Obstructive Sleep Apnea Diagnosis and Treatment - part 1 pps

Kushida, M.D., Ph.D., RPSGT Director, Stanford Center for Human Sleep ResearchAssociate Professor, Stanford University Medical CenterStanford University Center of Excellence for Sleep Di

Obstructive Sleep Apnea Diagnosis and Treatment

SLEEP DISORDERS

Advisory Board

Antonio Culebras, M.D.

Professor of NeurologyUpstate Medical University

Consultant, The Sleep Center

Community General Hospital

Syracuse, New York, U.S.A

Anna Ivanenko, M.D., Ph.D.

Loyola University Medical Center

Department of Psychiatry and Behavioral Neuroscience

Maywood, Illinois, U.S.A

Clete A Kushida, M.D., Ph.D., RPSGT

Director, Stanford Center for Human Sleep ResearchAssociate Professor, Stanford University Medical CenterStanford University Center of Excellence for Sleep Disorders

Stanford, California, U.S.A

Nathaniel F Watson, M.D.

University of Washington Sleep Disorders Center

Harborview Medical Center

Seattle, Washington, U.S.A

1 Clinician’s Guide to Pediatric Sleep Disorders, edited by

Mark A Richardson and Norman R Friedman

2 Sleep Disorders and Neurologic Diseases, Second Edition,

edited by Antonio Culebras

3 Obstructive Sleep Apnea: Pathophysiology, Comorbidities, and

Consequences, edited by Clete A Kushida

4 Obstructive Sleep Apnea: Diagnosis and Treatment,

edited by Clete A Kushida

Edited by Clete A Kushida

Stanford University Stanford, California, USA

Obstructive Sleep Apnea

Diagnosis and Treatment

Informa Healthcare USA, Inc.

52 Vanderbilt Avenue

New York, NY 10017

© 2007 by Informa Healthcare USA, Inc.

Informa Healthcare is an Informa business

No claim to original U.S Government works

Printed in the United States of America on acid-free paper

10 9 8 7 6 5 4 3 2 1

International Standard Book Number-10: 0-8493-9182-2 (Hardcover)

International Standard Book Number-13: 978-0-8493-9182-8 (Hardcover)

This book contains information obtained from authentic and highly regarded sources Reprinted material is quoted with permission, and sources are indicated A wide variety of references are listed Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequence of their use.

No part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers

For permission to photocopy or use material electronically from this work, please access www copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400 CCC is a not-for-profit organization that provides licenses and registration for a variety of users For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged.

Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and

are used only for identification and explanation without intent to infringe.

Library of Congress Cataloging-in-Publication Data

Obstructive sleep apnea: Diagnosis and treatment / edited

by Clete A Kushida.

p ; cm (Sleep disorders ; 4)

Includes bibliographical references and index.

ISBN-13: 978-0-8493-9182-8 (hb : alk paper)

ISBN-10: 0-8493-9182-2 (hb : alk paper) 1 Sleep apnea syndromes I Kushida,

Clete Anthony, 1960- II Title: Diagnosis and treatment

III Series: Sleep disorders (New York, N.Y.) ; 4

[DNLM: 1 Sleep Apnea, Obstructive diagnosis 2 Sleep Apnea,

Preface

“When in doubt, pressurize the snout.”

—attributal to Philip R Westbrook

I often thought of this mantra during my on-call nights when, as a Stanford sleep medicine fellow, I was awakened from sleep by a technologist informing me that one of the clinic patients had repetitive obstructive apneas with significant oxygen

desaturations The technologist would typically ask, “can I start the patient on CPAP?”

Invariably, I would mutter a drowsy “yes,” often chiding myself that on the previous day I should have clearly written the respiratory thresholds for starting continuous positive airway pressure on the patient’s sleep-study order sheet This anecdote illustrates the fact that continuous positive airway pressure has become such an important and ubiquitous treatment for obstructive sleep apnea since its develop-ment over a quarter century ago The modern sleep specialist has new diagnostic tools and other treatments, such as upper airway surgery and oral appliances, for patients with obstructive sleep apnea; nevertheless, our field is still in its adole-scence with respect to the diagnosis and treatment of obstructive sleep apnea and other sleep disorders

The reader might wonder why a neurologist is editing a two-volume set of books on obstructive sleep apnea, since it is a sleep-related breathing disorder and would therefore appear to be within the domain of pulmonary physicians However, besides pulmonologists—neurologists, psychiatrists, internists, pediatricians, and otolaryngologists have entered the field of sleep medicine Many clinicians now treat patients with sleep disorders on a full-time basis Sleep medicine has truly become multidisciplinary, and a sleep clinician is expected to diagnose and treat a wide range of sleep disorders, from insomnia to restless legs syndrome, that were previously referred by internists to other specialists

It is indeed a testament to the ever-increasing knowledge base on obstructive sleep apnea that there is a need for a two-volume set of books on this topic The first

volume, Obstructive Sleep Apnea: Pathophysiology, Comorbidities, and Consequences

covers the pathophysiology, comorbidities, and consequences of obstructive sleep apnea, with sections exploring the features, factors, and characteristics of this disor-der as well as its associations and consequences This volume focuses on the diag-nosis and treatment of obstructive sleep apnea, and includes a section on special conditions, disorders, and clinical issues The authors and I have tried to conform the conditions and disorders described in this book to the second edition of the

International Classification of Sleep Disorders: Diagnostic & Coding Manual published

by the American Academy of Sleep Medicine in 2006, although some terms, such as obstructive sleep apnea syndrome and sleep-disordered breathing, have been retained in a few statements when appropriate We have also tried to discuss new entities and findings such as complex sleep apnea, oxidative stress, cyclic alternat-ing pattern, and adaptive servo-ventilation However, given the rapidity with which the area of sleep medicine is advancing, it is highly conceivable that two volumes

might not be sufficient to cover the topic of obstructive sleep apnea in just a few short years!

These books could not exist without the excellent contributions of a talented group of international authors; their detailed and comprehensive works are greatly appreciated I am deeply indebted to the renowned and true pioneers of our field of sleep, William Dement, Christian Guilleminault, Sonia Ancoli-Israel, Chris Gillin, and Allan Rechtschaffen, who served as my mentors through various stages of my career In all of my endeavors, I can always count on my parents, Samiko and Hiroshi Kushida, to assist me; these books were no exception I have been very fortunate to serve, along with Dr Dement, as Principal Investigator of the multicenter, rand-omized, double-blind, placebo-controlled Apnea Positive Pressure Long-Term Efficacy Study, sponsored by the National Heart, Lung, and Blood Institute of the National Institutes of Health To date, this is the largest controlled trial funded by the National Institutes of Health in the field of sleep

This book is dedicated not only to my parents but also to the marvelous core team of the Apnea Positive Pressure Long-Term Efficacy Study, consisting of William Dement, Pamela Hyde, Deborah Nichols, Eileen Leary, Tyson Holmes, Dan Bloch,

as well as National Heart, Lung, and Blood Institute officials (Michael Twery and Gail Weinmann), site directors, coordinators, consultants, committee members, key Stanford site personnel (Chia-Yu Cardell, Rhonda Wong, Pete Silva, Jennifer Blair), Data and Safety Monitoring Board members, and other personnel without whom this project could not have functioned in such a meticulous and efficient manner

It is my sincere hope that the reader will strive to become expert in the field of sleep Although there is always room for improvement, awareness of sleep disor-ders by patients, physicians, and the general public is at an all-time high However, available funding for sleep research and the number of young investigators inter-ested in a career in basic or clinical sleep research are areas that need enhancement The interested reader can directly contribute to this field in several ways: applying for membership in the American Academy of Sleep Medicine or Sleep Research Society, serving on committees in these organizations, becoming board certified in sleep medicine, submitting a sleep-related grant proposal to the National Institutes

of Health, and/or just simply learning more about sleep and its disorders

Lastly, etched forever in my memory is a sticker posted on the door of Mary Carskadon’s former office at Stanford that contained words to live by: “Be alert The world needs more lerts.”

Clete A Kushida

1 History and Physical Examination 1

Rory Ramsey, Amit Khanna, and Kingman P Strohl

2 Screening and Case Finding 21

Charles F P George

3 Polysomnography and Cardiorespiratory Monitoring 35

Michael R Littner

4 Upper Airway Imaging 61

Nirav P Patel and Richard J Schwab

5 Alertness and Sleepiness Assessment 89

Max Hirshkowitz

SECTION II: TREATMENT

6 Continuous Positive Airway Pressure 101

Peter R Buchanan and Ronald R Grunstein

7 Bilevel Pressure and Adaptive Servo-Ventilation for Obstructive

and Complex Sleep Apnea 125

Peter C Gay

8 Auto-Positive Airway Pressure 137

Richard B Berry

9 Critical Factors in Positive Pressure Therapy 151

Scott M Leibowitz and Mark S Aloia

10 Noninvasive Positive Ventilation 173

Dominique Robert and Laurent Argaud

11 Upper Airway Surgery in the Adult 191

Donald M Sesso, Nelson B Powell, Robert W Riley, and Jerome E Hester

12 Oral Appliances 217

Peter A Cistulli and M Ali Darendeliler

13 Adjunctive and Alternative Therapies 233

Alan T Mulgrew, Krista Sigurdson, and Najib T Ayas

SECTION III: SPECIAL CONDITIONS, DISORDERS, AND CLINICAL ISSUES

14 Gender Differences in Obstructive Sleep Apnea 247

Vidya Krishnan and Nancy A Collop

15 Obstructive Sleep Apnea in Children 261

Rafael Pelayo and Kasey K Li

16 Obstructive Sleep Apnea in the Elderly 281

Lavinia Fiorentino and Sonia Ancoli-Israel

17 Medication Effects 295

Julie A Dopheide

18 Snoring and Upper Airway Resistance Syndrome 305

Riccardo A Stoohs and Antoine Aschmann

19 Central Sleep Apnea 321

M Safwan Badr

20 Other Respiratory Conditions and Disorders 333

Francesco Fanfulla

21 Other Sleep Disorders 347

Meeta H Bhatt and Sudhansu Chokroverty

Contributors

Maha Alattar Department of Neurology, University of North Carolina, Chapel Hill,

North Carolina, U.S.A

Mark S Aloia Butler Hospital, Providence, Rhode Island, U.S.A.

Sonia Ancoli-Israel Department of Psychiatry, University of California, San Diego

and Veterans Affairs San Diego Healthcare System, San Diego, California, U.S.A

Laurent Argaud Emergency and Intensive Care Department, Edouard Herriot

Hospital, Lyon, France

Antoine Aschmann Medica Surgical Private Clinics, Mülheim, Germany

Najib T Ayas Sleep Disorders Program and Respiratory Division, University of

British Columbia, Vancouver, British Columbia, Canada

M Safwan Badr Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine,

Wayne State University School of Medicine, Detroit, Michigan, U.S.A

Robert D Ballard Advanced Center for Sleep Medicine, Presbyterian/St Luke’s

Medical Center, Denver, Colorado, U.S.A

Richard B Berry Division of Pulmonary, Critical Care, and Sleep Medicine,

University of Florida, Gainesville, Florida, U.S.A

Meeta H Bhatt New York University School of Medicine and New York Sleep

Institute, New York, New York, U.S.A

Daniel B Brown Greenberg Traurig, LLP, Atlanta, Georgia, U.S.A.

Peter R Buchanan Royal Prince Alfred Hospital, Woolcock Institute of Medical

Research and The University of Sydney, Sydney, Australia

Sudhansu Chokroverty Department of Neurology, NJ Neuroscience Institute at JFK

Medical Center, Edison, New Jersey and Seton Hall University, South Orange,

New Jersey, U.S.A

Peter A Cistulli Centre for Sleep Health & Research, Royal North Shore Hospital and

The University of Sydney and Woolcock Institute of Medical Research, Sydney,

Australia

Nancy A Collop Division of Pulmonary/Critical Care Medicine, Johns Hopkins

University, Baltimore, Maryland, U.S.A

M Ali Darendeliler Discipline of Orthodontics, Faculty of Dentistry, The University

of Sydney and Department of Orthodontics, Sydney Dental Hospital, Sydney, Australia

William C Dement Stanford Sleep Research Center, Palo Alto, California, U.S.A.

Julie A Dopheide Schools of Pharmacy and Medicine, University of Southern

California, Los Angeles, California, U.S.A

Francesco Fanfulla Centro di Medicina del Sonno ad indirizzo cardio-respiratorio,

Istituto Scientifico di Montescano IRCCS, Fondazione Salvatore Maugeri, Montescano (Pavia), Italy

Lavinia Fiorentino Department of Psychiatry, University of California, San Diego

and Veterans Affairs San Diego Healthcare System, San Diego, California, U.S.A

Peter C Gay Pulmonary, Critical Care, and Sleep Medicine, Mayo Clinic College

of Medicine, Rochester, Minnesota, U.S.A

Charles F P George University of Western Ontario, London Health Sciences

Centre, London, Ontario, Canada

Ronald R Grunstein Royal Prince Alfred Hospital, Woolcock Institute of Medical

Research and The University of Sydney, Sydney, Australia

Jerome E Hester Department of Otolaryngology/Head and Neck Surgery,

Stanford University Medical Center, Palo Alto, California, U.S.A

Max Hirshkowitz Sleep Center, VA Medical Center and Departments of Medicine

and Psychiatry, Baylor College of Medicine, Houston, Texas, U.S.A

Amit Khanna Department of Family Medicine, Case Western Reserve University,

Cleveland, Ohio, U.S.A

Vidya Krishnan Division of Pulmonary/Critical Care Medicine, Johns Hopkins

University, Baltimore, Maryland, U.S.A

Scott M Leibowitz The Sleep Disorders Center of Cardiac Disease Specialists,

Atlanta, Georgia, U.S.A

Kasey K Li Sleep Apnea Surgery Center, East Palo Alto, California, U.S.A.

Michael R Littner VA Greater Los Angeles Healthcare System, Sulpulveda,

California and David Geffen School of Medicine, University of California, Los Angeles, California, U.S.A

Alan T Mulgrew Sleep Disorders Program and Respiratory Division, University of

British Columbia, Vancouver, British Columbia, Canada

Nirav P Patel Division of Pulmonary, Critical Care, and Allergy, Center for

Sleep & Respiratory Neurobiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania, U.S.A

Rafael Pelayo Stanford University Center of Excellence for Sleep Disorders,

Stanford, California, U.S.A

Nelson B Powell Department of Otolaryngology/Head and Neck Surgery,

Stanford University Medical Center and Division of Sleep Medicine, Department of Behavioral Sciences, Stanford School of Medicine, Palo Alto, California, U.S.A

Rory Ramsey Division of Pulmonary and Critical Care Medicine, Department of

Medicine, Case Western Reserve University, Cleveland, Ohio, U.S.A

Robert W Riley Department of Otolaryngology/Head and Neck Surgery, Stanford

University Medical Center and Division of Sleep Medicine, Department of Behavioral Sciences, Stanford School of Medicine, Palo Alto, California, U.S.A

Dominique Robert University Claude Bernard and Edouard Herriot Hospital,

Lyon, France

Richard J Schwab Division of Sleep Medicine, Pulmonary, Allergy, and Critical Care

Division; University of Pennsylvania Medical Center, Philadelphia, Pennsylvania, U.S.A

Donald M Sesso Department of Otolaryngology/Head and Neck Surgery,

Stanford University Medical Center, Palo Alto, California, U.S.A

Krista Sigurdson Sleep Disorders Program and Respiratory Division, University of

British Columbia, Vancouver, British Columbia, Canada

Riccardo A Stoohs Somnolab Sleep Disorders Centers—Dortmund, Essen,

Dortmund, Germany

Kingman P Strohl Division of Pulmonary and Critical Care Medicine, Department

of Medicine, Case Western Reserve University, Cleveland, Ohio, U.S.A

Bradley V Vaughn Department of Neurology, University of North Carolina, Chapel

Hill, North Carolina, U.S.A

History and Physical Examination

Rory Ramsey

Division of Pulmonary and Critical Care Medicine, Department of Medicine,

Case Western Reserve University, Cleveland, Ohio, U.S.A.

Amit Khanna

Department of Family Medicine, Case Western Reserve University, Cleveland,

Ohio, U.S.A.

Kingman P Strohl

Division of Pulmonary and Critical Care Medicine, Department of Medicine,

Case Western Reserve University, Cleveland, Ohio, U.S.A.

INTRODUCTION

The patient-physician encounter is an inquiry designed to disclose and test disease hypotheses Physicians detect “cues” early in a patient interview and use them to generate predictions about a disease presence or state They then ask questions to test the likelihood of hypothesized disease(s) and answers modify perceived proba-bility This process continues until a reasonable list of potential problems, a differential diagnosis, is shaped and decisions become more explicit Physicians rely on their own experience, skill, and knowledge base to assign values to the presence or absence of key clinical features

The purpose of this chapter is to identify those features in sleep history taking that are more likely to assign diagnostic value The chapter will start by outlining some of the cues that physicians use to direct a general sleep history and then detail the contribution of other elements important in the consideration of obstructive sleep apnea (OSA) A sleep-specific physical examination will then be discussed Adult and pediatric issues will be compared

It is important to recognize that there are major limitations in the current literature To a considerable extent, the recommendations in this chapter result from data from uncontrolled studies, case series, consensus guidelines, practice para-meters, and other less rigorous forms of evidence like expert opinion; most of this literature is not focused on how a history and physical help in patient management

or outcome There is an enormous heterogeneity in study design, quality and in populations studied, so that a concordance among studies on the history and physi-cal is difficult to discuss at more than a superficial level Finally, clinical studies express associations in terms that are not always interchangeable, for example,

relative risk (RR), odds ratio (OR), correlation coefficient (r), positive predictive

value, likelihood ratio (LR), sensitivity, specificity, and so on These features led to challenges in producing this review

Yet, there is value still present in a general medical examination No features

or combination of features are ever fully sensitive and specific for sleep apnea or for sleep problems A physician–patient encounter should do more than just capture a single suspected diagnosis The process may involve not only a sleep outcome, but

1

Section I: Diagnosis

2 Ramsey et al.

can disclose comorbid conditions and personal issues that could optimize testing and treatment

MAIN CUES

Excessive Daytime Sleepiness

Excessive daytime sleepiness (EDS) is very common Epidemiological studies estimate the prevalence to be 8% to 30% in the general population (1–3) depending

on the definition of sleepiness and the population sampled A primary care based study found that 38.8% experienced wake time tiredness or fatigue at least three to four times per week (4) and a study of sleep clinic patients found 50% complaining of excess sleepiness (5)

clinic-EDS is a challenging symptom because of a significant overlap with features

of fatigue and the difficulty patients and physicians have in differentiating between the two symptoms Sleepiness is the tendency to fall asleep, whereas fatigue involves

a task context with musculoskeletal and/or neurasthenic qualities For instance, one author has described fatigue as a drive for rest, and daytime sleepiness as a drive for sleep (6) Sleepiness may occur more often during “passive” conditions, such as watching television or sitting as a passenger in a car; but in its most severe form, sleepiness can intrude into “active” conditions, such as talking to someone or driving a car

Several instruments have been developed to identify and measure symptoms

of EDS (7) Currently, the most useful instrument may be the Epworth sleepiness scale (8) It is a list of eight questions that measure the propensity to sleep in familiar situations and has good test–retest reliability (9)

EDS is not particularly useful in directing one towards the consideration of any one disease It is, however, very important in the quantification of the problem

of sleepiness and should be described in regard to onset, situation, and chronicity Specifics about functional sleepiness are probably the most useful It is also important

to note that people often underestimate their sleepiness (10) While the differential diagnosis of EDS is wide, sleep-related disorders should be considered early on

Snoring (See Also Chapter 18)

Community-based studies have estimated that as many 30% to 40% of the general population (2,3,11) snores and others have shown that more than 50% of primary care populations snore (4) Studies from community, primary care, and sleep clinics have all shown a significant relationship between the presence of snoring and sleep apnea (2,4,12–15), and some have incorporated snoring into clinical prediction rules for sleep apnea (4,12–14) While snoring is clearly helpful in suggesting sleep apnea as

a diagnostic possibility, its high prevalence in widespread populations impairs its ability to identify real disease Nevertheless, this symptom should be described in regard to onset, severity, frequency, quality, and chronicity

Witnessed Apneas/Bed Partner’s Reports of Choking or Gasping

Polls have estimated that the prevalence of witnessed apneas in the general adult population ranges from 3.8% to 6% (2,11,16) A primary care population survey found that 11.1% of responders had observed breathing pauses at least one to two times per month (4) Community-, primary care-, and sleep clinic-based studies have all demonstrated a strong relationship between sleep apnea and witnessed apneas or nocturnal choking and several have incorporated these reports into multivariate prediction models for sleep apnea (12,14,17) One community-based

History and Physical Examination 3

study found that the report of apnea increased the odds of sleep apnea nine-fold (2) and another sleep clinic-based study found that it increased the odds 19-fold (18) In the Sleep Heart Health Study, witnessed apneas had the highest prevalence of all collected demographic and predictor variables in patients with an apnea–hypopnea index (AHI) ≥ 15 (15) However, the utility of this report is limited by a low sensitivity

as only 9% of these sleep apnea subjects reported this symptom (15) Two additional limitations include the fact that not everyone has a bed partner and people may be poor reporters when it comes to describing respiratory events at night (19)

Insomnia

Insomnia is a repeated difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate time and opportunity for sleep and results in some form of daytime impairment (20) Collectively, insomnia encompasses: adequate sleep opportunity, a persistent sleep difficulty, and associated daytime dysfunction Among adults, insomnia typically manifests as difficulty initiating sleep, maintaining sleep, waking up too early, or sleep that is chronically nonrestorative or poor in quality When considering adults who experience daytime sleepiness a few days a week versus those who do not, 73% complain of at least one symptom of insomnia, while only 25% carry a diagnosis of a sleep disorder (21) Detailed inquiry regarding the use of sleep aids is important when assessing patients for insomnia

Sleep-Wake Schedule

Asking the patient for his/her Sleep-Wake schedule is important in demarcating a sleep complaint Schedule abnormalities in wake and sleep times are clues to the more common sleep disorders (i.e., insomnia and circadian rhythm disorders) and can also be useful in suggesting the presence of other sleep disorders (i.e., narcolepsy and sleep apnea) It can be important to elicit prebedtime rituals, such as caffein-ated/acidic foods, prescription/illicit/over-the-counter (OTC)/herbal pharmaceu-ticals, tobacco, and presleep physical, emotional, or cognitive stimulations Nocturnal waking behaviors, especially nocturia, are proposed as a clue for sleep apnea (22)

An inquiry would include details on usual bedtime, time to falling asleep (sleep latency), awakenings from sleep (frequency, length, identifiable causes), final wake-up time (naturally; prompted by alarm, pet, or another person), and nap times and nap length A formal sleep log over several days to weeks can be useful, since there can often be a discrepancy between remembrance reports on the first visit and prospectively recorded events

4 Ramsey et al.

Cataplexy

Cataplexy is specifically used in the diagnosis of narcolepsy Cataplexy refers to a sudden loss of postural tone that is precipitated by the experience of strong emotion Triggers include joy, sadness, anger, and hilarity Laughter is the most common trigger (23,24) Cataplexy can manifest in many ways including head nodding, collapsing, dropping an item, and so on The knees, face, and/or neck are the most common muscle groups involved; oculomotor involvement can also occur, affecting one’s vision Respiratory muscles are not affected by cataplexy Loss of conscious-ness is rare (23) Cataplectic events are usually short, ranging from a few seconds to

at most several minutes, and recovery is immediate and complete (23) People found

to have narcolepsy, however, often carry a variety of other diagnoses such as odic paralysis, absence seizures, and fugue states, often because the trigger events are not elicited or ignored Other associated features of narcolepsy include sleep paral-ysis, hypnagogic hallucinations, and reports of poorly consolidated sleep (described below) These symptoms can however occur, albeit infrequently, in normal patients and isolated symptoms may be present in those with other sleep disorders

peri-A curious correlation is reported with one’s month of birth and increased odds

of manifesting narcolepsy Retrospectively, when 800 birthdates were reviewed from confirmed narcoleptics with cataplexy in North America and Europe, the monthly distribution of birth yielded a peak in March with a maximal OR at 1.45 and a trough in September with a minimal OR at 0.63 (24,25)

Sleep Paralysis

Sleep paralysis is a transient, generalized inability to move or to speak during the transition between sleep and wakefulness Such experiences can be frightening to the patient, as muscle control is regained within a few minutes The sensation of being unable to breathe is sometimes perceived Sleep paralysis is reported in 40% to 80% of narcoleptics, and may occur with sleep deprivation and can be familial (20)

Hypnagogic Hallucinations

Hypnagogic hallucinations are vivid perceptual (visual, tactile, auditory) ences typically occurring at sleep onset These experiences are often accompanied

experi-by feelings of fear Recurring themes include being caught in a fire, being attacked,

or flying through the air Recurrent hypnagogic hallucinations are experienced by 40% to 80% of patients with narcolepsy and cataplexy (20)

Movements During Sleep

This class of symptoms can encompass a number of disparate but important entities including restless leg syndrome (RLS), periodic limb movement disorder (PLMD), and parasomnias RLS is characterized by an irresistible urge to move the legs and

is usually accompanied by uncomfortable and unpleasant sensations in the legs (dysesthesias) Spontaneous unpleasant sensations (e.g., “creepy-crawly,” “ants marching up my legs”) of the limbs occur at rest and are usually relieved by move-ment This typical description is extremely suggestive if not diagnostic RLS is estimated to occur in approximately 2.5% to 15% of the population, with a female predominance, occurring 1.5 to 2 times more commonly in women, and its preva-lence increases with age (26–29) Other considerations include conditions such as

History and Physical Examination 5

muscle cramps and myotonic jerks, positional discomfort, hypotensive akathisias, sleep starts (hypnic jerks), neuroleptic-induced akathisias, sleep-related leg cramps, pain associated with arthritis, vascular conditions, injuries, and neuropathy can all mimic RLS to a certain degree

A majority of patients with RLS also have concomitant periodic limb ments during sleep (PLMS) These PLMS primarily manifest by kicking or jerking leg movements at night, but they can also affect the arms PLMS can be mistaken as leg kicks that occur around the time of arousal following an apnea or more rarely as

move-a seizure The individumove-al leg movements thmove-at comprise PLMS need to meet specific polysomnographic criteria (i.e., 25% of baseline amplitude, 0.5–5 seconds duration, separated by 4–90 seconds, train of four individual leg movements equals one periodic leg movement) as well as resulting in a clinical sleep disturbance or day-time fatigue in order to meet the criteria for PLMD (20)

For the most part, parasomnias involve complex, seemingly purposeful, and goal-directed behaviors There are 12 core categories of parasomnias, with only rapid eye movement (REM) sleep behavior disorder (RBD) requiring polysomno-graphic confirmation for diagnosis (20) Although the remaining 11 categories are clinical diagnoses, coexisting polysomnographic collaboration findings can be very helpful adjuncts at confirming or excluding certain diagnoses OSA-induced arousals from REM or non-REM (NREM) sleep with complex or violent behaviors may trigger parasomnias, including: RBD, confusional arousals, sleepwalking, and sleep terrors, and sleep-related eating disorder The differential diagnosis would include nocturnal complex seizures or nocturnal dissociative states It is suggested that rebound slow-wave sleep with initiation of therapy for sleep apnea could trigger parasomnia phenomena

SPECIFIC CUES FOR SLEEP APNEA WITH AN EMPHASIS

ON ADULT PRESENTATIONS

Demographics

Sleep apnea is a very prevalent disorder in important populations Epidemiological studies estimate the prevalence to be 2% to 4% in the general population (3,30,31), while other, more selected population studies achieved a prevalence range of 7% to 16% (2,32) Prevalence estimates (and therefore pretest probability) increase in clinical populations due to an enrichment of medical problems Rates encountered

in the primary care or hospital settings are particularly high: primary care (high risk 37.5%) (4), obese 40% to 60% (33), bariatric surgery evaluation 71% to 87% (34,35), hypertension 38% (36), stable outpatient congestive heart failure (CHF) > 50% (37,38), coronary artery disease (CAD) > 50% (39), acute stroke > 70% (40,41), and sleep clinic 67% (29)

In regards to the presentation of sleep apnea, studies show a strong ship between age and sleep apnea (see also Chapter 16) (15,30,42,43) Duran (2) found that sleep apnea prevalence increased with age with an OR of 2.2 for each 10-year increase The Sleep Heart Health Study noted that prevalence rose steadily with age

relation-up to 60 years at which point a plateau in prevalence occurs around 20% (15) It has also been shown that the severity of sleep apnea (42) and the effect of body mass index (BMI) seem to decrease with age (15,43) and that the magnitude of associations for sleep apnea, snoring, and breathing pauses also decreases with age (15)

Men have a higher prevalence of sleep apnea than women across all ages in epidemiological (3,31,44) and clinic-based studies (see also Chapter 14) This effect

6 Ramsey et al.

diminishes with time, however, and both sexes achieve a similar incidence by age 50 (43) A study of OSA incidence and its risk factors found the risk for sleep apnea in men increased only marginally with age, while it increased very significantly in women: the OR (confidence interval) for increased AHI per 10-year increase was 2.41

in women (1.78–3.26) and only 1.15 (0.78–1.68) in men (43) A study of Hong Kong women found a 12-fold rise in the prevalence of sleep apnea in women between the fourth and sixth decades (31) There is a large amount of literature to support the role of menopause in modulating this increased risk for sleep apnea in women around the age of 50 (44–46) In general, men and women are present with the same constellation of sleep-related symptoms and complications (47) Women with OSA may be slightly older, more obese, more likely to use sedatives, and complain of insomnia and depression (48)

It is not clear if race can be categorically used to confer risk, or if race difference

is just a surrogate for a different risk profile A study of sleep apnea risk factors in the Sleep Heart Health Study did not show a significantly higher prevalence in African-Americans (15) and another did not note any differences in respiratory disturbance index (RDI) when adjusted for known confounders (49) In contrast,

a study of older community dwelling adults found that African-Americans had a 2.5 times greater odds of having an AHI > 30 (50), and the Cleveland Family Study found the prevalence of sleep apnea in young African-Americans was higher than that of Caucasians (51)

Studies in Asia estimate the prevalence of sleep apnea to be similar to that of the West (30,31) This is an intriguing finding given that obesity, the risk factor believed to modulate a large part of the risk for sleep apnea in the West, is less common in Asia Other factors must therefore act in the expression of this disorder Craniofacial morphology has been implicated as a modifier of risk in nonobese populations but could also interact with obesity as well (52–54)

History of Present Illness

General issues in the presentation would be the age of onset of symptoms as well as some consideration of the trajectory of illness severity Some of these features are listed in Table 1, and includes features important in both adult and pediatric popu-lations The pediatric examination is also discussed in a separate section below.Sleepiness is very common in sleep apnea patients: 38% to 51% in one epide-miological study (55) and 47% to 73% in a sleep clinic population (56) Despite this

it is not associated with sleep apnea in clinical studies This is in large part due to difficulty in differentiating sleep from fatigue In a study of sleep apnea patients’ perception of their problems, lack of energy, tiredness, and fatigue were more prev-alent complaints than sleepiness (56)

Snoring is extremely common in sleep apnea patients and its absence should make OSA less likely (13) In one study only 6% of patients with OSA did not report snoring Keep in mind however, that many patients have misperceptions about their snoring and tend to underestimate it (57) Some studies have shown that a report of

“loud” habitual snoring strengthens by seven-fold the statistical association with sleep apnea and snoring (4,15,58) Witnessed apneas are relatively specific for sleep apnea, but have a low sensitivity (15)

Insomnia complaints are highly prevalent in OSA Fifty-five percent of patients being referred for possible evaluation of OSA were noted to have complaints of insomnia, with difficulties maintaining sleep (38.8%) being more common than

History and Physical Examination 7

difficulties initiating sleep (33.4%) or early morning awakenings (31.4%) Despite the overall high prevalence of insomnia complaints in this study population, insomnia was more common in patients without rather than with significant sleep-disordered breathing (81.5% with AHI < 10 vs 51.7% with AHI > 10) (59) The high prevalence of insomnia complaints may be attributable to the fact that the sleep disruption associ-ated with OSA may be perceived as insomnia, or perhaps such patients with insomnia and OSA are more symptomatic, thus more likely to seek medical attention

Weight gain increases the probability of sleep apnea One large based study found a 10% weight gain and predicted a 32% increase in AHI This translated to a six-fold increase in the odds of developing (moderate-to-severe) sleep apnea (32) Inversely, a decrease in weight leads to an improvement in sleep apnea Studies in bariatric surgery patients show a dramatic improvement in RDI after weight loss (35,60)

population-Frequent awakening from sleep to urinate is common in sleep apnea patients One retrospective study found a prevalence of 49% in sleep apnea patients (61) and others have noted frequent nocturia is related to sleep apnea severity (61–63).Nocturnal angina may be related to apneas in some patients with ischemic heart disease and sleep-disordered breathing Small series in patients with ischemic heart disease and relatively severe sleep apnea suggested a link between myocardial ischemia and apneas (64,65) However, these findings conflict with a larger study that included patients with less severe sleep apnea and failed to appreciate a signifi-cant association (66)

Past Medical History

OSA will coexist with other sleep disorders A retrospective analysis of 643 OSA patients found that 31% had another sleep disorder: 14.5% had poor sleep hygiene and 8.1% had PLMD (67) In two other studies more than 50% of sleep apnea patients complained of insomnia (59,68)

Sleep apnea is not only associated with cardiovascular disease but may directly contribute to its pathogenesis It was present in 38% of hypertensive subjects in one

TABLE 1 Features of Emphasis in the Adult and Pediatric Examination

Impact on daytime

functioning

Irritability, mood swings, hyperactivity, automatic behaviors, work

or academic performance, behavior of concern (inappropriate napping, inattentiveness), absences from work or school Sleep/wake schedules Usual bedtime, fall asleep time, wake time, napping habits,

weekday/weekend variations Customs surrounding sleep Presleep routines and related transitional objects (television,

pacifier, toy, etc.) Sleep environment Shared or private room, bed partners (including pets/toys/stuffed

animals); electronics or other toys that may impede sleep routines; persistence or resolution of sleep complaints in other environments (hotels, sleepovers, etc.)

Body position(s) during sleep Side sleeping and/or neck hyperextension to relieve obstruction Exposures Caffeinated beverages, tobacco products, recreational drugs Other sleep behaviors Snoring, witnessed apneas, paradoxical breathing, mouth

breathing with dry mouth and throat, morning headaches, gastroesophageal reflux, sweating (may suggest increased work of breathing), stereotypic movements/complaints suggestive of seizure or movement disorders (including parasomnias and restless legs syndrome)

8 Ramsey et al.

study (36) A dose–response relationship is present (69) and several trials found a small but significant improvement in hypertension with sleep apnea treatment (70–72) Others suggest that the prevalence of sleep apnea in patients with CAD, postmyo-cardial infarction, CHF, and poststroke to be > 50% (37–41) Results from the Sleep Heart Health Study show increasing odds of self-reported heart failure, stroke, and CAD in subjects with a high AHI (73) Additionally, a pathogenic role is suggested

by observational studies that show fewer adverse cardiovascular outcomes in treated versus untreated patients (74–76)

Several studies have found that sleep apnea is independently associated with glucose intolerance and insulin resistance (33,77) The Sleep Heart Health Study found that patients with mild and moderate/severe OSA had increased adjusted ORs for fasting glucose intolerance: 1.27 (0.98, 1.64) and 1.46 (1.09, 1.97), respec-tively (77) At least one treatment study has found improvement in glucose control

in patients treated for sleep apnea (78)

Depression is linked to sleep apnea in a number of correlation studies Most are small, use different instruments to measure depression, and indicate that 24% to 58% of sleep apnea patients have some measure of depression (79,80) In a larger European telephonic survey, 17.6% with a Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) breathing-related sleep disorder also had a diagnosis of

a major depressive disorder (81)

Sleep apnea in the setting of pulmonary diseases is called the “overlap syndrome.” Chronic obstructive pulmonary disease is the most common of these, but has a prevalence in the sleep apnea population similar to that of the general population (82) Pulmonary arterial hypertension is another disease but is much less common and the prevalence of sleep apnea in these patients is not well studied (83).Hypothyroidism symptoms of fatigue can overlap with those of sleep apnea Case series have reported improvement or resolution of sleep apnea in selected patients treated with thyroxine alone (84) Nonetheless, the limited evidence available suggests the prevalence of hypothyroidism in sleep apnea patients is no different than that seen in the general population (85) and routine screening in the absence of other signs of hypothyroidism is not cost-effective Cases have also described lingual thyroids causing airways obstruction at night (86)

Glaucoma (87), end-stage renal disease (88,89), and gastroesophageal reflux disease (90,91) have been reported to occur with OSA, but the specificity of the asso-ciations are not established

The occurrence of sleep disturbances during pregnancy is well documented, but the prevalence and incidence of specific sleep disorders is not confirmed in large-scale population studies A spectrum of association between pregnancy and sleep disturbances ranges from an increased incidence of excessive sleepiness, insom-nia, nocturnal awakenings, and parasomnias (especially restless legs syndrome) to snoring, and both obstructive and central sleep apnea (92) Although specific sleep disorders tend to emerge during different stages of pregnancy, the third trimester appears to be the most vulnerable Of special attention are those women who gain excessive weight during pregnancy Thus, during routine perinatal obstetrical care, the sleep history should be periodically revisited

Social History

Sleep apnea significantly worsens after heavy alcohol ingestion (93,94) The effect of more moderate levels of alcohol ingestion on sleep apnea are not as clear and results