Chronic Insomnia Disorder in Australia

A REPORT TO THE SLEEP HEALTH FOUNDATION

1,2 1. Appleton Institute, CQUniversity Australia 44 Greenhill Amy C Reynolds Road, Wayville SA 5034 3,4 Sarah L Appleton 2. School of Health, Medical and Applied Sciences, CQUniversity Australia 4,5 Tiffany K Gill 3. Adelaide Institute for Sleep Health: A Flinders Centre of Robert J Adams 3,4 Research Excellence, Flinders University, Bedford Park, SA. 4. The Health Observatory, Adelaide Medical School, The University of Adelaide, SA.

5. South Australian Health and Medical Research Institute, Adelaide, Australia Chronic Insomnia Disorder in Australia A Report to the Sleep Health Foundation

Amy C Reynolds1,2, Sarah L Appleton3,4, Tiffany K Gill4,5 & Robert J Adams3,4

1. Appleton Institute, CQUniversity Australia 44 Greenhill Road, Wayville SA 5034

2. School of Health, Medical and Applied Sciences, CQUniversity Australia

3. Adelaide Institute for Sleep Health: A Flinders Centre of Research Excellence, Flinders University, Bedford Park, SA.

4. The Health Observatory, Adelaide Medical School, The University of Adelaide, SA.

5. South Australian Health and Medical Research Institute, Adelaide, Australia

This work was supported by the Sleep Health Foundation, an Australian not‑for‑profit organisation devoted to improving sleep health, and an unrestricted grant from Merck Sharp & Dohme (Australia) Pty Limited which had no part in conception, planning, execution or write‑up of it.

Publication and graphic design by Flux Visual Communication www.designbyflux.com.au

July 2019

2 Chronic Insomnia Disorder in Australia EXECUTIVE SUMMARY Sleep problems are common and costly to the Australian community. One common sleep condition is insomnia.

Chronic insomnia disorder is broadly were responsible for the survey defined as a perceived difficulty design and analysis. The survey with sleep initiation, consolidation, was conducted online; methodology duration, or quality despite adequate was approved by the University opportunity to sleep, plus subsequent of Adelaide Office of Research daytime impairment, that occur at Ethics, Compliance and Integrity’s least three times per week, lasting Human Research Ethics Secretariat at least three months. The daytime (H‑2018‑214). consequences encompass a wide variety of issues, including significant Sleep problems remain prevalent distress or impairment in social, across the community, irrespective occupational, educational, academic, of age and gender. Around 60% of behavioural or other important areas people report at least one sleep of functioning. symptom occurring 3 or more time per week, and this is consistent The prevalence of chronic insomnia across age groups. However, the disorder is presently unclear, type of symptom varies with age. as there are limited studies that Older people are more likely to have have examined the prevalence difficulty maintaining sleep, while and correlates of insomnia using younger adults have trouble initially definitions which correspond to getting off to sleep. Self-reported the contemporary classifications of daytime impairments related to sleep the International Classification of are more common among female Sleep Disorders (ICSD‑3) and/or the respondents and younger adults. Diagnostic and Statistical Manual of Mental Disorders (DSM‑V). The Most people who fulfill diagnostic primary aim of this study was to criteria for chronic insomnia do not determine the prevalence of insomnia report a prior diagnosis of insomnia. disorder in the Australian population Overall, insomnia according to according to established current current diagnostic criteria is more diagnostic criteria, and examine common in older Australians. This socio‑demographic and other occurs despite no apparent change in correlates of insomnia in Australia. prevalence in overall sleep symptoms across age, and a decline in daytime The survey was conducted between symptoms with age, in the population March and April 2019 on behalf more broadly. The main influence on of the Sleep Health Foundation this is that older adults are far more among 2,044 adults aged 18 likely to report adequate opportunity years and over across Australia, to sleep than younger adults. This with representativeness for age, indicates that much of the sleep sex, location and an indicator of problem among younger adults can socio‑economic status. Researchers be attributed to circumscribed sleep from Flinders University, The opportunities from external social University of Adelaide and the pressures and behaviour patterns. Appleton Institute of CQUniversity

A Report to the Sleep Health Foundation 3 Prevalence of insomnia by different definitions

400

14.8% (303) 300 12.2% (250)

200 7.5% (153)

100 NUMBER OF PEOPLE NUMBER OF

0 Self-reported insomnia DSM-V ICSD-3 (previous doctor diagnosis) Insomnia Insomnia

In addition, daytime sleepiness as Insomnia is associated with Relatively few Australians speak the only daytime impairment is far lower income, financial stress, to healthcare professionals about more common among older adults. unemployment, and retirement in the sleep, despite almost half of the This suggests the insomnia phenotype Australian population. In addition, with population reporting inadequate differs across age groups, with the the ICSD‑3 criteria, which are inclusive sleep. Furthermore, sleep is often “hyperarousal” phenotype much less of people in whom pain affects sleep, only discussed as a secondary issue common in the elderly. insomnia prevalence is higher in those during a consultation for other unable to work due to disability. reasons. Use of any form of treatment Similarly, female respondents for insomnia is uncommon, even are much less likely than male The prevalence of insomnia is among those who report daytime respondents to report adequate relatively unaffected by activities in impairments or who have discussed opportunity to sleep (43% versus 60%), the hour before bed, with similar rates sleep problems with a health particularly in the 25 to 44 year age in those who routinely use technology, professional. Usage rates identified group. This contributes to the lower work, eat, drink alcohol or are on in this survey indicate a need for prevalence of chronic insomnia in social media frequently compared to greater education or awareness and female respondents. those who do not. expanded access, to promote use of the gold standard treatment in One of the primary differences Single item questions about diagnosed insomnia, i.e. cognitive behavioural between DSM‑V and ICSD‑3 chronic insomnia disorder do not therapy for insomnia (CBTi), as Insomnia criteria is the consideration capture all individuals who meet self‑reported usage is low, and cost is of patients with pain which either diagnostic criteria and should be a consideration limiting its use. prevents sleep onset, or contributes avoided as indicators of insomnia to wake after sleep onset, as the two in future studies as they likely differ slightly on inclusion criteria. underrepresent prevalence in the population.

4 Chronic Insomnia Disorder in Australia TABLE OF CONTENTS

3 EXECUTIVE SUMMARY 10 Chronicity of sleep difficulties 14 Worry about sleep 6 INTRODUCTION 10 Clinically significant distress 14 Chronicity or impairment in functioning 6 Prevalence of clinical 14 Opportunity to sleep by age insomnia according to clinical 10 Adequacy of habitual sleep and sex opportunities diagnostic criteria is unclear 15 Overall prevalence of chronic 6 Help‑seeking behaviours 10 DSM‑V specific exclusion of insomnia disorder in the and treatment response coexisting medical conditions Australian population for insomnia are not well 11 DSM‑V reference to 16 Sociodemographic understood coexisting mental health characteristics of individuals 7 Ongoing monitoring of sleep conditions and substance use meeting diagnostic criteria problems in the Australian explaining sleep problems; for chronic insomnia disorder community rationale for retaining in Australia participants with mental 18 Motivations for seeking help health and substance use 7 AIMS from a Healthcare Provider in the definition of chronic for Sleep 8 METHODS insomnia disorder 9 Definitions of Insomnia used 19 Use of sleep aids, apps and for Analyses (ICSD‑3 and 12 RESULTS therapeutic approaches DSM‑V) 12 Prevalence of insomnia in Australians with chronic according to diagnostic insomnia disorder 10 Detailed notes about criteria (DSM‑V and ICSD‑3) identifying Insomnia in the 19 Sleep disruption in the survey 13 Prevalence of insomnia broader community sleep symptoms and 10 Difficulties Initiating or 20 REFERENCES insomnia‑related daytime Maintaining Sleep (DIMS) manifestations

LIST OF LIST OF TABLES FIGURES

17 Table 1: Distribution of 19 Table 4: Prevalence 13 Figure 1: Prevalence ≥1 insomnia (%, n) classified by of sleep aid, app, sleep symptoms (3+ times/ DSM-V and ISCD‑3 criteria and therapeutic week) reported by the in relation to participant engagement by sample across age groups demographics insomnia in the 15 Figure 2: Prevalence of Australian population 18 Table 2: Prevalence of ≥1 daytime symptoms (3+ insomnia (%, n) in relation to 19 Table 5: Prevalence times/week) reported by the activities conducted in the (%, n) of sleep sample across age groups hour before attempting sleep disruption 15 Figure 3: Overall (experienced ≥3 18 Table 3: Factors prompting prevalence of chronic nights/week) participants (n=613) to insomnia disorder in the discuss sleep problems with Australian population a health practitioner (n=2,044)

A Report to the Sleep Health Foundation 5 INTRODUCTION Chronic insomnia disorder (insomnia) represents a significant burden for both the individual, and for the Australian healthcare system.

Insomnia is one of a number of PREVALENCE OF such as the Athens Insomnia Scale22. sleep disorders which contributes To date, no studies have considered to the $66.3 billion dollar cost of CLINICAL INSOMNIA prevalence at a population level poor sleep in Australia (2016–17)1. ACCORDING TO CLINICAL comparing current diagnostic Insomnia has been associated with DIAGNOSTIC CRITERIA IS criteria (ie the DSM‑V and ICSD‑3; 2–5 23 increased risk of hypertension , UNCLEAR see Sateia for brief summary). coronary heart disease6, heart Consistency in establishing failure7, cardiovascular mortality8,9, There is a paucity of studies that prevalence of ‘clinical insomnia’ in the impaired glucose metabolism10 and have examined the prevalence Australian community is poor, and a diabetes11. Epidemiologic data has and correlates of insomnia using likely contributor to the large range also shown an association between definitions that correspond to in published prevalence estimates insomnia and elevated inflammatory these contemporary classifications. to date. This can be addressed markers (CRP)12,13, which has been Globally, prevalence estimates of by asking questions in population linked to cardiopulmonary mortality14. clinical insomnia vary substantially. studies which allow for identification In contrast, a recent meta‑analysis In an Australian context, prevalence of insomnia against both clinical found insomnia was not related estimates vary widely between 5–33% diagnostic criteria (DSM‑V and/or to overall mortality15. Insomnia is of the population21. While global ICSD‑3). highly comorbid with a number of indications are that prevalence of psychiatric diseases, particularly insomnia symptoms is rising, the HELP‑SEEKING depression, and some evidence veracity of this statement in the BEHAVIOURS AND suggests insomnia may contribute to Australian context is unclear. The incident depression16. most recently published Australian TREATMENT RESPONSE estimates from Bin, Marshall and FOR INSOMNIA ARE NOT The American Academy of Sleep Glozier (2012)21 date from the Medicine (AASM) 17,18 defines chronic WELL UNDERSTOOD 2007 National Mental Health and insomnia as a perceived difficulty Wellbeing Survey (n=8,841) and Despite the individual and societal with sleep initiation, consolidation, 22,24 reported the prevalence of insomnia burden from insomnia , studies duration, or quality despite adequate is 5.6% in Australians aged 16–85. across countries including Australia opportunity to sleep, plus subsequent Insomnia was determined from have shown relatively few people daytime impairment, lasting at a single response item, and did seek help for insomnia and sleep least three months. The daytime 25 not account for the duration and problems more broadly . Effective consequences encompass a wide frequency of symptoms experienced treatment of insomnia is complicated variety of issues, including significant which makes alignment of symptoms by two important considerations: distress or impairment in social, with current diagnostic criteria to occupational, educational, academic, establish prevalence difficult. 1) the under‑recognition and behavioural or other important under‑diagnosis of insomnia, and areas of functioning. Subsequently, One of the key challenges in classifications of insomnia in both determining the prevalence of 2) heterogeneous treatment the International Classification of chronic insomnia at a population pathways for patients who do Sleep Disorders (ICSD‑3)19 and the level is the diversity in definitions receive a diagnosis of insomnia Diagnostic and Statistical Manual employed to characterize ‘insomnia’, Morin26 highlights that treatment of Mental Disorders (DSM‑5)20 have and the parameters used to identify trajectories for patients with been simplified and are largely respondents with insomnia in insomnia are diverse, and are congruent with the AASM insomnia population studies. Measures can dependent on a variety of factors definition, although both require the vary from single item assessment of unique to the individual. These can symptoms to occur at a frequency of insomnia symptoms, to composite include socioeconomic factors, three or more times per week. scores based on a variety of scales

6 Chronic Insomnia Disorder in Australia AIMS

the type of healthcare provider The current research was who initiates treatment, and how accessible treatment options are for commissioned by the Sleep Health patients. Despite this awareness, Foundation in order to: limited research has considered the help‑seeking behaviours of patients with insomnia. There is a Determine the prevalence clear need for better insight into of insomnia disorder in the the treatment options patients with 1 insomnia access, perceived success of Australian population according these options, and importantly, how to established diagnostic criteria regularly gold‑standard treatment options are accessed by those who could benefit. Compare prevalence rates using both the Diagnostic ONGOING MONITORING 2 and Statistical Manual of OF SLEEP PROBLEMS Mental Disorders, Fifth Edition IN THE AUSTRALIAN (DSM‑5) and the International COMMUNITY Classification of Sleep Disorders, Research commissioned by the Sleep Health Foundation in 2016 identified Third Edition (ICSD‑3) the prevalence of both clinical and behavioural sleep problems in the Identify the sociodemographic 27–29 Australian community . Findings correlates of insomnia disorder from this survey have informed the 3 2017 Deloitte’s report ‘Asleep on in Australia (including gender, the Job’30, and were heavily cited in ethnicity, socioeconomic status, the first of its kind 2019 Parliament of Australia report on sleep health location) awareness. The prevalence of sleep problems in the community was striking, and warrants regular and Determine the prevalence of consistent follow‑up in order to help‑seeking behaviour in identify trends over time related to 4 Australians who meet diagnostic sleep health in Australia. criteria for clinical insomnia

Establish the prevalence of alternate sources of sleep 5 disruption (snoring, sleep apnoea and restless legs)

A Report to the Sleep Health Foundation 7 METHODS

The survey was conducted over the Numerous survey questions were period March to April 2019 on behalf retained from the 2016 Australian of the Sleep Health Foundation, and Sleep Health Foundation population funded by Merck, Sharp and Dohme. sleep survey27. The 2016 survey The study was developed, designed included questions from: and executed by epidemiologists from Flinders University (Professor • 2002 US National Sleep Foundation Robert Adams, Dr Sarah Appleton), Sleep in Adults survey The University of Adelaide (Dr Tiffany • 2005 Australian Sleep in Adults Gill) and CQUniversity Australia (Dr survey Amy Reynolds), and distributed online by Dynata (formerly Research Now The 2019 Australian Sleep Health 27 SSI) as per the 2016 survey . Foundation population sleep survey additionally included: Dynata employ a three‑stage randomization process when • Detailed questions to facilitate recruiting participants from their identification of respondents panel of >250,000 Australian experiencing chronic insomnia participants to reduce risk of bias. disorder according to current, This process has been reported published DSM‑V and ICSD‑3 27–29,31 elsewhere . Briefly, participants definitions; are randomly invited from panels of eligible Australians, with a small • Health service use and information remuneration benefit associated with specifically for help seeking completion. The survey begins with related to sleep; and profiling questions randomly selected for completion. Participants are then • Questions related to treatment matched to suitable surveys, with access for sleep disorders. the sleep survey completed here one of the options, after randomization. The questionnaire used is provided Invitations for participants take the at Attachment 1. The survey form of emails, banners, messaging methodology was approved by the and text alerts from the operator. University of Adelaide Office of Invitation text varies from respondent Research Ethics, Compliance and to respondent, in order to reduce Integrity’s Human Research Ethics the potential for language to bias Secretariat (H‑2018‑214). participation. The invitation to Results reported in the following participate does not disclose the report have drawn on existing and general content of the survey in order new questionnaire items in order to to reduce self‑selection bias. address the intended objectives of The sample closely matched the the commissioned study. All analyses Australian population for age, were conducting using IBM SPSS gender, area of residence, income version 25.0 (IBM Corporation, and workforce participation, Armonk, NY, USA). Differences in the according to ABS data. There were distribution of predictors between more people with higher education participants with and without (Bachelor degree or higher 34% vs insomnia were explored using the 2 22% in the population overall) in the Pearson χ statistic. participant sample.

8 Chronic Insomnia Disorder in Australia DEFINITIONS OF INSOMNIA USED FOR ANALYSES DSM‑V (ICSD‑3 AND DSM‑V) INSOMNIA DISORDER

Complaint of dissatisfaction with sleep quantity or quality associated with ≥1 of the following:

1. Difficulty initiating sleep

ICSD‑3 2. Difficulty maintaining sleep (frequent awakenings, or problems returning to sleep CHRONIC INSOMNIA DISORDER after awakenings)

Patient (or parent/caregiver) reports: 3. Early‑morning awakening with inability to return to sleep 1. One or more of: • Difficulty initiating sleep Disturbance causes clinically significant distress • Difficulty maintaining sleep or impairment (social, occupational, educational, academic, behavioural or other important areas • Waking earlier than desired of functioning) • Resisting bed on an appropriate schedule • Difficulty sleeping without parent/caregiver Frequency: ≥3 nights per week. intervention Duration: ≥3 months. 2. Daytime consequences (one or more): Occurs despite adequate opportunity for sleep • Fatigue/malaise • Attention, concentration or memory Is not better explained by, and does not occur impairment exclusively during, the course of another • Impaired social, family, occupational or sleep‑wake disorder (e.g. narcolepsy, academic performance breathing‑related sleep disorder, a circadian rhythm sleep‑wake disorder, parasomnia) • Mood disturbance/irritability • Daytime sleepiness Coexisting mental disorders and medical • Behavioural problems (e.g. hyperactivity, conditions do not adequately explain the impulsivity, aggression) predominant complaint of insomnia • Reduced motivation/energy/initiative Insomnia is not attributable to the physiological • Proneness for errors/accidents effects of a substance (e.g. drug of abuse, • Concerns about, or dissatisfaction with, sleep medication)

3. Adequate opportunity and circumstances to sleep

4. Duration: ≥3 months

5. Frequency (symptoms): ≥3 times/week

6. The sleep/wake difficulty is not better explained by another sleep disorder

A Report to the Sleep Health Foundation 9 DETAILED NOTES ABOUT than 3 months; At least 3 months but Impairment in occupational function less than 6 months; At least 6 months was determined by identifying IDENTIFYING INSOMNIA but less than 1 year; 1 year or more; participants making errors at least IN THE SURVEY Refused/Don’t know. one day in past 3 months: “Thinking about the past three months, how To avoid any bias in self‑report of For the ICSD‑3 definition of insomnia, many days did you make errors at insomnia symptoms, participants chronicity of reported specific work because you were too sleepy or were asked a series of detailed daytime impairments experienced you had a sleep problem? Response questions about difficulties initiating three or more times per week (see options were: None; 1 to 2 days; 3 to and maintain sleep, chronicity of their below), were identified with the 5 days; 6 to 10 days; More than 10 sleep difficulties, clinically significant following question: You indicated that days; Refused/don’t know. distress or impairment in functioning, you’ve had difficulty within the past and adequacy of their habitual sleep month. For about how long have you ADEQUACY OF HABITUAL durations. had this difficulty? Possible response options were: Less than 1 month; At SLEEP OPPORTUNITIES DIFFICULTIES INITIATING least 1 month but less than 3 months; Adequate opportunity for sleep was OR MAINTAINING SLEEP At least 3 months but less than 6 identified with an all/most of the time (DIMS) (BOX 1) months; At least 6 months but less response to “Does your current work than 1 year; 1 year or more; Refused/ schedule or typical weekday routine, DIMS occurring at least three Don’t know. including your duties at home, allow nights per week were identified by you to get enough sleep?” with other the following questions: “We are CLINICALLY response options being sometimes; interested in asking you some specific SIGNIFICANT DISTRESS rarely/never; don’t know/refused. questions about what your sleep has OR IMPAIRMENT IN been like over this past month. In DSM‑V SPECIFIC the past month how often have you FUNCTIONING (BOX 2) experienced these things? 1) Difficulty EXCLUSION OF The sleep disturbance causing falling asleep, 2) Waking a lot during COEXISTING MEDICAL clinically significant distress or the night, 3) Waking up too early impairment in social, occupational, CONDITIONS and not able to get back to sleep”. educational, academic, behavioural, Responses options were Rarely or Further classification according to or other important areas of never; A few nights a month; A few DSM‑V required the exclusion of functioning and occurring three or nights a week; Every or almost every coexisting medical conditions such more times per week were identified night. as pain that explain the predominant by the following questions: “ We are complaint of insomnia. These also interested to hear about your CHRONICITY OF SLEEP respondents were identified with typical daytime feelings over this past the following questions: 1) How often DIFFICULTIES month. In the past month how often does pain stop you from going to have you experienced these daytime Chronicity of the sleep difficulty (at sleep at night? 2) How often does feelings? Experienced feelings pain wake you up at night? Response least 3 months) was determined with of: 1) Sleepiness that interfered the following question regarding options were Never/rarely; A few with daily activities; 2) Felt sleepy nights a week (1–3 nights/week); the specific sleep difficulty for those sitting quietly day/early evening; 3) reporting any DIM symptom a few Most nights (4–6 nights/week); Every Fatigue or exhaustion; 4) Irritable night; Don’t know. nights/month or more: “You indicated or moody; 5) Reduced motivation or that you’ve had difficulty with of your energy; 6) Reduced concentration, Participants responding most nights/ sleep in the past month. For about attention, memory; 7) Hyperactive, every night to one or both of these how long have you had this difficulty? impulsive, aggressive; 8) Had little questions were removed from Possible response options were: Less interest/pleasure in doing things; the insomnia category for DSM‑V than 1 month; At least 1 month but less 9) Felt down, depressed, hopeless. definition purposes.

10 Chronic Insomnia Disorder in Australia DSM‑V REFERENCE TO COEXISTING MENTAL HEALTH CONDITIONS AND SUBSTANCE USE EXPLAINING SLEEP PROBLEMS; RATIONALE FOR RETAINING PARTICIPANTS WITH MENTAL HEALTH AND SUBSTANCE USE IN THE DEFINITION OF CHRONIC INSOMNIA DISORDER

The DSM‑V definition of chronic insomnia disorder indicates that diagnosis is appropriate if coexisting mental disorders and medical conditions do not explain the predominant complaint of insomnia. For mental disorders, this is challenging to establish in cross‑sectional population data, as many mental health conditions and substance use conditions are preceded by reports of poor sleep (e.g. Jackson et al.32; Roberts & Duong33), and this relationship is bidirectional, with lifelong depression and anxiety from childhood linked to subsequent diagnosis of insomnia in middle age (e.g. Goldman‑Mellor et al.34). Similarly, there are prospective associations between poor sleep (shorter duration and greater daytime sleepiness) and onset of substance use (alcohol and marijuana) in adolescents35. For this reason, respondents with diagnosed mental health conditions were not removed from the insomnia classification, as it was not possible to establish without interview whether mental health conditions and substance use were driving insomnia symptoms in the sample.

A Report to the Sleep Health Foundation 11 RESULTS

PREVALENCE OF INSOMNIA ACCORDING TO DIAGNOSTIC CRITERIA (DSM‑V AND ICSD‑3)

In line with previous findings from the However, in both definitions, one 2016 Sleep Health Foundation Sleep of the criteria for diagnosis is that Survey, many Australian adults report participants must experience sleep difficulty initiating or maintaining onset/maintenance concerns and sleep, or daytime consequences daytime symptoms in the context of of poor sleep. Specifically, 40.4% adequate opportunity to sleep at (n=826) of respondents indicated night. Only half of the respondents sleep onset/maintenance concerns in the 2019 SHF Insomnia survey and daytime symptoms consistent (51.2%, n=1047) reported that their with a diagnosis of chronic insomnia daily routine provides adequate disorder according to the DSM‑V. opportunity to sleep all or most of This prevalence is marginally lower the time, which is indicative of social, when applying ICSD‑3 criteria for occupational or other lifestyle related sleep onset/maintenance concerns pressures on sleep opportunities. and daytime symptoms to the sample This is an important consideration for (38.6%, n=788). appropriately classifying participants with insomnia. Of those with insomnia symptoms (sleep onset/maintenance concerns and daytime symptoms), 60% did not have adequate opportunity to sleep.

48.8%  reported that their daily routine does not provide adequate opportunity to sleep all or most of the time.

12 Chronic Insomnia Disorder in Australia BOX 1: BOX 2: SLEEP SYMPTOMS DAYTIME SYMPTOMS (3 OR MORE (3 OR MORE TIMES/WEEK) TIMES/WEEK)

3AM

4AM

2AM 4:00

Felt Reduced memory, Felt Difficulty fatigue or attention or irritable falling asleep exhaustion concentration or moody

3AM

4AM

2AM 4:00

Sleepiness which Felt down, Hyperactive, Waking a lot interferes with depressed or impulsive or during the night daily activities hopeless aggressive

3AM

4AM

2AM 4:00

Waking up too Little interest Sleepy sitting Reduced early and can’t or pleasure in quietly – daytime motivation get back to sleep doing things or early evening or energy

A Report to the Sleep Health Foundation 13 PREVALENCE OF WORRY ABOUT SLEEP

SLEEP SYMPTOMS Significantly more female AND DAYTIME respondents than male respondents MANIFESTATIONS reported “often or always” worrying about getting a good night’s sleep The prevalence of sleep symptoms by 47% of those 65 years and over, (31% vs 21%) and being overwhelmed and daytime difficulties experienced compared with 22% of 18 to 24 year by thoughts when trying to sleep (35% three or more times a week (‘high olds. Difficulty falling asleep was vs 25%). These symptoms occurring frequency’) was high across the reported by 32% of 18 to 24 year olds frequently is more prevalent among survey population. Over half (59.4%) and 25% of those 65 years and over. younger adults and declines in of respondents overall report at least frequency as people age. Among one sleep symptom experienced In contrast, experiencing daytime 18–24 year olds, 43% report being with high frequency (see Box 1 for symptoms three or more times a overwhelmed by thoughts when included sleep symptoms). The week differed significantly by sex trying to sleep, compared to 18% of prevalence of high frequency sleep (p<0.05) and by age (p<0.001). This those aged at least 65 years. symptoms did not differ by sex (57.2% is reflected in higher prevalence of males and 61.4% of females) or in females (71.5%) than males CHRONICITY age (see Figure 1). There were minor (54.9%) of reporting one or more differences across age groups, of the daytime symptoms three or In most people, ‘high frequency’ and no age-related increase in more times per week (see Box 2). sleep symptoms were chronic (having experiencing any sleep symptom There was a significant decline in persisted for at least 3 months or three or more times a week. age‑related prevalence of at least more). The prevalence of chronic one daytime symptom reported 3+ (≥3 months), ‘high frequency’ (three However, the type of symptom varied, times/week from 80.2% in 18–24 year or more times a week) was 50.4% with waking up overnight or early in olds to 45.2% of 65+ year olds. The (n=1031). The prevalence of chronic the morning more common in older age‑related prevalence can be seen high frequency symptoms did not people and difficulty falling asleep in Figure 2. differ by sex, but did by age; sleep more frequent in the young. Waking symptoms (DIMS) are more likely to up a lot overnight was reported be chronic in older people.

FIGURE 1: FIGURE 2: Prevalence > 1 sleep symptoms Prevalence of > 1 daytime (3+ times/week) reported by symptoms (3+ times/week) reported the sample across age groups by the sample across age groups

100 100

80 80

60 60

40 40 PERCENTAGE 20 PERCENTAGE 20

0 0 18-24 25-34 35-44 45-54 55-64 65+ 18-24 25-34 35-44 45-54 55-64 65+

AGE GROUP AGE GROUP

14 Chronic Insomnia Disorder in Australia KEY MESSAGES

FIGURE 3: Older age is not synonymous Overall prevalence of chronic insomnia with higher prevalence of disorder in the Australian population 1 sleep symptoms commonly from the 2019 SHF Study (n=2,044) associated with insomnia.

400 The prevalence of at least one sleep symptom 3+ times/ 300 week is consistent across age,

200 although the type of symptom varies with age. 100 NUMBER OF PEOPLE NUMBER OF Sleep symptoms are more 0 7.5% (153) 12.2% (250) 14.8% (303)  likely to be chronic with age. Self-reported DSM-V ICSD-3 2 insomnia Insomnia Insomnia (doctor diagnosed) One of the primary differences between DSM‑V 3 and ICSD‑3 Insomnia criteria is the consideration of patients OPPORTUNITY TO SLEEP with other medical conditions BY AGE AND SEX which either prevents sleep Male respondents are far more likely than female onset, or contributes to wake respondents to report adequate opportunity to sleep (all/ almost all of the time) – 60.4% compared with 42.7% of after sleep onset. female respondents. The difference is most marked in the 25 to 44 year old age bracket. Adequate opportunity There is a need to use to sleep increases significantly with age, being reported by 40.5% in the 18–24 year age group and 74.2% in consistent definitions for those 65 years and older. Given that the frequency of 4 identifying insomnia if we are insomnia‑related sleep symptoms varies little across age groups, it is apparent that a greater proportion to adequately map changes is attributable to the weekday routine limiting sleep in prevalence and success of opportunity among younger adults than it is in those older, future treatments across time. and in female respondents than in male respondents, with corresponding effect on overall insomnia prevalence. Single item questions about OVERALL PREVALENCE OF CHRONIC diagnosed chronic insomnia INSOMNIA DISORDER IN THE 5 disorder do not capture AUSTRALIAN POPULATION all individuals who meet The prevalence of insomnia in the general Australian adult diagnostic criteria and should population differs dependent on the diagnostic criteria applied, and is noticeably higher when defined using a be avoided as indicators of composite score based on symptoms than when relying on insomnia in future studies as individual self‑report of a diagnosis (see Figure 3). There are clinical, practical and methodological considerations they likely underrepresent associated with these differences. prevalence in the population.

A Report to the Sleep Health Foundation 15 SOCIODEMOGRAPHIC treatment of the sleep problem likely to ICSD‑3 criteria, but not DSM‑V differs if the cause is restricted sleep criteria. Highest prevalence rates CHARACTERISTICS OF (inadequate sleep opportunity) versus were in those who indicated they INDIVIDUALS MEETING chronic insomnia disorder. spend more than they earn/receive DIAGNOSTIC CRITERIA (17.8%, ICSD‑3), and in those who Prevalence of chronic insomnia FOR CHRONIC INSOMNIA indicate they ‘get by’ (17.0%, ICSD‑3). disorder was higher in rural/regional In contrast, prevalence rates were DISORDER IN AUSTRALIA areas compared with metropolitan relatively consistent between areas, and in households that spoke 11.6–13.1% according to DSM‑V Prevalence of chronic insomnia English as the primary language at criteria; the exception being lower disorder relative to the home, according to both diagnostic rates in those who responded that sociodemographic characteristics criteria. Insomnia was significantly they ‘don’t know’ (7.8%, DSM‑V; of respondents from the 2019 less common among people who 6.8%, ICSD‑3). For both definitions, Insomnia Survey are provided by reported they were born in North, prevalence was higher in those who both definitions (DSM‑V and ICSD‑3) South, or East Asia (5%). Highest were not partnered (13.7% DSM‑V, in Table 1. These data suggest education level attained was 17.2% ICSD‑3) but the difference chronic insomnia disorder is greatly associated with prevalence, but compared to partnered relationships influenced by sociodemographic only according to ICSD‑3 diagnostic was only significantly different factors, irrespective of diagnostic criteria, where prevalence was according to the ICSD‑3 diagnostic criteria used to define prevalence. highest in individuals who identified a criteria. trade qualification (20.9%) and lowest In brief, insomnia was more prevalent in respondents who left school after No significant differences were in males than females (17.1% v 12.7%) 16 but were presently still studying observed between states by either according to the ICSD‑3 insomnia (7.9%). definition. criteria. No sex differences were observed when DSM‑V diagnostic Work status and household income Prevalence of insomnia by activities criteria were used with both males were both associated with prevalence in the hour before bed was consistent (13.0%) and females (10.9%) reporting of chronic insomnia disorder by across both definitions (Table 2). similar prevalence of insomnia. definitions. Groups reflecting highest The prevalence of insomnia was Females are less likely than males to prevalence did differ according lower with higher frequency of some report adequate opportunity to sleep. to diagnostic criteria applied. activities before bed, including work This largely accounts for the lower For DSM‑V criteria, the lowest relating to their job, and hot bath prevalence of chronic insomnia in prevalence of insomnia was observed or shower before bed. In contrast, female respondents compared with in volunteers (8.3%) and full‑time prevalence was higher in those who male respondents. workers (8.5%) while the highest frequently watched TV during the prevalence was in unemployed hour before bed. Prevalence according to both (16.6%) and retired (17.5%) workers. In definitions varied significantly contrast, according to ICSD‑3 criteria, PREVALENCE OF SEEKING according to age group, increasing the lowest prevalence was in full‑time HELP FOR SLEEP FROM A significantly among those 55 years workers (9.8%) and current students and older. (11.9%), while highest prevalence was HEALTHCARE PROVIDER in retired respondents (21.9%) and Adequate opportunity to sleep is Less than a third (30.0%, n=613) of those unable to work due to disability lower among young adults. As this is respondents overall reported that (22.9%). This difference is likely a an essential criterion for defining and they have discussed sleep with any reflection of the definition differences diagnosing insomnia, this influences doctor or healthcare professional around existing medical conditions insomnia prevalence rates in younger in the past year. Of this subgroup, experiencing pain. age groups. In addition, daytime 21.7% (n=133) met the ICSD-3 criteria sleepiness as the only reported Prevalence of insomnia differed for diagnosis with chronic insomnia daytime impairment is significantly across household income brackets. disorder. There were no differences higher among those aged 65 years According to both definitions, in frequency of conversations about and older. Consequently, prevalence prevalence was highest in the sleep with a doctor or other health of insomnia is inflated in older age $40–$60,000 per annum bracket. professional between those who did groups, and lower in younger age Prevalence differed in the lowest and did not meet criteria for insomnia groups. It is plausible that insomnia household income bracket by diagnosis. Most people who had rates could be higher in younger definition, with 6.6% of respondents spoken about sleep with a doctor or age groups than we routinely see experiencing DSM‑V chronic health professional indicated they (i.e. an insomnia phenotype) which insomnia, while over double (13.2%) in had discussed sleep 2-5 times in the would become more apparent if this bracket met ICSD‑3 criteria. last year. This frequency did not vary adequate sleep opportunity were significantly by whether they met routinely available. The importance Prevalence differed by both financial ICSD-3 insomnia criteria (63.2%) or of recognizing this is that the stress and marital status according did not have insomnia (58.8%).

16 Chronic Insomnia Disorder in Australia TABLE 1: Distribution of insomnia (%, n) classified by DSM-V and ISCD-3 criteria in relation to participant demographics DSM-V insomnia ICSD-3 insomnia % n % n Sex Male 13.7 136 17.1* 170 Female 10.9 114 12.7 132 Other 0.0 0 0.0 0 Age (years) 18 to 24 11.2 26 11.6 27 25 to 34 10.3 39 11.6 44 35 to 44 7.6 30 9.3 37 45 to 54 11.4 39 14.6 50 55 to 64 15.4 48 20.3 63 65 to 74 16.1 40 20.5 51 75+ 20.9*** 28 23.1*** 31 State ACT 6.3 2 9.4 3 NSW 9.9 58 12.9 75 NT 0.0 0 0.0 0 QLD 14.4 58 17.2 69 SA 13.5 30 17.5 39 TAS 16.9 12 21.1 15 VIC 11.3 58 12.9 66 WA 15.2 32 17.1 36 Region Metro 11.2 159 13.5 191 Rural/ regional 14.5* 91 17.8* 112 Language at home English 13.0* 243 15.7* 294 Other 4.1 7 5.3 9 Highest education Still at school 8.0 2 12.0 3 High school or less 14.6 67 17.0 78 Left after 16 still studying 7.9 3 7.9 3 Trade 15.2 25 20.6*** 34 Certificate/Diploma 13.6 86 17.5 111 Bachelor degree/higher 9.4 65 10.4 72 Work status Full-time 8.5** 52 9.8*** 60 Part-time 12.6 50 13.5 55 Student 10.3 12 11.9 13 Homemaker 12.2 23 14.4 27 Unemployed 16.6 24 17.6 24 Retired 17.5 73 21.9 93 Unable to work due to disability 10.7 11 22.9 24 Volunteer 8.3 1 17.9 1 Other 15.4 4 18.8 6 Household income <$20K 6.6** 10 13.2*** 20 >$20k-$40k 15.8 62 20.2 79 >$40k-$60k 17.3 60 21.4 74 >$60k-$80k 12.8 31 16.5 40 >$80k-$100k 10.1 22 11.5 25 >$100-$150k 11.1 33 10.7 32 >$150k 7.5 11 8.2 12 Financial stress Spend more than earn/get 12.9 29 17.8* 40 Get by 13.1 74 17.0 96 Bit left over (saved or spent) 12.2 110 14.0 126 Saves a lot 11.6 29 13.5 34 Marital status No partner 13.7 115 17.2* 143 Partner 11.3 135 13.3 159

Note: * p<0.05; ** p<0.01; *** p<0.001 within each diagnostic criterion.

A Report to the Sleep Health Foundation 17 KEY MESSAGES

Sociodemographic correlates SELF-REPORTED 1 of insomnia differ according to DOCTOR-DIAGNOSED the diagnostic criteria applied to INSOMNIA

determine chronic insomnia disorder. The prevalence of self-reported It will be important to use consistent doctor‑diagnosed insomnia varied criteria over time to meaningfully little across age groups (25 to 34 years – 7.4%; 65 to 74 years – 6.8%), determine changes in prevalence and although it was higher in 18 to 24 correlates of insomnia in future studies. year olds (12.5%). Doctor-diagnosed insomnia was more common in female respondents (8.6%) than male Lower income, financial stress, respondents (6.2%). unemployment, and retirement are MOTIVATIONS FOR 2 associated with highest prevalence SEEKING HELP FOR SLEEP rates of insomnia in the Australian Of the respondents in our sample population; and when the ICSD‑3 who met ICSD-3 diagnostic criteria, criteria are applied, rates are higher in less than half (43.9%, n=133) indicated those unable to work due to disability. they had discussed sleep with any healthcare provider in the preceding 12 months. Of the 133 respondents Rates of insomnia are higher who had discussed sleep, over half according to both criteria in older (56.4%) indicated that discussions 3 about sleep problems with health Australians; despite no apparent practitioners were initiated by the change in prevalence in overall sleep healthcare professional. Respondents who met criteria for chronic insomnia symptoms, and a decline in daytime disorder were more likely than those symptoms with age, in the population who did not to report they were aware of feeling sleepy/unfocussed more broadly. (43.6% versus 31.5%, p=0.009). Other factors prompting participants Daytime sleepiness as the sole to discuss sleep problems are summarized in Table 3; however daytime impairment is far more these did not differ significantly 4 common among older adults. This in those with and without ICSD-3 suggests the insomnia phenotype insomnia. differs across age groups, with the “hyperarousal” phenotype much less common in the elderly.

Prevalence of insomnia is relatively unaffected by activities in the hour 5 before bed, with similar rates in those who routinely use technology, work, eat, drink alcohol or are on social media frequently compared to those who do not.

18 Chronic Insomnia Disorder in Australia TABLE 2:

Prevalence of insomnia (%, n) by diagnostic criteria DSM-V insomnia ICSD-3 insomnia in relation to activities conducted in the hour before attempting sleep. % n % n Did work relating to job 3 nights/month or less 13.2 221 15.8 265

≥3 nights/week 8.6* 26 11.2* 34

Were on internet 3 nights/month or less 11.2 74 13.8 91

≥3 nights/week 12.8 176 15.5 212

Used social media: 3 nights/month or less 12.8 125 16.0 157 FB, Twitter, Instagram ≥3 nights/week 12.0 125 13.9 145

Watched TV 3 nights/month or less 9.1* 46 10.9** 55

≥3 nights/week 13.4 203 16.3 247

Read 3 nights/month or less 11.7 158 14.0 189

≥3 nights/week 13.5 91 16.6 112

Drank alcoholic beverage 3 nights/month or less 12.5 204 14.7 239

≥3 nights/week 11.8 46 16.2 63

Took hot bath, shower 3 nights/month or less 13.6* 175 16.5* 213

≥3 nights/week 10.2 75 12.3 90

Had meal/snacks 3 nights/month or less 13.3 166 15.6 195

≥3 nights/week 11.1 83 14.2 106

Note: * p<0.05; ** p<0.01.

TABLE 3:

Factors prompting participants (n=613) to discuss sleep No insomnia ICSD-3 insomnia problems with a health practitioner comparing those without insomnia to those with ICSD-3 criteria insomnia. % n % n I felt unwell physically 28.1 135 30.1 40

Felt unwell emotionally (moody, etc) 36.0 173 38.3 51

Aware of feeling sleepy/unfocussed 31.5 151 43.6** 58

Worried about ability to do tasks (e.g. job, other tasks, driving) 27.1 130 25.6 34

Family member or friend suggested speak to a health professional 16.9 81 14.3 19

Health professional initiated discussion on sleep 36.7 176 56.4*** 75

Worried about sleep, although wasn’t feeling tired during the day 11.5 55 6.8 9

Other 9.0 43 7.5 10

Note: ** p<0.010; *** p<0.001.

A Report to the Sleep Health Foundation 19 USE OF SLEEP AIDS, APPS AND THERAPEUTIC APPROACHES IN AUSTRALIANS WITH CHRONIC INSOMNIA DISORDER

Sleep aid, app use and therapeutic Use of online modules or sleep apps engagement is relatively consistent was low across the sample, with in Australia irrespective of whether a usage <10% overall for those with and person meets the criteria for insomnia without insomnia. Similarly, cognitive or not. However, prescription sleep behavioural therapy (CBTi) from a medication usage ≥3 nights/week was healthcare professional was low, with significantly higher in participants who 6.8% of those with no insomnia, and met the ICSD‑3 diagnostic criteria 8.7% of those who met the insomnia (12.3%) than in those who did not criteria indicating they had used CBTi (7.8%). for insomnia either a few nights/ month, or more.

TABLE 4: Prevalence of sleep aid, app, and therapeutic engagement by insomnia status in the Australian population. No insomnia ICSD-3 insomnia % n % n Herbal supplements such as Valerian never/rarely 91.5 1561 89.7 270

few nights/month 4.6 78 5.3 16

≥3 nights/week 3.9 67 5.0 15

Sleep medication prescribed by a doctor never/rarely 86.4 1478 80.8* 244 (e.g. temazepam, valium) few nights/month 5.8 100 7.0 21

≥3 nights/week 7.8 133 12.3 37

Online modules or sleep apps, including never/rarely 92.3 1568 91.0 274 insomnia apps few nights/month 4.1 70 3.3 10

≥3 nights/week 3.6 61 5.6 17

Cognitive behavioural therapy (CBTi) never/rarely 93.3 1584 91.3 274 techniques for insomnia from a health care professional few nights/month 3.4 57 5.0 15 ≥3 nights/week 3.4 57 3.7 11

Note: * p<0.05.

20 Chronic Insomnia Disorder in Australia KEY MESSAGES

SLEEP DISRUPTION IN THE BROADER Relatively few Australians speak COMMUNITY 1 to healthcare professionals Monitoring of sleep disruption about sleep, despite almost is important to highlight areas half of the population reporting requiring public education and future intervention in the field inadequate sleep. of sleep health. The prevalence of frequent sleep disruptions Even amongst patients who self‑reported in our representative sample of the Australian meet diagnostic criteria for population are provided in Table 5. 2 chronic insomnia disorder, sleep is often only discussed as a secondary issue during a consultation for other reasons.

TABLE 5: Concern about competency (at Prevalence (%, n) of sleep 3 work, and on the road) is one of disruption (experienced Prevalence the least frequent motivations > a few nights/week).* for discussing sleep with a % n healthcare professional in the Doctor diagnosed sleep apnoea 6.4 131 (with sleep study) small sub‑sample who had discussed sleep in the last year. Frequent or loud snoring 17.1 351 This is despite awareness of Breathing pauses in sleep 10.0 203 feeling sleepy or unfocussed. Restless legs (≥ few nights/week) 19.7 402 Prescribed medication use 10.7 219 Treatments for insomnia Failure to get adequate or 64.9 1326 are rarely/never used; there satisfactory sleep’ 4 is untapped potential for

Note: *Can have more than one. increasing usage, particularly of gold standard CBTi if engagement with healthcare providers can be increased.

Usage rates suggest a need for greater education or awareness 5 to promote use of gold standard treatment (CBTi) in insomnia, as self‑reported usage is low.

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