Author(s): SAEVARSDOTTIR, S., BJORNSDOTTIR, K., ARNARDOTTIR, N., JÓHANNSSON, E., GESTSDÓTTIR, S., Institution: UNIVERSITY OF ICELAND, Country: ICELAND, Abstract-ID: 2305

Introduction: Mid-adulthood is characterised by substantial occupational, familial, and social demands that may increase vulnerability to both sleep disturbances and mental health difficulties. While it is well established that sleep and mental health are closely linked and exercise affects both positively, most research focuses on single mental health outcomes. Less is known about how subjective sleep characteristics relate to different dimensions of mental health during mid-adulthood, a critical yet understudied life stage.
This study aims to first describe the prevalence and severity of mental health problems, sleep characteristics, and exercise frequency in mid-adulthood. Secondly, to examine whether subjective sleep characteristics show distinct associations with different dimensions of mental health, and lastly, to assess whether these associations vary by sex.

Methods: Cross-sectional data were drawn from the population-based cohort study The Health Journey. 460 adults born in 1988 and residing in Iceland answered an online questionnaire at age 36 about mental health, sleep and exercise frequency. Mental health was assessed using validated self-report measures of anxiety, depression, stress, and burnout. Subjective sleep characteristics included sleep problems (yes/no) and insomnia symptoms among those reporting sleep problems. Separate regression models examined associations between sleep characteristics and each mental health dimension. Models were adjusted for sociodemographic variables, including marital status, highest level of education, and average household income.

Results: 11.6% had moderate to severe frequency of anxiety symptoms, 19.7% had moderate to severe frequency of depressive symptoms, 48.6% had moderate to high symptoms of perceived stress, 18.9% had moderate to high levels of exhaustion, and 45.6% reported having sleep problems. No difference in exercise frequency was found between those with and without a sleep problem. The presence of sleep problems was negatively associated with all mental health outcomes. Significant associations for sex, favouring males, were found for anxiety, perceived stress, and burnout (all p < 0.05), but not for depression. No significant associations were found for the interaction between sleep problems and sex for any mental health outcomes.

Conclusion: Icelanders in mid-adulthood have a higher rate of mental ill health than the national average, along with a high prevalence of sleep problems. The presence of sleep problems was negatively associated with symptoms of anxiety, depression, perceived stress, and burnout. These findings highlight the need to address sleep behaviour in the context of mental health promotion especially since those with and without sleep problems did not differ in exercise frequency. Further studies identifying the mechanisms and causes of sleep problems in mid-adulthood are needed to provide optimal support for this population.