A study of children younger than 3 years of age with obstructive sleep apnea (OSA) suggests that many of them will have residual OSA after adenotonsillectomy (T & A) intended to treat it, according to a study by Andrea Nath, M.D., and colleagues at the University of Chicago.

OSA is a form of sleep-disordered breathing estimated to affect 2 to 3 percent of children. Predictors of persistent OSA after T & A surgery in younger children have not been well studied according to the study background. Researchers reviewed medical records to study residual OSA in children younger than 3 years after T & A surgery, and sought to identify predictors of residual disease.

The study included 283 patients (average age 22 months) who underwent a preoperative polysomnogram (PSG), 70 of whom also had a postoperative PSG.

In the group that had both PSGs, there were improvements in mean apnea hypopnea index (AHI, which measures the severity of the condition), baseline oxygen saturation, minimum oxygen saturation and sleep efficiency, the results indicate. However, 21 percent of the patients (15 of 70) had residual OSA, defined as an AHI greater than 5. Residual OSA appeared to be associated with the severity of preoperative OSA, according to the results.

"Our data support the finding that, although T & A leads to a dramatic improvement in this age group, a high proportion of this population will have residual OSA. Although this proportion gives some insight into residual disease after T & A in this young population, the result is flawed because of the retrospective design of the study and the fact that only 25 percent of the children treated received postoperative PSGs," the study concludes. "Future research should focus on prospective evaluation of a large cohort of younger children with OSA for whom the extent of the disease is documented preoperative and postoperatively."