Hypertension is the most common cardiovascular disease and is the most important risk factor for serious diseases such as stroke, heart failure, myocardial infarction and renal insufficiency. According to the Fourth National Nutrition and Health Survey in 2002, the prevalence of hypertension among adults aged ≥18 years in China was 18,8%, with the prevalence among elderly people aged ≥60 years as high as 49,1%. According to the data of the China Cardiovascular Disease Report 2014, nearly 300 million people suffer from hypertension in China. If timely diagnosis can be made and various types of antihypertensive drugs are applied for antihypertensive treatment, blood pressure can be effectively controlled and the incidence of various cardiovascular and cerebrovascular complications can be reduced.
Ambulatory blood pressure monitoring technology can more accurately and comprehensively reflect the overall situation of a person’s blood pressure, and has become an indispensable detection tool for hypertension management.
Although ambulatory blood pressure monitoring technology has been introduced into China for more than 20 years, there are still some outstanding problems in its clinical application. For this reason, several domestic experts have jointly prepared the “Chinese Expert Consensus on Clinical Application of Ambulatory Blood Pressure Monitoring”, which will provide a strong help for Chinese medical workers to understand and make good use of ambulatory blood pressure monitoring technology.
On the selection of ambulatory blood pressure monitor and testing requirements
Ambulatory sphygmomanometers that have been independently clinically validated according to international standards should be selected and regularly calibrated during clinical use to ensure their accuracy.
Testing method
An appropriately sized cuff should be selected. Before monitoring, office blood pressure should be measured, and bilateral upper arm blood pressure should be measured. If the difference in blood pressure between the two upper arms is ≥10 mmHg, the upper arm of the side with high blood pressure should be selected for ambulatory blood pressure monitoring; if the difference between the two sides is <10 mmHg, the non-dominant arm should be selected for monitoring. Blood pressure should be measured manually 2 times after loading the sphygmomanometer and at the end of monitoring to test whether the sphygmomanometer is working properly.
Monitoring protocol
It should be ensured that the monitoring period is >24h and that more than 1 blood pressure reading is taken every hour, if possible. Typically, measurements are taken every 20 min during the day and every 30 min during sleep at night. Generally, monitoring can be considered effective if the valid readings are at least 70% of the set readings, 20 or more readings are calculated for daytime blood pressure, and 7 or more readings are calculated for nighttime blood pressure. If the above conditions are not met, the monitoring should be repeated.
Clinical applications
1.Diagnosing hypertension and improving the accuracy of hypertension diagnosis.
2.Assessing cardiovascular risk and improving the level of cardiovascular risk assessment.
3.To assess the effect of antihypertensive treatment and improve the quality of antihypertensive treatment.
Indications
1.Increased blood pressure found in the office or home blood pressure monitoring, suspected “hypertension”, the average blood pressure in the range of 140-179/90-109mmHg.
2, diagnosed hypertension and has received antihypertensive treatment, if ≥ 2 drugs adequate treatment, blood pressure is still ≥ 140/90mmHg, or the average value of home blood pressure ≥ 135/85mmHg.
3, diagnosed hypertension and have received antihypertensive treatment, if the average value of the office blood pressure measured several times <140/90mmHg, still occurred cardiovascular and cerebrovascular complications or new target organ damage or progressive aggravation of target organ damage.
4, not taking antihypertensive drugs, office blood pressure <140/90, but home blood pressure ≥135/85 or office or home blood pressure 120-139, 80-89 mmHg, but there is target organ damage, and there are no other cardiovascular risk factors.
In addition, ambulatory blood pressure monitoring can be used to rule out “white coat hypertension”.
Indicators used to diagnose hypertension
Current ambulatory blood pressure indicators used to diagnose hypertension include the average of all blood pressure readings for 24h, daytime and nighttime systolic and diastolic blood pressures.
In addition, daytime and nighttime are preferably based on the wake up and bedtime times recorded on the ambulatory blood pressure monitoring diary card. If daily activity information is not recorded, daytime (8:00-20:00, 12h) and nighttime (23:00-5:00, 6h) can also be defined based on fixed time periods. Xinjiang, Tibet and other western provinces should be deferred by 2h according to Beijing time.
Criteria for the diagnosis of hypertension
The criteria for diagnosing hypertension are: 24h mean systolic/diastolic blood pressure ≥ 130/80, daytime ≥ 135/85 mmHg or nighttime ≥ 120/70 mmHg; by comparing with the office blood pressure, the following diagnoses can be further established, including “white coat hypertension” in those who are not taking medication (office blood pressure ≥ 140/ 90 mmHg with normal 24-h, daytime, and nighttime blood pressure), “covert hypertension” (office blood pressure <140/90 mmHg with elevated 24-h, daytime, or nighttime blood pressure), "white coat controlled hypertension" in patients receiving antihypertensive therapy, and "covert hypertension " and "covert uncontrolled hypertension" (blood pressure criteria were the same as those for untreated patients).