Hypertension In 2017— Individual VS Public Health Goals

Hypertension has obviously been one of the main stays of cardiovascular (CV) medicine for a long time and it is the single most modifiable CV risk factor in the world today. Hypertension had a great deal of evolution since publication of the landmark 1977 Joint National Committee report there has been progressive improvement in awareness, treatment, and control of high blood pressure (BP). Although several BP guidelines have been published since 2003, the 2017 guideline is the most comprehensive that has a new classification, definition and different goals for BP reductions.

The new guideline defines normal BP as below 120/80 mmHg and elevated blood pressure as 120 to 129 mm Hg systolic with a diastolic pressure below 80 mm Hg. Stage 1 hypertension is defined as 130 to 139 mmHg systolic or 80 to 89 mmHg diastolic, and stage 2 hypertension as 140/90 mm Hg or higher (the old definition of hypertension). What is now called stage 1 hypertension was previously labeled “prehypertension” a term meant to alert patients and to prompt physicians to provide lifestyle education to help delay development of hypertension.

Adults with an average systolic BP of 130 to 139mmHg or diastolic BP of 80 to 89mmHg have about a 2-fold increase in CV disease risk compared with a normal BP (SBP < 120 mmHg and DBP < 80 mmHg). Unlike previous guidelines, the 2017 guideline emphasizes individualized CV risk assessment and aggressive management of BP at levels of 140/90 mm Hg or higher in patients with a 10-year risk of CV events of more than 10%. Although the 10% 10-year-risk designation is not based on randomized, controlled trials, patients with BP of 130 to 139/80 to 89 mmHg would still receive non-pharmacologic treatment, unless they had a 10-year risk above 10%; in that case, a single antihypertensive agent is recommended, in concert with lifestyle changes.

Accurate and proper measurement of BP is the first most important and critical step to the diagnosis hypertension. In addition to careful BP measurement, the new guideline highlights the increasingly important role of out-of-office BP readings for confirming hypertension and recognizing white-coat and masked hypertension. It also emphasizes contemporary strategies to improve BP control, including ways to successfully implement and sustain non-pharmacological interventions, improve medication adherence, use a structured team-based approach to care, and take advantage of health information technology.

According to the new BP definitions, prevalence of hypertension increased and there is concern that a new disease designation can become a mandate for pharmacologic treatment without consideration of the patient’s risk level. However, this was an area of discussion and was explained very well in this version of guidelines. Although there are positive aspects of targeting higher-risk people with lower blood pressure for risk-factor modification, an individualized approach to hypertension can help determine the best choice for first-line therapy.

In the public health level there is a morbidity and mortality benefit, but in the individual patient level this may be hard to achieve specifically in asymptomatic patients. We are still not doing well in lowering BP and almost half of the patients are not achieving the individualized goals. However, this is the biggest place where we can have an effect and obviously why there is a national concern! It’s reasonable to consider more aggressive treatment goals in the highest-risk patients, but understanding the guideline and considering each patient according to their risk factors and complex medicine problems become more critical.

Fawaz Alenezi Headshot
Dr. Fawaz Abdulaziz M Alenezi is a Clinical Imaging Fellow at the Duke University Health Systems. He conducts medical research on the derivation and validation of novel echocardiographic approaches to myocardial deformation and a new echocardiographic technique which assists patients with heart ventricular function.


Manual Versus Automated Office Blood Pressure Measurements

Although the awareness and treatment of hypertension has increased steadily over the past decade, it is estimated that approximately 50% of patients are still not adequately controlled. However, blood pressure measurement techniques vary widely and results from studies are difficult to compare. Further, office BP measurements depend on time, resources, and equipment.

In our referral Cardiology-Hypertension Clinic blood pressure is measured in different ways by different providers:BP measurement tools

  1. Manual
  2. attended automated office BP (AOBP) with 3 consecutive readings (Omron) or
  3. unattended attended automated office BP (AOBP) with 3 consecutive readings (Omron) or 6 consecutive readings (BPTrue).

“Attended” means that trained personnel stays in the room, while in unattended measurements trained personnel leaves the room and monitors are either programmed to take 3 or 6 consecutive readings.

These different approaches make it difficult to compare BP levels and to adjust medication to achieve target BP.

So what is the best way to measure blood pressure and which is the one we should stick to?

It is known that BPs taken manually can differ from those taken using an automated device in the clinic or office. Several studies have shown that manually taken BPs can be higher than AOBP.  Further, many clinicians prefer AOBP over manual BPs since it is an easy way to check BP several times.

With advances in technology, unattended AOPB measurements are possible. Research suggests that unattended blood pressure measurements are significantly lower than attended blood pressure measurements.

Clinical trials using AOBP usually pre-specify how to measure BP i.e. either attended while trained personnel stays in the room or unattended i.e. medical staff comes back after a few minutes and retrieves BP readings.

The importance of a consistent way to measure BP has come under scrutiny in the SPRINT study.

Although blood pressure measurements in this study were obtained using an automated measurement device, there were substantial differences in the methods used by the different SPRINT centers. In particular, medical staff were inconsistently present or absent when blood pressure readings were taken, between centers and perhaps within centers.

Blood pressure in SPRINT was defined as the average of three measurements taken with an automated measurement device. But until now it has not been entirely clear whether these measurements were obtained in the presence or absence of medical staff.

Results of a survey for the SPRINT trial showed that patients were completely alone during the measurement period at 43% of the sites and were alone (unattended) for part of the time at 29% of the sites. However, within sites significant internal variation in their BP measurement techniques (unattended and attended AOBP) may have occurred.
What is clear is that there are a variety of methods currently employed to measure BP in clinical trials and in the office, and that technique, environment, and equipment can influence BP levels obtained.

To put that in perspective for clinical practice we should take this into consideration and report how BP was measured when we communicate with our patients or colleagues.

Bp levels

Tanja Dudenbostel Headshot

Tanja Dudenbostel is an Internist, Hypertension Specialist within Cardiology at the University of Alabama at Birmingham where I divide my time as an Assistant Professor between clinical research and seeing patients in cardiology.