Hypertension remains a leading health concern. Our thought in management has been, as the authors in this research article point out, "the lower the better" in treating the approximately one in four people who have high blood pressure. 22 per cent of Canadians have high blood pressure but 17 per cent don't know they have it.  

The question remains - does the "lower is better" approach result in reduced risk for dangerous heart events?

In a study published in the June 16 JAMA Internal Medicine, researchers at Wake Forest Baptist Medical Center found that lowering systolic blood pressure below 120 does not appear to provide additional benefit for patients.

Systolic pressure is the top number in a standard blood pressure reading (e.g., 120/80).

This study found that treating to lower pressures doesn't provide any benefit to patients with regard to reducing risk of dangerous heart events like heart attack, heart failure and stroke. This calls into question the notion that lower is better.

Previous studies document  a progressive increase in heart disease risk as systolic blood pressure (SBP) is  above 115, but it was not known whether SBP lower than 120 in patients with hypertension lowered the risk of heart failure, stroke and heart attack.

4,480 participants from the Atherosclerosis Risk in Communities Study were followed for 21 years for development of a cardiovascular event. Measurements of BP were taken at baseline and at three-year intervals. BP was categorized as elevated (140 or greater), standard (120 -139) or low (less than 120).

The study findings were independent of baseline age, gender, diabetes status, body mass index, cholesterol level, smoking status and alcohol intake. A cardiovascular event was defined as

  • heart failure
  • ischemic stroke
  • heart attack
  • death related to coronary heart disease

The researchers found that among people with high blood pressure, once SBP is below 140, lowering it below 120 did not further reduce the risk of cardiovascular events.

The authors state that the study found that the optimal blood pressure range for people with hypertension is 120-139, which significantly reduces the risk of stroke, heart attack or heart failure.

The findings suggest that you don't need to go lower than that to have the benefits.

A large clinical trial under way called SPRINT should either confirm or refute the findings.

Sedentary behaviour & cancer risk

  • Sedentary behavior increases the risk of certain cancers
  • Physical inactivity has been linked with diabetes, obesity, and cardiovascular disease, but it can also increase the risk of certain cancers
  • To assess the relationship between TV viewing time, recreational sitting time, occupational sitting time, and total sitting time with the risk of various cancers, conducted a meta-analysis of 43 observational studies, including over 4 million individuals and 68,936 cancer cases.
  • Data in the individual studies had been obtained with self-administered questionnaires and through interviews.
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  • When the highest levels of sedentary behavior were compared to the lowest, the researchers found a statistically significantly higher risk for three types of cancer -colon, endometrial, and lung.
  • Moreover, the risk increased with each 2-hour increase in sitting time, 8 per cent for colon cancer, 10 per cent for endometrial cancer, and 6 per cent for lung cancer, although the last was borderline statistically significant.
  • The effect also seemed to be independent of physical activity suggesting that large amounts of time spent sitting can still be detrimental to those who are otherwise physically active.
  • TV viewing time showed the strongest relationship with colon and endometrial cancer, possibly because TV watching is often associated with drinking sweetened beverages, and eating junk foods.
  • Sedentariness has a detrimental impact on cancer even among physically active persons implies that limiting the time spent sedentary may play an important role in preventing cancer