Characterization of Patients With Obstructive Sleep Apnea Syndrome Undergoing Drug-Induced Sleep Endoscopy: A Retrospective Study of Nine Years (2014-2022).

Introduction:  Obstructive sleep apnea syndrome (OSAS) is the most prevalent sleep-related breathing disorder associated with an increased risk of cardiovascular and cerebrovascular complications. Identifying the anatomical sites of airway obstruction is crucial for optimizing treatment, particularly in patients requiring surgical intervention. In recent years, drug-induced sleep endoscopy (DISE) has emerged as a valuable diagnostic tool for evaluating upper airway obstruction in OSAS patients.

Objectives: To characterize the OSAS population undergoing DISE and correlate endoscopic findings with patient characteristics and obstruction sites.

Materials And Methods:  A retrospective study was conducted by reviewing medical records of patients who underwent DISE between 2014 and 2022 at Hospital da Senhora da Oliveira, Guimarães. The analyzed variables included age, gender, body mass index (BMI), apnea-hypopnea index (AHI), and the level and pattern of obstruction based on the velum, oropharynx, tongue, and epiglottis (VOTE) classification. Statistical analysis was performed using IBM SPSS Statistics v27.0 (IBM Corp., Armonk, USA).

Results:  A total of 71 patients underwent DISE, with ages ranging from 25 to 68 years. The majority were male (84%, n=60). Regarding BMI distribution, 18.3% (n=13) of patients were classified as obese, 67.6% (n=48) as overweight, and 14.1% (n=10) had a normal weight. Most patients had moderate OSAS (56.3%, n=40), followed by severe (26.8%, n=19) and mild OSAS (16.9%, n=12). A significant positive correlation was observed between AHI and BMI (p=0.028). Multilevel obstruction was identified in 75% of patients, with the most common collapse site being the soft palate, followed by the oropharynx, base of the tongue, and epiglottis. No statistically significant differences were found in the obstruction site, pattern, or severity based on AHI or BMI. However, at the palatal level, a positive trend was observed between AHI and obstruction severity (r=0.153; p>0.05).

Conclusions:  DISE is a safe and reliable diagnostic modality for identifying upper airway collapse sites, revealing anatomical alterations that may not be apparent during standard physical examination. This technique plays a crucial role in evaluating patients considered for surgical intervention or those who have not responded to first-line therapies. DISE enables a personalized approach to OSAS management by tailoring treatment strategies to individual patient anatomy and obstruction patterns.