Increased body mass index percentile, younger age at primary intervention, allergic rhinitis, and adenoidectomy without tonsillectomy may increase the risk of requiring a secondary adenoidectomy, according to a new longitudinal cohort study published in the American Journal of Otolaryngology–Head and Neck Medicine and Surgery.
Researchers collected data from 461 patients at a tertiary pediatric hospital who underwent adenoidectomy from January 2015 to January 2016 and had two years of postoperative follow-up. They analyzed demographic, surgical, and clinical data using logistic and Cox regression models to identify factors affecting the likelihood and timing of revision adenoidectomy.
Of the 461 patients, 115 (25%) had obesity at primary intervention. Secondary intervention was performed for 136 patients (30%), with a median interval of 29 months between procedures. The revision rate was notably higher than the 1% to 3% typically reported in comparable studies, which the authors attributed to the medically complex patient population. For instance, 35% of patients had gastroesophageal reflux disease (GERD) and 46% had allergic rhinitis, compared with rates of less than 1% and 2%, respectively, in other studies.
In the logistic regression, adenotonsillectomy reduced the odds of revision by 70% compared with adenoidectomy alone. In the Cox regression, hazard was lower with adenotonsillectomy, older age at initial surgery, and GERD, but higher with laryngomalacia or tracheomalacia. Body mass index (BMI) percentile was not associated with revision timing in the Cox model.
Among patients who underwent revision, BMI percentile was statistically significantly higher at the time of secondary intervention (66) compared with primary intervention (62). A longer interval between procedures was also associated with increased BMI percentile at secondary intervention.
Inflammation may be a confounding variable linking obesity and adenoid hypertrophy, the researchers noted. Prior studies have shown that elevated levels of interleukin-32, a proinflammatory cytokine, can precipitate or worsen adenoid hypertrophy, and that patients with obesity express increased levels of this cytokine in adipose tissue.
"These findings support the potential role of obesity-related inflammation in adenoid hypertrophy and individualized surgical decision-making in pediatric patients with sleep disordered breathing," wrote lead study author Liliana Arida-Moody of Vanderbilt University School of Medicine, and colleagues.
The study's limitations included selection bias due to the two-year follow-up requirement, which resulted in losing 1,410 patients from the original cohort of nearly 2,000. Results may not be generalizable to the typical pediatric population but may inform care for patients with comorbidities.
The researchers reported no conflicts of interest. The study received no specific funding.