Cephalometric, muscular and swallowing changes in patients with OSAS

Abstract

Obstructive Sleep Apnoea Syndrome (OSAS) is believed to be associated with craniofacial and neuromuscular changes, although the interplay among these variables still is poorly recognised. The objective of this study was to identify hyoid, muscular and swallowing changes associated with OSAS, and to correlate these alterations with OSAS severity. Cross-sectional study, in a tertiary referral centre. Seventy-two adult individuals participated in this study: 12 controls (without apnoea) and 60 patients with apnoea (mild, moderate and severe OSAS-20 individuals in each group). All participants were initially evaluated by otorhinolaryngologist and neurologist and underwent polysomnography for OSAS stratification. Cephalometric data, clinical myofunctional status and swallow videofluoroscopy exam were assessed. A hybrid effect model was used to analyse swallowing parameters; dependent variables were age, body mass index (BMI) and cephalometric measures. Individuals with OSAS presented lower hyoid position and narrower posterior airway distance when compared to controls. These parameters correlated to OSAS severity. Additionally, OSAS patients exhibited significantly lower myofunctional scores. Both velum and hyoid contraction times were significantly lower in the OSAS group at videofluoroscopy, regardless of its severity. Premature leakage into pharynx was more common in OSAS groups. Laryngeal penetration phenomenon occurred only in two patients (both from OSAS group). Our results suggest that hyoid bone position is associated with OSAS severity. Muscular pattern and swallowing are impaired in OSAS patients, irrespective of OSAS severity and facial profile. These findings indicate a higher predisposition of OSAS patients to present an inferior hyoid positioning, accompanied by myofunctional and swallowing disorders.

Relation between acoustic analysis of swallowing and the presence of pharyngeal residue and penetration/aspiration in resistant hypertensive patients with obstructive sleep apnea

“…A possible explanation is that the time reduction of the pharyngeal phase reduces the time of one or more events of this phase (UES opening time, for example) what may result in pharyngeal residue. Strengthening this hypothesis, a study revealed that the support time of hyoid bone excursion, considered an important mechanism to maintain UES opening, was significantly shorter in individuals with OSA compared with control group 7 . In addition, considering the GERD risk in this population 38 , researchers point out that the duration of cricopharyngeal muscle relaxation during swallowing, an important mechanism for UES opening 30 , is shorter in individuals with mild GERD compared with individuals without GERD 40 .…”

“…The apnea-hypopnea index (AHI) was calculated as the number of events of apneahypopnea by hour of sleep. OSA severity was defined as mild (AHI: [5][6][7][8][9][10][11][12][13][14], moderate (AHI: 15-30) and severe (AHI >30).…”

“…Recent studies show that individuals with OSA may present oropharyngeal dysphagia, reducing safety and efficacy of swallowing, thus, exhibiting penetration/ aspiration [4][5][6][7] and pharyngeal residue 4,5,8,9 . The methods considered gold standard to evaluate swallowing are videofluoroscopic swallowing study (VFSS) and fiberoptic endoscopic evaluation of swallowing (FEES) 10 , although both present some disadvantages and restrict access to the great majority of Brazilian population.…”

Relation between oro‐facial thermographic findings and myofunctional characteristics in patients with obstructive sleep apnoea

“…Evaluating the temperature of the submental triangle region (suprahyoid muscle region) can be of clinical interest, as the lower temperatures found in patients with OSA can be associated with the hypofunction of the suprahyoid muscle, 9,35 with consequent reduction in the perfusion of these muscles, and downward positioning of the hyoid bone 9,35 . Another hypothesis for this finding is the slightly higher BMI and neck circumference, associated with a higher fat accumulation in the neck, 36,37 making this region hyporadiant as the high fat tissue acts as an insulating barrier that interferes with heat transfer through the skin and the body's responses to changes in environmental temperature 38 …”

Orofacial functions and forces in male and female healthy young and adults

“…Some diseases as dentofacial deformities (2) , temporomandibular disorder (3,4) , obstructive sleep apnea (5) have associated orofacial functions impairment.…”