130/80 BP is new high in 2017 hypertension guidelines
A blood pressure (BP) reading of 130/80 mm Hg or higher is the ‘new high’ in the latest AHA/ACC* hypertension guidelines, a threshold that is tighter than the JNC 7** cutpoint of 140/90 mm Hg for stage 1 hypertension in the general population. The change will mean more patients being labelled with hypertension.
“These are pragmatic decisions, the last time we changed the classification was in 1993. We moved the bar down because there’s convincing evidence that at stage 1, you’re already at double the risk for a heart attack or stroke. People should know that and they should be empowered to make a change and there’s evidence from non-drug and drug trials that going down below this level is beneficial,” said writing committee chairman Dr Paul K. Whelton from Tulane University School of Public Health and Tropical Medicine and School of Medicine in New Orleans, Louisiana, US.
The normal BP has not changed at <120 systolic and <80 diastolic. “When you get above that at 120-129 and <80 mm Hg, that’s already elevated BP and a signal that we should be concerned, so we recommend lifestyle changes. A BP of 130–139 systolic or 80–89 diastolic [previously called pre-hypertension], is already stage 1 hypertension in the new guidelines. Lastly, a BP of 140/90 and above is stage 2 hypertension.”
The last comprehensive guideline was by the JNC 7 in 2003. Whelton said the new definition of high BP makes nearly half of the US adult population hypertensive and a target of BP control strategies. “It doesn’t mean they need medication, but at a minimum it’s a yellow light that they need to lower their BP, mainly with non-drug approaches.”
How best to measure BP
The guidelines emphasize that to categorize BP levels, clinicians should have an accurate BP measurement taken in both arms and to use the arm that gives the higher BP for an average of ≥2 readings on ≥ 2 occasions. Out-of-office BP measurement is likewise recommended.
“What we get in the office is helpful, but it provides a very small window,” said Whelton.
For those with masked hypertension (normal BP in the clinic but high at home), their pattern of risk is similar to sustained hypertension. On the flip side, for those with white coat hypertension (high in office but normal outside), their risk pattern is very similar to the normotensive. “So, it’s important to get out-of-office BP to confirm office hypertension, recognize white coat or masked hypertension, and protect those with masked hypertension,” said Whelton. “These, together with the underlying CV risk, are important in making treatment decisions. Only then do we decide what to do – do we advise lifestyle change or lifestyle change with medication?”
Weight loss, the DASH (Dietary Approaches to Stop Hypertension) diet, sodium reduction (to 1,500 mg/day), and increased physical activity (at least 30 minutes of exercise thrice weekly) are recommended. Correcting the dietary aberrations and excessive alcohol intake are also part of the prevention and management strategies, either alone or in combination with a pharmacological regimen. When clinicians embark on therapy, particularly intensive therapy, it has to be done carefully. Adverse outcomes should be monitored, whether it be symptomatic, hypertension, or electrolyte imbalances. “We should be ready to adapt to the outcomes by changing drugs or modifying the dose,” he added.
BP targets in special populations
For adults with confirmed hypertension and known CVD or 10-year atherosclerotic CVD event risk of 10 percent or higher, a BP target of <130/80 mm Hg is recommended. For those with hypertension but without additional markers of increased CVD risk, a target of <130/80 mm Hg may be reasonable.
“In older adults with high BP, we know from several trials particularly from SPRINT that lowering their BP is very helpful and that you can do it effectively without commonly seeing major problems like hypotension, falls, and fractures. We recommend patients who are 65 or older or those at high cardiovascular risk to receive drug therapy.”
In adults at increased risk of heart failure (HF) and in those with hypertension and CKD, they should be treated to a goal of <130/80 mm Hg. In patients with diabetes and hypertension, antihypertensive treatment should be initiated at a BP of 130/80 or higher, with a treatment goal of <130/80. All first-line agents (ie, diuretics, ACE inhibitors, ARBs, and CCBs) are effective.
For pregnant hypertensive women, the goal of treatment is the prevention of severe hypertension and to prolong gestation to allow the foetus more time to mature before delivery. Transitioning to methyldopa, nifedipine, and/or labetalol is indicated. ACE inhibitors, ARBs, or direct renin inhibitors are contraindicated because of potential harm to the foetus.
The guideline is a collaborative effort of 11 health professional organizations after a 3-year review of over 900 published studies. It was released at AHA 2017 and published simultaneously in the Journal of the American College of Cardiology and the AHA journal Hypertension. [J Am Coll Cardiol 2017;doi:10.1016/j.jacc.2017.11.005; Hypertension 2017;doi: 2017;HYP.0000000000000065]
“This is a very rigorous guideline,” said Whelton. “We are more careful in defining hypertension and recommend more intensive treatment of hypertension. The bottom line is if we implement this, it will improve the cardiovascular health of most adults with high BP.”
In an accompanying editorial, Dr Philip Greenland from the Northwestern University’s Feinberg School of Medicine in Chicago, Illinois, US said a huge challenge for clinicians is how to translate these guidelines into clinical practice. Only half of patients classified as hypertensive under the previous guidelines had their BP controlled, and the proportion at the new goals will be even lower. This ups the pressure on clinicians to more effectively treat BP. [J