Fatigue is distinct from sleepiness and negatively impacts individuals living with obstructive sleep apnea (OSA): results from qualitative research of individuals with OSA.

BACKGROUND

We sought to identify important issues regarding symptoms and impacts of obstructive sleep apnea (OSA), to explore fatigue and sleepiness, and evaluate the content, clarity, and relevance of specific patient reported outcome (PRO) measures.

METHODS

Participants in the US with OSA and at least mild fatigue were studied. Individuals with positive airway pressure (PAP) therapy intolerance or current PAP refusal (non-PAP users) and those who initiated PAP within the past 12 months (PAP users) were identified and interviewed. Interviews included concept elicitation questions about symptoms and impacts of OSA. Participants then completed several PRO measures (the PRO Measurement Information System [PROMIS] Fatigue-8a, PROMIS Sleep-Related Impairment-8a, Epworth Sleepiness Scale [ESS], Patient-Global Impression of Severity of Fatigue [PGI-S Fatigue], and Patient Global Impression of Change in Fatigue [PGI-C Fatigue]) and were cognitively debriefed to evaluate their content, clarity, and relevance.

RESULTS

A total of 30 individuals with OSA (20 non-PAP and 10 PAP) were enrolled. In addition to fatigue (reported by 100%), sleepiness (75%), difficulty concentrating (85%), dry mouth/throat (60%), headaches (50%) and interrupted sleep (50%) were the most common symptoms reported by non-PAP users. Fifty-eight percent of non-PAP users rated fatigue as the most bothersome symptom; 5% rated sleepiness as the most bothersome. Among PAP users, the most common symptoms (prior to PAP use) in addition to fatigue (100%) were sleepiness (90%), difficulty concentrating (60%), dry mouth/throat (60%), headaches (50%), and interrupted sleep (50%). Fatigue was rated as most bothersome by 56% of PAP users; sleepiness was rated as the most bothersome by 22%. All participants mentioned fatigue and sleepiness separately, indicating they are considered distinct symptoms. In general, participants found the PRO measures to be relevant and clear, and results supported their content validity, clarity, and relevance.

CONCLUSIONS

Fatigue was the most bothersome symptom reported by non-PAP and PAP users. Participants described fatigue as a distinct and different concept from excessive daytime sleepiness. Participants reported that their OSA symptoms negatively impact daily activities, functioning, work, and relationships. The PRO measures are clear and relevant for individuals with OSA and appropriate for use in both clinical and research settings.