DARIEN, IL – A new study to be presented at the SLEEP 2026 annual meeting found that individuals with an evening chronotype, who prefer to go to sleep and wake up at later times, report poorer mental health, higher general loneliness, and higher nocturnal loneliness. Both forms of loneliness serve as significant pathways in the association between chronotype and mental health.
Results show that people with later sleep schedules reported significantly higher levels of anxiety. Feeling lonely at night helped explain this link: Evening chronotypes tended to experience greater nocturnal loneliness, which was in turn associated with higher anxiety. When nocturnal loneliness was accounted for, the direct relationship between chronotype and anxiety was no longer significant, and the indirect effect through nocturnal loneliness was significant, suggesting that nighttime loneliness is a key pathway connecting later sleep patterns to anxiety.
"People with later sleep patterns reported poorer mental health in part because they also experienced greater loneliness, including feelings of loneliness at night, and increased levels of anxiety," said lead author Alec Harlow, who is a researcher at Brigham Young University in Provo, Utah. "The findings suggest that both daytime and nighttime social experiences appear to be relevant when examining mental health among evening chronotypes."
Chronotype refers to an individual's natural preference for sleep and wake timing, and evening types — those who prefer later sleep and wake times — may be more prone to social misalignment with conventional schedules. According to the American Academy of Sleep Medicine, sleep is essential to health , and it requires adequate duration, good quality, appropriate timing and regularity, and the absence of sleep disturbances or disorders.
The study involved 442 participants recruited through the online research platform Prolific. Participants completed an online survey assessing chronotype using the Morningness-Eveningness Questionnaire, nocturnal loneliness using the Nocturnal Loneliness Scale, and anxiety using the Patient-Reported Outcomes Measurement Information System Anxiety Short Form. A structural equation model was used to test whether nocturnal loneliness mediated the association between chronotype and anxiety.
Harlow noted that the findings point to loneliness — and nocturnal loneliness in particular — as a potential intervention target for evening types.
"Evaluating and addressing loneliness, including the challenges that arise at night, such as anxiety, may represent a meaningful intervention target for therapists, clinicians, and researchers to improve the well-being of people with later chronotypes," Harlow said.
The research abstract was published recently in an online supplement of the journal Sleep and will be presented June 17 during SLEEP 2026 in Baltimore. SLEEP is the annual meeting of the Associated Professional Sleep Societies, a joint venture of the American Academy of Sleep Medicine and the Sleep Research Society.
