The validity of Actiwatch2 and SenseWear armband compared against polysomnography at different ambient temperature conditions

Abstract

There were no validation studies on portable sleep devices under different ambient temperature, thus this study evaluated the validity of wrist Actiwatch2 (AW2) or SenseWear armband (SWA) against polysomnography (PSG) in different ambient temperatures. Nine healthy young participants (6 males, aged 23.3±4.1 y) underwent nine nights of study at ambient temperature of 17 °C, 22 °C and 29 °C in random order, after an adaptation night. They wore the AW2 and SWA while being monitored for PSG simultaneously. A linear mixed model indicated that AW2 is valid for sleep onset latency (SOL), total sleep time (TST) and sleep efficiency (SE) but significantly overestimated wake after sleep onset (WASO) at 17 °C and 22 °C. SWA is valid for WASO, TST and SE at these temperatures, but severely underestimates SOL. However, at 29 °C, SWA significantly overestimated WASO and underestimated TST and SE. Bland–Altman plots showed small biases with acceptable limits of agreement (LoA) for AW2 whereas, small biases and relatively wider LoA for most sleep variables were observed in SWA. The kappa statistic showed a moderate sleep–wake epoch agreement, with a high sensitivity but poor specificity; wake detection remains suboptimal. AW2 showed small biases for most of sleep variables at all temperature conditions, except for WASO. SWA is reliable for measures of TST, WASO and SE at 17–22 °C but not at 29 °C, and SOL approximates that of PSG only at 29 °C, thus caution is needed when monitoring sleep at different temperatures, especially in home sleep studies, in which temperature conditions are more variable.

Validity of Actigraphy in Measurement of Sleep in Young Adults With Type 1 Diabetes

“…Shin et al reported that using the medium threshold for Actiwatch2 provided minimal bias for SOL, TST, and SE but overestimated WASO at different ambient temperatures in a small group of healthy young adults. 3 Meltzer et al reported that the medium setting in healthy children provided results most similar to PSG. 6 Similarly, Ward et al reported that in healthy children as well as those with juvenile arthritis and asthma, the medium threshold setting provided the least biased results.…”

“…In a group of healthy adults, the Actiwatch2 underestimated TST at various ambient temperatures (7.1 to 17.6 minutes) and overestimated WASO (7.1 to 12.4 minutes) when using the medium setting. 3 Using the Actiwatch64 (Philips Respironics, Oregon, United States) device, an earlier Actiwatch model no longer on the market, Cellini and colleagues reported the low and medium threshold settings underestimated TST (by 1.1 to 4.7 minutes) whereas the high threshold produced results similar to the PSG. 1 These differences from the current findings may reflect that sleep is different in young adults with T1DM but also could be due to several factors, including differences in actigraphy devices and timing of sleep period (naps versus overnight).…”

“…In recent years, actigraphy has been used to objectively quantify sleep in the natural environment. This technique has been validated for use in healthy subjects [1][2][3] as well as in individuals with sleep disorders such as insomnia. 4 The Actiwatch2 (Philips Respironics, Oregon, United States) is a widely used actigraph worn on the nondominant wrist that has the capability to determine sleep and wake patterns.…”

“…5 It has been validated against PSG in healthy children 6 and adults. 3 Sleep parameters can be derived from Actiwatch2 recordings using three different threshold settings (low, medium, or high) for detection of wake-related accelerations (movements) before…”

Association between Daytime Activity, Fatigue, Sleep, Anxiety, Depression, and Symptom Burden in Advanced Cancer Patients: A Preliminary Report

“…In this study, actigraphy was offered as an elective procedure and also depending on the availability of Actiwatches. Actigraphy data were obtained using the Actiwatch2 34,35 (Philips Respironics; software: Actiware 6.02). We examined MDTA, which was calculated using total activity counts divided by total active time in minutes of Tuesday, Wednesday, and Thursday, during the first week of the study.…”