Skip navigation
Link to Back issues listing | Back Issue Listing with content Index | Subject Index

Preventing hypertension

Benefits of living well
Strategies for primary prevention
Documented efficacy
Lifestyle modifications for primary prevention of hypertension
Comment

Bandolier used to say about itself that it was not a destination, but a signpost for good evidence. That is still true, but sometimes it likes to point out where collections of good evidence can be found. Advice about the primary prevention of hypertension [1] is one such collection, impossible to summarise, but an invaluable tool to remind ourselves that raised blood pressure is frequently preventable if individuals do some simple things.

Benefits of living well

The Framingham study suggested that if we lived for a very long time, then hypertension will get about 90% of us, and about one person in two over the age of 60 years has hypertension. But hypertension is just one of a number of modifiable lifestyle factors that affect risk. Bandolier's Internet healthy living pages have collected studies that link healthy living with longer life in British men and American women.

Large cohort studies in over 350,000 young and middle-aged men and women have indicated people with low cardiovascular risk factors (serum cholesterol below 5.2 mmol/L, BP below 120/80 mmHg, no current cigarette smoking) have 70-85% lower mortality from cardiovascular disease and 40-60% lower mortality from all causes compared with those who have one of these three risk factors. This translates into an additional 6-10 years of life.

Strategies for primary prevention

The document recommends two. One is a population-based strategy to try and reduce the average blood pressure. Table 1 shows the benefits of small blood pressure reductions in the population.

Table 1: Benefits of small blood pressure reductions in the population

Percent reduction in mortality

Reduction in BP
mmHg

Stroke

CHD

Total

2 6 4 3
3 8 5 4
5 14 9 7

The second strategy is a more intensive targeted approach aimed at achieving greater reduction in blood pressure in those most likely to develop hypertension. High risk groups include those with a high normal blood pressure, with a family history of hypertension, of black ancestry, who are overweight, have a sedentary lifestyle, who have too much sodium or too little potassium in their diet, or who drink too much.

Documented efficacy

There are a number of interventions with well-documented efficacy in lowering blood pressure. They are simple to list, as below. They are more difficult to deliver, especially if low sodium, high potassium foods are more expensive than those low in potassium but rich in salt, sugar, or fat.


Lifestyle modifications for primary prevention of hypertension

  1. Maintain normal body weight for adults (body mass index 18.5 to 24.9 kg/sq metre)
  2. Reduce dietary sodium intake to no more than 100 mmol per day (about six grams of sodium chloride or 2.4 grams of sodium per day)
  3. Engage in regular aerobic physical activity such as brisk walking (at least 30 minutes per day, most days of the week)
  4. Limit daily alcohol consumption to no more than 30 mL ethanol for men and no more than 15 mL for women and lighter weight persons [20 mL ethanol is equivalent to a pint and a half of beer, half a bottle of wine, or 60 mL of average strength spirits]
  5. Maintain adequate intake of dietary potassium (more than 90 mmol or 3.5 grams per day)
  6. Have a diet rich in fruits and vegetables and in low-fat dairy products with a reduced content of saturated and total fat

Comment

This document is well written, and thorough. It is not a scientific paper filled with statistics that stick for a moment, but a treatise filled with words and concepts that stick for a long time. The numbers included are there to illuminate and emphasise the importance of what is being related.

Bandolier often finds blood pressure a bit boring, but it is anything but boring for people starting new antihypertensive treatments. It is rarely pleasant, which is why so many change their medicines in the first few months (Figure 1).

Figure 1: Newly-treated antihypertensives



Reference:

  1. PK Whelton et al. Primary prevention of hypertension. Clinical and public health advisory from the National High Blood Pressure Education Program. JAMA 2002 288: 1882-1888.
previous or next story in this issue