1. Screening for Obstructive Sleep Apnoea in Cardiac Rehabilitation – A Single Site Experience.
Robert Zecchin, Justine Thelander, Julie Hungerford, Gail Lindsay, Jan Baihn, Yeng Chai, Inga Saliba, A. Robert Denniss. Westmead Hospital NSW Australia

2. Background
Obstructive sleep apnoea (OSA) is an independent risk factor for coronary heart disease.
There is a paucity of knowledge of OSA screening in cardiac rehabilitation (CR) patients, especially in Australia.

5. Rehabilitation of Cardiovascular Disorders and Sleep Apnea.
Jafari B. Sleep Med Clin
Obstructive sleep apnea (OSA) is present in more than 50% of patients referred to cardiac rehabilitation units. However, it has been under-recognized in patients after stroke and heart failure. Those with concurrent OSA have a worse clinical course. Early treatment of coexisting OSA with continuous positive airway pressure (CPAP) results in improved rehabilitation outcomes and quality of life. Possible mechanisms by which CPAP may improve recovery include decreased blood pressure fluctuations associated with apnoea's, and improved left ventricular function, cerebral blood flow, and oxygenation. Early screening and treatment of OSA should be integral components of patients entering cardiac rehabilitation units.

7. Stephen Woodruffe et al. Heart, Lung and Circulation (2015)
Australian Cardiovascular Health and Rehabilitation Association (ACRA) Core Components of Cardiovascular Disease Secondary Prevention and Cardiac Rehabilitation 2014
Stephen Woodruffe et al. Heart, Lung and Circulation (2015)
4.9 Obstructive sleep apnoea
1. Sleep apnoea assessed with validated tool
2. Referral to GP/specialist as appropriate
= KPI - % patients referred to GP

8. Validation of the STOP-Bang Questionnaire as a Screening Tool for Obstructive Sleep Apnea among Different Populations: A Systematic Review and Meta-Analysis. Nagappa M et al. PLoS ONE 2015.
Results: Seventeen studies including 9,206 patients met criteria for the systematic review. In the sleep clinic population, the sensitivity was 90%, 94% and 96% to detect any OSA (AHI 5), moderate-to-severe OSA (AHI 15), and severe OSA (AHI 30) respectively. The corresponding NPV was 46%, 75% and 90%. A similar trend was found in the surgical population. In the sleep clinic population, the probability of severe OSA with a STOP-Bang score of 3 was 25%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability rose proportionally to 35%, 45%, 55% and 75%, respectively. In the surgical population, the probability of severe OSA with a STOP-Bang score of 3 was 15%. With a stepwise increase of the STOP-Bang score to 4, 5, 6 and 7/8, the probability increased to 25%, 35%, 45% and 65%, respectively.
Conclusion: This meta-analysis confirms the high performance of the STOP-Bang questionnaire in the sleep clinic and surgical population for screening of OSA. The higher the STOP-Bang score, the greater is the probability of moderate-to-severe OSA.

9. Screening Questionnaires for Obstructive Sleep Apnea:
An Updated Systematic Review Amra B, Rahmati B, Soltaninejad F, Feizi A.
Oman Med J
Thirty-nine studies comprising 18 068 subjects were included. Four screening questionnaires for OSA had been validated in selected studies including the Berlin questionnaire (BQ), STOP-Bang Questionnaire (SBQ), STOP Questionnaire (SQ), and Epworth Sleepiness Scale (ESS). The sensitivity of SBQ in detecting mild (apnea-hypopnea index (AHI) ≥ 5 events/hour) and severe (AHI ≥ 30 events/hour) OSA was higher compared to other screening questionnaires (range from 81.08% to 97.55% and 69.2% to 98.7%, respectively). However, SQ had the highest sensitivity in predicting moderate OSA (AHI ≥ 15 events/hour; range = 41.3% to 100%). SQ and SBQ are reliable tools for screening OSA among sleep clinic patients. Although further validation studies on the screening abilities of these questionnaires on general populations are required.

10. Michael R Le Grande et al. Eur J Prev Cardiol. 2016.
Screening for obstructive sleep apnoea in cardiac rehabilitation: A position statement from the Australian Centre for Heart Health and the Australian Cardiovascular Health and Rehabilitation Association
Michael R Le Grande et al. Eur J Prev Cardiol
Given the potential benefits of obstructive sleep apnoea treatment it would make sense to screen for this condition upon entry to out-patient cardiac rehabilitation programmes. A two-stage approach to screening is recommended, where patients are initially evaluated for the probability of having obstructive sleep apnoea using a brief questionnaire (The STOP-Bang) and then followed up with objective evaluation (portable home monitor or polysomnography) where necessary.

12. Methods
Consecutive patients who attended a CR program in Western Sydney who had OSA screening using the STOP-BANG questionnaire were included.
This study compared low risk (LOSA) and high risk (HOSA) patients for OSA in relation to socio-demographics, anthropometrics, functional capacity, risk factors, medications and quality of life (QOL) over an 18 month period (July Dec 2017).

13. Study characteristics
Study period
18 months
Patient’s screened (n=)
479
Mean Age (+/- SD)
61 +/- 13
Gender
80% male
LOSA/IOSA/HOSA
125 (26%) / 217 (45%) / 137 (29%)
LOSA with OSA before CR
1 (<1%)
HOSA with OSA before CR
25 (24%)
LOSA = Low Risk OSA,
IOSA = Intermediate Risk OSA,
HOSA = High Risk OSA
CR = Cardiac Rehabilitation

14. Baseline differences between LOSA and HOSA
P-value
Age (years +/- SD)
57 +/- 17
62 +/- 10
<0.01
Gender (Male; %)
60%
91%
Weight (Kg)
71 +/- 13
93 +/- 17
<0.001
Waist circumference (cm)
93 +/- 10
110 +/- 13
BMI (kg/m2)
25.7
31.6
Atrial Fibrillation/Flutter 2%
10%

15. Baseline differences between LOSA and HOSA
P-value
Risk Factors:
Diabetes
22%
39%
0.002
Hypertension
30%
76%
<0.0001
Smoking
19%
20% NS
Hyperlipidaemia
84%
94%
Medication:
Digoxin 2% 7%
0.03
ACE/ARB
49%
67%
0.003
Beta-Blockers
71%
74%
Ca Channel Blockers 8%
18%
0.01
QOL (SF-36)
Physical Functioning 65 56
<0.01
No differences were found in diagnoses, functional capacity, smoking and hyperlipidaemia rates, beta-blocker usage and depression scores. Untreated high risk patients were referred for further assessment.

16. Chi-Hang Lee et al. CHEST 2009
Background: We investigated the prevalence and predictors of obstructive sleep apnea (OSA) in patients admitted to the hospital for acute myocardial infarction and whether OSA has any association with microvascular perfusion after primary percutaneous coronary intervention (PCI). Conclusions: We found a high prevalence of previously undiagnosed OSA in patients admitted with acute myocardial infarction. Diabetes mellitus was independently associated with OSA. No evidence indicated that OSA is associated with impaired microvascular perfusion after primary PCI.

17. Occurrence and Predictors of Obstructive Sleep Apnea in a Revascularized Coronary Artery Disease Cohort. Helena Glantz et al. Ann Am Thorac Soc
Results: In total, 662 patients participated in the sleep study. OSA, defined as an apnea–hypopnea index equal to or greater than 15/hour, was found among 422 (63.7%). The prevalence of hypertension was 55.9%; obesity (body mass index > 30 kg/m2), 25.2%; diabetes mellitus, 22.1%; and current smoking, 18.9%. The patients with CAD who did not participate in the study demonstrated an almost similar anthropometric and clinical profile compared with the studied group. The majority (61.8%) of the patients with OSA were non-sleepy (ESS score , 10). Patients with OSA had a higher prevalence of obesity, hypertension, diabetes mellitus, and history of atrial fibrillation, whereas current smoking was more common in the non-OSA group. Age, male sex, body-mass index, and ESS score, but not comorbidities, were independent predictors of OSA.
Conclusions: The occurrence of unrecognized OSA in this revascularized CAD cohort was higher than previously reported. We suggest that OSA should be considered in the secondary prevention protocols in CAD.

20. CR Outcomes PRE POST P-value LOSA: Waist circumference (cm) 93 +/- 10
91 +/- 11 NS
METs (estimated)
7.7 +/- 3
10 +/- 3
<0.001
HOSA:
110 +/- 13
106 +/- 11
0.03
7.2 +/- 3

22. Impact of cardiac rehabilitation on the obstructive sleep apnoea
in the coronary artery disease
David Hupin et al. Annals of Physical and Rehabilitation Medicine 2016.
Objective: Obstructive sleep apnoea (OSA) syndrome is improved by physical activity in the general population. This has not been demonstrated in patients with coronary artery disease (CAD). We aimed to determine a correlation between cardiac rehabilitation and OSA syndrome in CAD patients.
Material/patients and methods: Forty-five CAD patients were included in cardiac rehabilitation programme of Saint-Étienne University Hospital. Patients were classified according to the severity of OSA syndrome.
Results: The reduction in AHI was significant in CAD patients with severe OSA syndrome (8.15 ± 12, P = 0.019). This correlation was even stronger than VO2max and BRS were improved (10.2 ± 8, P < 0.05 with a gain over 20% of VO2max and BRS) at the end of the rehabilitation.
Discussion–conclusion: Severe OSA syndrome is improved by cardiac rehabilitation among CAD patients. Autonomic nervous system regulation by physical activity might be key for alternative therapy for OSA syndrome.

24. Screening -> Assessment via Sleep Study -> Treatment if positive

26. Conclusion:
OSA is an underdiagnosed risk factor in patients attending CR.
CR is an ideal setting for OSA screening and to make referrals for further assessment.