Improving Sleep Quality for Women Who Work Night Shifts : A Pilot Study of a Sleep Hygiene Intervention

Background: Sleep is a modifiable risk factor increasingly linked with cancer incidence. Disrupted sleep patterns and circadian rhythms may increase the risk of developing breast cancer in female night shift workers. This pilot study examined the impact of a sleep hygiene intervention on the sleep quality (SQ) and quality of life (QOL) in women who work night shifts. Methods: A single arm, sleep hygiene intervention was delivered by telephone to a convenience sample of 47 female shift workers (mean age=47yrs) on rotating or permanent night shifts at least 3 times per month for at least 2 years. The program was adapted from a hospital sleep clinic protocol based on cognitive behaviour therapy (CBT) principles. Women received 10 sessions and 2 booster sessions over a 40-week period. SQ was assessed at baseline, 6- and 12-months using the Pittsburgh Sleep Quality Index, a Sleep Diary, and Actigraph readings. QOL was measured by the Quality of Life Enjoyment and Satisfaction Questionnaire. Changes in SQ were examined according to chronotype (morning-type, evening-type, neither-type). Results: SQ improved significantly over the period of the study, with good sleep reported by 21%, 46% and 51% of participants at baseline, 6 months and 12 months, respectively. Consistency was seen across the different SQ measures. The intervention had significant positive effects for all chronotypes, but was more effective for both morning-types and neither-types than for evening-types. Women’s sense of well-being improved after 6 months (p=.01) and was maintained at one year. Conclusion: The CBT-based sleep hygiene intervention led to improvements in sleep quality at 6 months that were maintained at one year. Interventions to improve sleep quality for women shift workers offer a novel approach with the potential to reduce breast cancer risk.Medicine, Faculty ofNon UBCPopulation and Public Health (SPPH), School ofUnreviewedFacultyResearche