Usefulness of C-reactive protein in resistant high blood pressure

This paper studied the usefulness of C-reactive protein (CRP) in predicting outcomes in resistant high blood pressure. This study found that high CRP levels were predictive of worse outcomes. 

C-reactive protein is a molecule in the body that indicates inflammation (body’s reaction to injury or infection). It can also be used to predict risk of heart disease in patients with diabetes, high blood pressure, and certain other heart diseases. In patients with resistant high blood pressure, blood pressure remains elevated even when at least 3 different drugs are used. It is not clear whether CRP could be used to predict outcomes in patients with resistant high blood pressure. 

476 patients with resistant high blood pressure were studied. Their blood pressure and CRP levels were measured. 89.2% of patients were followed for an average of 9 years. The average CRP level was 3.8 mg/l.

Patients with high CRP levels were younger, more frequently women, obese, and physically inactive than those with CRP below average. They were more likely to have an enlarged left side of the heart and coronary heart disease, and higher blood pressure in the daytime than patients with low CRP levels.

Over 9 years, there were 21 non-fatal strokes, 20 non-fatal heart attacks and 62 deaths from heart disease related causes. There were 120 deaths from any cause.

Patients with above average CRP levels had a twice the risk of major cardiovascular events such as heart attacks, stroke and heart failure. They had an 86% higher risk of death from heart-related causes. Patients with high CRP were 2.04 times more at risk of have heart disease-related events such as heart attacks. Patients with high CRP were 2.72 times more at risk of events like stroke. CRP levels were predictive of death from heart-related causes. However, CRP was not predictive of death from any cause.

The authors concluded that high CRP levels predict worse outcomes in patients with resistant high blood pressure.