Night shift work and long working hours are associated with an increased risk of some chronic diseases like cardiovascular, endocrine, digestive diseases and others. The aim of the study was to follow the impact of night shift work and long working hours on health of Bulgarian physicians.
A cross-sectional anonymous survey, comprising 761 physicians of age 44.3±14.1 years, and including information on work place variables, working hours and shift system was carried. The health status questionnaire included a list of 13 groups of diseases diagnosed by a physician. Statistical analyses were carried out with SPSS.
63.7% of the physicians worked rotating shifts, mainly 12- hour shifts (49.7%) and 67.5% had a history of night work. Overtime and multiple work places were common, contributing to long working hours/week with 38.5% working 41–50 hours/week, 27.8% - 51–60 hours/week and 13.7% - >61 hours/week. Results showed that the highest rate of cardiovascular diseases was in ex night shift workers both for males (F=18.728, p<0.01) and for females (F=9.940, p<0.01). The rate of cardiovascular, endocrine, digestive diseases was the highest in physicians who worked 51-60 or >61 hours/week, except for the rate of cardiovascular diseases in female physicians, the highest in those working 20-40 hours/week. Work schedule was a predictor of cardiovascular diseases and mental disorders; history of night work was a predictor of digestive diseases.
Our data contribute to the evidence that night shift work and long working hours increase health risk.
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