Fatigue management: a literature review.

Abstract

Fatigue management is a relatively new area in the health education and employee assistance (EA) field. While fatigue research has been conducted for years, insight into this complex health area has emerged only over the last two decades, and even less time has been devoted to determining practical program implications.

Fatigue is related to most other lifestyle habits and mental health conditions. For example, basic sleep principles and concepts can easily be incorporated into existing health education programs to show how they influence one another. Organizations operating in a 24/7 environment and industries employing safety-sensitive and shift work positions should give serious consideration to including fatigue management education in their health and safety and EAP programming. Besides the health and safety implications, a comprehensive fatigue management program can positively affect an individual's quality of life.

Several topical areas related to fatigue are reviewed in this paper, as well as literature explaining the relationship between risk factors and fatigue. Program implications for the transportation industry are outlined in a review of studies of the railroad industry An original study describes the impact of fatigue on the family life of shift workers. General guidelines and recommendations for EA professionals wanting to add fatigue management to their programs are included.

Introduction

Health and EA professionals have neglected fatigue as a significant risk factor, yet it is related to several other modifiable risk factors and lifestyle habits (Moore-Ede 1993; Rosa et al. 1990). There is clear evidence to suggest the problems caused by fatigue will get worse before they get better. For example, the number of Americans reporting trouble sleeping has risen 33 percent in recent years (Maas 1998). Fatigue and the ability to manage it affect health status and other aspects of an individual's well-being, such as work productivity, safety, and quality of life.

The intent of this article is to provide health and EA professionals with basic information about fatigue and offer recommendations to assist them in lowering the risks associated with fatigue. Specifically, this article will discuss the following areas: the scientific foundation and principles of sleep, sleep disorders, sleep deprivation, and the associated risk fatigues. Next, a discussion of the consequences of fatigue will consider their impact on individuals, families, organizations, and society. Literature specific to the railroad industry is reviewed to provide both scope and depth on how fatigue can be studied within an industry and how to address, through policies and programs, the issues arising from the research. Also included is an original study based on employee interviews and a discussion of the impact of fatigue on family and social life. The article concludes with a discussion of how EA professionals can apply the lessons of fatigue research in their organizations.

Scientific Foundation

The literature describes fatigue as a complex phenomenon that represents decreased ability to perform mental or physical tasks or respond after extended activity as well as decreased motivation to perform tasks. The level of fatigue experienced by an individual relates to past cumulative daily activity patterns and to periods of sleep and activity. In summary, fatigue results from time spent on tasks, natural circadian factors, and inadequate sleep (Brown 1994). Alertness, on the other hand, is the state of readiness and attentiveness achieved without artificial or natural enhancements.

Principles of Sleep

The scientific research on sleep is relatively recent and emanates from the pioneer work of Nathaniel Kleitman, who wrote a major volume on sleep in 1939 and conducted sleep research at the University of Chicago during the 1950s and 1960s. Kleitman's research resulted in discoveries related to sleep cycles, including the identification of the rapid eye movement (REM) stage of sleep (Dement 1992).

Sleep is a vital physical need and is defined as "a reversible behavioral state of perceptual disengagement from and unresponsiveness to the environment" (Carskadon and Dement 1989). Thus, sleep, for humans, performs a dual role of brain maturation and memory function and recuperation from physical fatigue (Brugne 1994). The REM stage of sleep is what most people refer to as "deep sleep." Actually, REM is associated with dreaming and represents restoration of mental functions (Carskadon and Dement 1989). Non-rapid eye movement sleep, which consists of four stages, represents the early stages of rest and provides physical recuperation. Information about the stages of sleep has important applications when designing work schedules and fatigue countermeasure strategies in operational settings.

Our internal circadian rhythms (our "regulating clock") comprise two key cycles that regulate our sleep patterns. The major cycle, representing the time we are most sleepy, generally lasts from 3:00 a.m. to 5:00 a.m. A secondary cycle, representing a less significant need for sleep, occurs approximately 12 hours later (3:00 p.m. to 5:00 p.m.).

The need for sleep is regulated by the hypothalmus. The suprachiasmatic nucleus, located in the hypothalmus, controls the circadian timekeeping mechanism. The sleep drive is similar to drives for thirst, hunger, and sex it serves to mobilize behavior that satisfies the underlying requirements. Consequently, the desire or drive for sleep becomes irresistible. This overwhelming drive or desire for sleep can happen at any time and even during activities, especially sedentary or monotonous activities.

Factors Affecting Sleep and Fatigue

Sleep disorders disrupt our sleep cycles and cause fatigue. Rothenberg (1997) reports that as many as 80 sleep disorders may independently coexist with emotional disorders, complicating treatment and diagnosis. Almost everyone experiences some sleep disruption in their life (Rothenberg 1997), and up to 49 percent of the adult U. S. population periodically reports problems with sleep (Maas 1998).

Failing to obtain adequate sleep results in excessive daytime sleepiness or fatigue that may lead to life-threatening conditions (Roth et al. 1989). Sleep deprivation compromises daytime functions and performance efficiency, and individuals experiencing sleep deprivation may also suffer other consequences of sleepiness (e.g., loss of energy, dysphoria, fatigue, lethargy, weariness, memory lapses, and lack of concentration and initiative.)

The factor that most consistently affects sleep patterns is age (Carskadon and Dement 1989). Aging contributes to less deep sleep, fragmented sleep, and difficulty recovering from sleep loss. According to Hirschkowitz, Moore, and Minhoto (1997), total sleep time declines throughout the life span even though sleep requirements remain the same as in young adulthood. As the workforce ages, the number of employees experiencing sleep disorders, fatigue, and daytime sleepiness will rise, causing concerns for employers and society.

Shift Work

A growing contributor to fatigue in society is the increasing reliance on non-traditional or "shift" workers. According to Rosa et al. (1990), shift workers comprise more than 25 percent of the U.S. working population. Employees required to work nontraditional shifts sleep shorter hours and also sleep more lightly, thus experiencing less restorative sleep. Studies confirm that daytime sleep is shorter in duration than nighttime sleep enjoyed by traditional day workers (Tepas and Carvalhais 1990). This sleep decrease translates into reduced alertness and job performance even among experienced shift workers and those who prefer shift work. The problem is exacerbated by the tendency of shift workers to return to "normal" sleep patterns on their off days, hampering their ability to set or reset their internal circadian clock.

Combating Sleep Loss

Alcohol is the leading sleep aid in the United States (Rosekind et al. 1996). Alcohol does help individuals get to sleep, but alcohol consumed before bedtime disrupts the ability to stay asleep and lowers the quality of sleep.

According to Maas (1998), four in ten Americans will cut back on sleep to participate in more activities or work longer. Dement (1992) reports that in cutting back on sleep, our society has become chronically sleep-deprived, but most people are not aware of the consequences. In short, sleep deprivation is an accepted social norm.

Health

Because lack of sleep and fatigue have negative effects on some of the primary risk factors for coronary heart disease (CHD), it should come as no surprise that a relationship is suggested between lack of sleep and CHD. This relationship becomes especially significant for shift workers--indeed, longitudinal studies of shift workers suggest their risk of CHD is three times greater than for their daytime counterparts (Knutsson et al. 1986).

Fatigue and stress are not synonymous conditions, but they do have similar symptoms and may exacerbate each other. While fatigue and stress are problems for many in society, they are especially problematic in combination with shift work or erratic schedules. Shift work and erratic work schedules are recognized stress factors in our 24-hour society (Sutherland and Cooper 1995). The symptoms of stress related to shift work include poor sleep during sleeping hours, sleepiness during work or waking hours, gastrointestinal problems, emotional disorders, irritability, and intolerance. Sleep disorders may also arise in response to stress.

Fatigue contributes to a sedentary lifestyle and is the third most common barrier (behind lack of time and a shortage of energy) to performing physical activity, Studies (Harman et al. 1988) and anecdotal evidence suggest that physical activity helps individuals sleep better, though performing physical activity too close to a sleep period may be disruptive. Moderate physical activity is an effective fatigue countermeasure strategy for individuals suffering from poor quality sleep and daytime sleepiness.

Some evidence suggests that what, when, and how much a person eats can influence sleep/wake cycles. Studies (Westfall-Lake and McBride 1998) have shown that avoiding certain foods and not eating heavy or large meals improve alertness and job performance.

Quality of Life

Research has demonstrated that shift workers have more complicated issues related to quality of life than day workers (White and Keith 1990; Simon i990). We now know that to fully address the issue of quality of life, attention and resources must be devoted to sleep/fatigue.

Sleep deprivation and sleep disruptions can significantly affect quality of life, including personal relationships and mental well-being. "Quality of life" refers to social and personal topics most employees deal with, such as family and relationship issues, participation in social and community events, and mental health.

According to Rosa et al. (1990), social and personal priorities, including relationship involvement, have changed significantly in recent years. One causal factor may be the increase in the number of dual-career families and single-parent households. In the last twenty years, our society has added approximately 158 hours per capita to our annual work and commute times. Additionally, working mothers have added almost 241 hours to their work and commute times since 1969 (Maas 1998). More increases in these times are expected, resulting in even more fatigue-related issues in the personal and professional lives of workers.

The difficulties these trends pose for the general population are exacerbated for shift workers and others who work irregular hours. Overall, day work appears to be more conducive to a high-quality family life than shift work. Day workers have demonstrated better overall mental health and integration into the family structure (Frost and Jamal 1979) and exhibited fewer disruptions in non-work activities and relationships (Khaleque and Rahman 1984) than shift workers. In another study, day workers reported better results in job satisfaction, marital satisfaction, family integration, social participation, and marital discord (Mott et al. 1965).

It has been documented that shift work negatively affects several areas of life: sleeping and eating routines, long-term relationships, dating, parental roles and patterns, sexual relations, and the level of stress on the family (Simon 1990). Shift work has been associated with significantly lower marital and relational happiness (Smith and Folkard 1993), and shift workers and their spouses report increased loneliness and a sense that the worker is being excluded from family events.

A contributor to the lower quality of marriage for shift workers is the negative effect on mood caused by fatigue and sleep deprivation (White and Keith 1990). Moreover, Hood and Milazzo (1984) suggest that work schedules have a ripple effect on an entire family, meaning that relational conflicts attributable to shift work may reverberate through family members (Simon 1990). Conflicts arise from such issues as a higher incidence of sexual problems, more disagreements, less interaction, more jealousy, and less psychological dependence on the spouse. Also, according to White and Keith (1990), an increasing number of shift workers socialize in an alternative sphere identified as the "nighttime community," increasing familial alienation and reducing commitment to a conventional lifestyle.

Shift workers often feel isolated because society views shift work as unusual. Shift workers report difficulty socializing with friends or dating, participating in cultural, social, religious, and political groups, attending evening or weekend gatherings, planning or attending community events, and gaining access to community services (Simon 1990). Irregular hours contribute to a sense of isolation and may adversely affect every aspect of social life (Walker 1978). Studies also suggest, however, that some individuals may self-select shift work because of the perceived advantages of working irregular hours.

Because individuals differ in their sleep requirements and ability to adjust to sleep reductions, the psychological effects of shift work vary significantly and may depend on individual tolerance (Regestein and Monk 1991). Current thinking suggests there may be a relationship between mental health and shift work. However, Cole, Loving, and Kripke (1990) noted that no longitudinal studies confirm that shift work causes psychological difficulties.

Theoretical discussions seek to determine if disruptions in circadian rhythms could induce psychiatric disturbances. Some studies have evaluated the effects of shift work and fatigue on substance abuse, neuroticism, and depression, but none are conclusive. In summary, evidence suggests that shift work, erratic hours, and fatigue may affect mental health, but it is inconclusive and has not been shown to be causal.

Fatigue in the Railroad Industry

Managing fatigue in the railroad industry is critical due to the erratic and mostly unscheduled nature of work shifts for train service employees (engineers and conductors). This section briefly describes six studies addressing fatigue in the railroad industry Five of the studies consider biological and performance issues; the last is an original case investigation of the effects of fatigue on families and significant others.

Literature Review of Key Studies

There are five classic studies discussing the effects of fatigue within the railroad industry. Before describing the studies, it is important to provide background information on federal legislation that governs work hours in the U.S. rail industry.

The Hours of Service Act (HOSA), enacted in 1907 and substantially revised in 1969, governs the on- and off-duty periods of railroad operating employees. Specifically, the law allows an employee to be on duty no more than 12 consecutive hours. Employees working less than 12 hours are entitled to 8 hours off duty, while employees on duty 12 or more hours are entitled to 10 hours off duty before commencing another duty period.

Trains today are heavier, longer, and faster than in 1907 and travel farther. Additionally, the working environment (industry technology) of the crews has changed, as have management philosophies on customer service.

Tepas (1994) criticizes current government regulations and collective bargaining agreements as outdated or unscientific in managing hours of service. Current regulations ignore both the time of day and human physiology, in effect treating all hours of the day equally regarding fatigue and alertness. Tepas suggests that long work hours are not necessarily a problem; instead, time of day and circadian rhythm considerations may have greater impacts on alertness and performance.

Simple solutions to the management of workplace alertness are not evident, and the issues are quite complex. Quick fixes like increased pay may only exacerbate the problem by attracting unfit workers to shift work. Therefore, new methods of managing work schedules and shift work practices need to be examined.

A study in France by Foret and Lantin (1972) was based on electroencephalogram (EEG) readings of train engineers in actual operational settings. The study was undertaken in response to engineers' concerns about safety, difficulties with interpersonal relationships (reportedly due to fatigue), and exhaustion. The study, which lasted one month, involved 10 train drivers who worked runs up to 250 miles. The engineers' work schedules varied daily and were described as irregular and not approximating recurrence.

Study results suggested the participants slept less than the general population while off-duty To compensate for their reduced sleep, they tended to nap more than the general population, but did not always recover from their sleep deficits. Participants who slept during morning hours woke up around noon no matter what time they went to bed, confirming the rigidity of the human circadian rhythm. In summary, time of day does seem to make a difference in alertness and sleep patterns.

Pollard (1996) conducted quantitative and qualitative assessments to determine how railroad scheduling practices affect the alertness and performance of train engineers. The study used data from diaries kept by engineers with six major U.S. railroads to determine quantity and quality of sleep, on-duty alertness levels, and major contributors to fatigue.

The study found that participants averaged approximately 20 minutes less sleep per day than the general population. Average daily sleep increased slightly with age, in part due to better assignments under seniority systems. Because engineers slept nights whenever possible, they did not adapt to daytime sleep to the extent permanent night-shift workers adapted. Engineers with assistants reported slightly more difficulty with alertness during critical circadian low points than drivers without assistants, suggesting that alertness increases when actively involved in performing a task.

Study participants were asked to suggest measures to mitigate fatigue. Fitness and wellness programs were recommended, as well as longer minimum rest periods (10 to 12 hours), duty limitations (no more than 10 consecutive hours), napping under controlled conditions, scheduled days off, established standards for hotels, and improved train information and crew calling systems.

Like other researchers, Pollard also noted the dominance of the circadian rhythm influence. Alertness and ability to obtain adequate sleep were both significantly affected by circadian rhythm considerations.

Thomas, Raslear, and Kuehn (1997) investigated the effect of work schedules on the alertness and performance of train engineers by using locomotive simulators to assess work schedules, rest, and performance requirements. Results showed progressive sleep deficits among all study participants. Performance decrements reached their nadir at approximately 3:00 a.m. in almost all cases, regardless of prior sleep. Alertness, as measured by the Multiple Sleep Latency Test, demonstrated fast sleep onset following duty periods (fast sleep onset is consistent with a large sleep debt).

The study concluded that time of day is a significant indicator of decreased alertness and performance and that work schedule variables are important determinants of job performance, including safety-sensitive tasks. The authors suggested that current federal regulations governing hours of service potentially permit work schedules that degrade the alertness and performance of train drivers.

Dawson et al. (1998) conducted 14 field-based studies at locations across Australia between 1995 and 1997. They collected reformation related to work schedules, alertness levels, sleep patterns, and biological adaptation. Measurement tools included actigraphs (wrist activity monitors), subjective sleep diaries, computer-based performance task tests, and urine samples (to measure melatonin secretion).

The studies showed that engineers obtain relatively little sleep during daytime hours, suggesting that measures be taken to ensure engineers' work schedules allow adequate time off between shifts (especially for engineers working shifts that require day sleep). The study also indicated that engineers who are required to work consecutive shifts may accumulate a considerable sleep debt. The combination of daytime sleep and accumulated sleep debt significantly affects alertness and performance. The authors recommended that time of day, rather than simply break duration, be considered in developing work schedules.

The study findings also demonstrated a high correlation between performance and alertness. Both performance and alertness were found to be relatively low during early-morning shifts. Time of day and length of sleep prior to work were shown to have significant effects on neuro-behavioral performance.

Participants in the study tended to attribute their fatigue to length of time on duty rather than its true cause, time of day On- and off-duty naps were recommended, as well as sufficient break periods between shifts.

Original Case Study

In an original qualitative research study, Holland (1999) explored the impact of fatigue on the lives of train engineers. The study involved in-depth, semi-structured interviews with 11 volunteer train engineers selected to generally match the demographics of the industry (see Table 1).

The overall intent of the study was to allow participants to describe their experience with fatigue and its effect on them, both professionally and personally The most salient issue to emerge from the interviews was the impact of fatigue on family relationships. The following major family-related themes emerged from the interviews:

1. Emotional issues that directly affect the family. These include anger, mood swings, and guilt and a corresponding need to somehow compensate for disruptions and alienation.

2. The need for family support. Participants expressed a need for increased family awareness of fatigue issues and believe it would result in a more supportive atmosphere, better coping skills, and reduced conflict. Family support thus represents both a concern and a solution.

3. Social implications. Fatigue and erratic work schedules caused both engineers and their partners to feel isolated and frustrated due to lack of a normal social life.

This study, specific to the railroad industry, demonstrates the biological, psychological, social, and performance disruptions evident in shift work, especially workers with erratic schedules. Together with the studies previously cited, it provides evidence of the rigidity of human circadian rhythms. The studies also demonstrate the complexities of managing fatigue in a shift work environment.

Implications for EAPs

In the United States, more than 26 percent of the workforce (a share that is increasing each year) works shifts or some form of a non-traditional schedule (Rosa et al. 1990). It is estimated that sleep deprivation and fatigue may cost society from $70 billion to $150 billion annually, with work organizations losing in excess of $20 billion annually through accidents, absenteeism, and lost productivity. Sleep deprivation and fatigue thus are "bottom line" workplace issues that affect recruitment and retention, absenteeism, productivity, performance, safety, and quality of life, creating important challenges for a variety of stakeholders, including managers and employee assistance and health professionals.

Supporting the Work Organization

By acquiring a fundamental understanding of fatigue and its effect on work organizations, employees, and families, EA professionals would be better able to communicate the risks of fatigue to both their organizational and individual clients. This would enable them to help shape policies, develop procedures that address the risks of fatigue and sleep deprivation, and implement an overall strategy for the effective management of fatigue. In addition, the cultural change principles that EA professionals apply to influence the environment surrounding other lifestyle habits would be applicable in the development of a fatigue management program. An example of a comprehensive fatigue management program is described by Leutzinger, Holland, and Richling (1999).

Training the Work Organization

Critical to the development of a fatigue management program is a comprehensive education program. Because fatigue is universal in our society (affecting not just shift workers), communication and education should extend to all employees.

Senior management should be among the first to receive orientation regarding the risks of fatigue. Without the buy-in of an organization's leadership, it is unlikely that comprehensive programs and the required cultural change will be supported.

The next group to receive education and orientation should be supervisors who directly manage shift workers. This group will be critical in supporting the required cultural change and delivering the education. In addition, managers and supervisors need to understand how fatigue and sleep deprivation affect overall health and performance (Harrison and Home 2000).

Employees and their family members should receive a comprehensive education program that addresses issues such as circadian rhythms, shift schedules, and identifying fatigue in co-workers and family members. This education would include information about how individuals and organizations can design strategies to prevent fatigue and alleviate its symptoms and perform positive interventions while on duty Education about dietary, exercise, and sleep requirements and other basic healthy living strategies also is an important component of a comprehensive fatigue program.

The literature and the original study discussed previously demonstrate the importance of including families in implementing fatigue education programs and designing schedules. Shift workers indicated a need for family support in the development and use of personal strategies to ensure a home environment conducive to proper rest and good sleep hygiene. Shift work and fatigue can be difficult for the entire family. A well-designed fatigue training program that includes the family can reduce fatigue-related tension and help ensure a properly rested, productive, and safe work force.

Assisting the Individual Client

An EA professional familiar with the effects of fatigue should be prepared to offer important services to individual clients to help them cope with shift work and fatigue. While a comprehensive education and communication program is the most important tool an EA professional can offer, the following services should also be part of a comprehensive fatigue program:

1. Anger management skills. Disrupted sleep patterns can cause mood decrements that result in anger and irritability Anger management education and counseling would benefit employees' relationships with their significant others and co-workers.

2. Coping strategies. An EA professional can assist employees in the development of personal coping strategies for fatigue and general healthy living.

3. Time management skills. The inability to properly manage personal and professional schedules contributes to overall fatigue.

4. Financial counseling. Financial difficulties cause employees to work overtime and take on second jobs, exacerbating fatigue and relationship problems.

5. Relapse prevention. Fatigue and sleep problems can trigger drug and alcohol relapse, and those in recovery can show chronic sleep abnormalities for months and years. EA professionals can assist in developing personal strategies to cope with sleep problems, fatigue, and shift work during recovery

6. Mental health awareness. Sleep difficulties and insomnia can contribute to depression. EA professionals can raise awareness of mental health and assist employees in receiving appropriate treatment for insomnia, depression, anxiety, and sleep disorders.

7. Family stability. Shift work and fatigue negatively affect family relationships and social life. The EA professional is in a position to raise awareness of these issues, provide information, and make referrals for couples and family counseling where appropriate.

Finally, a comprehensive fatigue management program should encourage the EA professional to use his/her expertise as a change agent. As with other health issues, environmental influences play a very important role in fatigue. Therefore, the culture change principles EA professionals apply to influence the environment surrounding other lifestyle habits would be applicable in a fatigue management program.

Conclusion

Fatigue is a multi-faceted and complex health, social, and organizational issue. It not only affects an individual's health, it is also related to Ask factors and lifestyle habits that EA professionals typically address.

All EA professionals should become familiar with the scientific principles of fatigue and the relationship between fatigue and other lifestyle habits. This knowledge can assist the EA professional in designing programs to effectively address fatigue at both the individual and organizational levels. The EA professional should play a significant role in designing policies and programs to reduce fatigue.

TABLE 1: PARTICIPANT PROFILES

Name      Race              Age          Gender        Operating Area

Dan       White             60           Male          Northern
Mike      White             48           Male          Western
Linda     White             58           Female        Western
Sam       White             44           Male          Southern
Eldon     Black             52           Male          Southern
Ralph     White             53           Male          Northern
John      Hispanic          43           Male          Northern
Tom       White             29           Male          Northern
Mary      White             29           Female        Northern
Gary      White             45           Male          Western
Matt      White             32           Male          Northern

Name      Marital Status    Experience   Assignment

Dan       Married           40 years     Regular
Mike      Married           23 years     Regular
Linda     Married           21 years     Regular
Sam       Divorced          20 years     Regular
Eldon     Married           19 years     Regular
Ralph     Divorced          19 years     Regular
John      Married           10 years     Extra
Tom       Married           8 years      Extra
Mary      Married           4 years      Extra
Gary      Married           3 years      Extra
Matt      Married           1 year       Extra

TABLE 2: ROLES OF THE EA PROFESSIONAL

Supporting Organization    Training              Assisting Individual
                           Organization          Client

Shaping Organizational     Orienting Senior      Anger Management
  Policies                   Leadership

Develop Programs and       Middle Managers and   Drug and Alcohol and
  Procedures                 Shift Work          Relapse Issues
                             Supervisors

Communicate                Employees             Time Management

Foster Positive Cultural   Family Members        Financial Management
  Change                                         Coping Strategies
                                                 Mental Health Issues
                                                 Family Issues

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Denny Holland is director of alertness management in the Health Services Department of Union Pacific Railroad. Joe Luetzinger is director of health promotion in the Health Services Department of Union Pacific. Questions about this report should be directed to Denny Holland at Union Pacific Railroad Company, 1416 Dodge Street, Room 800, Omaha, NE 68179.