Distinctive profile of sudden cardiac arrest in middle-aged vs. older adults: a community-based study

Int J Cardiol. 2013 Oct 9;168(4):3495-9. doi: 10.1016/j.ijcard.2013.04.207. Epub 2013 May 17.


Background: While sudden cardiac arrest (SCA) rates increase with age, middle-aged adults (35-59 years) may comprise a significant proportion of SCA cases in the community (30-40%). However, there is a lack of studies evaluating SCA risk factors specifically associated with this age-group of the population.

Methods: Using prospective multiple-source surveillance methodology we identified cases of SCA ≥35 years in the ongoing Oregon Sudden Unexpected Death Study (Portland, Oregon metropolitan area, population≈1,000,000). Out-of-hospital SCA cases, aged 35-59 years were compared to older SCA cases (≥60 years) in a comprehensive analysis of clinical profile of SCA.

Results: The middle-aged (n=753) compared to older (n=1251) cases were more likely to be male, obese, have sleep apnea and seizure disorder (all p≤0.001); and were less likely to have a history of hypertension, diabetes mellitus, known coronary artery disease, congestive heart failure and syncope (all p<0.01). In multivariable analyses the middle-aged group had higher likelihood of male sex (O.R. 1.67, 95% C.I. 1.29-2.18), obesity (2.20, 1.52-3.19), sleep apnea (2.30, 1.44-3.68) and seizure disorder (2.69, 1.64-4.42); and lower rates of known coronary artery disease (0.57, 0.43-0.74) and congestive heart failure (0.35, 0.25-0.48).

Conclusions: SCA in the middle-aged adult was distinguishable from older subjects by higher rates of obesity, sleep apnea and seizure disorder; and lower prevalence of traditional clinical risk markers. With the growing epidemic of obesity, these findings have implications for SCA burden; and suggest the need for a clinical and investigational focus on SCA prediction and prevention in the middle-aged adult, that is distinct from older adults.

Keywords: Community; Coronary artery disease; Middle-age; Obesity; Sudden-death.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Death, Sudden, Cardiac / epidemiology*
  • Female
  • Heart Arrest / diagnosis*
  • Heart Arrest / epidemiology*
  • Heart Arrest / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Population Surveillance* / methods
  • Prospective Studies
  • Residence Characteristics*