As for differences between cohorts, the BIOSTAT-CHF cohort used by Tromp et al.,11 though similar in demographics, included HFrEF patients that had a larger number of comorbidities and higher baseline NT-proBNP compared to the current study, and might therefore describe additional subphenotypes that emerged as the condition grew more severe. The gene discussed is NPPB; the disease is congestive heart failure.