Cardiovascular risk prediction by N-terminal pro brain natriuretic peptide and high sensitivity C-reactive protein is affected by age and sex.

BACKGROUND: Previous studies have shown that the urine albumin/creatinine ratio (UACR), high sensitivity C-reactive protein (hsCRP) and N-terminal pro brain natriuretic peptide (Nt-proBNP) predict cardiovascular events in a general population aged 41, 51, 61 or 71 years. This study investigated the impact of age and sex on their prognostic performance in a subgroup of 1994 apparently healthy individuals without diabetes, previous stroke or myocardial infarction, who did not receive any cardiovascular, antidiabetic or lipid-lowering medication.

METHODS: In 1993-1994 we recorded cardiovascular risk factors, UACR, hsCRP and Nt-proBNP. The composite cardiovascular endpoint (CEP) of cardiovascular death and non-fatal stroke or myocardial infarction was assessed after 9.5 years.

RESULTS: In Cox regression analyses predicting CEP, the effects of log(hsCRP) and log(Nt-proBNP) were modulated by sex (P < 0.05) and age (P < 0.05), respectively. The effect of logUACR was not significantly modulated by age or sex. Log(hsCRP)/SD did not predict CEP in women, but did predict CEP in 41 plus 51-year-old men [hazard ratio (HR) 1.71; 95% confidence interval, 1.1-2.6; P < 0.05] and 61 plus 71-year-old men (HR 1.64; 1.3-2.2; P < 0.001). Log(Nt-proBNP)/SD predicted CEP in 61 plus 71-year-old women (HR 1.74; 1.2-2.5; P < 0.01) and in 61 plus 71-year-old men (HR 1.58; 1.3-2.0; P < 0.001).

CONCLUSION: Elevated hsCRP, reflecting early atherosclerosis, predicted CEP even in 41 plus 51-year-old men. Elevated Nt-proBNP, reflecting subclinical cardiovascular damage, predicted CEP in 61 plus 71-year-old subjects. Elevated UACR, reflecting endothelial dysfunction as well as microvascular damage, predicted events independently of age and sex, but primarily in 61 plus 71-year-old subjects.