Prevalence of upper airway resistance syndrome in the São Paulo Epidemiologic Sleep Study

To establish the prevalence of upper airway resistance syndrome (UARS) according to different diagnostic criteria and evaluate its epidemiological characteristics in a representative sample of a large urban center.

This was a single-center evaluation involving volunteers from EPISONO, an epidemiological study focused on sleep disturbances and related factors in adults from São Paulo, Brazil in 2007.

Considering the diagnostic criteria for UARS to be an apnea-hypopnea index of <5 events/h, minimum SpO₂ ≥ 92%, the presence of airflow limitation during sleep for ≥5% of total sleep time, and daytime symptoms (sleepiness and/or fatigue), we observed a prevalence of the condition of 3.1% (4.4% in women and 1.5% in men).

Although the diagnostic criteria for UARS, or even its existence as a syndrome, are still a subject of debate in the literature, the findings from this epidemiological study highlights UARS as a non-hypoxic sleep-disordered breathing condition with a significant prevalence in the general population, being more frequent among female young adults.