Home electroencephalography reveals that relying on subjective sleep assessments may not be reliable.

A study published in the journal Proceedings of the National Academy of Sciences revealed that 66% of individuals who considered their sleep poor did not have objective sleep problems, while 45% of those who believed their sleep was adequate were objectively sleep-deprived.

This data highlights the inadequacy of subjective sleep assessments for early diagnosis and effective intervention in sleep disorders, emphasizing the critical importance of objective tools such as sleep electroencephalography.

Accurate sleep evaluation is essential for diagnosing and treating sleep disorders; however, the limited ability to recall sleep experiences makes objective measurements, like electroencephalography (EEG), indispensable. Despite this, clinically precise methods for measuring sleep in real-world conditions remain scarce.

For instance, insomnia is a sleep disorder characterized by difficulties in falling or staying asleep despite having the opportunity to do so. Typically, its diagnosis relies solely on self-reports. However, studies have shown that many individuals suffering from insomnia perceive their sleep duration to be significantly shorter than what objective measurements indicate.

This discrepancy between subjective and objective sleep assessments can lead to inappropriate treatment strategies, such as attempts to increase sleep duration in individuals who are already getting enough sleep.

Conversely, people unaware of their sleep disturbances may overlook early signs of serious sleep disorders.

To address these issues, S’UIMIN Inc., a startup affiliated with the University of Tsukuba, has developed home-use devices for sleep EEG that can conduct clinical-level sleep measurements. In this study, researchers conducted a comprehensive analysis of data collected from 421 individuals in Japan who were not receiving treatment for sleep disorders.

The dataset included home-based sleep EEG recordings over several nights, as well as responses to questionnaires assessing subjective sleep experiences. These subjective and objective evaluations were meticulously analyzed by physicians, after which researchers examined potential discrepancies.

The results revealed significant inconsistencies: 66% of individuals who rated their sleep as poor had no objective sleep issues, while 45% of those who considered their sleep adequate were identified as potentially sleep-deprived. Moreover, subjective assessments of "sleep quality" showed minimal correlation with objective indicators such as "sleep depth," "presence or absence of brief awakenings," and "presence or absence of sleep apnea risk."

This data underscores the importance of not relying solely on subjective assessments when evaluating sleep health. Incorporating objective metrics, such as sleep EEG data, into standard medical evaluations and providing personalized recommendations based on this data could enhance sleep habits and facilitate early detection of sleep disorders.