TY  - JOUR
PY  - 2021//
TI  - A blue-enriched, increased intensity light intervention to improve alertness and performance in rotating night shift workers in an operational setting
JO  - Nature and science of sleep
A1  - Sletten, Tracey L.
A1  - Raman, Bhairavi
A1  - Magee, Michelle
A1  - Ferguson, Sally A.
A1  - Kennaway, David J.
A1  - Grunstein, Ronald R.
A1  - Lockley, Steven W.
A1  - Rajaratnam, Shantha M. W.
SP  - 647
EP  - 657
VL  - 13
IS  - 
N2  - PURPOSE: This study examined the efficacy of a lighting intervention that increased both light intensity and short-wavelength (blue) light content to improve alertness, performance and mood in night shift workers in a chemical plant. <br><br>PATIENTS AND METHODS: During rostered night shifts, 28 workers (46.0±10.8 years; 27 male) were exposed to two light conditions each for two consecutive nights (~19:00-07:00 h) in a counterbalanced repeated measures design: traditional-spectrum lighting set at pre-study levels (43 lux, 4000 K) versus higher intensity, blue-enriched lighting (106 lux, 17,000 K), equating to a 4.5-fold increase in melanopic illuminance (24 to 108 melanopic illuminance). Participants completed the Karolinska Sleepiness Scale, subjective mood ratings, and the Psychomotor Vigilance Task (PVT) every 2-4 hours during the night shift. <br><br>RESULTS: A significant main effect of time indicated KSS, PVT mean reaction time, number of PVT lapses (reaction times > 500 ms) and subjective tension, misery and depression worsened over the course of the night shift (p<0.05). Percentage changes in KSS (p<0.05, partial η(2)=0.14) and PVT mean reaction time (p<0.05, partial η(2)=0.19) and lapses (p<0.05, partial η(2)=0.17) in the middle and end of night shift, expressed relative to start of shift, were significantly improved during the lighting intervention compared to the traditional lighting condition. Self-reported mood did not significantly differ between conditions (p>0.05). <br><br>CONCLUSION: Our findings, showing improvements in alertness and performance with exposure to blue-enriched, increased intensity light, provide support for light to be used as a countermeasure for impaired alertness in night shift work settings.<p />  <p>Language: en</p>
LA  - en
SN  - 1179-1608
UR  - http://dx.doi.org/10.2147/NSS.S287097
ID  - ref1
ER  -