January 17, 2007
Nearly 40% of US workers experience fatigue, a problem that carries billions of dollars in costs from lost productivity, according to a study in the January Journal of Occupational and Environmental Medicine, the official publication of the American College of Occupational and Environmental Medicine (ACOEM).

Led by Judith A. Ricci, ScD, MS, of Caremark, Hunt Valley, Md, the researchers analyzed data from a nationwide study of the relationship between health and productivity at work. Of the nearly 29,000 employed adults interviewed, 38% said they had experienced “low levels of energy, poor sleep, or a feeling of fatigue” during the past 2 weeks. With adjustment for other factors, fatigue was more common in women than men, in workers less than 50 years old, and in white workers compared with African-Americans. Workers with high-control jobs—relatively well-paid jobs with decision-making responsibility—also reported higher rates of fatigue.

The study looked at the effects of fatigue on health-related lost productive time: not just absenteeism but also “presenteeism,” or days the employee was at work but performing at less than full capacity because of health reasons. Nine percent of workers with fatigue reported lost productive work time. Fatigue reduced work performance mainly by interfering with concentration and increasing the time needed to accomplish tasks.

The rate of lost productivity for all health-related reasons was also much higher for workers with fatigue: 66%, compared with 26% for workers without fatigue. Total lost productive time averaged 5.6 hours per week for workers with fatigue, compared to 3.3 hours for their counterparts without fatigue. For US employers, fatigue carried overall estimated costs of more than $136 billion per year in health-related lost productivity—$101 billion more than for workers without fatigue. Eighty-four percent of the costs were related to reduced performance while at work, rather than absences.

Health conditions for which fatigue is a major symptom—such as depression or anxiety—accounted for only a small part of the productivity losses. Far more of the costs were thought to result from a wide range of other physical and mental health problems that may occur when fatigue is also present.