***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND AND OBJECTIVES : Data from a r and omized , controlled study of  adenotonsillectomy for obstructive sleep apnea syndrome ( OSAS ) were used to test the hypothesis that children undergoing surgery had greater quality of life ( QoL ) and symptom improvement than control subjects . The objectives were to compare changes in vali date d QoL and symptom measurements among children r and omized to undergo adenotonsillectomy or watchful waiting ;  to determine whether race , weight , or baseline OSAS severity influenced changes in QoL and symptoms ; and to evaluate associations between changes in QoL or symptoms and OSAS severity . METHODS : Children aged 5 to 9.9 years with OSAS ( N = 453 ) were r and omly assigned to undergo adenotonsillectomy or watchful waiting with supportive care . Polysomnography ,  the Pediatric Quality of Life inventory , the Sleep-Related Breathing Scale of the Pediatric Sleep Question naire , the 18-item Obstructive Sleep Apnea QoL instrument , and the modified Epworth Sleepiness Scale were completed at baseline and 7 months . Changes in the QoL and symptom surveys were compared between arms . Effect modification according to race and obesity and associations between changes in polysomnographic measures and QoL or symptoms were examined . RESULTS : Greater improvements in most QoL and symptom severity measurements were observed in children r and omized to undergo adenotonsillectomy , including the parent-completed Pediatric Quality of Life inventory ( effect size [ ES ] : 0.37 ) , the 18-item Obstructive Sleep Apnea QoL instrument ( ES : –0.93 ) , the modified Epworth Sleepiness Scale score ( ES : –0.42 ) , and the Sleep-Related Breathing Scale of the Pediatric Sleep Question naire ( ES : –1.35 ) . Effect modification was not observed by obesity or baseline severity but was noted for race in some symptom measures . Improvements in OSAS severity explained only a small portion of the observed changes . CONCLUSIONS : Adenotonsillectomy compared with watchful waiting result ed in significantly more improvements in parent-rated generic and OSAS-specific QoL measures and OSAS symptoms BACKGROUND The relative importance of obesity and adenotonsillar hypertrophy in the pathogenesis of obstructive sleep-disordered breathing ( SDB ) in childhood is unclear . Adenotonsillectomy ( AT ) for SDB is not always curative , and obese children are at increased risk for residual disease postoperatively . OBJECTIVE The aim of this investigation was to assess the efficacy of AT as treatment for SDB in obese and nonobese children . METHODS Children with adenoidal and /or tonsillar hypertrophy who underwent AT for the treatment of SDB underwent polysomnography preoperatively and postoperatively .  A body mass index ( BMI ) z score of > 1.645 was used to define obesity . The achievement of a postoperative obstructive apnea-hypopnea index ( OAHI ) of less than one episode per hour ( ie , the cure of SDB ) was the primary outcome measure . RESULTS Twenty-two obese children ( mean [ + /- SD ] age , 5.8 + /- 1.8 years ; mean BMI z score , 2.6 + /- 0.8 ; mean OAHI , 9.5 + /- 9.7 episodes per hour ) and 48 nonobese children ( mean age , 6.9 + /- 2.6 years ; mean BMI z score , 0.09 + /- 1.1 ; OAHI , 6 + /- 5.4 episodes per hour ) were recruited . After surgery , obese and nonobese subjects did not differ in the efficacy of AT  ( postoperative OAHI of less than one episode per hour , 22.7 % vs 25 % of subjects , respectively ; p > 0.05 ) . The presence of obesity , adenoidal or tonsillar hypertrophy , gender , and postoperative BMI change were not significant predictors of SDB cure . CONCLUSIONS Obesity does not necessarily predict an unfavorable outcome of AT as treatment for SDB OBJECTIVE To evaluate the efficacy of adenotonsillectomy ( AT ) in the treatment of children with obstructive sleep apnea ( OSA ) in a 3-y prospect i ve , longitudinal study with analysis of risk factors of recurrence of OSA . STUDY DESIGN An investigation of children ( 6 to 12 y old ) with OSA documented at entry and followed posttreatment at 6 , 12 , 24 , and 36 mo with examination , question naires , and polysomnography . Multivariate generalized linear modeling and hierarchical linear models analysis were used to determine contributors to suboptimal long-term resolution of OSA , and Generalized Linear Models were used for analysis of risk factors of recurrence . RESULTS Of the 135 children , 88 terminated the study at 36 months post-AT . These 88 children ( boys = 72 , mean age = 8.9 ± 2.7 yersus boys 8.9 ± 2.04 y , girls : 8.8 ± 2.07 y ; body mass index [ BMI ] = 19.5 ± 4.6 kg/m(2 ) ) had a preoperative mean apnea-hypopnea index ( AHI0 ) of 13.54 ± 7.23 and a mean postoperative AHI at 6 mo ( AHI6 ) of 3.47 ± 8.41 events/h ( with AHI6 > 1 = 53.4 % of 88 children ) . A progressive increase in AHI was noted with a mean AHI36 = 6.48 ± 5.57 events/h and AHI36 > 1 = 68 % of the studied group . Change in AHI was associated with changes in the OSA-18 question naire . The residual pediatric OSA after AT was significantly associated with BMI , AHI , enuresis , and allergic rhinitis before surgery . From 6 to 36 mo after AT , recurrence of pediatric OSA was significantly associated with enuresis , age ( for the 24- to 36-mo period ) , postsurgery AHI6 ( severity ) , and the rate of change in BMI and body weight . CONCLUSIONS Adenotonsillectomy leads to significant improvement in apnea-hypopnea index , though generally with incomplete resolution , but a worsening over time was observed in 68 % of our cases BACKGROUND AND OBJECTIVES : Adenotonsillectomy for obstructive sleep apnea syndrome ( OSAS ) may lead to weight gain , which can have deleterious health effects when leading to obesity . However , previous data have been from nonr and omized uncontrolled studies , limiting inferences . This study examined the anthropometric changes over a 7-month interval in a r and omized controlled trial of  adenotonsillectomy for OSAS , the Childhood Adenotonsillectomy Trial . METHODS : A total of 464 children who had OSAS ( average apnea/hypopnea index [ AHI ] 5.1/hour ) , aged 5 to 9.9 years , were r and omized to Early Adenotonsillectomy ( eAT ) or Watchful Waiting and Supportive Care ( WWSC ) .  Polysomnography and anthropometry were performed at baseline and 7-month follow-up . Multivariable regression modeling was used to predict the change in weight and growth indices . RESULTS : Interval increases in the BMI z score ( 0.13 vs 0.31 ) was observed in both the WWSC and eAT intervention arms , respectively , but were greater with eAT ( P < .0001 ) . Statistical modeling showed that BMI z score increased significantly more in association with eAT after considering the influences of baseline weight and AHI . A greater proportion of overweight children r and omized to eAT compared with WWSC developed obesity over the 7-month interval ( 52 % vs 21 % ; P < .05 ) . Race , gender , and follow-up AHI were not significantly associated with BMI z score change . CONCLUSIONS : eAT for OSAS in children results in clinical ly significant greater than expected weight gain , even in children overweight at baseline . The increase in adiposity in overweight children places them at further risk for OSAS and the adverse consequences of obesity . Monitoring weight , nutritional counseling , and encouragement of physical activity should be considered after eAT for OSAS BACKGROUND Adenotonsillectomy is commonly performed in children with the obstructive sleep apnea syndrome , yet its usefulness in reducing symptoms and improving cognition , behavior , quality of life , and polysomnographic findings has not been rigorously evaluated . We hypothesized that , in children with the obstructive sleep apnea syndrome without prolonged oxyhemoglobin desaturation , early adenotonsillectomy , as compared with watchful waiting with supportive care , would result in improved outcomes . METHODS We r and omly assigned 464 children , 5 to 9 years of age , with the obstructive sleep apnea syndrome to early adenotonsillectomy or a strategy of watchful waiting .  Polysomnographic , cognitive , behavioral , and health outcomes were assessed at baseline and at 7 months . RESULTS The average baseline value for the primary outcome , the attention and executive-function score on the Developmental Neuropsychological Assessment ( with scores ranging from 50 to 150 and higher scores indicating better functioning ) , was close to the population mean of 100 , and the change from baseline to follow-up did not differ significantly according to study group ( mean [ ±SD ] improvement , 7.1±13.9 in the early-adenotonsillectomy group and 5.1±13.4 in the watchful-waiting group ; P=0.16 ) . In contrast , there were significantly greater improvements in behavioral , quality -of-life , and polysomnographic findings and significantly greater reduction in symptoms in the early-adenotonsillectomy group than in the watchful-waiting group . Normalization of polysomnographic findings was observed in a larger proportion of children in the early-adenotonsillectomy group than in the watchful-waiting group ( 79 % vs. 46 % ) . CONCLUSIONS As compared with a strategy of watchful waiting , surgical treatment for the obstructive sleep apnea syndrome in school-age children did not significantly improve attention or executive function as measured by neuropsychological testing but did reduce symptoms and improve secondary outcomes of behavior , quality of life , and polysomnographic findings , thus providing evidence of beneficial effects of early adenotonsillectomy . ( Funded by the National Institutes of Health ; CHAT Clinical Trials.gov number , NCT00560859 . ) OBJECTIVES : Children with nonsevere obstructive sleep apnea ( OSA ) benefit from alternative therapeutic interventions such as leukotriene modifiers . We hypothesized that montelukast might improve OSA in children . We tested this hypothesis in a double-blind , r and omized , placebo-controlled fashion . METHODS : Of 50 possible c and i date s , we recruited 46 children with polysomnographically diagnosed OSA . In this prospect i ve , double-blind , r and omized trial , children received daily oral montelukast at 4 or 5 mg ( < 6 or > 6 years of age , respectively ) or placebo for 12 weeks . Polysomnographic assessment s , parent question naires , and radiographs to assess adenoid size were performed before and after therapy . RESULTS : Compared with the 23 children that received placebo , the 23 children that received montelukast showed significant improvements in polysomnographic measures of respiratory disturbance ( obstructive apnea index ) , children 's symptoms , and adenoid size . The obstructive apnea index decreased by > 50 % in 65.2 % of treated children . No attrition or side effects occurred . CONCLUSIONS : A 12-week treatment with daily , oral montelukast effectively reduced the severity of OSA and the magnitude of the underlying adenoidal hypertrophy in children with nonsevere OSA Objectives : To evaluate the impact of adenotonsillectomy ( T&A ) on quality -of-life ( QOL ) and behavior in obese versus normal-weight children with Obstructive Sleep Apnea ( OSA ) . Design : Prospect i ve , non-r and omized , controlled study . Methods : Children with an apnea-hypopnea index ( AHI ) ≥2 were studied . Polysomnography was performed before and after T&A. An age- and gender-specific body mass index ( BMI -for-age ) percentile was determined preoperatively . Children who were obese ( > 95th percentile ) were compared to normal-weight children ( BMI -for-age > 5th–85th percentile ) . Caregivers completed the OSA-18 QOL survey and the Behavioral Assessment Survey for Children ( BASC ) before surgery and 3–6 months postoperatively . Pre- and postoperative scores were compared using paired t-tests , and the impact of covariants was analyzed using ANOVA . Results : The study population consisted of 89 children , 40 of whom were obese ( 45 % ) . Postoperative scores for AHI , OSA-18 total and domain scores , and BASC scales and composites were significantly lower ( improved ) compared to pre-operative values in all children ( p < .001 ) . All mean OSA-18 and BASC scores were higher ( indicating worse quality -of-life and behavior ) pre- and postoperatively in obese than in normal-weight children . Postoperatively , the majority of OSA-18 total scores and domain scores were significantly higher in obese children . A comparison of the total OSA-18 scores between children with a postoperative AHI < 2 and A 
    Output:
    
In the CHAT trial , at seven months , neurocognitive performance and attention and executive function had not improved with surgery : scores were similar in both groups .
In otherwise healthy children , without a syndrome , of older age ( five to nine years ) , and diagnosed with mild to moderate OSAS by PSG , there is moderate quality evidence that adenotonsillectomy provides benefit in terms of quality of life , symptoms and behaviour as rated by caregivers and high quality evidence that this procedure is beneficial in terms of PSG parameters .
At the same time , high quality evidence indicates no benefit in terms of objective measures of attention and neurocognitive performance compared with watchful waiting .
Furthermore , PSG recordings of almost half of the children managed non-surgically had normalised by seven months , indicating that physicians and parents should carefully weigh the benefits and risks of adenotonsillectomy against watchful waiting in these children .