Pulmonary Arterial Hypertension: Improving Survival Rates
Monitoring BNP levels in patients with PAH is an inexpensive and useful method for survival prediction.
Monitoring the plasma brain natriuretic peptide (BNP) level in individuals with pulmonary arterial hypertension (PAH) may aid clinicians in therapeutic decision-making and overall prediction of 5-year survival rates, according to an article published by Chest.
Researchers identified 1426 individuals from the multicenter, observational US-based Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL) to determine the clinical relationship between BNP levels and overall survival rates in individuals with PAH. Individuals were placed into 4 groups based on their baseline and follow-up BNP values at 1 year, with low and high BNP thresholds set at ≤340 and >340 pg/mL, respectively: low-low, low-high, high-high, and high-low.
Study results found that individuals with a high baseline BNP (n=375) have a higher mortality risk compared with those with a low baseline value (n=1051; hazard ratio [HR], 3.6; 95% CI, 3.0-4.2, P <.001). Overall, the groups with the highest and lowest mortality risks at ≤1 year were found to be those individuals in the high-high and low-low groups (HR, 0.23; 95% CI, 0.19-0.27), with a lower 5-year risk for death in the low-low group compared with the high-high group (HR, 0.12; 95% CI, 0.13-0.19; P <.001). Five-year survival rates in individuals with a baseline BNP of ≤340 and >340 pg/mL were found to be 72.9% (95% CI, 70.0%-75.6%) and 32.5% (95% CI, 27.4%-37.8%), respectively.
Although BNP levels remained low in 62.9% of individuals with a low baseline BNP, levels continued to rise in 12.6% of patients until approximately 3 years. Individuals with high BNP had levels that decreased over time to a low level (9.1%); however, 15.4% of individuals with high levels at baseline remained at the same level at last assessment.
Within 1 year, individuals with high BNP at baseline whose levels decreased to a low BNP (n=75) experienced only 39 events and a reduced death risk of 40% (HR, 0.60; 95% CI, 0.43-0.85; P =.004). Individuals in the low-high group were found to have a higher risk for death compared with those in the low-low group at both 1 and 5 years (HR, 3.2 [95% CI, 2.35-4.46; P <.001] and HR, 3.9 [95% CI, 3.02-4.97; P <.001], respectively). In addition, individuals in the high-high group had a higher risk for death compared with those in the low-high group (HR, 0.72 [95% CI, 0.52-1.004; P =.05] and HR, 0.61 [95% CI, 0.48-0.78; P <.001], respectively). Five-year survival rates in individuals with a baseline BNP of ≤340 and >340 pg/mL were noted to be 72.9% (95% CI, 70.0%-75.6%) and 32.5% (95% CI, 27.4%-37.8%), respectively.
Researchers concluded that trending BNP levels in individuals with PAH is an inexpensive and useful method for strongly predicting their 5-year mortality risk at a predictive threshold level of 340 pg/mL. Therefore, clinicians should consider the use of this biomarker in aiding treatment decision making.
Frantz RP, Farber HW, Badesch DB, et al. Baseline and serial brain natriuretic peptide level predicts 5-year overall survival in patients with pulmonary arterial hypertension: data from the REVEAL registry [published online January 16, 2018]. Chest. doi:10.1016.j.chest.2018.01.009