[Diagnostic accuracy of Epworth sleepiness scale in the acute phase of myocardial infarction].

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is underdiagnosed in cardiologist daily practice, especially in patients with acute coronary syndrome. Its diagnosis is based on a polysomnography study. The Epworth Sleepiness Scale (ESS) stands as a simple and rapid means to select patients for the sleep investigation.

AIM: The aim of this study was to determine the diagnostic accuracy of the ESS for screening OSAS in patients with ST elevation myocardial infarction.

METHODS: We conducted a prospective study of 120 consecutive patients admitted for acute myocardial infarction, from April 2011 to March 2012. Daytime sleepiness was evaluated using the ESS, when patients were in the intensive care unit. All patients have undergone an overnight sleep study using a portable diagnostic device, in the 15 days following the acute coronary syndrome. The diagnostic of OSA was considered as apnea-hypopnea index (AHI) of ≥5 events/hour, severe OSA was defined as AHI of ≥30.

RESULTS: The study included 120 patients comprising 102 men and 18 women. The mean age was 58 ± 12 years. Smoking was the major cardiovascular risk factor with 72% of all patients; prevalence of diabetes was 40% and hypertension was found in 44% of the population. The prevalence of OSA was 79%. Severe OSA was diagnosed in 16% of all patients and mean AHI was 15.76 ± 14.93. Mean ESS was 2.2 ± 1.84 in the global population while it was 5.2 ± 1.2 in patients with severe OSAS. Multivariate analysis showed that ESS score ≥ 4 was an independent predictive factor for severe OSA (OR=28; 95% IC: 8-101; P<0.001).

CONCLUSION: The prevalence of OSA in patients with acute myocardial infarction was very high. ESS score ≥ 4 was an independent predictive factor for severe OSA. Despite its subjective feature, the ESS seems to be an interesting score for screening patients to undergo polysomnography.