Gender differences in cardiovascular mortality by C-reactive protein level in the United States: evidence from the National Health and Nutrition Examination Survey III.

BACKGROUND: The association between C-reactive protein (CRP) and cardiovascular (CV) mortality by gender has not been previously described using a data set that is representative of the US population.
METHODS: We used Cox proportional hazards models to explore gender differences in CRP-associated mortality via the National Health and Nutrition Examination Survey III 1988-1994 linked to the National Death Index with mortality follow-up through 2006. We examined CV mortality as well as all-cause mortality hazards.
RESULTS: The final sample size included a total of 13,878 individuals (7,364 women and 6,514 men) with a median follow up of 18.2 years. All models controlled for race, age, smoking, high-density lipoprotein, hypertension, diabetes mellitus, waist circumference, and total cholesterol. Men with a CRP >3.0 mg/L relative to those with a CRP ≤3.0 mg/L had elevated CV mortality hazards (hazard ratio [HR] 1.79, 95% CI 1.23-2.60) and all-cause mortality hazards (HR 1.57, 95% CI 1.29-1.90). In women, elevated CRP was not significantly associated with either increased CV (HR 1.20, 95% CI 0.90-1.59) or all-cause mortality hazards (HR 1.09, CI 0.93-1.29).
CONCLUSION: National guidelines from various agencies that make recommendations on the diagnostic and prognostic use of CRP have treated men and women equally. We find that there may be reason to tailor recommendations based upon one's gender.