Association of palatine tonsil size and obstructive sleep apnea in adults.

Objective: The relationship between palatine tonsil (PT) size and obstructive sleep apnea (OSA) has not been well established in adults. The purpose of this study was to test the association between PT grade, PT volume, and OSA severity in U.S. adult patients.

Study Design: Cross-sectional study of all patients (age ≥ 18 years) who underwent pharyngeal surgery for OSA that included palatine tonsillectomy with tonsil volume measurement from January 2011 to June 2016.

Methods: Medical records were reviewed for PT grade (measured on clinical exam by the Brodsky tonsil grading scale), PT volume (measured intraoperatively by water displacement), and apnea-hypopnea index (AHI). Associations were evaluated with multivariate linear regression adjusting for age, sex, body mass index (BMI), smoking status, lingual tonsil volume (AHI models only), and multilevel surgery aside from lingual tonsillectomy (PT volume vs. AHI model only).

Results: The cohort (N = 83) was middle-aged (mean age 43 ± 12 years), predominantly male (61%), obese (mean BMI 33 ± 7 kg/m ), and had severe OSA (mean AHI 32 ± 28). After adjustment for confounders, PT grade was strongly associated with PT volume (beta = 1.8, 95% confidence interval [CI]: [1.0, 2.6], P < 0.001) and with AHI (beta = 13.5, 95% CI: [3.5, 23.6], P = 0.01); PT volume was not associated with AHI (beta = -0.2, 95% CI: [-2.2, 1.9], P = 0.89).

Conclusion: In contrast to past studies, subjective PT grade (vs. objective PT volume) was more strongly associated with AHI. These data suggest the space that the tonsils occupy within the oropharyngeal airway, instead of their actual measured volume, may be more predictive of OSA severity in a cohort of U.S. adult patients.

Level Of Evidence: 2c. Laryngoscope, 128:1002-1006, 2018.