gms | German Medical Science

MAINZ//2011: 56. GMDS-Jahrestagung und 6. DGEpi-Jahrestagung

Deutsche Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e. V.
Deutsche Gesellschaft für Epidemiologie e. V.

26. - 29.09.2011 in Mainz

Siesta and risk of coronary artery disease. Results of the Heinz Nixdorf Recall Study

Meeting Abstract

  • Andreas Stang - Universität Halle, Halle
  • Nico Dragano - Department of Medical Sociology, Düsseldorf
  • Charles Poole - University of Chapel Hill, Chapel Hill
  • Susanne Moebus - Universität Duisburg-Essen, Essen
  • Stefan Möhlenkamp - Universität Duisburg-Essen, Essen
  • Axel Schmermund - Cardioangiologisches Centrum Bethanien, Frankfurt
  • Hagen Kälsch - Universität Duisburg-Essen, Essen
  • Raimund Erbel - Universität Duisburg-Essen, Essen
  • Karl-Heinz Jöckel - Universität Duisburg-Essen, Essen

Mainz//2011. 56. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie (gmds), 6. Jahrestagung der Deutschen Gesellschaft für Epidemiologie (DGEpi). Mainz, 26.-29.09.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. Doc11gmds162

DOI: 10.3205/11gmds162, URN: urn:nbn:de:0183-11gmds1628

Published: September 20, 2011

© 2011 Stang et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Background: Several studies have assessed the association between siesta and cardiovascular outcomes and produced conflicting results. This study prospectively examines the association between siesta habits and incidence of coronary artery disease.

Methods: The baseline examination of 4,487 participants without overt coronary heart disease aged 45-75 years included interviews, physical examination, laboratory tests, and electron beam computed tomography. We studied the influence of siesta habits on risk of coronary artery disease during a median follow-up of 7.2 years. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (95%CI). We identified a minimally sufficient adjustment set by a directed acyclic graph. The adjustment set included current smoking, history of diabetes mellitus, regular difficulties falling asleep, age, systolic and diastolic blood pressure, BMI, waist circumference, coronary calcium score, CRP, LDL and HDL cholesterol, ankle-brachial index, and sleep duration at night. We excluded 334 subjects because of missing data on any of the covariates at baseline.

Results: Out of 1,966 and 2,187 men and women, 86 men and 35 women suffered nonfatal acute myocardial infarction or coronary death (crude rate: men: 6.2 per 1,000 person-years; women: 2.2 per 1,000 person-years). Only subjects who took regular long (>60 min per day; n=105, 2.5%) siesta compared to subjects who did not take siesta or took siesta only irregularly (reference group) had a higher event rate (men: crude HR=3.6, 95%CI: 1.7-7.4; adjusted HR=2.3, 95%CI: 1.1-5.0; women: crude HR=5.7, 95%CI: 1.7-18.8; adjusted HR=4.0, 95%CI: 1.2-13.8). Several sensitivity analyses did not substantially change these findings.

Conclusions: We found an increased hazard ratio for acute myocardial infarctions and cardiac death among men and women who took regular long siestas in a Non-Mediterranean Northern European population of people aged 45-75 years although we adjusted for several confounders including measures of subclinical atherosclerosis (coronary calcium score and ankle-arm index). Data from 24-h ambulatory monitoring suggest that blood pressure during siesta decreases to similar levels as at night. After siesta, blood pressure rapidly rises similarly as after night sleep that could be associated with sympathetic nervous activation and CVD risk. In addition, acute changes in posture in the morning have prothrombotic effects that could also occur after daytime napping and may trigger thrombotic cardiovascular events.