JOURNAL ARTICLE

The association between white blood cell count and acute myocardial infarction in-hospital mortality: findings from the National Registry of Myocardial Infarction

Mary Grzybowski, Robert D Welch, Lori Parsons, Chiadi E Ndumele, Edmond Chen, Robert Zalenski, Hal V Barron
Academic Emergency Medicine 2004, 11 (10): 1049-60
15466147

OBJECTIVES: Although cross-sectional and prospective studies have shown that the white blood cell (WBC) count is associated with long-term mortality for patients with ischemic heart disease, the role of the WBC count as an independent predictor of short-term mortality in patients with acute myocardial infarction (AMI) has not been examined as extensively. The objective of this study was to determine whether the WBC count is associated with in-hospital mortality for patients with ischemic heart disease after controlling for potential confounders.

METHODS: From July 31, 2000, to July 31, 2001, the National Registry of Myocardial Infarction 4 enrolled 186,727 AMI patients. A total of 115,273 patients were included in the analysis.

RESULTS: WBC counts were subdivided into intervals of 1,000/mL, and in-hospital mortality rates were determined for each interval. The distribution revealed a J-shaped curve. Patients with WBC counts >5,000/mL were subdivided into quartiles, whereas patients with WBC counts <5,000/mL were assigned to a separate category labeled "subquartile" and were analyzed separately. A linear increase in in-hospital mortality by WBC count quartile was found. The unadjusted odds ratio (OR) for the fourth versus the first quartile showed strong associations with in-hospital mortality among the entire population and by gender: 4.09 (95% confidence interval [95% CI] = 3.83 to 4.73) for all patients, 4.31 (95% CI = 3.93 to 4.73) for men, and 3.65 (95% CI = 3.32 to 4.01) for women. Following adjustment for covariates, the magnitude of the ORs attenuated, but the ORs remained highly significant (OR, 2.71 [95% CI = 2.53 to 2.90] for all patients; OR, 2.87 [95% CI = 2.59 to 3.19] for men; OR, 2.61 [95% CI = 2.36 to 2.99] for women). Reperfused patients had consistently lower in-hospital mortality rates for all patients and by gender (p < 0.0001).

CONCLUSIONS: The WBC count is an independent predictor of in-hospital AMI mortality and may be useful in assessing the prognosis of AMI in conjunction with other early risk-stratification factors. Whether elevated WBC count is a marker of the inflammatory process or is a direct risk factor for AMI remains unclear. Given the simplicity and availability of the WBC count, the authors conclude that the WBC count should be used in conjunction with other ancillary tests to assess the prognosis of a patient with AMI.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read
15466147
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"