Good Sleep Quality and Progressive Increments in Vigilance During Extended Night Shifts

Abstract

Objective: Assess the change in sleep and vigilance of underground miners during long periods of extended shifts. Methods: Seventy miners worked 14 consecutive 12-hour day and/or night shifts. Also, they wore an actigraph and completed a visual analog scale for vigilance four times per shift. Linear regression models with mixed effects were used. Results: Sleep efficiency was higher during day shifts than during night shifts (86,5 vs 85.5, P < 0.05) but sleep duration did not differ (6:34 vs 6:44, n.s.). Mean vigilance level at Time 3 (02h00) was significantly lower than that at Time 1 (19h00) during the first 10 night shifts whereas mean vigilance level at Time 4 (05h30) remained significantly lower for the 14 night shifts. Conclusions: Underground miners exhibit good sleep quality despite evidence of limited circadian adaptation in terms of nighttime vigilance.

Objective Assessment of Sleep Patterns among Night-Shift Workers: A Scoping Review

“…After reviewing the full text, we selected a final list of 32 studies ( Figure 1 ). Of these, 15 (46.9%) were cross-sectional surveys [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], 11 (34.4%) were RCTs [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ], 4 (12.5%) were quasi-experimental studies [ 35 , 36 , 37 , 38 ], and 2 (6.3%) were cohort design studies [ 39 , 40 ].…”

“…Overall, 2822 adults were included in the final 32 studies. The study population of night-shift workers included health care workers (n = 18, 56.3%) [ 10 , 12 , 13 , 15 , 18 , 21 , 24 , 25 , 27 , 29 , 31 , 32 , 33 , 35 , 36 , 38 , 39 , 40 ], production workers (n = 6, 18.8%) [ 11 , 14 , 19 , 20 , 22 , 30 ], transportation workers (n = 3, 9.4%) [ 17 , 20 , 28 ], mixed types of workers (n = 1, 3.1%) [ 23 ] and no specific types of workers (n = 4, 12.5%) [ 9 , 16 , 26 , 34 ].…”

“…Most studies (n = 24, 75%) [ 10 , 11 , 12 , 13 , 15 , 16 , 17 , 18 , 20 , 21 , 23 , 24 , 25 , 27 , 28 , 29 , 30 , 31 , 33 , 34 , 35 , 36 , 39 , 40 ] were published after 2011. The study types encompassed intervention evaluation studies (n = 15, 46.9%) [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ], observational studies (n = 16, 50%) [ 9 , 10 , 11 , 12 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 39 ,…”

“…Of the 32 studies that used devices to measure the sleep patterns of night-shift workers, 6 (18.8%) studies measured sleep patterns in a laboratory [ 9 , 13 , 14 , 26 , 29 , 32 ] and 26 (81.2%) performed measurements using a wearable device in daily living conditions [ 10 , 11 , 12 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 27 , 28 , 30 , 31 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 ]. None of the studies utilized laboratory tests and wearable sleep trackers together.…”

“…Among the 26 studies using wearable devices to measure sleep patterns, many used Actigraphy (n = 10, 31.3%) [ 15 , 19 , 20 , 22 , 24 , 25 , 27 , 34 , 36 , 39 ] or actiwatch (n = 10, 31.3%) [ 10 , 11 , 12 , 16 , 18 , 28 , 31 , 33 , 37 , 38 ] ( Table 1 ). Other devices included the Fitbit series (n = 3, 9.4%) [ 21 , 23 , 40 ], Somnowatch (n = 1, 3.1%) [ 30 ], ReadiBand (n = 1, 3.1%) [ 35 ], and home electroencephalography (n = 1, 3.1%) [ 17 ]. The duration of sleep measurement using wearable devices ranged widely from 3 days to > 4 weeks.…”