Obesity paradox or hypoxia preconditioning: How obstructive sleep apnea modifies the Obesity-MI relationship

Sleep Med. 2023 Oct:110:132-136. doi: 10.1016/j.sleep.2023.07.035. Epub 2023 Aug 2.

Abstract

Objectives: The objective of this study was to evaluate the interaction between obesity and obstructive sleep apnea on acute MI in hospital mortality.

Methods: This retrospective cohort study utilized Veterans Health Administration data from years 1999-2020. Participants were categorized according to their body mass index (BMI) to non-obese (BMI <30) and obese (BMI ≥30) groups. Clinical obstructive sleep apnea (SA) diagnosis was confirmed using ICD9/10 codes and the study subgroups included non-obese with no obstructive sleep apnea (nOB-nSA), non-Obese with obstructive sleep apnea (nOB-SA), obese with no obstructive sleep apnea (OB-nSA), and obese with obstructive sleep apnea (OB-SA). The primary outcome was odds ratio of in-hospital mortality during the hospitalization with acute MI as the principal diagnosis adjusted for age, gender, race, ethnicity, and Charlson comorbidity index (CCI) with the nOB-nSA group as the comparison group.

Results: Among 72,036 veterans with acute-MI hospitalization, individuals with obesity and obstructive sleep apnea (OB-SA) had the lowest in-hospital mortality rate (1.0%) compared to those without obesity and obstructive sleep apnea (nOB-nSA, 2.8%), with obesity but without obstructive sleep apnea (OB-nSA, 2.4%), and with obesity and obstructive sleep apnea (nOB-SA, 1.4%). The adjusted odds ratio for mortality, compared to nOB-nSA, was 9% higher but not significant in OB-nSA (aOR, 1.09, 95%CI: 0.95, 1.25), 46% lower in OB-nSA (aOR, 0.54, 95%CI: 0.45, 0.66), and 52% lower in OB-SA (aOR, 0.48: 95%CI: 0.41, 0.57).

Conclusion: Our data suggest that the association between obesity and improved survival in acute MI is largely driven by the presence of sleep apnea.

Keywords: Hypoxic preconditioning; Intermitted hypoxia; Obesity paradox; Survival.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Mass Index
  • Humans
  • Hypoxia
  • Myocardial Infarction*
  • Obesity / complications
  • Obesity Paradox
  • Retrospective Studies
  • Sleep Apnea Syndromes*
  • Sleep Apnea, Obstructive*