Endocrine Abstracts

Objectives: The present aimed to investigate the circadian pattern of salivary cortisol & sulfatoxy melatonin level in night shift professionals and actual day workers & to find out these changes in the circadian pattern produce by night shift are reversible in due course of time.

Methods: 56 Nursing professionals of both gender who perform day and night shifts and 56 actual controls were also recruited in this study. Saliva and urine samples were collected at ~8 h interval in their night shift and day shift schedule and in the control subjects. Groups were compared by applying paired and unpaired t test.

Result: Significant difference was found in night cortisol levels among night (4.08±3.28) vs day shift (2.62±2.37), (P<0.005), while in controls (1.82±1.18) (P<0.0005) when compared to night shift. Alteration in mean morning cortisol level was also found between night (3.88±2.54) vs day shift (54.79±2.46) (P<0.05), while in controls (5.71±3.55) P<0.005 when compared to night shift. Night melatonin level was found declined as compared to morning level and this pattern was significant when compared night melatonin between night (17.65±12.20) vs day shift (22.41±13.70), while in controls (25.45±17.20) (P<0.05) when compared to night shift. morning melatonin level between night (21.08±14.50) vs day shifts (27.36±14.46) (P<0.05), while in controls (28.91±16.20) (P<0.05) when compared to night shift. Difference was insignificant when cortisol and melatonin levels found in night shift were compare to actual controls and it elucidates the circadian pattern was recovered in day shift.

Conclusion: Alterations in circadian pattern of salivary cortisol and melatonin sulfate were found during night shift due to internal desynchronization. Sleep loss might be associated with decreased melatonin level leads to endocrinal and cardiovascular diseases.