Tracking of high-sensitivity c-reactive protein after an initially elevated concentration: the jupiter study

ating Rosuvastatin) trial suggests that increased high-sensitivity C-reactive protein (hsCRP) concentrations may be useful in decisions about the initiation of statin therapy for primary prevention of vascular disease. Al-though studies of specific populations have suggested that hsCRP is a reliable longitudinal marker, it is un-clear how strongly hsCRP tracks in individuals after a single increased concentration. METHODS: We evaluated tracking of hsCRP in 8901 in-dividuals randomized to placebo in the JUPITER trial. These individuals had screening LDL cholesterol con-centrations130 mg/dL (3.37 mmol/L) and hsCRP concentrations 2 mg/L, with subsequent hsCRP measurements made before randomization; at 13 weeks; 1, 2, 3, and 4 years later; and at trial termination. Longitudinal trends and associations were evaluated nonparametrically with box plots and Spearman corre-lations. After data transformation to achieve normal-ity, repeated-measures regression models estimated the intraclass correlation of hsCRP, with and without controlling for known demographic, lifestyle, and medical determinants of hsCRP concentration. For comparison, we evaluated tracking of systolic and dia-stolic blood pressure; total, LDL, and HDL cholesterol; and fasting triglycerides. RESULTS: The median hsCRP concentration in these untreated individuals showedmodest regression to the mean over time, declining from 3.8 mg/L at random-ization to 3.4 mg/L at 4 years. Tracking correlations for hsCRP over time were comparable to those for blood pressure and LDL cholesterol, but lower than those for HDL, fasting triglycerides, and total cholesterol. The intraclass correlation for repeated hsCRP measure-ments was 0.54 (95 % CI, 0.53–0.55) without covariate adjustment and 0.50 (95 % CI, 0.49–0.51) after adjust-ment for demographic, lifestyle, and comorbidity determinants. CONCLUSIONS: Concentrations of hsCRP show strong tracking, even after selection of individuals with ini-tially high values. Without statin therapy, increased concentrations of hsCRP generally remain high over time