da Rocha M, et al. - This research dealt with the appraisal of the evolution of polysomnographic parameters among children with Down syndrome and obstructive sleep apnea syndrome submitted to adenotonsillectomy along with the interaction of comorbidities on therapeutic outcome. An improvement was reported in the symptoms and objective sleep data in children with Down syndrome via adenotonsillectomy. However, it was not able to resolve obstructive sleep apnea syndrome in a majority of the patients. Congenital heart diseases and hypothyroidism could exert an impact on the outcome.