At the ESC Congress 2014 in Barcelona, ResMed announced results from a study that looked at the use of the at-home, contactless, bedside SleepMinder device to diagnose sleep-disordered breathing. Sleep-disordered breathing (SDB) is the most common comorbidity in patients with heart failure (HF).1,2
The study assessed how SleepMinder, when used over 2 weeks, compared to a current gold standard of diagnosis, a single night assessment via inpatient polysomnography (PSG). The investigating team reported that, after using SleepMinder for 2 weeks, 57% of patients were consistently above a threshold that would require treatment for their SDB (AHI ?15). This rose to 74% in patients who were followed up for 12 months.1
“Sleep-disordered breathing is the most common heart failure co-morbidity, yet the diagnosis is often missed,” says Martin Cowie, professor of cardiology, Royal Brompton Hospital, London, and co-author of the study, in a release. ”This condition affects millions of heart failure patients across Europe and can lead to significantly worse outcomes if not correctly diagnosed and treated. This study showed that, by using a device that can gather longer-term data, we can offer a means of diagnosis that is both practical for patients, doctors, and health services and may well be more accurate than existing techniques that require inpatient care. It is vital that cardiologists explore how they can help to establish more routine use of this technology in the heart failure patient pathway.”
SDB is typically diagnosed in patients with HF by calculating the AHI, typically from a single overnight PSG study conducted in a hospital or specialist sleep center. However, HF patients commonly experience volume load changes that can make AHI highly variable in this population over time. Mean AHI assessment, over a longer period, is therefore likely to be more accurate.1 SleepMinder is a noncontact, bedside, nocturnal respiratory monitor that can be placed next to a patient’s bed to collect data on SDB over longer periods. Two weeks represent a useful period for SDB assessment to be gathered. This study involved 39 adult patients with HF who were assessed over 12 months. Following 2 weeks of assessment, mean AHI was consistently above the treatment threshold for 57% of patients. This rose to 74% after 12 months of follow-up.1
These results can have significant implications for the routine diagnosis of this prevalent condition in HF.
SDB is the most common comorbidity in HF, affecting between 50% and 75% of the 15 million HF patients in Europe.3-5 However, it remains underdiagnosed and one of the least recognized comorbidities by cardiologists, despite being linked to worse outcomes including mortality, hospitalizations, and quality of life.6
In an additional study, presented at a Rapid Fire session, data were presented highlighting that treating cardiac patients with SDB with PAP device therapy could reduce 3-year mortality by up to 38%.7 In patients with coronary heart disease (CHD) or HF, 3-year mortality was reduced by 37.9% (4.5% vs 7.2%; p=0.0002) and 31.6% (14.7% vs 21.4%; p<0.0001), respectively, highlighting the importance of correct diagnosis and treatment of this prevalent comorbidity.7
The analysis assessed outcomes for a total of >4 million individuals covered by the German Statutory Health Insurance (SHI) database (approximately 5% of the German SHI population). PAP therapy was initiated in 4,068 patients with sleep apnea. Propensity score was used to define a control group of equal number who received usual care (no PAP).7
A common type of SDB, CSA-CSR, can be successfully treated with PaceWave Adaptive Servo-Ventilation (ASV) therapy. In 2013, ResMed completed enrollment of the 1,325th patient in SERVE-HF, the world’s largest randomized study investigating by what degree the treatment of central SDB (central sleep apnea) with PaceWave ASV may improve survival and outcomes of patients with stable HF. Results are expected in 2015 and could lead to significant changes in cardiology clinical practice.
References
1. Savage H, et al. The Mean Apnoea Hypopnea Index as a Diagnostic Criterion for Sleep Disordered Breathing in Patients with Heart Failure. ESC Congress 2014, abstract FP# P2758 – presented 31 August 2014.
2. Javaheri. Basics of Sleep Apnoea and Heart Failure. Sleep Apnoea and CV Disease – A CardioSource Clinical Community. Available online at http://apnea.cardiosource.org/Basics/2013/02/Basics-of-Sleep-Apnea-and-Heart-Failure.aspx (last accessed, August 2014).
3. Dickstein K, et al. ESC guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur J Heart Fail. 2008;10:933-89. doi: 10.1016/j.ejheart.2008.08.005.
4. Oldenburg O, Lamp B, Faber L, Teschler H, Horstkotte D, Topfer V. Sleep-disordered breathing in patients with symptomatic heart failure: a contemporary study of prevalence in and characteristics of 700 patients. Eur J Heart Fail. 2007;9:251–257. [PubMed]
5. Schulz R, Blau A, Börgel J, et al; working group Kreislauf und Schlaf of the German Sleep Society (DGSM). Sleep apnoea in heart failure. Eur Respir J. 2007;29:1201–1205. [PubMed]
6. Javaheri. Basics of Sleep Apnoea and Heart Failure. Sleep Apnoea and CV Disease – A CardioSource Clinical Community. Available online at http://apnea.cardiosource.org/Basics/2013/02/Basics-of-Sleep-Apnea-and-Heart-Failure.aspx (last accessed, August 2014).
7. Woehrle H, et al. Benefit of positive airway pressure (PAP) therapy in patients with sleep apnoea (SA) in Germany: a retrospective comparative cohort analysis based on a statutory health insurance (SHI) database. ESC Congress 2014, abstract 90918 – presented as part of the Rapid Fire session on 31 August 2014.
