The study group included 100 hypertensive patients recruited from the hypertension clinic in Assiut University Hospital, during the period from June 2016 to July 2017. Patients were divided into two groups, either controlled or uncontrolled office BP according to the European Society of Cardiology (ESC) guidelines 2013 (≥ 140 mmHg systolic BP (SBP) and/or ≥ 90 mmHg diastolic BP (DBP).
A detailed history was obtained, and complete clinical examination was performed including patients’ weight and height to calculate body mass index (BMI).
Office pressure blood pressure measurement was done according to ESC 2013; we measured the systolic and diastolic blood pressure and compared the results with those of ABPM and NICBP.
For measurements of ABPM, we used NICE recommendations to ensure that at least two measurements per hour are taken during the person’s usual waking hours. We used the average value of at least 14 measurements taken during the person's usual waking hours to confirm a diagnosis of hypertension. The device was programmed to obtain BP readings at 30-min interval during the day (08:00–22:00 h) and at 60-min intervals during the night (22:00–08:00 h) . We measured systolic and diastolic blood pressure and compared the results with those of office BP and NICBP.
Blood pressure varies over 24 h with a number of well-recognized patterns. Dippers are individuals characterized by at least a 10% decline in nocturnal BP compared to their awake BP . Most of the patients are dippers. Non-dippers are individuals having blunted or absent blood pressures which decline during sleep . Approximately 10–30% of patients are “non-dippers,” and in our study, non-dippers represent 34% of our patients.
We obtained the central blood pressure curve of our patients in a quiet, temperature-controlled examination room at the hypertension clinic. Three measurements were taken with a 2-min break between them by using Mobilograph device. The procedure was performed with the patient in a supine position and using an adequately sized cuff (the Mobil-O-Graph 24 h PWA ABPM device (IEM, Stolberg, Germany) [12, 13]).
We measured systolic and diastolic blood pressures and compared them with the measurements of both office and ABPM.
We measured pulse wave velocity (m/s) (PWV) by Mobilograph and compared the result and age to detect the degree of arterial thickness related to hypertension. The slower the pulse wave velocity is, the better the heart health is. However, normal pulse wave velocity values vary according to age. We measured also the mean arterial pressure (MAP) and augmentation index (AI).
Blood samples were collected to measure serum creatinine and to exclude patients with a glomerular filtration rate of < 30 ml/min/1.73 m2. The measurement of GFR was obtained by the Cockcroft-Gault formula study equation.
ECG was used to measure the left ventricular hypertrophy (LVH) using “Sokolow-Lyon ≥ 38 mm . Echocardiography using Phillips IE33 ultrasound system was performed to all patients in addition to controls. Images were obtained from the short-axis view and longitudinal parasternal 4-chamber, 2-chamber, and 5-chamber slices. LV mass (LVM) and LVMI were calculate using LVMI = LV mass/BSA calculated by the Mosteller formula . Ejection fraction (EF %) was calculated using Simpson’s method .
Carotid intimal medial thickness (CIMT) was measured with Doppler ultrasound (US) on the carotid artery to detect increased thickness related to hypertension. The intima-media complex can easily be distinguished from the surrounding tissue in US images, and the distinct borders allow for manual as well as automatic measurements of the CIMT. Damage is defined as the presence of CIMT > 0.9 mm or plaque .
ABI was calculated by measuring the systolic blood pressure from both brachial arteries and from both the dorsalis pedis and posterior tibial arteries at rest in the supine position. The systolic pressures were recorded with a handheld 5- or 10-mHz Doppler instrument [18, 19]. Normal ABI ranges from 1.0 to 1.4; values above 1.4 suggest a non-compressible calcified vessel. However, a value below 0.9 is considered diagnostic of peripheral arterial disease (PAD).