Salivary B-type natriuretic peptide: a new method for heart failure diagnosis and follow-up

BACKGROUND: Frequent hospital admissions and reduced quality of life are the main complications of heart failure (HF). Plasma B-type natriuretic peptide (BNP) levels have been considered as a cost-effective method of screening for left ventricular dys-function. Studies regarding BNP-guided therapy revealed reduction in death or hospital stay for HF. AIM: As saliva has fewer limitations than blood in regard to sampling, the aim of the present study was to test if salivary BNP concentration might be a new biomarker in patients with chronic HF. METHODS: This pilot study involved 35 admitted patients with decompensated HF diagnosis and 35 HF patients who had come for a check-up at the Department of Cardiology. The control group consisted of 25 people with no history of cardiac events. Saliva and plasma samples of all the participants were collected. RESULTS: Mean plasma NT-proBNP was found at higher levels in admitted HF patients compared to outpatient HF (9.37 vs. 6.62 pg/mL, p < 0.001) and control groups (9.37 vs. 4.69 pg/mL, p < 0.001). Also, mean salivary BNP levels were higher in admitted patients with HF (6.50 ng/L, p < 0.001); and outpatient HF group (5.87 ng/L, p = 0.02) compared to the control group (5.64 ng/L). CONCLUSIONS: Our study demonstrated that BNP could be detected in saliva and that the level is higher in HF patients, especially symptomatic ones. This means that salivary BNP may be useful in the diagnosis and follow-up for patients with HF, especially in emergency settings.