In many large cohort studies, the night shift constitutes a risk factor for developing cardiovascular disease and diabetes in workers. Current screening tests for people working in night shift include fasting glycaemia and electrocardiography. In fact, there are few studies focused on the description of the electrocardiographic changes after the night shift. This article describes the protocol of the “ECG modifications induced by the disturbance of the circadian rhythm in night-shift workers (ECGNoct)” study, which was initiated by the National Institute for Infectious Diseases “Prof. Dr. Matei Balș”. Nurses represent the target population.
The protocol includes a full medical and occupational history, lifestyle habits (smoking, alcohol, nutrition), anthropometric and blood pressure measurements, blood tests (fasting glycemia, total cholesterol, triglycerides and high density lipoprotein cholesterol) and electrocardiogram recording. For nurses working in (night) shifts, we will record the electrocardiogram before and soon after the night shift. A cross sectional study will analyze the incidence of the metabolic syndrome criteria, the cardio-metabolic diseases and the electrocardiographic modifications and will compare the results between the group of nurses working and the group of nurse who do not. Based on these results, a longitudinal study will test the hypothesis that night shift increases the risk for cardio-metabolic diseases and that the electrocardiographic modifications precede the clinical symptoms. The results of the study will provide data on the association of night shifts and other non-occupational risk factors with the cardio-metabolic diseases in this specific population of healthcare workers that potentially will integrate into the occupational medicine policies.
If the inline PDF is not rendering correctly, you can download the PDF file here.
1.Eurofound. Working time patterns for sustainable work. Publications Office of the European Union Luxembourg (2018) https://digitalcommons.ilr.cornell.edu/cgi/viewcontent.cgi?article=1635&context=intldownloaded 10.02.2019.
2. Jin J. Screening for Cardiovascular Disease Risk With ECG. JAMA. 2018;319:2346.
3. Otelea MR Streinu-Cercel A Băicus C Nitescu M. The Adipokine Profile and the Cardio-Metabolic Risk in Non-Obese Young Adults. Balkan Med J. 2019;36:155-61.
4. Tsai WC Wu KY Lin GM et al. Clinical Characteristics of Patients Less than Forty Years Old with Coronary Artery Disease in Taiwan: A Cross-Sectional Study. Acta Cardiol Sin.2017;33:233–40.
5. George MG Tong X Bowman BA. Prevalence of Cardiovascular Risk Factors and Strokes in Younger Adults. JAMA Neurol. 2017;74:695–703.
6. Paul Leeson Hypertension and cardiovascular risk in young adult life: insights from CAVI Eur Heart J Suppl. 2017:19 (suppl_B): B24–B29.
7. Mozos I Filimon L. QT and Tpeak-Tend intervals in shift workers. J Electrocardiol. 2013;46:60-5.
8. Cakici M Dogan A Cetin M Suner A Caner A Polat M Kaya H Abus S Akturk E. Negative effects of acute sleep deprivation on left ventricular functions and cardiac repolarization in healthy young adults. Pacing Clin Electrophysiol. 2015;38:713-22.
9. Vetter C Devore EE Wegrzyn LR Massa J Speizer FE Kawachi I Rosner B Stampfer MJ Schernhammer ES. Association Between Rotating Night Shift Work and Risk of Coronary Heart Disease Among Women. JAMA. 2016;315:1726–34.
10. Popa S Moţa M Popa A Moţa E Serafinceanu C Guja C Catrinoiu D Hâncu N Lichiardopol R Bala C Popa A Roman G Radulian G Timar R Mihai B. Prevalence of overweight/obesity abdominal obesity and metabolic syndrome and atypical cardiometabolic phenotypes in the adult Romanian population: PREDATORR study. J Endocrinol Invest. 2016;39:1045-53.
11. Nikpour M Tirgar A Hajiahmadi M Hosseini A Heidari B Ghaffari F Ebadi A Fatemeh Nasiri-Amiri F Firouzbakht M. Shift work and metabolic syndrome: A multi-center cross-sectional study on females of reproductive age. Biomed Rep. 2019;10:311-7.
12. Moreira GC Cipullo JP Ciorlia LA Cesarino CB Vilela-Martin JF. Prevalence of metabolic syndrome: association with risk factors and cardiovascular complications in an urban population. PLoS One. 2014;9:e105056.
13. De Bacquer D De Backer G Kornitzer M Blackburn H. Prognostic value of ECG findings for total cardiovascular disease and coronary heart disease death in men and women. Heart.1998;80:570–7.
14. Yoo GS Kim TW.The Effect of Morningness-Eveningness on Shift Work Nurses: Sleep Quality Depressive Symptoms and Occupational Stress. Sleep Med Res. 2017;8:39-43.
15. Boudreau P Dumont GA Boivin DB. Circadian Adaptation to Night Shift Work Influences Sleep Performance Mood and the Autonomic Modulation of the Heart. PLoS ONE 2013;8: e70813.
16. Krakauer NY Krakauer JC. A new body shape index predicts mortality hazard independently of body mass index. PloS One. 2012;7:e39504.
17. Morikawa Y Miura K Sasaki S Yoshita K Yoneyama S Sakurai M Ishizaki M Kido T Naruse Y Suwazono Y Higashiyama M Nakagawa H. Evaluation of the effects of shift work on nutrient intake: a cross-sectional study. J Occup Health.2008;50:270-8.
18. Barger LK Ogeil RP Drake CL O’Brien CS Ng KT Rajaratnam SM. Validation of a questionnaire to screen for shift work disorder. Sleep.2012;35:1693–1703.
19. European Society of Cradiology.Score risk charts. https://www.escardio.org/Education/Practice-Tools/CVD-prevention-toolbox/SCORE-Risk-Charts,pdf dowloaded 10.02.2019.
20. Prineas R Crow R Blackburn H. The Minnesota Code Manual of Electrocardiographic Findings. 2nd edition London: Springer-Verlag; 2010.
21. Sagie A Larson MG Goldberg RJ Bengtson JR Levy D. An improved method for adjusting the QT interval for heart rate (the Framingham Heart Study). Am J Cardiol. 1992;70:797–801.
22. Surawicz Knilans. CHOU’s electrocardiography in clinical practice. 6th ed Philadelphia: Saunders Elsevier; 2008.
23. Vandenberk B Vandael E Robyns T Vandenberghe J Garweg C Foulon V Ector J Rik Willems R. Which QT Correction Formulae to Use for QT Monitoring? J Am Heart Assoc. 2016;5:e003264.
24. Cheng W-J Cheng Y. Night shift and rotating shift in association with sleep problems burnout and minor mental disorder in male and female employees. Occup Environ Med. 2016;74:483-488.
25. Kazemi R Motamedzade M Golmohammadi R Mokarami H Hemmatjo R Heidarimoghadam R. Field Study of Effects of Night Shifts on Cognitive Performance Salivary Melatonin and Sleep. Saf Health Work. 2018;9:203-9.
26. Asarnow LD Soehner AM Harvey AG. Circadian rhythms and psychiatric illness. Curr Opin Psychiatry. 2013;26:566–71.
27. Nakajima K. Unhealthy eating habits around sleep and sleep duration: To eat or fast? World J Diabetes.2018;9:190–4.
28. Patterson F Grandner MA Malone SK Rizzo A Davey A Edwards DG. Sleep as a Target for Optimized Response to Smoking Cessation Treatment. Nicotine Tob Res. 2019; 21:139–48.
29. Hasler BP Clark DB. Circadian misalignment reward-related brain function and adolescent alcohol involvement. Alcohol Clin Exp Res. 2013;37:558–65.
30. Hasler BP Smith LJ Cousins JC Bootzin RR. Circadian rhythms sleep and substance abuse. Sleep Med Rev. 2012;16:67–81.
31. Cappuccio FP Miller MA. Sleep and Cardio-Metabolic Disease. Curr Cardiol Rep. 2017;19:110.
32. Xi B He D Zhang M Xue J Zhou D. Short sleep duration predicts risk of metabolic syndrome: A systematic review and meta-analysis. Sleep Med Rev.2014;18:293-297.
33. Yeom JH Sim CS Lee J Yun SH Park SJ Yoo C-I Sung JH. Effect of shift work on hypertension: cross sectional study. Ann Occup Environ Med.2017;29:11.
34. Karlsson B Alfredsson L Knutsson A Andersson E Torén K. Total mortality and cause-specific mortality of Swedish shiftand dayworkers in the pulp and paper industry in 1952-2001. Scand J Work Environ Health. 2005;31:30-5.
35. Shan Z Li Y Zong G Guo Y Li J Manson JoAnn Hu FB Willett WC Schernhammer ES Bhupathiraju SN. Rotating night shift work and adherence to unhealthy lifestyle in predicting risk of type 2 diabetes: results from two large US cohorts of female nurses BMJ. 2018; 363:k4641.
36. West AC Smith L David W. Ray DW Loudon ASI Brown TM Bechtold DA. Misalignment with the external light environment drives metabolic and cardiac dysfunction. Nat. Commun. 2017:8:417.
37. Lo SH Lin LY Hwang JS Chang YY Liau CS Wang JD. Working the night shift causes increased vascular stress and delayed recovery in young women. Chronobiol Int. 2010;27:1454–68.
38. Holmes AL Burgess HJ McCulloch K Lamond N Fletcher A Dorrian J Roach G Dawson D. Daytime cardiac autonomic activity during one week of continuous night shift. J Hum Ergol (Tokyo). 2001;30:223-8.
39. Morris CJ Purvis TE Hu K Scheer FA. Circadian misalignment increases cardiovascular disease risk factors in humans. Proc Natl Acad Sci U S A. 2016;113:E1402–E1411.