East, West: is home best?

Watch-PAT versus level III device in diagnosing sleep disordered breathing in first myocardial infarction

BACKGROUND

Watch-PAT 200, a novel portable sleep device worn on the wrist, has been validated against polysomnography. Although sleep disordered breathing (SDB) screening is recommended in patients with cardiovascular disease, no study has reported a comparison of results from Watch-PAT 200 and level III portable devices.

METHODS

Patients (n = 140) admitted with a first ST-segment elevation myocardial infarction (STEMI) participated in a hospital-based sleep study using the Watch-PAT 200 and a level III portable device (Embletta Gold) simultaneously within five days of admission. SDB was defined as an apnea-hypopnea index (AHI) of >15 events/h.

RESULTS

The left ventricular ejection fraction was normal (≥50%), impaired (30%-49%) and poor (<30%) in 66 (47.1%), 71 (50.7%), and three (2.2%) patients, respectively. Among 116 patients with a successful paired sleep study, the prevalence of SDB was 53.5% (Watch-PAT 200) and 51.7% (Embletta Gold). The agreement of AHI measured by the two devices was moderately good, with an intra-class correlation value of 0.72 (95% confidence interval, 0.62-0.80; P < .01). Agreement between the two devices in diagnosing at least mild (AHI ≥5), moderate-to-severe (AHI ≥15) and severe (AHI ≥30) SDB was 78% (kappa 0.47; P < .01), 77% (kappa 0.55; P < .01) and 80% (kappa 0.49; P < .01), respectively. At a 15-month follow-up, SDB status based on the two devices was associated with the occurrence of adverse cardiovascular events in 48.3% and 44.8%, respectively (P = .56).

CONCLUSION

We found a high prevalence of SDB in patients presenting with a first STEMI. Agreement between two portable sleep devices was moderately good.