To evaluate the upper airway morphology changes associated with ageing in adult Chinese patients with obstructive sleep apnoea.

A total of 124 male patients diagnosed with obstructive sleep apnoea by overnight polysomnography, who underwent upper airway computed tomography, were enrolled. The linear dimensions, cross-sectional area and volume of the upper airway region and the surrounding bony frame were measured. The association between ageing and upper airway morphology was analysed.

Soft palate length, minimum cross-sectional area of the retroglossal region, lateral dimensions at the minimum cross-sectional area of the retropalatal and retroglossal regions, nasopharyngeal volume, and average cross-sectional area of the nasopharyngeal region were found to significantly increase with ageing in all patients, while the upper airway shape flattened with ageing. The volume of the retropalatal region increased with ageing among the patients with a body mass index of less than 24 kg/m2. The volume of parapharyngeal fat pad increased with ageing among patients with a body mass index greater than 28 kg/m2.

A number of dimensional, cross-sectional and volumetric parameters of the pharynx increased with age, indicating that non-anatomical factors may play a more important role in the pathogenesis of obstructive sleep apnoea in aged patients.

To investigate the neutrophil-to-lymphocyte ratio and sleep apnoea severity relationship.

Patients (n = 178) were assigned to five groups according to apnoea–hypopnea indices and continuous positive airway pressure use. White blood cell, neutrophil, lymphocyte and neutrophil-to-lymphocyte ratio values were compared for each group.

The neutrophil-to-lymphocyte ratio values of severe obstructive sleep apnoea syndrome patients (group 4) were significantly higher than those of: control patients (group 1), mild obstructive sleep apnoea syndrome patients (group 2) and patients treated with continuous positive airway pressure (group 5) (p = 0.008, p = 0.008 and p = 0.003). Minimum oxygen saturation values of group 4 were significantly lower than those of groups 1, 2 and 5 (p = 0.0005, p = 0.011 and p = 0.001). There was a positive correlation between apnoea–hypopnea index and neutrophil-to-lymphocyte ratio (r = 0.758, p = 0.034), and a negative correlation between apnoea–hypopnea index and minimum oxygen saturation (r = −0.179, p = 0.012).

Neutrophil-to-lymphocyte ratio may be used to determine disease severity, complementing polysomnography.