The association between work interval regularity and sleep regularity: a 2-week observational study in daytime...

Area of Science:

• Occupational Health
• Sleep Science
• Chronobiology

Background:

• Irregular sleep patterns are linked to various health problems.
• The causes of irregular sleep among workers remain unclear.
• Work interval (WI) regularity is a potential determinant of sleep regularity.

Purpose of the Study:

• To investigate the association between work interval (WI) regularity and sleep regularity in Japanese daytime workers.
• To determine if irregular WI duration or timing contributes to irregular sleep.

Main Methods:

• 14-day observational study of 141 Japanese daytime workers (non-shiftwork).
• Daily self-reporting of WI duration, WI timing, time in bed (TIB), and bedtime.
• Calculation of regularity using standard deviation (SD) over 14 days; logistic regression analysis.

Main Results:

• Irregular WI duration (≥60 minutes SD) was associated with a 4.74-fold increased odds of irregular TIB (≥60 minutes SD).
• Irregular WI timing (≥60 minutes SD) was associated with a 7.71-fold increased odds of irregular bedtime timing (≥60 minutes SD).
• Significant dose-response relationship observed between WI regularity and sleep regularity.

Conclusions:

• Work interval regularity is significantly associated with sleep regularity among daytime workers.
• Recommendations include promoting regular WI to ensure worker health and sleep consistency.
• Workers experiencing irregular WI should actively strive to maintain regular sleep schedules.