New report outlines evidence for link between cardiovascular and brain health, and practical tips for reducing risk of dementia

A new report from the Global Council on Brain Health (GCBH) confirms that heart and brain health are connected, and that taking action to improve your cardiovascular health reduces the risk of cognitive decline and dementia. The Brain-Heart Connection summarises the strongest research on this topic and offers practical lifestyle tips people can take to protect their heart and brain health. We spoke to Prof Joanna Wardlaw, Group Leader at UK DRI at Edinburgh and expert contributor to the report, about the science and significance of the findings.

Cardiovascular risk factors, such as high blood pressure, high cholesterol, smoking and diabetes, are known to be harmful to the brain. The more risk factors a person has, the more likely they are to experience cognitive decline. However, there is strong evidence that reducing or treating these conditions lowers a person’s risk of cognitive decline and dementia, even if changes are made in their 70s or 80s.

The report outlines the positive action individuals can take to improve their heart and brain health, such as:

• Leading a physically active life
• Checking your blood pressure regularly and working with a health professional to lower it if it is too high 
• If you smoke, quit. If you don’t smoke, don’t start. Smoking in any form is bad for the heart and the brain
• Taking the time and steps to manage your stress effectively
• If you have diabetes or pre-diabetes, consulting with a health provider and nutritionist in order to help manage these conditions

In addition, helpful lifestyle tips and recommendations for health providers are included in the report, together with a discussion of the scientific evidence supporting these conclusions and gaps in current medical knowledge.

Prof Joanna Wardlaw, Group leader at UK DRI at Edinburgh, is an expert contributor to the report as she is investigating the effects of cerebrovascular disease on the brain in the fields of stroke and small vessel disease, including work on vascular risk factors and life course risk including early life exposures. Dr Wardlaw studies mechanisms of vascular brain injury to understand more about prevention and treatment. Based on this work, her team are running one of the few randomised clinical trials anywhere in the world that uses drugs to prevent vascular causes of dementia, known as the LACI trials. For more insight into the report, we sat down with Joanna for a Q&A.

What are the most recent and interesting discoveries linking the heart with brain health?

We have known for some time about major modifiable risk factors for dementia which include hypertension, diabetes and smoking. Furthermore these factors also cause heart diseases, for example ischaemic heart disease, many of which are associated with increased risk of dementia, partly by co-association and possibly through direct effects.

More recently, the importance of socioeconomic status, education and early life factors have been recognised as critical risk factors for both heart and brain vascular disease. A good diet, sufficient sleep and plenty of exercise are also essential to maintaining a healthy heart and, directly or by co-association, a healthy brain. There are epidemiological and mechanistic explanations for this, even though there is a limited amount of evidence from randomised clinical trials.

What are the main reasons why cardiovascular health has such a significant influence on brain health?

The brain is a highly metabolic organ that takes 20-25% of the cardiac output at rest – more during increased brain activity. It would be very strange if heart and brain disease were not closely linked.

The heart and brain are exposed to the same risk factors, and vessels in both organs share many features of diffuse disease including stiffening and breakdown of the vessel walls. Indirectly, there are downstream effects for the brain from heart disorders such an inadequate supply of blood to the energy ‘hungry’ brain. 

How important is an interdisciplinary approach in tackling neurodegenerative diseases?

This is exceptionally important due to the complexity of the brain. We should avoid seeing the blood vessels in isolation from the rest of the brain, and the brain in isolation from the rest of the body.

The brain should not be considered from the perspective of only one ‘ology’; I would never have tracked the importance of early life factors on vascular brain damage had I not known about epidemiology as well as stroke, cardiovascular disease, neurology, neuroscience, neuroimaging and the specifics of small vessel disease and dementia.

Read the full report, The Brain-Heart Connection, from GCBH and find out more about the work of Prof Joanna Wardlaw’s lab.

Article published: 24 February 2020