Epicardial fat thickness is associated with non-dipper blood pressure pattern in patients with essential hypertension

Epicardial fat tissue reflects visceral adiposity and is a suggested cardiometabolic risk factor. Patients with abdominal obesity have an increased prevalence of the non-dipper blood pressure (BP) pattern, but it is unclear whether the same is true of patients with increased epicardial fat thickness (EFT). The association between EFT and circadian BP changes in patients with recently diagnosed essential hypertension was examined.

Sixty hypertensive patients underwent echocardiography, treadmill stress testing, and 24 hours of ambulatory BP monitoring. Epicardial fat thickness and left ventricular mass (LVM) index were measured by using transthoracic echocardiography. The patients were categorized into two groups according to their BP pattern (group 1, non-dippers; group 2, dippers).

The mean EFT and LVM of patients in group 1 (n = 24) (EFT, 7.6 ± 2.1 mm; LVM, 130 ± 31.2 g/m(2)) were significantly greater than those of group 2 (n = 36) (EFT, 5.5 ± 1.2 mm, P = .0001; LVM, 107 ± 23.7 g/m(2), P = .002). The average systolic BP over 24 hours (BP(s) 24) and average diastolic BP over 24 hours (BP(d) 24) of group 1 (BP(s) 24, 151.1 ± 17.6 mm Hg; BP(d) 24, 94.1 ± 16.5 mm Hg) were significantly higher than those of group 2 (BP(s) 24, 136.7 ± 11.9 mm Hg, P = .0001; BP(d) 24, 84.6 ± 10.6 mm Hg; P = .008). Multivariate backward logistic regression analysis demonstrated that the non-dipper BP pattern was associated with EFT (standardized β coefficient = 0.87, P = .005) and LVM (standardized β coefficient = 0.43, P = .016). An EFT ≥ 7 mm was associated with the non-dipper BP pattern with 44% sensitivity and 94% specificity (receiver operating characteristic area under curve of 0.72, 95% CI [0.59-0.83], P = .0007).

Epicardial fat thickness was above average in newly diagnosed, untreated hypertensive patients with non-dipper BP pattern. The echocardiographic measurement of EFT may be used to indicate increased risk of hypertension-related adverse cardiovascular events.