Overview
Dysphagia is a commonly reported complaint among patients with obstructive sleep apnea (OSA), particularly those who have undergone upper-airway (oropharyngeal) surgery. However, how surgical treatment for OSA affects swallowing function and oral function (oral frailty) remains unclear.
This prospective cohort study recruits adults with moderate-to-severe OSA from the sleep medicine clinic of Kaohsiung Armed Forces General Hospital, Taiwan. Participants choose their own treatment as part of routine care; the study does not assign or influence treatment. Participants who undergo OSA surgery form the surgery group, and those who receive non-surgical treatment (e.g., CPAP) or no treatment form the non-surgical group. Swallowing difficulty (EAT-10) and oral frailty (seven oral hypofunction indicators) are assessed before treatment and at 1, 3, and 6 months after treatment.
Description
Background: Obstructive sleep apnea (OSA) is one of the most prevalent non-communicable diseases worldwide. Impaired swallowing reflex, pharyngeal sensory deficits and dysphagia have been reported in 16-78% of patients with OSA, and oropharyngeal surgery (e.g., uvulopalatopharyngoplasty) may further alter swallowing physiology. Oral frailty, a cluster of declines in oral function, is associated with dysphagia, physical frailty and mortality, yet it has not been examined in surgically treated OSA patients.
Design: Prospective observational cohort study. This registration covers Phase 2 of a two-phase project; Phase 1 is a separate retrospective analysis of Taiwan's National Health Insurance Research Database (2001-2020) comparing the incidence of dysphagia between OSA patients and matched non-OSA controls.
Participants: Adults aged 20 years or older with moderate-to-severe OSA (apnea-hypopnea index \>= 15 events/hour) who intend to receive next-step treatment. The target sample size is 450 (surgery group 225; non-surgical/no-treatment group 225), estimated with G\*Power (exact test; p1 = 0.16, p2 = 0.05, power = 0.95, allocation ratio 1:1).
Exposure: Surgical treatment chosen by the patient, such as radiofrequency reduction of the soft palate or tongue base, palatine tonsillectomy, uvulopalatopharyngoplasty (UPPP), CO2 laser-assisted uvulopalatoplasty (LAUP), transoral robotic surgery (TORS) and other upper-airway procedures. Treatment decisions are made by patients and their physicians; the study only records the treatment received.
Assessments (T0 before treatment; T1, T2 and T3 at 1, 3 and 6 months after treatment): Eating Assessment Tool-10 (EAT-10); oral frailty assessed by the seven oral hypofunction indicators (Minakuchi et al., 2018): tongue coating index, Saxon test, oral diadochokinesis (/pa/, /ta/, /ka/), number of natural teeth, tongue pressure (Iowa Oral Performance Instrument), self-reported masticatory ability, and the repetitive saliva swallowing test (RSST). Covariates include demographics, anthropometrics, blood pressure, comorbidities, smoking, alcohol use, exercise, prior oropharyngeal surgery, fatigue and OSA severity (AHI).
Analysis: Descriptive statistics will summarize treatment choices and baseline characteristics; between-group differences will be compared; repeated-measures analysis will compare changes in dysphagia and oral frailty between the surgery and non-surgical groups over 6 months.
Eligibility
Inclusion Criteria:
- Diagnosed by a physician with moderate-to-severe obstructive sleep apnea (apnea-hypopnea index \>= 15 events/hour)
- Aged 20 years or older
- Willing to receive next-step treatment for obstructive sleep apnea
- Willing to participate and provides written informed consent
Exclusion Criteria:
- Diagnosed with central sleep apnea
- Neuromuscular disease (e.g., stroke, Parkinson's disease)
- Diagnosed with oral cancer and currently receiving oral treatment


