Gena Glickman - Academia.edu (original) (raw)

Papers by Gena Glickman

Sleep advances, Dec 31, 2022

Sleep, May 1, 2023

Introduction: A late bedtime is one of the most common characteristics of sleep habits in modern ... more Introduction: A late bedtime is one of the most common characteristics of sleep habits in modern society. This is also the case for schoolchildren, with negative consequences for their academic performance. Light exposure at night, particularly blue wavelength light, was thought to delay bedtime, and melatonin suppression via blue light was considered to be one of the mechanisms responsible for the delayed sleep phase. Methods: In the current study, we evaluated the effects of partial blue light blocking glasses (JINS Screen Lens Heavy [40%cut]) on salivary melatonin levels, sleep and circadian phase and daytime behavior (via actigraphs and questionnaires), with and without blue light blocking (JINS Standard Clean Lens) glasses in 39 male school children (ages between 10-12). The study design was a cross over design, with respective glasses worn for 3 hours before the habitual bedtime for two weeks, with a one-week washout period (with their own regular glasses) in between sessions. Saliva collections and questionnaires were performed during the first and second weeks of each session, with saliva collected-3,-2,-1, and 0 hours before the habitual bedtime. Actigraph data were collected throughout the evaluation periods. Results: We found that while partial blue light blocking glasses had no effect on salivary melatonin levels, they did significantly advance the sleep phase compared to the non-filter session (bedtime: 22.03±0.08h vs. 22.1±0.1h, sleep onset: 22.26±0.08h vs. 22.36±0.10h, p= 0.04). The filter effects were most noticeable in the second week, where significant advances in bedtime (-0.12h, p=0.03), sleep onset (-0.14h, p=0.03), wake up time (-0.13h, p=0.02), and leaving-bed time (-0.14h, p=0.02) from the 1st week were observed, whereas no changes were seen during the control session (without filter). Along with the sleep phase advancement observed, daytime irritability and acting out towards siblings and friends were significantly reduced in the second week of the filter session. Conclusion: Our results suggest that partial blue light blocking glasses advanced the sleep phase and improved behavior in schoolchildren, but that the effects were not mediated by changes in melatonin secretion. Further research into the mechanisms involved is warranted.

SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate,... more SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Research Square (Research Square), Mar 21, 2023

Training Network LIGHTCAP (project number 860613) under the Marie Skłodowska-Curie actions framew... more Training Network LIGHTCAP (project number 860613) under the Marie Skłodowska-Curie actions framework H2020-MSCA-ITN-2019, the BioClock project (number 1292.19.077) of the research program Dutch Research Agenda: Onderzoek op Routes door Consortia (NWA-ORC) which is (partly) financed by the Dutch Research Council (NWO), and the European Union and the nationals contributing in the context of the ECSEL Joint Undertaking programme (2021-2024) under the grant #101007319.

Additional file 1. Table S1: Participant characteristics. Table S2: Sleep, alertness, and readine... more Additional file 1. Table S1: Participant characteristics. Table S2: Sleep, alertness, and readiness by chronotype. Table S3: Correlations between chronotype, sleep, and mental health outcomes. Figure S1: Chronotype by age and compared to normative data.

Chronobiology International, 2020

Shiftwork is a significant risk factor for a host of negative health and safety outcomes, which h... more Shiftwork is a significant risk factor for a host of negative health and safety outcomes, which have been at least partly attributed to disturbances of the circadian timing system. As a result, an entire sub-field of chronobiology has been devoted to developing and evaluating countermeasures for circadian misalignment, sleep disruption, fatigue, and other issues associated with shiftwork. Much of this research takes place under highly controlled laboratory conditions due to the necessity of accurately characterizing individual rhythms, both for intervention design and assessment of efficacy. Applied studies of interventions for shiftworkers are, by their nature, more complicated, often demonstrating less consistent findings. While this, in part, reflects execution under less rigorously controlled conditions, it may also stem from variability in implementation approaches. A systematic review of published studies (through May 2017) of interventions designed to enhance circadian health in shiftworkers was conducted to determine the frequency and quality of the assessment of implementation as well as barriers and enablers to implementation. A search of PubMed, PsychINFO, Web of Science, and CINAHL databases yielded a total of 5368 unique references. After a title and abstract screen, 323 proceeded to full-text review; 68 of those met final criteria for data extraction. Implementation was assessed to some degree in 60.3% of those 68 articles. Where it was assessed, the mean quality score on a scale from 1 to 5 (1 = very little, 3 = moderate, 5 = very in-depth) was 2.56. One or more enablers were identified in just 17 of the 68 studies (25.0%), and barriers in just 18 (26.5%). Implementation of these interventions is a critical but seldom-acknowledged component of their uptake and effectiveness, and we highly recommend that future shiftworker intervention research make an effort to incorporate formalized assessments of implementation and/or hybrid effectivenessimplementation approaches.

Sleep, 2020

Introduction Sleep disturbance is prevalent among service members; however, little is known about... more Introduction Sleep disturbance is prevalent among service members; however, little is known about factors that impede sleep in unique operational environments, such as aboard naval ships. Given the importance of sleep to health and performance, identifying both causes and potential solutions to sleep disturbance is critical. The objective of this qualitative study was to elucidate barriers to sleep and the strategies U.S. Navy sailors use to improve their sleep and combat fatigue while underway. Methods Interviews were conducted with 22 active duty service members assigned to sea duty. The semi-structured interview guide assessed the experiences of service members sleeping in shipboard environments, including the strategies used to improve sleep and combat fatigue. Interview transcripts were analyzed using applied thematic content analysis by two independent coders. Results Most participants were male (91.8%) and enlisted (95.5%). The most commonly reported barrier to sleep was stre...

Frontiers in Neurology, 2021

In this review, we discuss the remarkable potency and potential applications of a form of light t... more In this review, we discuss the remarkable potency and potential applications of a form of light that is often overlooked in a circadian context: naturalistic levels of dim light at night (nLAN), equivalent to intensities produced by the moon and stars. It is often assumed that such low levels of light do not produce circadian responses typically associated with brighter light levels. A solid understanding of the impacts of very low light levels is complicated further by the broad use of the somewhat ambiguous term “dim light,” which has been used to describe light levels ranging seven orders of magnitude. Here, we lay out the argument that nLAN exerts potent circadian effects on numerous mammalian species, and that given conservation of anatomy and function, the efficacy of light in this range in humans warrants further investigation. We also provide recommendations for the field of chronobiological research, including minimum requirements for the measurement and reporting of light,...

Military Medical Research, 2021

Service members are at risk for sleep and psychological conditions affecting their readiness. Chr... more Service members are at risk for sleep and psychological conditions affecting their readiness. Chronotype (“morningness” or “eveningness”) is strongly associated with sleep, health and performance. The objective of this study was to examine associations between validated measures of chronotype and sleep quality, daytime functioning, alertness, and symptoms of depression, anxiety, and post-traumatic stress disorder (PTSD) in US service members (n = 298). Although predominantly young males (who skew toward eveningness in civilian populations), these Sailors skewed toward morningness (35.6% morning, 51.3% intermediate). Eveningness was associated with symptoms of depression and post-traumatic stress disorder (PTSD) (P

Nature and Science of Sleep, 2021

Introduction: Shiftwork causes circadian disruption and results in impaired performance, sleep, a... more Introduction: Shiftwork causes circadian disruption and results in impaired performance, sleep, and health. Often, individuals on non-standard shifts cannot modify work schedules. Athome sleep schedules are a potentially modifiable point of intervention, yet sleep-scheduling strategies remain relatively understudied. Specifically, the adoption of multiple strategies and the employment of strategies for not only night shifts, but also early starts on days, have yet to be formally examined to our knowledge. We studied how adoption of specific and/or multiple sleepscheduling strategies for day and night shifts relates to measures of adaptation to shiftwork, selfreported on-shift sleepiness, and individual characteristics (eg, age, chronotype, education in circadian and sleep health). We hypothesized: 1) strategies would differ by shift type, 2) individuals would adopt multiple strategies, 3) strategies better aligned with circadian principles would relate to measures of adaptation, and 4) individual characteristics, such as having dependents, would relate to strategy selection. Methods: A retrospective, online questionnaire (including items from the Survey of Shiftworkers and items related to sleep-scheduling strategies) was administered to both permanent and rotating hospital staff in four wards working 12-h day and/or night shifts (n=89). Additionally, reasons for strategy selection were explored. Results: Level of adaptation varied by sleep-scheduling strategy, with the least adaptation for those utilizing the Incomplete Shifter strategies. For night shifts, Night Stay and Switch Sleeper-N strategies were related to lower mid-shift sleepiness. Many night workers reported using strategies that restricted sleep, and most reported using multiple strategies, both of which also related to lower adaptation. Domestic considerations were the most common rationale for strategy selection. Strategies varied by several individual characteristics, including chronotype, dependents, and level of sleep education. Discussion: Future work should investigate sleep strategies and circadian interventions to help mitigate the effects of circadian and sleep disruption in hospital staff.

International Journal of Environmental Research and Public Health, 2022

Service members face unique barriers to sufficient and high quality sleep. In the present study, ... more Service members face unique barriers to sufficient and high quality sleep. In the present study, a circadian, light, and sleep skills program for shipboard military personnel (CLASS-SM) was designed to encourage and inform strategies that support optimal sleep and circadian health in the context of those barriers. Phase 1 included program development and refinement via an iterative formative evaluation, including structured interviews with service members and feedback from veterans and experts, resulting in further tailoring to the population. In Phase 2, the highly tailored program was administered to shipboard personnel (n = 55), and acceptability indicators were measured. Sleep- and circadian-related knowledge (pre- and post-program) and the perceived relevance of, and satisfaction with, program content (post-program) were assessed. Before the intervention, most individuals were unaware that 7–9 h of sleep is recommended (72%) and had little understanding of the physiological eff...

Neuro - endocrinology letters, 2002

The impact of breast cancer on women across the world has been extensive and severe. As prevalenc... more The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circ...

: Sleep disruption is a growing concern among military personnel. Very little is known, however, ... more : Sleep disruption is a growing concern among military personnel. Very little is known, however, regarding sleep characteristics of military members serving in combat environments. We sought to quantify the prevalence and cognitive correlates of sleep disruption among military personnel serving in a combat zone during Operation Enduring Freedom, utilizing a cross-sectional survey of active duty and reserve U.S. Navy personnel in the Afghanistan combat theater (N = 6,118). Survey sleep measures included total hours of sleep per day, total hours of sleep required to feel well-rested, difficulty falling asleep, and difficulty staying asleep. The survey also measured outcomes such as accidents related to the mission. Participants reported an average of 5.9 hours of sleep per night, despite requiring on average 6.8 hours to feel well-rested. Fifty-seven percent reported getting insufficient sleep, and this interacted with mission type. Sleep disruption was associated with number of deplo...

Frontiers in Neuroscience, 2021

In spite of the extraordinarily rapid development and high efficacy of the current vaccines, new ... more In spite of the extraordinarily rapid development and high efficacy of the current vaccines, new variants or other significant mutations may render them obsolete, and unfortunately, currently approved COVID-19 therapies have only modest efficacy and are not without risk and expense (Callaway, 2021). [...]it is imperative that we seek to mitigate the negative impacts of COVID-19 with every tool in our arsenal. Viral replication is also under circadian control, and though it has not been reported to our knowledge, SARS-CoV-2 almost certainly interacts with the host circadian system. [...]if the severity of COVID-19 symptoms and clinical outcomes are the result of a battle between viral replication and host immune response, enhancing circadian health in humans and capitalizing on temporal vulnerabilities of the virus via deliberately timed vaccination and treatment may also allow us to boost their efficacy and further reduce the severity of symptoms in those with COVID-19 (Besedovsky e...

Sleep, 2021

Sleep disturbance is pervasive among active duty military service members (ADSM) and has serious ... more Sleep disturbance is pervasive among active duty military service members (ADSM) and has serious adverse effects on performance and health. Interventions designed to improve sleep in operational settings are critical to maintain the health and readiness of this at-risk population. The objective of this study is to evaluate a novel sleep education program developed for ADSM. Participants were U.S. Sailors (N=150; 82.7% male, 35.3% <25 years old) assigned to either an intervention (44.7%) or control (55.3%) condition. Intervention participants attended the Circadian, Light, and Sleep Skills program for military personnel (“CLASS-M”). The 30-minute education program was designed to teach ADSM how to maximize sleep quality in operational environments. All participants completed a questionnaire at both baseline and 2 months post-intervention assessing demographics, sleep quality (Pittsburgh Sleep Quality Index; PSQI), sleep-related behaviors, knowledge and motivation. During the follo...

Neuro endocrinology letters, 2002

International Journal of Environmental Research and Public Health

Simple lighting solutions may mitigate the harmful effects of shiftwork. This hybrid effectivenes... more Simple lighting solutions may mitigate the harmful effects of shiftwork. This hybrid effectiveness–implementation study evaluated a multi-component lighting intervention in hospital nurses that included 6500 K architectural lighting in the nurses’ station plus optional behavioral components (a lightbox, blueblocker glasses, eyemasks) with instruction about appropriately timed usage. Selective improvements from baseline were observed in on-shift performance, sleep quality, and caffeine consumption in day workers (all p < 0.05); off-shift sleepiness scores improved for night workers (p < 0.05). Further, self-reported measures of quality of life improved for both groups (p < 0.05). Preliminary implementation data from interviews and questionnaires suggest perceived benefits and high acceptability of the intervention.