Adrenomedullin and non-dipping circadian pattern in newly diagnosed essential hypertension

Abstract

OBJECTIVE There is frequently a relationship between nocturnal hypertension and non-dipping pattern and endothelial dysfunction. Studies conducted previously have indicated that adrenomedullin (AM) (a potent, long-lasting, vasodilatory peptide) is capable of regulating endothelial cell function. The aim of the current research is to investigate the association between absolute night-time blood pressure (BP) and circadian BP pat-tern with serum AM and high-sensitivity C-reactive protein (hsCRP) levels in cases in whom untreated arterial hypertension has been newly diagnosed. METHODS Ambulatory BP monitoring was performed in 100 individuals with hypertension (50 dippers,50 non-dippers) and 50 healthy controls for 24 hours. Measurement and recording of AM and hsCRP serum levels were performed. RESULTS A strong correlation between night-time BP levels and AM and hsCRP levels was determined(p<0.001). On the contrary, higher AM levels were determined in the non-dipper group compared to the dipper and normotensive groups (non-dipper group, 258±27 pg/mL; dipper group, 199±30 pg/mL; normotensive group, 150±11 pg/mL; p<0.001). The non-dipper group exhibited significantly higher hsCRP levels in comparison with the remaining two groups (p=0.017). An independent association was determined between AM (p=0.014) and hsCRP (p=0.032) and a non-dipping pattern in a multivariate logistic regression analysis. CONCLUSIONS The nocturnal hypertensive and non-dipper groups exhibited increased AM levels. An independent association was identified between AM and hsCRP and a non-dipping pattern. It is implied that increased AM levels in individuals with non-dipper hypertension may be related to a longer exposure time to high BP. The mentioned findings indicate a potential future part of AM in identifying patients with hypertension that are at higher risk of target organ damage (Tab. 3, Fig. 4, Ref. 41).