Serum endothelin-1 and endothelin-2 levels in healthy controls and circadian hypertension phenotypes: A comparison of dipper and non-dipper patients

This study identifies serum endothelin-1 is a strong, independent marker of the non-dipper hypertensive phenotype, which is associated with increased cardiovascular risk. The preservation of low endothelin-1 levels in dipper hypertension patients reflects intact endothelial and circadian regulation, whereas the absence of this response in non-dipper patients indicates impaired vascular adaptation. The inverse association of endothelin-2 with non-dipper status further suggests a protective buffering role that may be attenuated by increasing metabolic burden.