New Blood Pressure Guidelines

Until recently high blood pressure was defined as blood pressure (BP) persistently above 140 mm Hg systolic or 90 mm Hg diastolic, but according to the 2017 hypertension guideline from a joint task force by the American College of Cardiology (ACC) and the American Heart Association (AHA), based on a review of almost 1,000 studies redefined high BP as readings persistently above 130 over 80 mm Hg which is now defined as hypertension. The new guideline is meant to prevent strokes, heart attacks, heart and kidney failure through lifestyle changes such as eating a healthy diet, exercising, reducing salt intake, loosing weight if overweight and taking antihypertensive medications if needed.

The ACC/AHA guideline provides four categories of BP, ranging from normal to stage II hypertension, as shown in the image above.  The guidelines, which were published in the Journal of the American College of Cardiology, prescribe exactly how blood pressure should checked.  Physicians and nurses are urged to let patients rest five minutes first and then to average at least two readings over two separate visits.  Meanwhile, patients are urged to take regular readings at home, with a device checked out by their health care providers.  The four categories are based on average BP measurements and for individuals with an abnormal systolic BP and diastolic BP, the designation should go to the higher category. To confirm a new diagnosis of hypertension, an out-of-office in the patient’s house confirmation of elevated BP is strongly suggested as the “white coat” high BP can wrongly categorize someone as having hypertension.

Based on the new guideline 46 percent of US adults, many of them under the age of 45, will now be considered hypertensive while under the previous guideline, 32 percent of US adults had hypertension.

Walking may slow Memory loss

According to a study by Morris et al published in PLoS One some patients with early stage Alzheimer’s disease may slow their memory loss with frequent brisk walks.

The authors conducted a 26-week trial comparing the effects of 150 minutes per week of aerobic exercise vs. non-aerobic stretching and toning in patients with early Alzheimer’s (AD). A total of 76 older adults with early AD (mean age 73) were enrolled, 68 of who completed the study.  Target heart rate (HR) zones were gradually increased from 40–55% to 60–75% of HR reserve based on resting and peak HR during cardiorespiratory fitness testing.

Neuropsychological tests and cardiorespiratory fitness testing and brain MRI were used to monitor fitness and analyze memory improvement or lack thereof.

One of the groups began a brisk walking program, while the second control group began stretching and toning classes designed not to increase their aerobic endurance.  While to some of the walkers thinking and remembering improved, toning did not slowed the progression of their disease.

Researchers concluded that aerobic exercise such as brisk walking had improved the ability of AD patients to remember and think and had reduced hippocampal atrophy suggesting that cardiorespiratory fitness may be important in brain functions.

Dementia declining among American seniors

A study by Langa et al published in JAMA Internal Medicine, reveals that the dementia rate in Americans 65 and older fell over the past 12 years.

The authors used data from the Health and Retirement Study (HRS) of individuals in the United States 65 years or older from the 2000 (n = 10 546) and 2012 (n = 10 511) waves of the HRS.

In this study of more than 21 000 US adults 65 years or older, dementia prevalence declined significantly, from 11.6% in 2000 to 8.8% in 2012.  Interestingly a previous post dated April 2016 reported on a study publishedin NEJM that found a decline in the incidence of dementia in the Framingham Hearth Study.

The study subjects 56% of which were females had an average age of 75.0 years in 2000 and 74.8 years in 2012. Dementia prevalence among those 65 years or older decreased from 11.6% in 2000 to 8.8%. More years of education was associated with a lower risk for dementia, and average years of education increased significantly from 11.8 years to 12.7 between 2000 and 2012.  An unexpected finding was that being overweight was also associated with a 30% decreased risk of dementia.  The decline in dementia prevalence occurred even though there was a significant age- and sex-adjusted increase between years in the cardiovascular risk profile (eg, prevalence of hypertension, diabetes, and obesity) among older US adults.

The authors concluded that the prevalence of dementia in the United States declined significantly between 2000 and 2012.