Corelation Between Parental History Of Hypertension And Masked Hypertension

Masked hypertension (MH) is a kind of abnormal blood pressure disease, which characterized by normal clinic blood pressure and elevated ambulatory blood pressure.MH is a serious threat to people's health which can cause various organs damage such as heart and vascular. Traditionally, the diagnosis of hypertension is based on clinic blood pressure (BP), but the use of ambulatory blood pressure monitoring (ABPM) along with clinic BP has made the classification of hypertension more complex.There are many peoples which clinic blood pressure is higher than 140 /90 mm Hg (1 mm Hg= 0.133 kPa), but the 24-hours ambulatory blood pressure is normal,and without obvious organ damage, then people named it for white-coat hypertension. Another kind of blood pressure is characterized by normal clinic blood pressure and elevated ambulatory blood pressure, because most blood pressure is meatured in the clinic, less use of ambulatory blood pressure monitoring, so the disease is often ignored by cardiologist.Until 1999, Liu et al first described this clinical phenomenon and the damage caused by it. They found that the left ventricular and carotid artery in patients with this disease is different with that in normotensive subjects. In 2002,Pickering et al named it for MH.The commonly used diagnostic criteria:Clinic BP<140/90 mmHg, home BP>135/85 mmHg, or daytime BP>135/85 mmHg and/or 24 h BP>130/80 mmHg.Hypertension is a serious threat to human health and is one of the most common diseases, which is one of the risk factors of cardiovascular and cerebrovascular events.A number of researches shows that its occurrence is affected by genetic and environmental factors, and has obvious family aggregation.The majority of patients with hypertension can be traced to the parental history of hypertension. One reserch was conducted to explore the relationship between MH and family heredity in adolescent patients.They found that there was a significant increase in cases with positive parental history of hypertension in MH group compared with that in the normal blood pressure group.In that research, only 45 cases of MH were investigated in the parental history of hypertension, and the incidence of MH in adults was not studied.Therefore, whether MH also has a family clustering similar to hypertension is one of the key issues discussed in this paper.In 1999, Liu et al first rasearch the relatoin between MH and target organ damage, they found that in patients with MH, left ventricular mass index and carotid artery intima-media thickness were higher than those in normotensive subjects.Later studies demonstrated that MH was associated with carotid artery intima injury, decreased coronary flow reserve, increased left ventricular mass index, left ventricular hypertrophy, and increased diabetes mellitus.Studies have also indicated that MH patients are more likely to develop into hypertension. Therefore, whether the parental history of hypertension will affect the target organ damages caused by MH is another important issue in this study.If finding a relationship between MH and parental history of hypertension, we can carry out the ambulatory blood pressure monitoring for the population with a parental history of hypertension, which will improve the detection rate of MH, so as to achieve the early prevention, diagnosis and treatment of MH patients, to achieve the purpose of protecting target organs. This study aims to explore the parental history of hypertension in adults with MH andfind the influence of parental history of hypertension on the incidence of MH and target organ damage.Objective:To investigated the corelation between parental history of hypertension and masked hypertension including the influence of parental history of hypertension on the morbidity of MH and the target organ damage.Subjects:The continuous samples selected from 10040 cardiovascular patients (from January 2010 to April 2015) were averagely divided into three groups-250 subjects in hypertension group,250 subjects in normotension group and 250 in masked hypertension group. Inclusion criteria:18 to 65 years old. Exclusion criteria:(1) Metabolic disorders, immune system disorders, cancer, blood disorders, liver and kidney dysfunction, stroke and multiple organ failure; (2) A history of recent infection, taking the contraceptive drug in the past half year or alcohol abuse; (3) Coronary heart disease, after percutaneous coronary intervention therapy,acute coronary syndrome, malignant arrhythmia and cardiac failure; (4) pregnancy or breast-feeding women.Diagnostic criteria Hypertension:Different day 3 BP>140/90mHg or previous antihypertensive drugs[13]; MH:Clinic BP<140/90 mmHg, home BP>135/85 mmHg, daytime BP>135/85 mmHg and/or 24 h BP>130/80 mmHg [4, 14]; Normal:office BP< 140/90 mmHg, daytime BP<135/85 mm Hg and 24 h BP <130/80 mmHg.Methods:1. General data collectionGeneral data including age, sex, smoking and drinking history, parental history of hypertension, medical history, height, weight, etc information and calculate body mass index (BMI)were recorded by professionally trained staff,. Parental history of hypertension:one or both of the parents with essential hypertension.2. Blood pressure measurement1.Standard mercury column blood pressure gauge, blood pressure was measured after 10 minutes rest in sitting position, no smoking or drinking coffee or tea within 30 minutes, emptying the bladder; 2.he subjects were seated, baring arm, placing arm and heart at the same level.3.The cuff dinged to the subjects'upper arm, the lower edge of the cuff should be in 2.5cm above the elbow. The stethoscope probe was placed in the brachial artery pulse.4. When measuring BP, rapid inflation, when the air bag pressure to reach the radial artery pulse disappeared, and then increased 30mmHg, and then to a constant rate (2-6mMHg/s) slow bleeding. Forsubjects with slow heart rate, the rate of deflation should be more slowly. After obtaining diastolic pressure readings, the air bag pressure were deflated rapidly to zero. We conducted 3 times continuous measurementof blood pressure,and the interval between each time was 1min,then take the average value of 3 measurements [12].3.24-h ambulatory blood pressure monitoring (ABPM)Dynamic blood pressure monitor (AM R-4, Welchallyn manufacturing) was adopted in our research. The cuff attached to the left upper arm, and the monitor charged for 24 hours intermittently to monitor ambulatory blood pressure. During the daytime (6:00-22:00) and night (22:00 to 6:00) monitoring time was separated by 30 minutes, and lasted for 1 hour once. Blood pressure monitoring sustained for a total of 24 hours. During the monitoring period, subjects were still engaged in daily activities. Blood pressure monitoring data include:24 h average systolic blood pressure, daytime and nighttime systolic blood pressure; 24 h mean diastolic blood pressure, daytime and nighttime diastolic blood pressure[12].4. Cardiac ultrasonographyUsing (IE33, American GE company production) color Doppler ultrasound diagnostic instrument, probe frequency 3-11 Hz, measurement of ventricular wall thickness, left atrial diameter and aortic valve maximum blood flow velocity, and calculating the left ventricular mass index. Formula:left ventricular mass index= left ventricular mass/body surface area, Left ventricular mass=1.04* [(left ventricular end diastolic diameter+end diastolic ventricular septal thickness+end diastolic left ventricular posterior wall thickness)3-left ventricular end diastolic diameter 3]-13.6 (each heart detection index unit is cm), Body surface area=0.0061* height (CM)-0.0128* weight (kg)-0.1529.5. Carotid artery ultrasonographyUsing (IE33, American GE company production) color Doppler ultrasound diagnostic instrument, probe frequency 3-11Hz,the subject in the supine position, pading cushion in the back of neck, the neck is fully exposed, Starting Profiler from the root of the neck, then moving along the blood vessels to the head, and recording both sides'carotid intima-media thickness (IMT)?whether there is atherosclerotic plaque and its diameter?quantity.6. Laboratory examination5mL venous blood was taken after fasting 12 hours, using Hitachi 7170 automatic biochemical analyzer to detect blood glucose, total cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, uric acid.7. Statistical analysisSPSS21 software was used for statistical analysis. Among the three groups data were compared with single factor variance analysis; Fishers Least Significant Difference (LSD) test was used to compare the data between the two groups. Chi square test was used to count data,and rank sum test was used for the significance analysis. Logistic regression analysis was used to analyze the relationship between the prevalence of MH and other variables, and the differences were statistically significant (P< 0.05)Results:1. There were a total of 70 patients with parental history of hypertension in masked hypertension group (28%); 87 in hypertension group (34.8%) and 26 in normotension group(10.4%). The proportion of patients with parental history of hypertension in masked hypertension group is higher than that in the normotension group (P<0.001), and has no difference in hypertension group. In the multinomial logistic regression analysis, parental history of hypertension and body mass index were positively related to masked hypertension and hypertension suggesting that the parental history of hypertension and body mass index were risk factors of masked hypertension and hypertension.2. Left ventricular mass index (85.64±17.7 vs 80.50±15.53) and maximum blood flow velocity of aortic valve (115.74±16.54 vs 112.40±14.21) in masked hypertension group are higher than those in the normotension group; In masked hypertension group(P<0.05), the left ventricular mass index (89.22±19.08 vs 84.25±16.99),maximum blood flow velocity of aortic valve(119.19±14.97 vs 114.39±16.96) and carotid intima media thickness(IMT) of patients with parental history of hypertension are higher than those without parental history(P<0.05).Conclusion:1. People with parental history of hypertension suffer higher risk of masked hypertension,2.. Parental history of hypertension will aggravate degree of heart and carotid artery damage.