Relative elevation in baseline leukocyte count predicts first cerebral infarction

Neurology. 2005 Jun 28;64(12):2121-5. doi: 10.1212/01.WNL.0000165989.12122.49.


Background: Atherosclerosis is an inflammatory disease, and leukocyte levels are associated with future risk of ischemic cardiac disease.

Objective: To investigate the hypothesis that relative elevations in leukocyte count in a stroke-free population predict future ischemic stroke (IS).

Methods: A population-based prospective cohort study was performed in a multiethnic urban population. Stroke-free community participants were identified by random-digit dialing. Leukocyte levels were measured at enrollment, and participants were followed annually for IS, myocardial infarction (MI), and cause-specific mortality. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% CIs for IS, MI, and vascular death after adjustment for medical, behavioral, and socioeconomic factors.

Results: Among 3,103 stroke-free community participants (mean age 69.2 +/- 10.3 years) with baseline leukocyte levels measured, median follow-up was 5.2 years. After adjusting for stroke risk factors, each SD in leukocyte count (1.8 x 10(9) cells/L) was associated with an increased risk of IS (HR 1.22, 95% CI 1.05 to 1.42), and IS, MI, or vascular death (HR 1.13, 95% CI 1.02 to 1.26). Compared with those in the lowest quartile of leukocyte count, those in the highest had an increased risk of IS (adjusted HR 1.75, 95% CI 1.08 to 2.82). The effect on atherosclerotic and cardioembolic stroke was greater than in other stroke subtypes.

Conclusion: Relative elevations in leukocyte count are independently associated with an increased risk of future ischemic stroke and other cardiovascular events.

Publication types

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

MeSH terms

  • Aged
  • Atherosclerosis / blood*
  • Atherosclerosis / complications*
  • Atherosclerosis / diagnosis
  • Brain Ischemia / blood*
  • Brain Ischemia / diagnosis*
  • Brain Ischemia / etiology
  • Cerebral Infarction / blood*
  • Cerebral Infarction / diagnosis*
  • Cerebral Infarction / etiology
  • Cohort Studies
  • Embolism / blood
  • Embolism / complications
  • Embolism / diagnosis
  • Humans
  • Inflammation / blood
  • Inflammation / complications
  • Inflammation / diagnosis
  • Leukocyte Count / statistics & numerical data
  • Leukocytes / immunology
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prospective Studies
  • Risk Factors
  • Up-Regulation / immunology