24 HOURS CHRONOMICS OF AMBULATORY BLOOD PRESSURE/HEART RATE IN TERMS OF ACROPHASE & HYPERBARIC INDEX IN NIGHT SHIFT NURSING PROFESSIONALS: RISK FOR CARDIOVASCULAR DISEASES

Objective: This study was aimed to investigate the effect of Light at night and Rotating night shift as risk factor for cardiovascular diseases. 24 hours chronomics of BP/HR in terms of Double amplitude, Acrophase and Hyperbaric index and its relation with circadian rhythm of salivary cortisol and 6 sulfatoxy melatonin levels in night shift nursing professional. Design and method: 56 night shift nurses, aged 20 to 40 years, performing day and night shift duties were recruited from the Trauma Center, KGMU, India, and 56 age sex matched actual day workers were also enrolled as controls. During their night and day shift duties, BP/HR were recorded by Ambulatory Blood Pressure Monitoring (ABPM) along with circadian pattern of cortisol in saliva, metalonin in urine also tested. Results: Highly significant difference was found in double amplitude (2DA) of among between night (23.10 ± 14.68) and day shift (34.27 ± 16.44) (p < 0.0005). In night shift, hyperbaric index (HBI) of mean SBP was found to be increased at 00 to 03 am (midnight) while during day shift, peak was found at 06 to 09 am. HBI of mean HR was found to be increased at 18 to 21 pm during night shift while in controls, peak was found at 09 to 12 & again 15 to 18 pm of SBP, DBP & HR. Alterations in Acrophase of BP/HR were very common among night shift workers and Ecphasia was found in few nights shift workers. Difference was found in night cortisol levels among night (4.08 ± 3.28) vs day shift (2.62 ± 2.37), while in comparison to night shift or day shift with controls (1.82 ± 1.18) these difference was significant (p < 0.05). Conclusions: Alteration in morning melatonin and Night cortisol level were found during night shift. Reverse pattern of Acrophase and HBI of BP/HR along with salivary cortisol during night shift represents desynchronization. It indicates that the circadian rhythm was disrupted during night shift and incomplete recovery occurs during day shift. It may leads to future cardio vascular diseases risk.