Driving fatigue increases after the Spring transition to Daylight Saving Time in young male drivers: A pilot study

The Spring transition to Daylight Saving Time (DST) has been associated with several health and road safety issues. Previous literature has focused primarily on the analysis of historical crash and hospitalization data, without investigating specific crash contributing factors, such as driving fatigue. The present study aims to uncover the effects of DST-related circadian desynchrony and sleep deprivation on driving fatigue, by means of a driving simulator experiment. Eighteen participants (all males, age range 21-30 years, mean = 24.2, SD = 2.9) completed two 50-minute trials (at one week distance, same time and same day of the week) on a monotonous highway environment, the second one taking place in the week after the Spring transition to DST. Driving fatigue was evaluated by analysing several different variables (including driving-based, physiological and subjective indices) and by comparison with a historical cohort of pertinent, matched controls who had also undergone two trials, but in the absence of any time change in between. Results showed a considerable rise in fatigue levels throughout the driving task in both trials, but with significantly poorer performance in the post-DST trial, documented by a worsening in vehicle lateral control and an increase in eyelid closure. However, participants seemed unable to perceive this decrease in their alertness, which most likely prevented them from implementing fatigue-coping strategies. These findings indicate that DST has a detrimental effect on driving fatigue in young male drivers in the week after the Spring transition, and provide valuable insights into the complex relationship between DST and road safety.

Being robbed of an hour of sleep: The impact of the transition to Daylight Saving Time on work engagement depends on employees' chronotype

OBJECTIVE

Worldwide, over 70 countries advance their clocks in spring to Daylight Saving Time. Previous research has already demonstrated that the clock change negatively impacts employees at work. However, this research implicitly assumed that the clock change affects everyone to the same extent. In the current study, we propose that the massively prevalent Daylight Saving Time transition may have an effect on employees' sleep and their work engagement that is dependent upon employees' chronotype.

METHODS

We conducted a longitudinal study with 155 full-time employees who filled out online surveys on three Mondays around the transition to Daylight Saving Time.

RESULTS

Results showed that the transition to Daylight Saving Time resulted in decreased work engagement measured 1day as well as 1week after the transition to Daylight Saving Time. Lower sleep quality (but not shorter sleep duration) partly explained this effect. The negative effect of the transition to Daylight Saving Time on work engagement 1day after the transition was more pronounced for employees with later chronotypes ("owls") than for those with earlier chronotypes ("larks").

CONCLUSION

In summary, our study shows that the transition to Daylight Saving Time has an adverse short-time impact on private life and working life and should, therefore, also be considered in organizations. Because later chronotypes are especially prone to adverse effects of the transition, interventions targeted for this group might be especially helpful.

Traffic crash changes following transitions between daylight saving time and standard time in the United States: New evidence for public policy making

INTRODUCTION

This study examined the impact of daylight saving time changes on traffic crashes in the United States. Using a data-driven regression analysis approach, the study analyzed 2014-2016 crash data from six states spanning all four major time zones in the contiguous United States.

METHOD

The researchers developed regression models for a number of analysis scenarios and by days of week separately. Based on the crash data, the team used an eight-week impact period for the spring time change and a four-week impact period for the fall time change.

RESULTS

The regression analysis showed that the spring time change was followed by an overall crash reduction of 18% during the eight-week period immediately after the time change, with a considerably higher crash reduction for freeway crashes (24%), rural crashes (24%), or non-intersection crashes (21%). The time change back to SDT in fall was followed by a 6% overall crash increase during the following four weeks, with considerably higher increases for freeway crashes (15%), non-intersection crashes (9%), nighttime crashes (28%), single-vehicle crashes (28%), and crashes in urban areas (12%). This study provides additional insights, including in many cases more comprehensive knowledge on how the changes to and from DST each year affect roadway traffic crashes.

PRACTICAL APPLICATIONS

The findings of this project further add to the current understanding on how the time changes affect public health in the form of traffic crashes. They also serve as additional evidence for public policy makers to better weigh the benefits and impacts associated with the time changes in the United States for relevant policy makings.

Effect of Daylight Saving Time clock shifts on white-tailed deer-vehicle collision rates

To devise effective measures for reducing hazardous wildlife-vehicle collisions, it is necessary to know when during the year accidents occur most frequently, and what factors cause the seasonal patterns. Daylight Saving Time (DST) 1-h clock-shifts around the spring and fall equinoxes at temperate zone latitudes are associated with increased vehicle accidents, attributed to driver error caused by disrupted sleep patterns and changes in visibility during peak driving times. Collision with deer is a significant cause of motor vehicle accidents in North America; in New York State alone, 65,000 vehicle accidents annually are caused by collision with white-tailed deer (Odocoileus virginianus). We asked whether white-tailed deer-vehicle collisions (DVC) increased in frequency after DST clock shifts in New York State, by analyzing 35,167 New York State DVC reports from 2005 to 2007. For the spring, when the clock is shifted an hour forward relative to sunrise (i.e. later sunrise and sunset), there was either no change or possibly a small decrease in workweek evening DVC after the clock shift. For fall, when the clock is shifted an hour back relative to sunrise (i.e. earlier sunrise and sunset), the DVC rate was far higher than spring. The DVC rate was higher after the clock shift than before, caused in part by an ongoing seasonal trend for increasing DVC associated with deer behavior around the time of rut, peaking about two weeks after the clock shift. However, there was also a reduction in workweek morning DVC after clock-shift, but an even greater increase in DVC in the evening. DVC rates are highest around dusk and during the fall, and the fall DST clock-shift caused more workweek commuter traffic to coincide with the annual hourly period of peak risk of DVC. We conclude that in New York State, DST clock-shift results in an increase in the number of DVC, and therefore injuries and property damage associated with such accidents. The justification for DST clock-shifts is controversial; when evaluating the benefits and costs, one should include the consequences for risk of wildlife-vehicle collisions, especially in regions where ungulate-vehicle accidents are frequent, and clock-shifts coincide with the rut or other periods of peak accident risk.

Daylight Saving Time: Pros and Cons

The original rationale for the adoption of daylight saving time (DST) was to conserve energy; however, the effects of DST on energy consumption are questionable or negligible. Conversely, there is substantial evidence that DST transitions have the cumulative effect on sleep deprivation with its adverse health effects. In light of current evidence, the European Commission in 2018 decided that biannual clock change in Europe would be abolished. Current indirect evidence supports the adoption of perennial standard time, which aligns best with the human circadian system and has the potential to produce benefits for public health and safety.

Daylight saving time does not seem to be associated with number of percutaneous coronary interventions for acute myocardial infarction in the Netherlands

Background

In multiple studies, the potential relationship between daylight saving time (DST) and the occurrence of acute myocardial infarction (MI) has been investigated, with mixed results. Using the Dutch Percutaneous Coronary Intervention (PCI) registry facilitated by the Netherlands Heart Registration, we investigated whether the transitions to and from DST interact with the incidence rate of PCI for acute MI.

Methods

We assessed changes in hospital admissions for patients with ST-elevation myocardial infarction (STEMI) or non-STEMI (NSTEMI) undergoing PCI between 1 January 2015 and 31 December 2018. We compared the incidence rate of PCI procedures during the first 3 or 7 days after the transition with that during a control period (2 weeks before transition plus second week after transition). Incidence rate ratio (IRR) was calculated using Poisson regression. Potential gender differences were also investigated.

Results

A total of 80,970 PCI procedures for STEMI or NSTEMI were performed. No difference in incidence rate a week after the transition to DST in spring was observed for STEMI (IRR 0.95, 95% confidence interval (CI) 0.87–1.03) or NSTEMI (IRR 1.04, 95% CI 0.96–1.12). After the transition from DST in autumn, the IRR was also comparable with the control period (STEMI: 1.03, 95% CI 0.95–1.12, and NSTEMI: 0.98, 95% CI 0.91–1.06). Observing the first 3 days after each transition yielded similar results. Gender-specific results were comparable.

Conclusion

Based on data from a large, nationwide registry, there was no correlation between the transition to or from DST and a change in the incidence rate of PCI for acute MI.

Human activity, daylight saving time and wildfire occurrence

Wildfires shape landscapes and ecosystems, affecting health and infrastructure. Understanding the complex interactions between social organization, human activity and the natural environment that drive wildfire occurrence is becoming increasingly important as changing global environmental conditions combined with the expanding human-wildland interface, are expected to increase wildfire frequency and severity. This paper examines the anthropogenic drivers of wildfire, and the relationship between the organization of human activity in time and wildfire occurrence focusing on the effects of transitions into and out of Daylight Saving Time (DST). DST transitions shift activity in relation to natural wildfire risk within a solar day, induce changes in the time allocated to wildfire-causing activities and disrupt sleep patterns. The paper estimates short and medium run effects of DST-induced changes in the temporal organization of human activity through a Regression Discontinuity Design with time as the running variable and Fixed Effects models, using data from over 1.88 million non-prescribed ignitions recorded in the contiguous US over 23 years. Estimates suggest that DST has a quantitatively and statistically significant immediate and medium-run effect on wildfire occurrence. Wildfire occurrence jumps by around 30% in the immediate aftermath of transitions into DST, adding about 98 human-caused wildfires across the contiguous US per year, while the transition's effect is detectable for 3 weeks. Transitions induce within-day temporal displacement of wildfires in a pattern compatible with the shifting of human activity mechanism, while the result cannot be attributed exclusively on disruptions in sleep patterns. Naturally arising lightning-strike wildfires do not respond to changes in civil time, while the results are robust to changes in assumptions. Results suggest that wildfire policy should account for the temporal organization of human activity.

Changes in atrial fibrillation admissions following daylight saving time transitions

BACKGROUND

Daylight saving time (DST) imposes a twice-yearly hour shift. The transitions to and from DST are associated with decreases in sleep quality and environmental hazards. Detrimental health effects include increased incidence of acute myocardial infarction (MI) following the springtime transition and increased ischemic stroke following both DST transitions. Conditions effecting sleep are known to provoke atrial fibrillation (AF), however the effect of DST transitions on AF are unknown.

METHODS

Admitted patients aged 18-100 with primary ICD9 code of AF between 2009 and 2016 were included. The number of admissions was compiled and means were compared for the Monday to Thursday period and the entire seven day interval following each DST transition and the entire year for the entire cohort and separated by gender. Significance was determined with Wilcoxon nonparametric tests.

RESULTS

Admission data for 6089 patients were included, with mean age of 68 years and 53% female. A significant increase was found in mean AF admissions over the Monday to Thursday period (3.09 vs 2.47 admissions/day [adm/d], P = 0.017) and entire week (2.48 vs 2.09 adm/d, P = 0.025) following the DST spring transition compared to the yearly mean. When separated by gender, women exhibited an increase in AF admissions following the DST spring transition (1.78 vs 1.28 adm/d for Monday to Thursday period, P = 0.036 and 1.38 vs 1.11 adm/d for entire week, P = 0.050) while a non-significant increase was seen in men. No significant differences were found following the autumn transition for the entire cohort or when separated by gender.

CONCLUSION

An increase in AF hospital admissions was found following the DST springtime transition. When separated by gender, this finding persisted only among women. This finding adds to evidence of negative health effects associated with DST transitions and factors that contribute to AF episodes.

Daylight saving time, circadian rhythms, and cardiovascular health

Very recently, the European Parliament, called to decide on possible abolition of the Daylight Saving Time (DST), approved a resolution calling the scientific community to conduct a more in-depth evaluation. The question is based on disruption of body's circadian rhythms. We review here the relationship between DST and cardiovascular health. The available evidence suggests the existence of an association between DST and a modest increase of occurrence of acute myocardial infarction, especially in the first week after the spring shift. Possible mechanisms include sleep deprivation, circadian misalignment and environmental conditions. The role of gender and individual preference in circadian rhythms (chronotype) will need further assessment.

Accident rates and the impact of daylight saving time transitions

One-third of nations have adopted some form of Daylight Saving Time (DST). Associated costs and benefits include impacts on accident rates. Using data from 12.6 million accident claims in New Zealand during 2005-2016, we model accident rates as a function of various date-based predictors including days before/after the start and end of DST, holidays, day of week, and month of year. This is the first study to consider multiple accident categories (Road, Work, Falls and Home & Community), and the first in the southern hemisphere. The start of DST is associated with significantly higher rates of road accidents (first day +16% and second day +12%). Evidence that accident rates for Falls and Home & Community decline (increase) prior to the start (end) of DST suggest potential behavioural adaption from anticipating the change. While Work accidents show limited impact from DST changes, they exhibit a significant decline over the course of the week (Friday 13% lower than Monday), whereas Road accidents exhibit a significant increase (Friday 19% higher than Monday). Our results have implications for both DST implementation and policy.

Parkinson's patients cope with daylight saving time

Disturbances of the circadian timing system following daylight saving time (DST) may influence the symptoms of Parkinson's disease (PD). To address this question, we compared the severity of motor fluctuations and non-motor symptoms both before and after the time change. Total daily "off-time" based on diaries, excessive daytime sleepiness (Epworth Sleepiness Scale), depressive symptoms (Beck Depression Inventory), and psychosis associated with PD were assessed both before and after the DST. Eighty-three PD patients (mean age, 67±7.7years; mean disease duration, 10.4±6.4years) were included. Thirty-six patients had motor fluctuations (mean daily "off-time", 4.8±2.4h/day). There was no significant variation of the total daily "off-time" (2.5±2.6h/day versus 2.5±2.7h/day), ESS (8.3±4.8 versus 8.1±4.9), BDI (10.4±6.2 versus 10.0±6.9), or PAPD (1.4±1.6 versus 1.1±1.6) scores (P>0.05) after DST. Our results suggest that PD patients cope relatively well with DST.