What’s new in this year’s guidelines that may impact your practice?
By Shelley Diamond, BScPhm
Illustration by Martin Bregman
- BLOOD PRESSURE MEASUREMENT: AUTOMATED (OSCILLOMETRIC) OFFICE BLOOD PRESSURE (AOBP), TAKEN WITHOUT PATIENT-HEALTH PROVIDER INTERACTION, IS THE PREFERRED METHOD OF MEASURING IN-OFFICE BLOOD PRESSURE.
This is now recommended over the manual auscultatory (mercury) method using a sphygmomanometer. This reinforces the value of blood pressure measurement in the absence of a healthcare professional (e.g. home blood pressure monitor, blood pressure kiosk) since it provides more accurate results, avoids the risk of conversation during readings and eliminates ‘white coat hypertension’. Twenty-four hour ambulatory monitoring is still the preferred method for out-of-office measurement since it assesses blood pressure in the day as well as at night.
- LIPID MEASUREMENT: FASTING NO LONGER REQUIRED
People with hypertension should have a lipid panel done as part of their routine testing. Both fasting and non-fasting lipid tests are now considered acceptable. This recommendation was based on a large Canadian community-based cross-sectional study1, and is consistent with other studies that demonstrated minimal differences in fasting compared with non-fasting cholesterol levels in the general population.
From a practical standpoint, non-fasting lipid assessments benefit individuals with diabetes as they may reduce the risk of hypoglycaemia from fasting. It also may improve patient adherence and reduce laboratory burden due to increased testing occurring in the morning.
- INCREASE DIETARY POTASSIUM TO REDUCE BLOOD PRESSURE
This recommendation is based on several systematic reviews and meta-analyses that demonstrated a consistent association between increased potassium intake and BP reduction. The change in lowered blood pressure appeared to be greatest in those who consumed the greatest amount of salt.
Potassium can be obtained through diet or dietary supplements, however diet is the preferred method because individuals gain the additional nutritional benefits of the recommended foods. Foods containing higher potassium include fresh fruits, vegetables and legumes such as bananas, tomatoes, broccoli, cantaloupe, sweet potato and brussel sprouts.
The recommendation for increased potassium should be used with caution for those at risk of hyperkalemia. This includes those with impaired urinary potassium excretion as a result of renal failure or those using medications that can cause hyperkalemia such as renin-angiotensin-aldosterone inhibitors, trimethoprim and sulfamethoxazole, amiloride, or triamterene.
- PHARMACOTHERAPY: A BETA-BLOCKER OR CALCIUM CHANNEL BLOCKER(CCB) MAY BE CONSIDERED FOR INITIAL THERAPY IN PATIENTS WITH STABLE ANGINA, BUT WITHOUT PREVIOUS HEART FAILURE, MYOCARDIAL INFARCTION OR CORONARY ARTERY BYPASS SURGERY.
This recommendation is based on multiple studies supporting the efficacy of beta-blockers and CCBs in preventing major adverse cardiovascular events in patients with chronic, stable coronary disease. It is also consistent with the recent Canadian Cardiovascular Society guidelines2.
5.TARGETS: FOR HIGH-RISK PATIENTS NEW GOAL IS TO HAVE SBP ≤ 120mm Hg.
High risk patients include:
- Clinical or sub-clinical cardiovascular disease
- Chronic kidney disease
- Estimated 10-year global cardiovascular risk >15%
- Age ≥ 75 years
This information was based on the findings from the Systolic Blood Pressure Intervention Trial (SPRINT). Since this study excluded people with diabetes, the current blood pressure targets of <130/80mm Hg still apply to this population.
Hypertension Canada’s 2016 CHEP guidelines were published in the Canadian Journal of Cardiology4 (http://www.onlinecjc.ca/article/S0828-282X(16)00192-6/pdf). You can also find the guidelines and tools at www.hypertension.ca.
- Arch Intern Med. 2012;172(22):1707-1710
- Can J Aug 2014 30(8):837-849
- N Eng J Med. 2015; 373: 2103-16
- Can J May 2016 32(5):569-588