Actigraphy in studies on insomnia: Worth the effort?

Abstract

In the past decades, actigraphy has emerged as a promising, cost-effective, and easyto-use tool for ambulatory sleep recording. Polysomnography (PSG) validation studies showed that actigraphic sleep estimates fare relatively well in healthy sleepers. Additionally, round-the-clock actigraphy recording has been used to study circadian rhythms in various populations. To this date, however, there is little evidence that the diagnosis, monitoring, or treatment of insomnia can significantly benefit from actigraphy recordings. Using a case-control design, we therefore critically examined whether mean or within-subject variability of actigraphy sleep estimates or circadian patterns add to the understanding of sleep complaints in insomnia. We acquired actigraphy recordings and sleep diaries of 37 controls and 167 patients with varying degrees of insomnia severity for up to 9 consecutive days in their home environment.Additionally, the participants spent one night in the laboratory, where actigraphy was recorded alongside PSG to check whether sleep, in principle, is well estimated.Despite moderate to strong agreement between actigraphy and PSG sleep scoring in the laboratory, ambulatory actigraphic estimates of average sleep and circadian rhythm variables failed to successfully differentiate patients with insomnia from controls in the home environment. Only total sleep time differed between the groups.Additionally, within-subject variability of sleep efficiency and wake after sleep onset was higher in patients. Insomnia research may therefore benefit from shifting attention from average sleep variables to day-to-day variability or from the development of non-motor home-assessed indicators of sleep quality.

How patients with insomnia interpret and respond to the consensus sleep diary: a cognitive interview study

“…Most importantly, these devices do not capture a person’s experiences of sleep, which is crucial for diagnosing insomnia and assessing its severity [ 32 ]. Even some actigraphy that are specially calibrated to measure sleep, and that are scientifically validated have been shown to be unable to distinguish sleep diary variables, except total sleep time, between patients with insomnia and normal sleepers [ 33 ]. This also renders them ineffective as a sole assessment tool, hence, it is worthwhile to continue investigating possibilities and developing a more effective instrument for measuring subjective sleep.…”

Characteristics of macroscopic sleep structure in patients with mild cognitive impairment: a systematic review

“…This minimizes the effect of somatic micromotion on the results. Previous studies ( 82 ) have also suggested that Actigraphy is more suitable for sleep assessment in healthy subjects and that the accuracy of its algorithm begins to diminish as the degree of sleep disturbance increases, eventually affecting the results of the test. It has also been suggested that Actigraphy has a tendency to under-assess WASO and that applying physical activity recorders in conjunction with sleep diaries and adapting to a sleep-wearing pattern for 1–2 weeks before undergoing the test can help to improve its accuracy ( 83 ).…”

Do Sleep-Related Metacognitive Strategies Shape My Sleep? The Relationships between Strategies for Controlling Sleep-Related Intrusive Thoughts and Subjective and Objective Sleep Quality in Young Adulthood and Older Age

“…The use of polysomnography to more accurately examining objective sleep parameters is also recommended. Although actigraphy is a noninvasive and valid method to measure objective sleep-wake parameters and motor-based activity in the participant's home, it has some limits such as overestimating sleep quantity, as shown in certain clinical samples (people with sleep disorders or other clinical disorders) [62]. Future directions might then include studies that examine, alongside subjective sleep measures, objective sleep measures using polysomnography for assessing other micro-and macro-structural sleep parameters (e.g., waking after sleep onset, or sleep fragmentation index) and other psychological metrics (e.g., skin conductance or heart rate variability) for a more in-depth assessment of psychological and psychophysiological indices of using a sleep-related metacognitive strategy at bedtime.…”