Having hypertension is a significant risk factor for developing dementia. Only 25% of Americans with high blood pressure have it under control, a figure that drops further among Black and Hispanic individuals due to barriers in diagnosis and treatment.
Most research on reducing dementia risk through blood pressure control has focused on white participants, despite the disproportionately high risk among Black and Latino populations. The researchers of a new study aimed to bridge this knowledge gap by examining the effects of blood pressure control on dementia risk within these underrepresented groups.
Their findings suggest that lowering systolic blood pressure below the clinically safe threshold of 120 mmHg over time may slightly reduce an individual's risk of developing dementia, particularly among Black and Latino groups. The systolic blood pressure is the pressure in the arteries when the heart contracts.
"Despite the increase in hypertension rates, minoritized groups are less likely to benefit from blood pressure reduction interventions, through health policies or access to medicine. We hope that findings like these encourage policymakers and health practitioners to increase access to treatment for blood pressure control for these populations to reduce disparities in hypertension and, subsequently, in dementia rates," study senior and corresponding author Marcia Pescador Jimenez said in a news release.
The study included 6,814 participants from the Multi-Ethnic Study of Atherosclerosis, an ongoing research initiative led by the National Heart, Lung, and Blood Institute. Researchers investigated the effects of various interventions, including medication, dietary adjustments, and lifestyle changes, aimed at lowering blood pressure.
Over the 19-year study period, 8.8% of the participants developed dementia. Approximately half of the participants required interventions to reduce their systolic blood pressure below 140 mmHg, while 86% needed interventions to lower it below 120 mmHg.
"Compared to participants with no blood pressure-lowering interventions, each analysis found that blood pressure-lowering interventions among Latino and Black participants would have a slightly greater chance of lowering their risk of late-life dementia, compared to White participants," the news release stated.
However, the researchers noted a slightly adverse effect from blood pressure-lowering interventions among Chinese American participants. This may be due to the small sample size and fewer cases of dementia observed in this population within the study.
The researchers hope their findings will encourage further research into racial and ethnic disparities in effective hypertension control.
"Next, we plan to investigate the robustness of these results in other representative samples of minoritized populations, particularly in studies where dementia ascertainment is not different across racial and ethnic groups," Pescador Jimenez said.
