Fall 2014 Meeting October 3-4, 2014

Hypoglossal Nerve Stimulation as a Treatment for Sleep Apnea Mark G. Goetting, MD Bronson Sleep Health Kalamazoo, MI

Objectives • Present the need for further alternatives to CPAP. • Discuss the theoretical basis of HNS. • Present the early clinical trials. • Speculate on how HNS may be integrated into sleep medicine practice.

Conflict of Interest Disclosures for Speakers

Type of Potential Conflict

Details of Potential Conflict

Grant/Research Support

Inspire Medical

Consultant Speakers’ Bureaus Financial support

Other

Teva Pharmaceuticals

Long Term Adherence to CPAP • 40-70% • 4 hours/night on 70% of nights • Time threshold 2.8 hours/night average

Alternatives to CPAP • • • • •

Dental devices Body modeling Positional therapy Oral pressure therapy Various surgical therapies

Base of Tongue is Often the Source of the Problem Neuro-stimulation well suited for base of tongue obstruction

Base of Tongue Obstruction

Therapy Mechanism Understood • Decline in neuromuscular activity at base of tongue during sleep • Hypoglossal nerve modulates neuromuscular function at the base of tongue • Mild stimulation of the hypoglossal nerve activates select upper airway muscles and can prevent base of tongue obstruction

Potential Advantages of HNS • Works with patient’s physiology • No removing or altering anatomy • Greater adherence • Patients control therapy stop and start times • Reversible

8

Internal Components

9

External Programmers

10

Timing of Stimulation Deliver mild stimulation at “optimal time” in patient’s breathing cycle

inspiration stimulation

Sensor Waveform

Stimulation

History of HNS 1994

Project Initiated

2011 Feasibility Study #1 (8 patients)

2nd Gen Technology Development

Inspire Medical Systems Formed

Feasibility Study #2 (30 patients)

STAR Trial Begins (120 patients

Eight patients implanted – (3) Antwerp, Belgium – (3) Johns Hopkins University – (1) Marburg, Germany – (1) Göteborg, Sweden

AHI

Total System Implant Status during initial Feasibility Trial 90 80 70 60 50 40 30 20 10 0

pre Therapy efficacy – 7/8 patients experienced reductions in AHI to below 20

–

Reduction in AHI from a mean of 53 to 13

antw1 balt1 antw2 antw3 got1 balt2 marb1 balt3 post

Without Stimulation

With Stimulation

Untreated OSA Results in Major Economic Cost

The Price of Fatigue, Harvard Medical School, Division of Sleep Medicine, 2010 healthysleep.med.harvard.edu/file/20

24

What is a QUALY? •

•

• •

A quality-adjusted life-year (QALY) takes into account both the quantity and quality of life generated by healthcare interventions. It is the arithmetic product of life expectancy and measure of the quality of the remaining life-years. A QALY places a weight on time in different health states. A year of perfect health is worth 1 and a year of less than perfect health is worth less than 1. Death is considered to be equivalent to 0; however, some health states may be considered worse than death and have negative scores.

What is cost effectiveness? •

•

Cost-effectiveness analysis compares the costs and health effects of an intervention to assess the extent to which it can be regarded as providing value for money. This informs decisionmakers who have to determine where to allocate limited healthcare resources

In cost–utility analysis the benefits are expressed as qualityadjusted life-years (QALYs) and in cost–benefit analysis in monetary terms.

Costs of intervention CER = Health effects produced (e.g. life-years gained)

ICER =

Differences in costs between Programs P1 and P2 Differences in health effects between Programs P1 and P2

Overview of Markov Model

WING TECH INC.

Endpoints: M HTN

UAS Treatment

• Quality of Life

Health states M Stroke • Costs

Defined population (Moderateto-severe OSA)

M MI

• Life years

M Death

Identical Health No treatment states

• Events: – Myocardial

infarction

– Stroke – Motor vehicle crashes (fatal and non-fatal) – Death For UAS And No treatment

M

Markov model components

UAS Costs • Total implantation & peri-procedural cost $29,609 • Total annual routine F/U cost $177 • Battery replacement cost* $ 16,925

* Assumed to be every 11 years Pietzsch et al Unpublished data

Health outcomes and incremental cost-effectiveness Risk of MI

Risk of Stroke

Expected Cost ($), Effectiveness number of discounted (QALY), MVC discounted 1.030 243,543 9.54

Lifetime No Treatment

0.481

0.249

UAS Treatment

0.389

0.240

0.367

286,497

10.63

Absolute Difference Relative Risk

0.092

0.009

0.663

42,953

1.09

0.81

0.96

0.36

No Treatment

0.136

0.067

0.473

90,487

5.44

UAS Treatment

0.086

0.050

0.160

115,218

5.87

Absolute Difference Relative Risk

0.050

0.017

0.313

24,731

0.43

0.63

0.75

0.34

ICER ($/QALY), discounted 39,471

10-years

57,773

Pietzsch et al Unpublished data

Cost-Effectiveness and Use of Selected Interventions in the Medicare Population

NEJM 2005 353:1516-22

CPAP: Health Outcomes and Incremental Cost Effectiveness

SLEEP 2011 34: 695-709

Cost Effectiveness Comparison ICER ($/QALY) $15,915

CPAP for OSA

$39,471

UAS for OSA

$42,605

CRT-D for heart failure

$45,033

Insulin and CGM for Type 1 diabetes $CGM, continuous glucose monitoring

$50,000

$100,000

SLEEP 2011 34:695-709

Patient perspective – how fast can I recover, and what will my results be?

Therapy Efficacy

Patient acceptability threshold Upper Airway Stim Next day

MMA Surgery 30 day recovery ~1000 cases Multi-level Surgery 5-7 day recovery ~35,000 cases Post-Op Pain & Recovery Time

• •

Recovery time may be a factor for OSA surgery patients, who are working age The gap between the number of cases for multi-level surgery vs. MMA surgery suggests patients are less willing to invest the time/recovery needed for MMA surgery, despite it’s efficacy

Sleep Surgery Outcome Measures

SLEEP 2010;33(10):1396-1407.

Conclusions • Relative to the acknowledged willingness-topay threshold of $50,000–$100,000/QALY, UAS is a cost-effective therapy in the U.S. healthcare system • Accounting for patient preference and the current evidence, UAS appears to be preferable to MMA and possibly other surgical approaches

Fall 2014 Meeting October 3-4, 2014

Hypoglossal Nerve Stimulation as a Treatment for Sleep Apnea Mark G. Goetting, MD Bronson Sleep Health Kalamazoo, MI