Time of exposure to night work and carotid atherosclerosis: a structural equation modeling approach using baseline data from ELSA-Brasil
- 141 Downloads
The study of cardiovascular diseases (CVD) associated with night work is difficult due to the long period required for conditions to manifest and the healthy-worker effect. Analyzing asymptomatic pre-clinical changes in the atherosclerotic process is a way to assess the pathways between exposure to night work and CVD.
To evaluate the associations between night work and subclinical atherosclerosis measured by carotid intima-media thickness (CIMT) using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).
We conducted cross-sectional analyses using baseline data (2008–2010) from 9785 civil servants, aged 35–74 years. The associations between time of exposure to night work and mean CIMT were examined using a structural equation model.
The sample included 4259 men and 5526 women, mean age of 51.6 years. A total of 1778 (18.2%) individuals were exposed to night work (594 current and 1184 former night workers), and the mean years of night work exposed was 11.47 (SD = 9.45) years. On average, mean CIMT was 0.606 (SD = 0.130) mm. Among men, the increase in exposure to night work was significantly associated with an increase in BMI and CIMT. Among women, night work was not associated with increased CIMT. In relation to the indirect associations, results suggest a possible mediation by BMI, diabetes and hypertension on the association between the years of night work and mean CIMT only among men.
Night work was associated with increased CIMT only among men. These findings add to the knowledge of the possible pathways that link night work and carotid atherosclerosis. Additionally, these results contribute to the recognition of work schedules as a public health problem that should be addressed by the medical community and policy makers.
KeywordsCarotid intima-media thickness Atherosclerosis Work schedule Night shift work
The ELSA-Brasil baseline was supported by the Brazilian Ministry of Health (Science and Technology Department) and the Brazilian Ministry of Science and Technology (Financiadora de Estudos e Projetos and CNPq National Research Council) [Grants 01 06 0010.00 RS, 0106 0212.00 BA, 01 06 0300.00 ES, 01 06 0278.00 MG, 01 06 0115.00 SP, 01 06 0071.00 RJ]. ASC was the recipient of scholarships from CNPq-Brasil (150551/2015-0).
Compliance with ethical standards
Conflict of interest
All authors declare that they do not have any competing interests.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
- Bentzon JF, Otsuka F, Virmani R, Falk E (2014) Mechanisms of plaque formation and rupture.Circ Res.114(12):1852–1866. https://doi.org/10.1161/CIRCRESAHA.114.302721
- Fedeli LG, Vidigal PG, Leite CM, Castilhos CD, Pimentel RA et al (2013) Logistics of collection and transportation of biological samples and the organization of the central laboratory in the ELSA- Brasil. Rev SaudePublica 47(2):63–71. https://doi.org/10.1590/S0034-8910.2013047003807 CrossRefGoogle Scholar
- Folsom AR, Kronmal RA, Detrano RC, O’Leary DH, Bild DE et al (2008) Coronary artery calcification compared with carotid intima-media thickness in the predictionof cardiovascular disease incidence: the Multi-Ethnic Study of Atherosclerosis (MESA). Arch Intern Med 168(12):1333–1339CrossRefGoogle Scholar
- Gepner AD, Young R, Delaney JA, Tattersall MC, Blaha MJ, Post WS, Stein JH (2015) A comparison of coronary artery calcium presence, carotid plaque presence, and carotid intima-media thickness for cardiovascular disease prediction in the multi-ethnic study of atherosclerosis (MESA). Circ Cardiovasc Imaging 8(1):e002262. https://doi.org/10.1161/CIRCIMAGING.114.002262 CrossRefGoogle Scholar
- Haupt CM, Alte D, Dörr M, Robinson DM, Felix SB et al (2008) The relation of exposure to shift work with atherosclerosis and myocardial infarction in a general population. Atherosclerosis 201(1):205–211. https://doi.org/10.1016/j.atherosclerosis.2007.12.059 CrossRefGoogle Scholar
- MacCallum RC, Browne MW, Sugawara HM (1996) Power analysis and determination of sample size for covariance structure modeling. Psychol Methods 130–149Google Scholar
- Mita T, Katakami N, Shiraiwa T, Yoshii H, Onuma T et al (2016) Sitagliptin attenuates the progression of carotid intima-media thickening in insulin-treated patients with type 2 diabetes: the sitagliptin preventive study of intima-media thickness evaluation (spike): randomized controlled trial. Diabetes Care 39(3):455–464. https://doi.org/10.2337/dc15-2145 CrossRefGoogle Scholar
- Puttonen S, Kivimäki M, Elovainio M, Pulkki-Råback L, Hintsanen M et al (2009) Shift work in young adults and carotid artery intima-media thickness: The Cardiovascular Risk in Young Finns study. Atherosclerosis 205(2):608–613. https://doi.org/10.1016/j.atherosclerosis.2009.01.016 CrossRefGoogle Scholar
- Santos IS, Bittencourt MS, Goulart AC, Schmidt MI, Diniz MFHS. et al. (2017) Insulin resistance is associated with carotid intima-media thickness in non-diabetic subjects. A cross-sectional analysis of the ELSA-Brasil cohort baseline. Atherosclerosis 260:34–40. https://doi.org/10.1016/j.atherosclerosis.2017.03.011 CrossRefGoogle Scholar
- Santos IS, Alencar AP, Rundek T, Goulart AC, Barreto SM, Pereira AC, Benseñor IM, Lotufo PA. Low impact of traditional risk factors on carotid intima-media thickness: the ELSA-Brasil cohort. Arterioscler Thromb Vasc Biol 35(9):2054–2059. https://doi.org/10.1161/ATVBAHA.115.305765
- Silva-Costa A, Rotenberg L, Nobre AA, Schmidt MI, Chor D, Griep RH (2015) Gender-specific association between nightwork exposure and type 2 diabetes: results from the longitudinal study of adult health, ELSA-Brasil. Scand J Work Environ Health 41(6):569–578. https://doi.org/10.5271/sjweh.3520 CrossRefGoogle Scholar
- Stein JH, Korcarz CE, Hurst RT, Lonn E, Kendall CB et al (2008) Use of carotid ultrasound to identify subclinical vascular disease and evaluate cardiovascular disease risk: a consensus statement from the American Society of Echocardiography carotid intima-media thickness task force endorsed by theSociety for Vascular Medicine. J Am SocEchocardiogr 21:93e111Google Scholar