a cessation of airflow over two or more attempted respiratory cycles.1 A hypopnea is defined as a reduction (either qualitative or quantitative depending on the laboratory) in airflow over two or more respiratory cycles, accompanied by a 3% (or 4%) fall in oxygen saturation and/or terminated by an arousal. Obstructive sleep apnea syndrome is a disorder of breathing during sleep characterized by prolonged partial or intermittent complete upper airway obstruction (hypopnea or obstructive apnea, respectively) that impairs normal ventilation and sleep pattern.4

It has been reported that 7% to 12% of children, depending on age ranges studied, snore during sleep and about one-third of these children will have some degree of OSA diagnosed by overnight polysomnogram (PSG).

There are many possible causes for the development of obstructive SDB in children. Commonly there is a contribution from mechanical obstruction working in tandem with neuromotor tone deficits. Therefore, the disorder is seen in association with adenotonsillar hypertrophy, muscular dystrophy, and complex genetic conditions like Down syndrome, Prader-Willi syndrome, and Marfan syndrome. Obstructive SDB can also be seen in those with obesity, midfacial dysplasia, retrognathia, micrognathia, or allergic rhinitis.

Consequences of untreated OSA in children include failure to thrive; neuropsychological and behavioral problems, such as inattention, aggression, restlessness, and depression; and cardiovascular problems, such as systemic and pulmonary hypertension and increased inflammatory markers of cardiovascular risk. OSA is also felt to play a large role in the increase of insulin resistance in obese children.5 Significant improvements in lipid profiles and C-reactive protein have been seen after treatment of OSA in both nonobese and obese children.6

The PSG is currently the gold standard for diagnosis of OSA. A recent set of practice parameters from the American Academy of Sleep Medicine (AASM) recommended PSG for children with clinically suspected OSAS7 (endorsed by the American Academy of Pediatrics).1 Obtaining a PSG is limited by its lack of universal availability and long waiting lists in most centers. Overnight PSG has been performed preoperatively in fewer than 10% of children undergoing adenotonsillectomy for obstructive symptoms in the United States.8

In an effort to maximize effective use of limited resources while properly evaluating and treating children, recommendations by American Academy of Pediatrics (AAP) support obtaining either a PSG or an evaluation by a sleep specialist or otolaryngologist if OSAS is suspected.1

The current first line of treatment for pediatric OSAS is adenotonsillectomy. Other treatment modalities are generally reserved for those without anatomical sites of obstruction or with postsurgical residual SDB. These include positive airway pressure, rapid maxillary expanders, and aggressive weight loss. Medical treatment with nasal corticosteroids and a leukotriene antagonist has been shown to be beneficial in treating residual mild SDB, including snoring.9-12

Pathophysiology

The essential feature of OSA in children is increased upper airway resistance during sleep. Airway narrowing may be due to craniofacial abnormalities and soft tissue hypertrophy.

The pathophysiology of OSA in children involves a complex interplay of neuromuscular tone and a vulnerable airway predisposed toward collapse. This results in partial reduction or complete cessation in airflow on a recurrent basis that is often accompanied by increased respiratory effort with gas-exchange abnormalities (oxygen desaturation, hypercapnia) and arousals (sleep fragmentation). Airway collapsibility is influenced by anatomic factors, such as increased soft tissue size, narrow dimensions of the airway, and craniofacial structural abnormalities. However, these alone don’t explain the entire pattern of SDB. Other important variables include the level of neuromuscular activation, ventilatory control, and the arousal threshold. These factors significantly impact the patency of the airway during sleep.

As sleep is initiated, muscle tone in the airway is reduced, which leads to increased CO2 retention (hypercapnia). Pharyngeal dilator muscle activation opposes this narrowing in response to hypercapnia and negative pressure in the airway lumen. Increased respiratory effort, an additional response to hypercapnia, may lead to ventilatory overshoot driving the CO2 level down rapidly. During non-rapid eye movement (REM) sleep, the level of carbon dioxide below which apnea is induced (apneic threshold) is very near the baseline wake (eupneic) levels. The increased respiratory response and the resultant hypocarbia may lead to a sudden reduction in airway muscle activation, contributing to obstruction during non-REM sleep. Cortical and autonomic arousals, a common response to the flow reductions, lead to increased ventilation and may encourage a cycle of obstructive events. Once deeper slow-wave sleep is attained, more stable breathing is observed even in children with severe OSA. This is evidence of successful neuromuscular compensation.7

During REM sleep, atonia of most skeletal muscles appears. This leads to reduction in pharyngeal dilator activity related to central processes. This instability may contribute to the disproportionate severity of OSA observed during REM sleep.

Among obese children, the adipose distribution is thought to play a role in an increased risk of SDB with visceral adipose deposits being associated with increased OSA risk.13

Epidemiology and Clinical Manifestations

The prevalence of pediatric OSAS is approximately 1% to 5% in children.1 Adenotonsillar hypertrophy is the most common anatomical association found with OSAS in children. OSAS is thought to be most common in preschool-aged children, which coincides with the age when the tonsils and adenoids are the largest in relation to the underlying airway size.14

Obesity, hypotonic neuromuscular diseases, and craniofacial anomalies are major risk factors. While obesity is a significant risk factor for SDB, it is important to note that there also is an existing association between being underweight and SDB.15

Snoring is the most common complaint in children with OSAS, but clinical presentation varies according to age. Children with habitual snoring may have recognizable breathing abnormalities during sleep, including inspiratory flow limitation, increased respiratory effort, and tachypnea.3,16

Agitated sleep with frequent postural changes, excessive sweating, or abnormal sleep positions, such as hyperextension of the neck may suggest SDB.

Night terrors, sleepwalking, and enuresis are frequently associated with SDB. Excessive daytime sleepiness becomes apparent in older children, whereas hyperactivity or inattention is usually predominant in younger children. Morning headache and poor appetite also may be present.

As the cortical arousal threshold is higher in children, their sleep architecture is usually more conserved than that of adults.17

Untreated OSAS in children may result in problems, such as cognitive deficits, attention deficit/hyperactivity symptoms, poor academic achievement, and emotional instability. Clinical features of OSAS are listed in Table 1.


Table 1Clinical Features of OSAS

Nighttime Daytime
Snoring/noisy breathing; worse during URI or allergic rhinitis Grogginess in morning
Mouth breathing Headache, dry mouth, or sore throat on awakening
Neck hypertension during sleep Behavioral changes (hyperactive behavior [young children < 8 years])
Restless sleep Learning, attention, and executive function deficits
Excessive perspiration Daytime sleepiness
Witnessed apneas (less frequent than in adults) Mouth breathing during wakefulness
Nocturnal enuresis  
Sleepwalking, sleep-talking, and night terrors  

Conditions associated with SDB include the following:

  • Adenotonsillar hypertrophy with or without allergic rhinitis
  • Obesity
  • Craniofacial anomalies
    • Choanal atresia
    • Small mandible with or without mandibular malpositioning
    • Narrow nasomaxillary complex with or without high and narrow, hard palate
    • Cleft palate repair causing scarring
    • Marked nasomaxillary (midface) deficiency (eg, Apert syndrome, Crouzon syndrome, Pfeiffer syndrome)
    • Marked mandibular hypoplasia (eg, Pierre Robin sequence, severe juvenile rheumatoid arthritis, Treacher Collins syndrome, Nager syndrome, Stickler syndrome)
  • Abnormal neuromotor tone and/or control of breathing
    • Duchenne muscular dystrophy
    • Spinal muscle atrophy
  • Brainstem disorders
    • Chiari malformation
    • Syringobulbia
  • Sickle cell disease
  • Combinations of the above disorders or conditions
    • Down syndrome
    • Achondroplasia
    • Prader-Willi syndrome
    • Mucopolysaccharidoses

Diagnosis

Overnight polysomnography is considered the gold standard for diagnosis of the presence and severity of OSAS. Performance of PSG using standardized methods has strong clinical utility in the diagnosis and management of SDB in children. PSG technology used in the majority of sleep laboratories may, however, be inadequate to diagnose subtle forms of clinically important airflow limitation associated with daytime dysfunction. New diagnostic technologies are on the horizon, however.14 In the meantime, the combined use of multiple diagnostic sensors, such as nasal pressure sensors, end-tidal CO2 measurements, and the esophageal pressure manometer have improved diagnostic sensitivity. Most importantly, the PSG should be read by a professional with expertise in interpreting the subtle changes that may be clinically significant, if not overt.3 Accurate diagnosis and management of SDB in children is best accomplished through careful integration of PSG findings with the clinical evaluation.

Treatment

Adenotonsillectomy is considered the first line of treatment for OSA in children. Adenotonsillectomy has been associated with improvement in symptoms and neurocognitive outcomes even in cases where no confirmed OSAS was present on PSG. Cure rates approach 90% in typically developing nonobese children under 7 years of age with adenotonsillar hypertrophy. However, residual sleep disorder breathing occurs in 20% to 40% of patients from a variety of clinical settings and up to 75% of those with obesity.13,18

High-risk patients, such as those with chronic lung disease, neuromuscular disorders, craniofacial anomalies, sickle cell disease, hypoventilation syndromes, or obesity should be hospitalized overnight after surgery and monitored continuously. To assess the need for further treatment, follow-up PSG is recommended after adenotonsillectomy in patients with severe preoperative OSA, obese patients, and any patient who has persistent postsurgical symptoms.15

Other adjunctive surgical inventions might be useful to alleviate other anatomical sites of obstructions. Turbinate reduction, septoplasty, and lingual tonsillectomy are a few such procedures.

Positive airway pressure is the first-line treatment option for severe OSA, with or without hypoventilation, which is not amenable to surgical intervention or is residual after surgery. Continuous and bilevel positive pressures have both been found to be effective in treatment of OSA. With adequate treatment, reversal of the nighttime symptoms and resolution of many of the daytime symptoms and neurocognitive deficits are present.6 Poor tolerance and compliance continue to be issues with these modalities. Further limitations of the use of positive pressure include few pediatric-sized mask being available, and long-term use of nasal mask interfaces may lead to deformation or compression of the maxillary bones. A switch to nasal prong interfaces may help with this problem in developing children.

Newer modalities like rapid maxillary expanders (RME) and mandibular advancement oral appliances (approved for age 16 and up) have shown some efficacy in treatment of OSA in those with amenable anatomy (eg, high arched palate, dental malocclusion, or small jaw). Longitudinal studies will be beneficial in determining whether the RME, by altering their anatomy, can reduce their OSA risk as adults.

There is no consensus as to which combination of symptoms, physical examination, and PSG findings warrant surgical intervention in mild SDB in children. Some evidence supports the use of nasal corticosteroids and leukotriene antagonist in the treatment of snoring and mild SDB. The combination of the two medications has been effective in treating residual mild SDB after adenotonsillectomy.9-12 This illustrates the importance of the clinical judgment of the medical provider in evaluating all factors and available evidence and making treatment and follow-up decisions accordingly.

An algorithm for the approach to pediatric SDB has been recently proposed by two centers. It highlights the need for not only parental observation but also objective evaluation and a competent medical professional to evaluate all of the relevant information and to make management decisions.17

Figure 1 outlines the approach of our center.


Lesson 31 Figure 1

Figure 1. History: snoring, restless sleep, unusual sleep positions, mouth breathing, paradoxical breathing, nocturnal enuresis, daytime hyperactivity, or sleepiness. Physical: tonsillar hypertrophy, crowded oropharynx, craniofacial abnormalities, dental malocclusion, nasal obstruction, adenoid face, obesity, Down syndrome, and Prader-Willi syndrome.
Note: Children sent for adenotonsillectomy without prior PSG may require a postoperative PSG to determine a cure, especially those in high-risk groups or with persistent symptoms. Differential diagnosis for persistent sleepiness includes narcolepsy, delayed sleep phase syndrome, and drug use. Gas exchange abnormalities stem from multiple diagnoses, including central hypoventilation and may require follow-up with a pulmonologist.


Conclusion

SDB in pediatric population has become recognized as an important cause of morbidity that warrants identification and consistent treatment and management. With the rising incidence of obesity among pediatric patients, it is important to recognize this as a significant risk factor for OSAS and to screen these patients appropriately.

Standardization of diagnostic criteria of and widely available diagnostic modalities of SDB are imperative. Individualization of treatment and follow-up plans will allow for better long-term management of children with varying degrees of need.

Upcoming protocols for evaluation, treatment, and follow-up will be helpful in alerting the general pediatrician as to signs and symptoms that are most clinically salient. Additionally, these protocols will provide guidance to help determine when to refer to a specialist.

More studies are needed to determine the best diagnostic modalities to evaluate the full spectrum of SDB symptoms. Well-tolerated and efficacious treatment modalities that can accommodate the changing anatomy of the pediatric patient are needed.

The pediatric dentist will likely have more of a role in the future both in identifying children at risk for SDB and treating these patients when they have anatomy amenable to dental intervention.


References

  1. Marcus CL, Brooks LJ, Draper KA, et al. Diagnosis and management of childhood obstructive sleep apnea syndrome. Pediatrics. 2012;130(3):576-584.
  2. Katz ES, D'Ambrosio CM. Pathophysiology of pediatric obstructive sleep apnea. Proc Am Thorac Soc. 2008;5(2):253-262.
  3. Brockmann PE, Urschitz MS, Schlaud M, Poets CF. Primary snoring in school children: prevalence and neurocognitive impairments. Sleep Breath. 2012;16(1):23-29.
  4. Rosen CL, D'Andrea L, Haddad GG. Adult criteria for obstructive sleep apnea do not identify children with serious obstruction. Am Rev Respir Dis. 1992;146(5 Pt 1):1231-1234.
  5. American Academy of Pediatrics; Section on Pediatric Pulmonology, Subcommittee on Obstructive Sleep Apnea Syndrome. Clinical practice guideline: diagnosis and management of childhood obstructive sleep apnea syndrome. Pediatrics. 2002;109(4):704-712.
  6. Chervin RD, Burns JW, Subotic NS, Roussi C, Thelen B, Ruzicka DL. Correlates of respiratory cycle-related EEG changes in children with sleep-disordered breathing. Sleep. 2004;27(1):116-121.
  7. Guilleminault C, Li K, Khramtsov A, Palombini L, Pelayo R. Breathing patterns in prepubertal children with sleep-related breathing disorders. Arch Pediatr Adolesc Med. 2004;158(2):153-161.
  8. Alexopoulos EI, Kaditis AG, Kalampouka E, Kostadima E, Angelopoulos NV, Mikraki V, et al. Nasal corticosteroids for children with snoring. Pediatr Pulmonol. 2004;38(2):161-167.
  9. Goodwin JL, Kaemingk KL, Mulvaney SA, Morgan WJ, Quan SF. Clinical screening of school children for polysomnography to detect sleep-disordered breathing: the Tucson Children's Assessment of Sleep Apnea study (TuCASA). J Clin Sleep Med. 2005;1(3):247-254.
  10. Kheirandish L, Goldbart AD, Gozal D. Intranasal steroids and oral leukotriene modifier therapy in residual sleep-disordered breathing after tonsillectomy and adenoidectomy in children. Pediatrics.2006;117(1):e61-e66.
  11. Goldbart AD, Greenberg-Dotan S, Tal A. Montelukast for children with obstructive sleep apnea: a double-blind, placebo-controlled study. Pediatrics. 2012;130(3):e575-e580.
  12. Mitchell RB, Pereira KD, Friedman NR. Sleep-disordered breathing in children: survey of current practice. Laryngoscope. 2006;116(6):956-958.
  13. Halbower AC, Ishman SL, McGinley BM. Childhood obstructive sleep-disordered breathing: A clinical update and discussion of technological innovations and challenges. Chest. 2007;132(6):2030-2041.
  14. Bixler EO, Vgontzas AN, Lin HM, Liao D, Calhoun S, Vela-Bueno A, et al. Sleep disordered breathing in children in a general population sample: prevalence and risk factors. Sleep. 2009;32(6):731-736.
  15. Gozal D. Sleep, sleep disorders and inflammation in children. Sleep Med. 2009;(10 suppl 1):S12-S16.
  16. Kaditis A, Kheirandish-Gozal L, Gozal D. Algorithm for the diagnosis and treatment of pediatric OSA: a proposal of two pediatric sleep centers. Sleep Med. 2012;13(3):217-227.
  17. Kang KT, Lee PL, Weng WC, Hsu WC. Body weight status and obstructive sleep apnea in children [published online ahead of print]. Int J Obes (Lond). 2012. doi: 10.1038/ijo.2012.5.
  18. Kheirandish-Gozal L, Gozal D. Intranasal budesonide treatment for children with mild obstructive sleep apnea syndrome. Pediatrics. 2008;122(1):e149-e155.