Intensive BP-lowering reduces dementia risk in patients with hypertension

Among Chinese patients with hypertension, a 48-month intensive blood pressure (BP) intervention programme significantly reduces the risk of developing dementia than usual care, according to a study presented at AHA 2023.

“In the absence of curative treatment, the primary prevention of dementia through risk factor for reduction, such as BP lowering, has become a public health priority,” said Prof Jiang He from Tulane University Translational Science Institute in New Orleans, Louisiana, US.

“Previous randomized controlled trials lacked sufficient duration or sample size and reported a nonsignificant reduction in dementia associated with antihypertensive treatment in patients with hypertension or a history of stroke,” he noted.

To assess the effectiveness of intensive BP intervention strategy in reducing the risk of all-cause dementia and cognitive impairment, the researchers conducted an open-label, blinded-endpoint, cluster-randomized trial involving 33,995 individuals (mean age 63 years, 61 percent female) with uncontrolled hypertension from 326 villages in China. Half of the villages received intervention with trained village doctors initiating antihypertensive medication using a simple protocol to achieve a BP goal of <130/80 mm Hg, with the supervision of the primary care physicians. The other half received usual care. They also provided free or discounted medication, health coaching, and assistance with home BP monitoring.

At 48 months, systolic BP significantly decreased from 157.0 to 127.6 mm Hg in the intervention group compared to a decrease from 155.4 to 147.7 mm Hg in the control group, with a net reduction of 22.0 mm Hg (p<0.0001).

Diastolic BP was also reduced from 87.9 to 72.6 mm Hg in the intervention group and from 87.2 to 81.0 mm Hg in the control group at 48 months. This resulted in a net reduction of 9.3 mm Hg (p<0.0001).

Taken together, 67.7 percent of the participants achieved the target BP of <130/80 mm Hg in the intervention group, while only 15.0 percent of those in the usual care group achieved this outcome.

In the primary outcome, patients who received intervention had a significantly lower rate of all-cause dementia compared with those who received usual care (1.12 percent vs 1.31 percent rate per year; relative risk [RR], 0.85; p=0.0035). [AHA 2023, abstract LBS.04]

Significantly lower rates of cognitive impairment alone (4.19 percent vs 5.02 percent; RR, 0.84) and the composite outcome of dementia or cognitive impairment (5.31 percent vs 6.34 percent; RR, 0.84) and dementia or deaths (3.04 percent vs 3.54 percent; RR, 0.86) were also observed in the intervention arm over the usual care arm (p<0.0001 for all).

Similarly, the rates of serious adverse events, including total mortality and hospitalization, were lower with intervention compared with usual care (9.16 percent vs 9.86 percent; p=0.0006).

Overall, the analysis showed that individuals in the intervention group had significant improvements in BP control as well as significantly reduced rates of all-cause dementia and cognitive impairment compared with those who received usual care.

“[In addition,] the effectiveness of BP reduction on all-cause dementia was consistent across subgroups based on age, sex, education, cigarette smoking, body mass index, systolic BP, and fasting plasma glucose at baseline,” He noted.

“This is the first, large, randomized trial to demonstrate that lowering BP is effective in reducing the risk of dementia in people with high BP,” He said in a press release. “These findings emphasize the importance of widespread adoption of more intensive BP control to reduce the global burden of dementia.”