Pediatric obstructive sleep apnea - evaluation of questionnaire and surgical treatment

Sammanfattning: Obstructive sleep apnea (OSA) is a major pediatric health problem and is associated with potentially severe consequences if left untreated. Diagnosing OSA in children can be challenging since the clinical symptoms are very non-specific. A full-night polysomnography is recommended as the gold standard to establish the diagnosis, but it is not possible to perform this for every child where suspicion of OSA has arisen. Other diagnostic instruments such as questionnaires have been used, and one of these, the OSA-18, was evaluated in Paper I. The dominant cause of OSA in children is tonsil hypertrophy and treatment is surgical with removal of tonsils. Tonsillectomy is one of the most common surgical procedures performed on children throughout the world. The trends of Swedish tonsil surgery in recent decades were described in Paper II. In recent years, tonsillotomy (partial tonsillectomy) has gained popularity as an option for surgery in Sweden. It has been unclear whether tonsillotomy is as effective as tonsillectomy in treating OSA, and this was investigated in a randomized study. The overall aim of the thesis was to contribute to the improvement of the diagnostic process and surgical treatment of OSA for children. Paper I considers the diagnostic process of pediatric OSA and evaluates the disease-specific questionnaire OSA-18. 225 children were included. They all performed a full-night PSG and their parents responded to OSA-18. The scores of the OSA-18 were compared to the apneahypopnea index from PSG, and the results showed poor predictivity of the OSA-18 to detect and correctly grade the severity of OSA. Paper II is a longitudinal description of the trends in the clinical practice of tonsil surgery in Sweden between 1987 and 2013. The study was based on the Swedish National Patient Register, and all children aged 1-17 years who were registered with a tonsil surgery procedure were included, totaling 167 894 individuals. The results demonstrated substantial shifts in the trends of tonsil surgery over the period, with an overall increase in incidence of tonsil procedures, consisting mainly of tonsil surgery due to sleep disordered breathing/OSA, especially among the youngest children (1-3 years). Moreover, a gradual increase in the incidence of tonsillotomy since it was introduced in the late 1990s was observed, and since 2011 tonsillotomy has been more common than tonsillectomy. Papers III and IV are a randomized trial with the aim of comparing adenotonsillotomy (ATT) with adenotonsillectomy (ATE) regarding the effect of treating pediatric OSA measured by polysomnography(Paper III). The RCT included 79 children aged 2-6 years, with moderate to severe OSA, randomized to either ATT or ATE. All children performed a PSG at baseline, with follow-up one year after surgery. Paper III primarily evaluated the polysomnographic outcomes, showing that ATT was non-inferior to ATE. However, five cases in the ATT-group needed repeated surgery due to re-growth of tonsils and return of OSA-symptoms, and thus considered as failures of ATT. All children were also evaluated concerning postoperative pain and bleeding (Paper IV), showing that ATT is associated with less postoperative pain than ATE, but the differences were modest. Two cases of postoperative bleeding were seen in the ATE group and no cases of postoperative bleeding in the ATT group, indicating a lower risk of bleeding after ATT than ATE, but a larger study population would have been needed for better evaluation.