Is there an association between socioeconomic status and the degree of diurnal variation in heart rate?

Benjamin P van Nieuwenhuizen; Paul de Goede; Hanno L Tan; Bert-Jan van den Born; Anton Kunst

doi:10.1016/j.ijcrp.2021.200118

Is there an association between socioeconomic status and the degree of diurnal variation in heart rate?

Int J Cardiol Cardiovasc Risk Prev. 2021 Nov 27:11:200118. doi: 10.1016/j.ijcrp.2021.200118. eCollection 2021 Dec.

Authors

Benjamin P van Nieuwenhuizen¹, Paul de Goede^{2

3}, Hanno L Tan^{4

5}, Bert-Jan van den Born^{1

6}, Anton Kunst¹

Affiliations

¹ Department of Public and Occupational Health, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.
² Laboratory of Endocrinology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam Gastroenterology, Endocrinology, and Metabolism, Amsterdam, the Netherlands.
³ Hypothalamic Integration Mechanisms Group, Netherlands Institute for Neuroscience (NIN), An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands.
⁴ Department of Clinical and Experimental Cardiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.
⁵ Netherlands Heart Institute, Utrecht, the Netherlands.
⁶ Department of Vascular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands.

Abstract

Background: Disruption in circadian rhythms is associated with cardiovascular disease and may play a role in socioeconomic differences in cardiovascular disease prevalence. However, it is unclear whether low SES is associated with a lower diurnal rhythm in autonomic activity markers. We investigated the association between SES and the amplitude of the daily fluctuation of heart rate.

Methods: We included data of 450 participants of a HELIUS sub-study in Amsterdam, the Netherlands. Participants wore an Actiheart monitor (CamNtech), a chest-worn monitor which measures heart rate every 15 s for several days. Cosinor analysis was performed on the time series of heart rate within each participant. We analyzed the association between the cosinor parameters (amplitude, midline and peak time of the diurnal HR rhythm) and SES indicators (education, occupational class and a proxy of income) in multivariate linear regression models, adjusting for age, sex and ethnicity.

Results: There was a clear diurnal rhythm in the average heart rates, with a peak between noon and 18:00 and a trough between 04:00 and 06:00. This rhythm was present for all categories of education, occupation and income proxy. The estimates for the cosinor parameters did not differ consistently and significantly between categories of education, occupation or income proxy.

Conclusions: We did not find any consistent evidence to support our hypothesis of a diminished amplitude in the diurnal variation of heart rate in individuals with lower SES. Future studies should explore SES differences in the diurnal variation in markers of autonomic activity other than heart rate.

Keywords: Autonomic nervous system; BRS, baroreflex sensitivity; CVD, cardiovascular disease; Circadian; Diurnal; HELIUS, Healthy life in an urban setting study; HRV, heart rate variability; Heart rate; SES, socioeconomic status; Socioeconomic status.