To evaluate the underlying clinical subtypes of obstructive sleep apnea (OSA) and its clinical characteristics by cluster analysis, and discuss possible differences in the presence of low arousal threshold between subtypes.

This is a cross-sectional study, and a non-random sampling method was used.A total of 154 OSA patients who visited the Sleep Monitoring Center of Peking Union Medical College Hospital from February 2020 to January 2022 were enrolled, there were 20 main manifestation and 6 comorbidities in those patients, the cluster analysis were performed by 2 assessment scales.The clinical characteristics and low arousal threshold between groups were compared.

All patients were divided into 3 groups by cluster analysis: sleep disorder group (37 cases, 24.02%), daytime sleepiness group (49 cases, 31.82%) and mild symptom group (68 cases, 44.16%). In the sleep disorder group, difficulty falling asleep and sdubjective negatively affecting sleep quality were more common; the Pittsburgh Sleep Quality Index (PSQI) score was significantly higher compared with the other two groups, and the sleep efficiency was lower than the daytime sleepiness group, and the differences were statistically significant (P<0.05); 48.65% of them had low arousal threshold.In the daytime sleepiness group, the prominent sleepiness symptoms was main manifestation, the Epworth Sleepiness Scale (ESS) score and polysomnography (PSG) index were significantly higher (all P<0.05); the lowest percentage of patients with low arousal threshold was present (32.65%). In the mild symptom group, the incidence of various symptoms, ESS score and PSQI score were significantly lower than those in the other two groups (P<0.05). The possibility in the presence of low arousal threshold was higher (54.41%), but there was no significant difference in low arousal threshold between the mild symptom group and the sleep disorder group (P>0.05). There was no significant difference in the complication among the three groups (all P>0.05).

Cluster analysis showed the clinical characteristics of OSA patients in different group, and there were differences in arousal thresholds between groups, which was helpful to further guide individualized treatment based on the characteristics of patients with different subtypes of OSA.

Sleep apnea, obstructive; Cluster analysis; Clinical subtypes; Disease characteristics; Low arousal threshold