Original Research Article
Year: 2014 | Month: February | Volume: 4 | Issue: 2 | Pages: 46-52
Altered Circadian Secretion of Salivary Cortisol during Night Shift
Anjum B1,2*, Verma N S2**, Tiwari S3***, Fatima Gy1*, Naz Q2#, Bhardwaj S2*, Singh P2#, Mishra S2#, Singh R1##, Mahdi A A1$
*SRF,**Professor, ***Associate Professor, #PhD Student & SRF, ##Assistant Professor, $Professor & Head
1Departments of Biochemistry, 2Departments of Physiology, 3Departments of Surgery,
King George’s Medical University-226003, India.
Corresponding Author: Narsingh Verma
ABSTRACT
Background: Rotating night shift disrupts the circadian rhythms and has been associated with physiological stress, general fatigue, sleep disturbances and cardiovascular diseases. Alterations in the sleep pattern leads to increased cortisol and decreased melatonin which might be associated physiological stress and cardiovascular diseases.
Objectives: The objective of the present study was to investigate circadian secretion of salivary cortisol in rotating night shift nursing professionals.
Methods: 62 healthy nursing professionals of both genders performing day and night shifts duties were recruited. Each study subject had a monthly scheduled of regular 9 night shifts (12 hours night shift, from 20:00 to 08:00) followed by remaining 17-18 day shifts (6 hours day shift, from 08:00 to 14:00) with a total of 4 days off in between. Saliva samples were collected at around 8 hours interval while they were performing night duties and repeated when they were assigned day duties. Salivary cortisol level was estimated by the ELISA (Competitive) method.
Results: Significant difference was found in night cortisol among night (4.34 ± 3.37) vs day shift (2.70 ± 2.32), (p<0.001). Alteration in morning cortisol was also found between night (3.73 ± 2.47) vs day shift (5.00 ± 2.73). The circadian pattern of cortisol was altered by rotating night shift particularly at night and in the morning time.
Conclusion: The present study concluded that the desynchronization was appeared during night shift and entrainment of circadian rhythm was occurred in day shift.
Key words: Rotating night shift; circadian rhythm; salivary cortisol.