C-Reactive Protein, the Metabolic Syndrome, and Risk of Incident Cardiovascular Events

TLDR

The metabolic syndrome is defined by having three or more of upper‑body obesity, hypertriglyceridemia, low HDL, hypertension, or abnormal glucose, and represents a high‑risk population. This study aimed to examine how C‑reactive protein (CRP) relates to the metabolic syndrome and predicts incident cardiovascular events in a large cohort of healthy women. Researchers followed 14,719 women for eight years, measuring CRP levels and metabolic syndrome components, and tracked myocardial infarction, stroke, revascularization, or cardiovascular death to assess event‑free survival. Higher CRP levels correlated with more metabolic syndrome traits, and CRP added prognostic value beyond the syndrome itself, with event rates 3.4 versus 5.9 per 1000 person‑years in those with and without elevated CRP, indicating that CRP measurement provides clinically important risk information.

Abstract

The metabolic syndrome describes a high-risk population having 3 or more of the following clinical characteristics: upper-body obesity, hypertriglyceridemia, low HDL, hypertension, and abnormal glucose. All of these attributes, however, are associated with increased levels of C-reactive protein (CRP).We evaluated interrelationships between CRP, the metabolic syndrome, and incident cardiovascular events among 14 719 apparently healthy women who were followed up for an 8-year period for myocardial infarction, stroke, coronary revascularization, or cardiovascular death; 24% of the cohort had the metabolic syndrome at study entry. At baseline, median CRP levels for those with 0, 1, 2, 3, 4, or 5 characteristics of the metabolic syndrome were 0.68, 1.09, 1.93, 3.01, 3.88, and 5.75 mg/L, respectively (P(trend) <0.0001). Over the 8-year follow-up, cardiovascular event-free survival rates based on CRP levels above or below 3.0 mg/L were similar to survival rates based on having 3 or more characteristics of the metabolic syndrome. At all levels of severity of the metabolic syndrome, however, CRP added prognostic information on subsequent risk. For example, among those with the metabolic syndrome at study entry, age-adjusted incidence rates of future cardiovascular events were 3.4 and 5.9 per 1000 person-years of exposure for those with baseline CRP levels less than or greater than 3.0 mg/L, respectively. Additive effects for CRP were also observed for those with 4 or 5 characteristics of the metabolic syndrome. The use of different definitions of the metabolic syndrome had minimal impact on these findings.These prospective data suggest that measurement of CRP adds clinically important prognostic information to the metabolic syndrome.