September 27, 2023Open Access

Obstructive sleep apnea severity and prevalent atrial fibrillation in a sleep clinic cohort with versus without excessive daytime sleepiness

Q: What is the clinical evidence from this study?

Study design: Cross-Sectional. Population: Obstructive sleep apnea and atrial fibrillation (n=3814). Intervention: Severe obstructive sleep apnea without excessive daytime sleepiness vs. No obstructive sleep apnea. Primary outcome: Prevalent atrial fibrillation (OR 2.54, 95% CI 1.05-6.16, p=0.039).

Key Result

Severe obstructive sleep apnea without excessive daytime sleepiness was associated with an increased risk of prevalent atrial fibrillation (OR 2.54; 95% CI 1.05-6.16; p=0.039).

Study Design

Type

Cross-Sectional (n=3,814)

Multicenter

Structured PICO

Is obstructive sleep apnea severity associated with prevalent atrial fibrillation in a sleep clinic cohort with versus without excessive daytime sleepiness?

Population

3,814 consecutive adults admitted to a sleep clinic at Skaraborg Hospital, Sweden

Intervention

Obstructive sleep apnea (OSA) severity (mild, moderate, severe) stratified by excessive daytime sleepiness (EDS)

Comparator

No OSA

Outcome

Prevalent atrial fibrillation (AF)hard clinical

Severe obstructive sleep apnea is independently associated with prevalent atrial fibrillation in patients without excessive daytime sleepiness, highlighting a high-risk phenotype that may be challenging to treat due to lack of symptoms.

Main Result

Effect estimate: OR 2.54 (95% CI 1.05-6.16)

Absolute Event Rate: 7.6% vs 1.6%

p-value: p=0.039

Abstract

BACKGROUND: Obstructive sleep apnea (OSA) is associated with atrial fibrillation (AF) in cardiac cohorts. Less is known regarding the magnitude of this association in a sleep clinic cohort with vs. without excessive daytime sleepiness (EDS). OBJECTIVES: To explore the association of OSA severity with AF in a sleep clinic cohort stratified by EDS. PATIENTS AND METHODS: All consecutive adults (n = 3814) admitted to the Skaraborg Hospital, Sweden between Jan 2005 and December 2011 were registered in a local database, and the follow-up ended in December 2018. OSA was defined as an apnea-hypopnea index (AHI) ≥5 events/h. Mild OSA was defined as AHI ≥5 moderate OSA as AHI ≥15 and severe OSA as AHI ≥30 events/h. EDS was defined as an Epworth Sleepiness Scale score ≥11. We conducted cross-sectional analyzes of the prevalent AF across the OSA severity categories and logistic regression analyzes stratified by EDS. RESULTS: In all, 202 patients (5.3%) had AF at baseline, 1.6% in no-OSA, 3.9% in mild OSA, 5.2% in moderate OSA, and 7.6% in severe OSA, respectively (p < 0.001). The stratified analyzes revealed that patients with severe OSA without EDS had an increased risk for prevalent AF (OR 2.54, 95% CI 1.05-6.16; p = 0.039) independent of the confounding factors. CONCLUSIONS: There was an independent dose-response relationship between OSA and prevalent AF among the non-sleepy phenotype in this sleep clinic cohort. Since adherence to OSA treatment is challenging in the absence of EDS, these patients may have increased risk for adverse cardiovascular outcomes.