High BNP predicts stroke or systemic embolism in very elderly NVAF patients

In very elderly nonvalvular atrial fibrillation (NVAF) patients who are ineligible for standard anticoagulation, increasing levels of B-type natriuretic peptide (BNP) appear to be correlated with higher risks of stroke or systemic embolism (SSE), reports a new study.

Conducting a subanalysis of the ELDERCARE-AF trial, the researchers enrolled 984 patients (mean age 86.6 years), of whom 428, 300, and 256 were deemed to have low (<200 pg/mL), moderate (200–<400 pg/mL), or high (≥400 pg/mL) BNP, as measured by chemiluminescence enzyme immunoassays.

SSE developed in seven patients in the low BNP group, yielding an incidence rate of 1.2 percent. This increased progressively in the moderate (n=24; 5.9 percent) and high (n=28; 8.6 percent) BNP subgroups.

Cox proportional hazards analysis, adjusted for potential confounders, revealed that SSEs were significantly more likely to develop in those with moderate vs low BNP (adjusted hazard ratio [HR], 3.82, 95 percent confidence interval [CI], 1.60–9.12; p=0.0025). A similar and stronger effect was reported among those with high vs low BNP, in whom SSE risk was nearly five times higher (adjusted HR, 4.76, 95 percent CI, 1.93–11.76; p=0.0007).

Strokes were likewise significantly more likely to arise in those with moderate (adjusted HR, 3.30, 95 percent CI, 1.35–8.08; p=0.0089) and high (adjusted HR, 4.86, 95 percent CI, 1.94–12.18; p=0.007) vs low BNP.

In contrast, no among-group differences were reported for safety outcomes such as major bleeding, intracranial haemorrhage, and gastrointestinal bleeding.