The CBS Evening News (9/28/11, story 4, 2:30, Pelley) reported, “A study out today suggests millions more Americans may be at risk of stroke” because of mild elevations of blood pressure (BP).
NBC Nightly News (9/28/11) reported that research published online in Neurology suggests that “a blood pressure reading that’s just below normal could still point to a higher risk.”
USA Today reports that individuals “whose blood pressure was almost above normal — known as pre-hypertension — were 55% more likely to have a stroke compared to people with normal blood pressure, according to an analysis of 518,520 adults involved in 12 studies on blood pressure and stroke occurrence.” Prehypertension refers to readings of 120-139/80-89
The HealthDay reports, “When the researchers split the people with prehypertension into two groups — those at the lower end of the prehypertensive range and those at the upper end — they found those in the upper range (130 to 139 mmHg systolic and 85 to 89 mmHg diastolic) had a 79 percent increased risk of stroke.”
Tropicana Forum Medical Commentary:
High blood pressure (hypertension) is officially diagnosed when someone has recurrent readings above 140/90. (There are circumstances when your doctor might choose a lower “normal” reading.) A single high measurement at a drug store or doctor’s office does not mean that one has hypertension. Multiple readings are needed for the diagnosis. Note that the top number is called “systolic” while the bottom number is “diastolic.”
I suggest that those at risk obtain a good home BP device. Ask your pharmacist and make sure that the cuff size is appropriate for your arm circumference. Then record your BP a couple of times per day, varying the times and keeping a written record with notes documenting time of day and circumstances (such as relaxed watching TV, an argument /stress, a big meal, after exercise or a salt load, lack of sleep, or alcohol prior to the reading). Then review the readings with your doctor. Sometimes clarification can be obtained with a 24 hour BP monitor which I think is a vastly underused diagnostic tool.
Pre-hypertension (120-139/80-89) is technically not hypertension, but it is a risk factor for hypertension and should be treated with life-style changes such as stress modification, weight reduction, salt reduction, and exercise. Pre-hypertension (the higher type at 135-139/85-89) is associated with increased stroke risk, although there is no evidence to say that medication should be used for this. Your doctor has to exercise his best judgement here by weighing all your cardiac risk factors. The lower range of 120-135/80-85 is not proven to be risky.
Two related issues include isolated systolic hypertension (ISH) and “white coat syndrome.”
Isolated systolic hypertension (ISH) is when only your systolic BP is consistently above 140 mm Hg while your diastolic is normal. It used to be thought that ISH was harmless, but it is risky and should be treated. Even those who have intermittent elevations (spikes) of systolic BP probably should be treated.
“White coat hypertension” (WCH) is when your BP is high at the doctor’s office, but not at home. This often ties into adrenaline surges that occur when someone is stressed. You can help with the diagnosis by using home readings and see how your BP responds to an argument or other stressful circumstances. WCH should also, in my opinion, be treated, and drugs, especially beta blockers, are often needed.
I have to stop typing now. Eileen is fussing about something, and I have to go check my blood pressure.
Paul Goldfinger, MD, FACC