Understanding the Anatomic Basis for Obstructive Sleep Apnea Syndrome in Adolescents

Abstract

Rationale: Structural risk factors for obstructive sleep apnea syndrome (OSAS) in adolescents have not been well characterized. Because many adolescents with OSAS are obese, we hypothesized that the anatomic OSAS risk factors would be more similar to those in adults than those in children.Objectives: To investigate the anatomic risk factors in adolescents with OSAS compared with obese and lean control subjects using magnetic resonance imaging (MRI).Methods: Three groups of adolescents (age range: 12-16 yr) underwent MRI: obese individuals with OSAS (n = 49), obese control subjects (n = 38), and lean control subjects (n = 50). Measurements and Main Results:We studied 137 subjects and found that (1) obese adolescents with OSAS had increased adenotonsillar tissue compared with obese and lean control subjects; (2) obese OSAS adolescents had a smaller nasopharyngeal airway than control subjects; (3) the size of other upper airway soft tissue structures (volume of the tongue, parapharyngeal fat pads, lateral walls, and soft palate) was similar between subjects with OSAS and obese control subjects; (4) although there were no major craniofacial abnormalities in most of the adolescents with OSAS, the ratio of soft tissue to craniofacial space surrounding the airway was increased; and (5) there were sex differences in the pattern of lymphoid proliferation.Conclusions: Increased size of the pharyngeal lymphoid tissue, rather than enlargement of the upper airway soft tissue structures, is the primary anatomic risk factor for OSAS in obese adolescents. These results are important for clinical decision making and suggest that adenotonsillectomy should be considered as the initial treatment for OSAS in obese adolescents, a group that has poor continuous positive airway pressure adherence and difficulty in achieving weight loss.Keywords: adenoid; adolescents; MRI; obstructive sleep apnea syndrome; tonsils The obstructive sleep apnea syndrome (OSAS) is common in children and adults, but it has not been well studied in adolescents. In one study, researchers reported the prevalence of OSAS in adolescents to be 2% (1), but the prevalence is probably higher in the United States because of the adolescent obesity epidemic (2). OSAS in children is thought to be secondary to a combination of enlargement of the lymphoid tissue (tonsils and adenoid) (3) and, sometimes, obesity, as well as to reductions in neuromuscular tone (4). In adults, there are known anatomic risk factors for OSAS, including enlargement of the tongue, soft palate, parapharyngeal fat pads, and lateral pharyngeal walls (5) in conjunction with craniofacial restriction (retrognathia) (6). In addition to anatomic factors, physiologic mechanisms increase OSAS risk in both children and adults (7-12). Although these risk factors for OSAS have been well described in children and adults, few Supported by grants from the National Institutes of Health (R01 HL058585, R01 HL089447, and P01 HL094307).Author Contributions: Conception and design: R.J.S., R.M.B., S.H., and C.L...

The obstructive sleep apnoea syndrome in adolescents

“…However, we previously showed both anatomic and physiological differences in adolescents with OSAS compared with controls. Adolescents with OSAS had adenotonsillar hypertrophy and a smaller nasopharyngeal airway than controls,7 a more collapsible airway during both the activated state and the hypotonic state8 and blunted upper airway neuromotor reflex responses to subatmospheric pressure8 and hypercapnia9 during sleep. While these studies established important relationships with individual factors, the relative contribution and interaction of each of these physiological factors to OSAS risk is unknown; very few studies have evaluated both structural and functional components in the same individual.…”

Impact of Adenotonsillectomy on Insulin Resistance and Lipoprotein Profile in Nonobese and Obese Children

“…Also, the wide age distribution of our cohort could have affected interpretation of IR, hyperglycemia, and dyslipidemia, given the mixture of prepubertal and pubertal children. We also did not examine the participants' diet and physical activity pre-and post-T&A, and thus cannot exclude the possibility that some participants significantly changed their food intake patterns and overall activity lifestyle following T&A. Lymphadenoidal hypertrophy also has been found to decline in adolescence, 51 although adolescents with OSA vs without OSA are more likely to have adenotonsillar hypertrophy 52 ; this variability may have affected how the underlying primary contributors to upper airway dysfunction impinge upon metabolic function. Furthermore, glycosylated hemoglobin was not examined, so the impact of OSA treatment on longstanding glycemia could not be assessed.…”

MRI Evaluation of the Oropharyngeal Region in Patients with Obstructive Sleep Apnea Syndrome

“…Bunlardan birincisi faringeal yağ dokusu diğeri ise parafaringeal duvardır (3,4) . Obezitenin apne ki rolü düşünülerek başta faringeal yağ dokusu ölçümleri yapılmış ve üst solunum yolları kaynaklı uyku apneli olgularda bu parametri ölçümlerinde artışın nedenlerden biri olduğunu savunulmuştur (4)(5)(6) . Diğer taraftan BT ile yapılan başka araştırmalarda parafaringeal yağ dokusu ile havayolu arasında bir ilişki olmadığını bildirilmiştir (7,8) .…”