A few months ago Terenteva et al. published their research findings on the effect of acupuncture in a group of middle-aged individuals with hypertension. Forty five adults with hypertension were randomly assigned to either an acupuncture group or a control group. The acupuncture group received 3 sessions of acupuncture per week for 8 weeks. The following points were needled bilaterally for 20 mins: St36, St37, Pc5, Pc6, Liv3, Sp4, and LI11.
The researchers found that acupuncture “resulted in beneficial reductions of aortic hemodynamics and arterial stiffness”. “Acupuncture decreased brachial systolic blood pressure (SBP) and diastolic blood pressure (DBP) by approximately 10 and 6 mmHg, respectively.” It also reduced aortic SBP by 10 mmHg. Although these effects seem small, they can decrease cardiovascular risk by over 30%.
The mechanisms behind the effects are thought to come from an increase in secretion of vasodilators (nitric oxide) and a decrease in secretion of vasoconstrictors (endothelin-1, angiotensin II). Modulation of the autonomic nervous system by decreasing sympathetic activity may also play a part.
A recent study published in Medical Acupuncture has shown that electroacupuncture can significantly reduce systolic and diastolic blood pressure in hypertensive subjects. After the treatment, plasma levels of norepinephrine, renin and aldosterone were all significantly decreased and this is thought to be related to the beneficial effects of the electroacupuncture.
Last week we discovered that exercise is very effective at decreasing high blood pressure but what else can help? For those with hypertension, you’ll be relieved to hear that there are several things you can do to decrease your blood pressure and cut down the risks of heart disease and stroke.
- Weight loss. Losing 8kg can decrease your systolic blood pressure (SBP) by 8.5mm Hg and decrease your diastolic blood pressure (DBP) by 6.5mm Hg. A man’s waist circumference should be less than 102cm (90cm for asian men) and a women’s should be less than 88cm (80cm for asian women).
- Diet. A small reduction in sodium intake can lower blood pressure by 8-10mm Hg. Sodium intake should be restricted to 1500-2300mg in those with hypertension. According to the Mayo Clinic, the DASH (Dietary Approaches to Stop Hypertension) diet can reduce blood pressure by up to 14mm Hg. The DASH diet is rich in whole grains, fruits, vegetables and low-fat dairy products and low in saturated fat and cholesterol.
- Alcohol. In small amounts alcohol can actually be beneficial for the cardiovascular system but the protective effect is lost if you drink too much. The NHS recommends that “men should not regularly drink more than three to four units a day and women should not regularly drink more than two to three units a day”. Check out this unit calculator if you’re wondering exactly how much a unit is.
- Smoking and second-hand smoke. Smoking can elevate your blood pressure by about 10mm Hg for up to an hour after smoking.
- Caffeine. Caffeine has been found to increase blood pressure temporarily but the long-term effects are still unknown. The Mayo Clinic recommend that you drink no more than 2 cups of coffee a day whereas the NHS recommend drinking no more than 4 cups a day. I guess it depends on the type of coffee you’re drinking!
- Stress. Stress and anxiety can temporarily increase blood pressure so relaaaaax! Yeah, I know, easier said than done…It helps if you can identify the cause and then take some steps to curtail or eliminate it. Breathing exercises, meditation, yoga, exercise, CBT, counselling, etc may help as well.
Remember to check your blood pressure regularly to see how well you’re doing and why not enrol family and friends to offer support and make sure that you stick to the programme!
Blood pressure is the pressure exerted by the blood on the arteries and is measured in millimetres of mercury (mm Hg). There are two measures of blood pressure: the systolic blood pressure (SBP) is taken when the heart contracts and the diastolic blood pressure (DBP) is taken when the heart is relaxed. That’s why the systolic pressure is higher than the diastolic pressure. Blood pressure is considered high when it exceeds 140/90mm Hg and optimal blood pressure is 120/80mm Hg. High blood pressure or hypertension, as it’s also known, is a ‘silent killer’. ‘Silent’ because there are no signs unless it’s extremely high and ‘killer’ because it dramatically increases the risk of stroke, heart disease and kidney disease. Alarmingly, over 25% of adults in the UK have hypertension and that figure increases to more than 50% in those older than 60.
I was recently challenged by a client to provide evidence that exercise decreases high blood pressure. I think his exact words were…”where’s the evidence?” At first the question surprised me, but I soon realised he had a valid point. Why embark on a gruelling exercise programme without proof that it will actually fulfill the desired purpose?
So, here’s the evidence:
- Exercise decreases blood pressure in a staggering 75% of people with hypertension. On average, SBP decreases by 11mm Hg and DBP decreases by 8mm Hg. Now, if you’re thinking that those figures aren’t worth the effort…think again! The risks associated with hypertension are continuous. That means that with each 2mm Hg rise in SBP there’s an associated 7% increase in mortality from heart disease and 10% increase in mortality from stroke. So exercise alone can decrease your risks of dying from heart disease by just under 40% and decrease your risks of dying from stroke by 55%! Worth the effort?
- All guidelines (NHS, National Institute for Health and Clinical Excellence, American College of Sports Medicine, Canadian Hypertension Education Program, Mayo Clinic, etc) include exercise as a cornerstone in the prevention, treatment and management of hypertension.
Now that we know exercise works, here are some specific guidelines on how to go about it:
- Exercise should be undertaken on most days of the week and can include activities like gardening, household chores, walking, etc
- Perform primarily endurance exercise supplemented by some resistance work
- It should last 30mins a day (this can be continuous or accumulated over the day)
- The intensity should be 40-60% of reserve heart rate (low to moderate intensity exercise is as, if not more, beneficial as high intensity exercise)
What are you waiting for? Jump on that bike! Actually, before you jump on that bike, make sure you get permission from the owner and check with your GP as well. Next week, even more ways to help decrease blood pressure…