High blood pressure is a common condition that may increase a person’s chances of developing dementia. Research is ongoing about the best ways to decrease the risk of dementia. A recent study found that among people with high blood pressure, drinking one-half to one cup of coffee or four to five cups of tea daily was associated with some of the lowest dementia risk. The study, published in Scientific Reports, examined how caffeine consumption related to dementia risk, using data from over 453,000 participants. The researchers observed that people with high blood pressure may be able to decrease their risk of developing dementia by consuming a certain amount of coffee or tea – one-half to one cup of coffee or four to five cups of tea daily. While more data is required, the results highlight another potential protective action step that may benefit people with high blood pressure.
People with high blood pressure can be at an increased risk for dementia. Hypertension is a well-established risk factor for dementia, including both vascular dementia and Alzheimer’s disease. High blood pressure can cause damage to the blood vessels in the brain, leading to reduced cerebral perfusion and microvascular damage, contributing to cognitive decline. Chronic hypertension may lead to the accumulation of small infarcts, white matter lesions, and disruption of the blood-brain barrier, increasing the risk of neurodegenerative processes. Hypertension is linked with other vascular risk factors, such as diabetes and hyperlipidemia, further increasing the risk of cognitive impairment.
A study examined the relationship between drinking coffee and tea and dementia risk using data from the U.K. Biobank and analyzing 453,913 participants, over half of whom had high blood pressure. Researchers excluded participants with dementia at baseline and secondary high blood pressure, and after adjusting for covariates, found that individuals with high blood pressure still had a greater risk for all-cause dementia, Alzheimer’s disease, and vascular dementia. The study found a J-shaped relationship between coffee and all-cause dementia among participants with high blood pressure, with participants who drank one-half to one cup of coffee daily having the lowest chances of developing all-cause dementia. There was a U-shaped association between drinking tea and risk for all-cause dementia among participants with high blood pressure, with participants who drank four to five cups of tea daily having the lowest risk.
The researchers identified a U-shaped association between drinking tea and coffee and dementia risk among participants with high blood pressure, with participants who had four to five cups of coffee and six or more cups of tea daily having the lowest chances of developing Alzheimer’s disease and all-cause dementia. There was no association between drinking tea or coffee and dementia among participants without high blood pressure. Different types of coffee consumed also seemed to have an effect, with ground coffee associated with the lowest risk of all-cause dementia and vascular dementia among all participants compared to decaf coffee. Additionally, there was a U-shaped association between caffeine intake and dementia risk among participants with high blood pressure. The researchers observed that finding a significant association between amounts of coffee and tea and dementia was more likely among participants with high blood pressure than among those without high blood pressure.
The study does have limitations, such as the U.K. Biobank not reflecting the general population and potential underestimations of dementia among participants. The study cannot establish a causal relationship between dementia and caffeine. More research is needed before implementing changes in clinical practice. Understanding the mechanisms behind the potential benefits of coffee and tea in preventing dementia, as well as emphasizing hypertension management, are crucial in developing future guidelines. The study reinforces the importance of addressing vascular risk factors in dementia prevention, particularly in middle-aged patients, and points towards possible benefits from coffee and tea as part of a balanced diet.
