Reduce Sitting Time to Lower Blood Pressure

Dr JoAnn Manson comments on the significance of a randomized trial showing the benefits of reduced sitting time in older adults.
www.medscape.com/viewarticle/...
-- TRANSCRIPT --
JoAnn E. Manson, MD, DrPH: Hello. This is Dr JoAnn Manson, professor of medicine at Harvard Medical School and Brigham and Women's Hospital. I'd like to talk with you about a recent randomized trial to reduce sitting time and lower blood pressure in older adults: the Healthy Aging Resources to Thrive (HART) study published in JAMA Network Open.
We know that reducing cardiometabolic risk in older adults is very important, and there is perhaps no more promising target than sitting time, because we're a sedentary society. Among older adults, on average, more than 70% of time is spent sitting during our waking hours. Observational studies suggest that longer sitting time is associated with increased risk for cardiovascular disease, type 2 diabetes, and all-cause mortality. But those studies can't prove a cause-and-effect relationship because many chronic medical conditions are associated with more sitting time. So a randomized trial is important.
The researchers undertook a pragmatic clinical trial at Kaiser Permanente Washington State. The trial was primarily conducted during the pandemic and included 283 adults with a median age of 68. All had a body mass index above 30, and 52% had a diagnosis of hypertension, most of whom were treated with antihypertensive medications. The trial had an intervention group that received health coaching with at least ten contacts over 6 months for the purpose of reducing sitting time, breaking up bouts of sitting, and increasing standing time. The intervention group also received a standing desk and a fitness tracker to prompt breaking up sitting time.
The control group was an attention control group that also received ten contacts by phone, but this was not focused at all on physical activity or sitting time but rather on general healthy living goals.
Sitting time and physical activity were monitored by accelerometer. At 3 and 6 months, blood pressure was measured by an Omron device.
This randomized trial did show a reduction in sitting time at 3 and 6 months; a 31-minute reduction at both time points, with P .01 at both times; and a significant 3.5 mm Hg reduction in the systolic blood pressure at 6 months was seen in both men and women. Women also had a significant reduction in diastolic blood pressure levels.
The randomized trial showed a reduction in sitting time and in systolic blood pressure. You may be thinking, That is a modest reduction in systolic blood pressure, but the co-authors provide context that increasing aerobic exercise, which may be more challenging for older adults with chronic medical conditions, has led to a 4-mm reduction in systolic blood pressure (not much different), and the DASH diet results in a 5-mm Hg reduction. Even antihypertensive medications in many trials achieves only a 6-7-mm Hg reduction in systolic blood pressure.
We do need larger trials to try to replicate these findings. We also need more intensive interventions that could reduce sitting time by 45-60 minutes a day, which may be feasible based on other evidence. Based on the current evidence, recommending to our patients to reduce sitting time and break up bouts of sitting should be considered, because it may lower blood pressure and end up improving our patients' health. Thank you so much for your attention.
Transcript in its entirety can be found by clicking here:
www.medscape.com/viewarticle/...