Kelly Sansom

Irregular sleep is increasingly related to poorer health, with stronger links to cardiovascular disease and mortality than sleep duration. Its impact on health-related quality of life, however, remains unclear, particularly in community-based populations. This study examined whether objectively measured sleep regularity is associated with physical and mental health-related quality of life. Sleep regularity was calculated using the Sleep Regularity Index from actigraphy data in 768 middle-aged to older adults from the Raine Study (median age [range] = 57 [53–61]; 58% female). Physical and mental health-related quality of life were assessed using the 12-item Short Form Health Survey. Quantile regression was used to examine associations at the 25th, 50th, and 75th percentiles, adjusting for age, sex, comorbidity count, sleep duration, and shift work. Median sleep regularity scores declined with self-rated health, from 77.17 (excellent) to 61.49 (poor). A 10-unit increase in sleep regularity was associated with higher mental health scores at the 25th (1.80; 95% CI: 0.90–2.60), 50th (1.20; 95% CI: 0.50–1.90), and 75th (0.50; 95% CI: 0.20–0.90) percentiles. For physical health, a 10-unit increase in sleep regularity was associated with a 1.20 (95% CI: 0.30–2.20) higher score at the 25th percentile, with no evidence of association at higher percentiles. These findings suggest that poorer sleep regularity is related to lower physical and mental health-related quality of life. Future research should explore whether improving sleep regularity can enhance quality of life in middle-aged to older adults.

Irregular sleep is increasingly related to poorer health, with stronger links to cardiovascular disease and mortality than sleep duration. Its impact on health-related quality of life, however, remains unclear, particularly in community-based populations. This study examined whether objectively measured sleep regularity is associated with physical and mental health-related quality of life. Sleep regularity was calculated using the Sleep Regularity Index from actigraphy data in 768 middle-aged to older adults from the Raine Study (median age [range] = 57 [53–61]; 58% female). Physical and mental health-related quality of life were assessed using the 12-item Short Form Health Survey. Quantile regression was used to examine associations at the 25th, 50th, and 75th percentiles, adjusting for age, sex, comorbidity count, sleep duration, and shift work. Median sleep regularity scores declined with self-rated health, from 77.17 (excellent) to 61.49 (poor). A 10-unit increase in sleep regularity was associated with higher mental health scores at the 25th (1.80; 95% CI: 0.90–2.60), 50th (1.20; 95% CI: 0.50–1.90), and 75th (0.50; 95% CI: 0.20–0.90) percentiles. For physical health, a 10-unit increase in sleep regularity was associated with a 1.20 (95% CI: 0.30–2.20) higher score at the 25th percentile, with no evidence of association at higher percentiles. These findings suggest that poorer sleep regularity is related to lower physical and mental health-related quality of life. Future research should explore whether improving sleep regularity can enhance quality of life in middle-aged to older adults.

Background
Behavioural and biological factors impacting healthy sleep can influence road and workplace safety. This study investigated the additive interactions of sleep-disrupting factors (sleep disorders, insufficient sleep, and shift work) on road and workplace safety in young adults (22 years) from the Raine Study.

Methods
Employed participants (n = 439, median age 22.0 years, IQR 21.6–22.3) were assessed for common sleep disorders (obstructive sleep apnoea, insomnia, restless legs syndrome). They provided information on shift work status, habitual sleep duration (insufficient sleep <7 h), and self-reported road and work incidents. A sufficient cause approach with inverse probability of overlap weights and logistic regression was used to study additive interactions.

Results
Sleepiness while driving was reported by 16 % and while at work by 11 % of participants. Insufficient sleep alone increased the odds of falling asleep while driving (OR 2.29; 95 % CI 1.17, 4.32). Three sleep-disrupting factors additively increased the risk of near-miss road incidents (β, 1.40 > 0). Sleep disorders with shift work was associated with the highest risk of falling asleep at work (relative excess risk due to interaction, RERI; 4.86; 95 % CI, 2.9, 6.81).

Conclusion
The combined burden of multiple sleep-disrupting factors including sleep disorders, insufficient sleep and shift work, is associated with an increased risk of near-miss road incidents and falling asleep at work. Given that sleepiness, both on the road and in the workplace, is common in young adults, there is a need for greater awareness and intervention to address the associated risks.

Background
Obstructive sleep apnea (OSA) severity often varies considerably from night-to-night, but whether environmental factors play a role is unclear. This study investigated seasonal and temperature-related changes in OSA severity.

Methods
Data were acquired from 70,052 participants with an average apnea-hypopnea index (AHI) ≥ 5 events/hour who used an under-mattress sleep sensor at least 4 times/week between January 2020 and September 2023. Fixed effect models were used to investigate the association between AHI and day of the year, adjusting for geographical location, variation in total sleep time, ambient temperature, and air pollution.

Results
Participants are middle-aged (mean ± SD, 53 ± 13 years), predominantly male (81%), overweight (BMI; 29 ± 6 kg/m2) and have an average of 492 ± 341 nights of data. Mean AHI is 18.0 ± 14.0 events/h and within-subject coefficient of variation is ±51%. AHI is ~5% higher during summer/winter compared to spring/autumn in the northern hemisphere, and 10–15% higher during summer compared to spring in the southern hemisphere. Higher ambient temperature (25th vs. 75th percentiles; 6 vs. 18 degrees Celsius) is associated with a 6.4% (95% CI; 6.3–6.5) increase in AHI. Results are consistent across 23 countries, although the effect of temperature on AHI is larger in Europe vs. the United States or Australia.

Conclusions
Here we demonstrate a seasonal component to OSA severity, partially explained by ambient temperature and seasonal variation in sleep duration. Our findings highlight the need to report data collection months in OSA clinical trials, and further study to uncover the physiology behind seasonal variation in OSA severity are required.

Sleep disorders are prevalent in shift workers but are commonly undiagnosed and unmanaged. This poses considerable safety, productivity, and health risks. There is limited education or early intervention to encourage awareness of, and treatment for, sleep disorders in young adults who will transition into careers requiring shift work. This study aims to investigate (a) the
of simulated shift work exposure and cognitive performance feedback for prompting help-seeking for sleep problems, and (b) the feasibility and acceptability of
this intervention for future healthcare workers. A hybrid type I effectiveness-implementation trial will be conducted from June 2024 to December 2025 with prospective healthcare workers currently enrolled in a medicine, paramedicine, or nursing degree. Ninety adults (18-39 years) who self-report sleep disturbances will be recruited and complete a combination of structured clinical interviews, screening questionnaires, remote monitoring technology, and overnight polysomnography (PSG). Participants will be randomized across three conditions, with varying exposure to a simulated transition to night shift without sleep, and cognitive performance feedback. All individuals will attend a diagnostic appointment with a sleep psychologist or sleep physician and discuss help-seeking pathways for their sleep. The primary outcomes will be help-seeking from a health professional for sleep (yes/no), time to help-seeking (days), and road safety-related events over 12 months. Process evaluation will explore the feasibility and acceptability of this approach from the participants' perspective.

Introduction: Irregular sleep is increasingly recognised as a correlate of adverse health outcomes, including cardiovascular disease, metabolic disorders, and all-cause mortality in large population-based studies. However, the association of irregular sleep, on quality of life (QoL) and mental health is yet to be established in large population-based studies particularly those that are representative of community populations. We aimed to address these associations in middle-aged adults from the Raine Study who are representative of the Australian community.

Method: Measures of sleep regularity, assessed by the sleep regularity index (SRI), were obtained from 808 middle-aged participants in the Raine Study (age [range], 57[42-82]; female=58%). SRI was calculated using actigraphy data from at least five consecutive 24-hour periods and SRI scores categorised by quartiles (lowest, irregular sleepers; middle two, mildly irregular sleepers; highest, regular sleepers). The relationships were determined between SRI; physical and mental component summary scores of QoL (Short Form Health Survey-12); depression symptoms (patient health questionnaire, PHQ9); and anxiety symptoms (generalised anxiety disorder, GAD7) using logistic regression adjusted for age, sex and shift work status. Specifically, adjusted logistic regression were used to examine associations between SRI groups with QoL (poor mental and physical component summary scores dichotomised by median) and depression (PHQ9 >9) and anxiety symptoms (GAD7 >9).

Results: Relative to regular sleepers, irregular sleepers had 1.6 (95%CI, 1.1-2.3) and 1.9-times (95%CI, 1.3-2.9) increased odds of poor mental and physical component summary scores of QoL, respectively. Irregular sleepers had increased risk of depression (3.9 (95%CI, 1.8-9.6)) and anxiety (2.84 (95%CI, 1.40-6.16)) symptoms relative to regular sleepers. There was no significant association of mildly irregular sleep with QoL and mental health outcomes relative to regular sleepers.

Conclusion: Behavioural interventions aimed at improving the regularity in sleep may be a feasible target to support improved QoL, depression, and anxiety symptoms in middle-aged adults.

Conflict of Interest: Yes- AJKP has received research funding from Delos and Versalux, and he is a director of Circadian Health Innovations PTY LTD.

Introduction: Disturbed sleep patterns are commonly reported among young adult university students, but limited evidence exists in community populations. This potentially introduces bias in our understanding of sleep patterns in early adulthood. We addressed this by characterising chronotype and sleep-corrected social jetlag (SJLsc) in a large, representative community population of 22-year-old adults and examined associations with quality of life (QoL).

Method: 867 participants (52% male, 22 years) from the Raine Study in Australia completed the morningness-eveningness questionnaire (MEQ) and self-reported bed and wake times on work and non-workdays. Linear regressions adjusted for sex and self-reported count of comorbidities were used to examine the association between chronotype and SJLsc (absolute difference between the sleep onset on free days and workdays; dichotomised by the median value) separately for physical and mental health sub-components of QoL according to the Short Form Survey (SF 12).

Results: Morning, intermediate and evening chronotypes were reported by 27%, 58% and 14% of the sample, respectively. Participants had a median SJLsc of 1 h (interquartile range, 0.5–2 h). In adjusted models, relative to morning chronotypes, evening chronotypes on average scored 2.7 units lower on physical (95% CI −4.0, −1.3; p < 0.001) and 4.8 units lower on mental health QoL (95% CI −6.9, −2.6; p < 0.001) sub-scales. There was no evidence of a meaningful association between SJL and QoL.

Conclusion: In young adults, evening chronotype is associated with poorer physical and mental components of QoL. These findings were not related to presence of SJL. Education and interventions to support the quality of life of evening chronotypes during early adulthood are likely needed.

Falls are a major cause of hospitalization fractures and functional decline in older adults. Obstructive sleep apnea (OSA), a highly prevalent sleep breathing disorder in older adults, has emerged as a potentially modifiable risk factor for falls. A small number of uncontrolled studies suggest OSA therapy by continuous positive airway pressure (CPAP) may reduce fall risk. We aim to describe the design of a randomized clinical trial that will evaluate if six months of CPAP intervention can significantly reduce fall risk markers in older adults with OSA.
140 adults aged ≥60 years at risk of falls with diagnosed and untreated OSA will be randomized to receive CPAP and usual care for fall risk or only usual care for fall risk. The primary outcome will be the difference in fall risk scores, derived from the physiological profile assessment, between the two arms six months post-randomization. Secondary outcomes will include differences in gait, quality of life, sleep quality (self-reported and objective home-based monitoring), psychological well-being, cognitive function, physical performance, muscle strength, and body composition at six months post-randomization.
Data will be analyzed on an intention-to-treat basis. Ethical approval was obtained from Southern Adelaide Clinical Human Research Ethics Committee in July 2023 (reference: 2023/HRE00081). Outcomes will be disseminated through publication in peer-reviewed journals and presentations at international conferences. Trial registration number: Australian New Zealand Clinical Trials Registry (ACTRN) 12623000965606.
The findings from this study will provide insight into the causal associations between OSA and fall risk and contribute to high quality evidence required to inform larger clinical trials and future guidelines for fall prevention.
•Obstructive sleep apnoea (OSA) is associated with balance and gait impairments which may increase the risk of injurious falls.•There is a lack of robust evidence from large, randomized control trials on whether treating OSA reduces the risk of falls.•We propose to address this by conducting a trial to evaluate if six months of OSA treatment improves fall risk.