An intensive, four-year blood pressure intervention significantly reduced the risk of dementia in adults with high blood pressure compared with those who received usual care, according to a study reported today as Late-Breaking Science at the American Heart Association’s Scientific Sessions 2023. Meeting, Nov. 11-13, in Philadelphia, is a major global exchange of the latest scientific advances, research and evidence-based clinical practice updates in cardiovascular science.
In the absence of curative treatment, primary prevention of dementia by reducing risk factors has become a public health priority. Previous observational studies have shown that people with untreated hypertension have a 42% increased risk of dementia compared to healthy adults, while people with treated hypertension have no significant increased risk of dementia compared to healthy adults.”
Jiang He, MD, PhD, FAHA, is professor of epidemiology and medicine and director of the Translational Science Institute at Tulane University in New Orleans.
Researchers evaluated the effectiveness of lowering blood pressure on dementia risk in people with high blood pressure. The study was conducted in 326 villages in rural China and included approximately 34,000 adults, 40 years of age or older, with crude blood pressure of 140/90 mm Hg or higher, or 130/80 mm Hg or higher for those at high risk of heart disease. or who are currently taking blood pressure medication.
Half of the villages were randomly assigned to a village doctor-led intensive blood pressure intervention strategy, and half of the villages were randomly assigned to usual care. Under the China New Rural Cooperative Medical Scheme (a health insurance plan that covers about 99% of rural residents for basic health care), usual care village patients receive their hypertension management from local village doctors or township hospital primary care physicians as part of regular health services. by doing Healthcare Services in China).
In the intervention group, trained rural doctors initiated and adjusted antihypertensive medication based on a simple treatment protocol aimed at achieving a target of systolic blood pressure less than 130 mm Hg and diastolic blood pressure less than 80 mm Hg under primary care supervision. The doctor’s step-by-step protocol for hypertension management included a treatment algorithm, drug selection, review of drug contraindications, and finally, dose adjustment strategies. They provide discounted and free blood pressure medication to patients and conduct health training on lifestyle changes, home blood pressure measurement and medication adherence.
At the end of the four-year study period, trained and certified neurologists, who were blinded to randomization assignment, administered the cognitive function assessment or screening. A final diagnosis of all-cause dementia or cognitive impairment, no dementia was made by a panel of expert judges, who were blinded to which intervention study participants were assigned. Cognitive impairment, a dementia is a broad classification for reduced cognitive functioning that does not meet criteria for dementia but exceeds normal, age-related cognitive decline.
Analysis showed that people in the intervention group showed significant improvements in blood pressure control and reduced dementia and cognitive impairment, compared to those who received usual care and no dementia. Additional Results:
- At 48 months the mean blood pressure in the intervention group was 128/73 mm Hg, compared with 148/81 mm Hg in the usual care group.
- On average, systolic blood pressure decreased by 22 mm Hg and diastolic blood pressure by 9 mm Hg in people in the intervention group compared with usual care.
- People in the intervention group had a 15% lower risk of dementia and a 16% lower risk of memory impairment than those in the usual care group.
- Serious adverse events, such as hospitalization and all-cause death, were less frequent in the intervention group.
“This is the first, large, randomized trial to demonstrate that lowering blood pressure is effective in reducing the risk of dementia in people with high blood pressure,” he said. “These findings emphasize the importance of widespread adoption of more intensive blood pressure control to reduce the global burden of dementia.”
Study Details and Background:
- The trial began in May 2018 and ended in March 2023.
- The mean age of study participants at enrollment was 63 years. 61% identified as female, and 39% identified as male; Researchers observed similar reductions in blood pressure and dementia risk in women and men.
Limitations of the study include that researchers did not assess participants’ cognitive function during baseline testing when they enrolled in the trial.
Future studies are needed to examine whether lowering blood pressure in adults at high risk of dementia without hypertension will reduce the risk of dementia.
The 2017 ACC/AHA Guidelines for the Prevention, Detection, Evaluation, and Management of Hypertension in Adults classify stage 1 hypertension as hypertension greater than or equal to 130/80 mm Hg and stage 2 hypertension. Numbers below are greater than or equal to 140/90 mm Hg.
According to the American Heart Association’s 2023 statistical update, nearly half of adults in the United States have high blood pressure. The estimated rate of dementia (alone, not including Alzheimer’s) among US adults age 65 and older was 10.5% in 2012, compared with 7.3% in men and 12.9% in women, according to the Aging, Population, and Memory Study, Long-Term Health and Retirement Study. A supplementary study.