Walking further and faster linked to reduced risk of cardiovascular events in people with high blood pressure

An analysis of over 36,000 people with high blood pressure has shown that taking more steps, even below the recommended daily target of 10,000 steps, and walking faster, is associated with a significant reduction in the risk of major problems of the heart and blood vessels, according to Medical Xpress.

The study, published in the European Journal of Preventive Cardiology, found that compared to a daily step count of 2,300 steps, every extra 1,000 steps was linked to a 17% reduction in the risk of developing a major adverse cardiovascular event (MACE), up to 10,000 steps. Additional steps above 10,000 were associated with a lower risk of stroke.

Approximately 1.28 billion people worldwide are living with high blood pressure, and it places them at increased risk of heart disease (49% increase), stroke (62% increase) and heart failure (77–89% increase). Until now, it has been unclear how much people with high blood pressure need to increase their physical activity in order to see a reduction in their risk of MACE.

Professor Emmanuel Stamatakis, Director of the Mackenzie Wearables Research Hub at the University of Sydney, Australia, who supervised the study, said, "This study is one of the first to demonstrate a dose-response relationship between daily step count and major problems of the heart and blood vessels.

"In a nutshell, we found that, if you live with high blood pressure, the more you walk with greater intensity, the lower your risk for future serious cardiovascular events.

"These findings support the message that any amount of physical activity is beneficial, even below the widely recommended daily target of 10,000 steps."

The study analyzed data obtained from 32,192 people who had enrolled in a sub-study of the UK Biobank study. They had been diagnosed with high blood pressure and agreed to wear an accelerometer on their wrist for seven consecutive days to measure how far and how fast they walked.

Data from the accelerometers was collected between 2013 and 2015. The average age was 64 and the participants were followed up for nearly eight years, providing the researchers with data for 283,001 person-years. During this time, 1,935 cases of heart problems or stroke occurred.

In addition to a 17% reduction in overall risk for every extra 1,000 steps a day, the researchers found a 22% reduction in heart failure, 9% reduction in risk of heart attack, and 24% reduction in risk of stroke. This means that every increase of 1,000 steps a day was associated with:

• an average reduction in the absolute risk of MACE of 31.5 events per 10,000 person-years

• an average reduction in the absolute risk of 7.2 heart failure events per 10,000 person-years

• an average reduction in the absolute risk of 9.9 myocardial infarctions (heart attacks) per 10,000 person-years

• an average reduction in the absolute risk of 10.4 strokes per 10,000 person-years.

The average (mean) intensity of the 30 minutes of fastest walking per day was 80 steps a minute and this was associated with a 30% reduced risk of MACE. There was no evidence of harm in people whose 30 minutes of fastest walking or running was over 130 steps a minute.

The researchers found similar results when they looked at 37,350 people without high blood pressure. Every 1,000-step increase in daily step count led to an average lower risk of MACE, heart failure, myocardial infarctions and stroke of 20.2%, 23.2%, 17.9%, and 24.6%, respectively.

Prof. Stamatakis said, "Our findings offer patients accessible and measurable targets for heart health, even below 10,000 steps daily. Clinicians should promote physical activity as standard care, especially in patients with high blood pressure. Our results can inform new, tailored public health recommendations for these patients. Future recommendations on walking in people with high blood pressure could consider promoting higher stepping intensity."

Strengths of the study include the large number of patients, the use of accelerometers to provide detailed information on numbers of steps and speed, and the use of data from national records in England, Wales and Scotland on deaths and causes of death.

Limitations include the fact that physical activity was measured only when people first joined the study and did not include any subsequent changes in behavior. In addition, the researchers point out that their findings can show only that there is an association between walking further and faster and better health outcomes, not that it causes these better outcomes.

However, they conducted extensive analyses to minimize the risk of what is called 'reverse causation' (in which, in this case, health problems could be causing both a reduction in physical activity and an increase in heart disease events).

Most UK Biobank participants are white, are less likely to be obese, to smoke or drink alcohol, and to be better educated, and so they may not be representative of the general UK population.