Relationship between the metabolic syndrome and C-reactive protein with stroke prevalence

Purpose: Identify any relationship between metabolic syndrome and CRP concentrations with stroke prevalence.

Methods: Subjects > 19 years old completing the 2009-10 National Health and Nutrition Examination Survey (NHANES), a nationally representative, complex sample combining interviews and physical examinations, were included. Metabolic syndrome was defined as having at least 3 of the following: hypertension, insulin resistance, hypertriglyceridemia, low HDL cholesterol, or high waist circumference. Elevated CRP was defined as > 2 mg/L. Multivariate logistic regression modeling accounting for clustering and unequal probability of selection in complex samples was used to assess the relationship between CRP and metabolic syndrome with stroke prevalence. Potential interaction between CRP and metabolic syndrome was also statistically assessed.

Results: A total of 6210 subjects met the inclusion criteria and were included in the analysis. Two-thirds of subjects were 20-55 years old, 52% were female, and the overall stroke prevalence was 2.6%. Metabolic syndrome prevalence was 29% overall, 21% in subjects 20-55 years old, and 46% in subjects >55 years old. Stroke prevalence in those without metabolic syndrome was 1.3% (% population attributable risk = 50%). Multivariate logistic regression modeling revealed a significant association between stroke prevalence and advanced age (OR 2.1 [1.0-4.3]), African-American race (OR 2.6 [1.2-5.7]), and metabolic syndrome (OR 3.6 [1.5-8.3]). Smoking (OR 0.92 [0.46-1.8]) or elevated CRP levels (OR 1.8 [0.35-9.1]) were not associated with stroke prevalence. No evidence of interaction was found between CRP levels and metabolic syndrome.

Conclusion: Age >55 years, African-American race, and the metabolic syndrome were the most powerful predictors of stroke prevalence. Although elevated CRP has previously been shown to be associated with stroke prevalence, we did not find an association between CRP and stroke prevalence when controlling for other risk factors.