Shift Work Type

Population data indicate that 14–28% of workers are involved in a shift work schedule which includes some time spent working at night. Shift workers predominate in heavy industries and emergency services, but they are also increasingly found in finance, ‘E-commerce,’ and service industries. Shift work-related sleep disorder is characterized by excessive sleepiness at work and insomnia during scheduled times for sleep. Data from epidemiological studies also suggest that shift workers, and especially those engaged in night work, are generally more prone to gastro-intestinal problems, obesity, heart disease, and cancer than day workers. Disruption of circadian rhythms during shift work is thought to be important in explaining these increased health problems. Nevertheless, differences between shift workers and day workers in lifestyle factors, including participation in physical activity, have been generally under-researched. Evaluated treatments for shift work-related sleep problems include light exposure, melatonin ingestion, hypnotics, caffeine, and central nervous stimulants or other agents influencing sleepiness. Most studies show positive results, although most have involved a simulation of shift work in the laboratory rather than actual shift work which is associated with a multitude of biological and socio-behavioral stressors. Modafinil and armodafinil are two of the few substances which have been studied in randomized controlled trials involving patients with diagnosed shift work sleep disorder. Both substances were found to improve sleepiness during the work period and sleep quality in rest periods. It seems as though there are no randomized controlled trials which have tested the efficacy of lifestyle-based interventions on such outcomes in patients with diagnosed shift work type sleep disorder.