High blood pressure – known scientifically as hypertension – is where a person’s heart must work harder to push blood through blood vessels, putting strain on the heart. Type-2 diabetes is a condition in which a hormone called insulin (which breaks down blood sugar) can’t work properly, leading to high blood sugar levels.
Type-2 diabetes and hypertension are both associated with increased dementia risk, but there has been a gap in the research for people living with both conditions, known as co-morbidity. Now, a new study published in the journal Diabetes, Obesity and Metabolism has investigated the brain health of people living with both hypertension and type-2 diabetes.
The paper was authored by Dr Danielle Newby, a postdoctoral researcher from the University of Oxford with funding from the DPUK Discovery Award, and Dr Victoria Garfield, a research fellow from University College London. The duo analysed data from UK Biobank on almost 40,000 people who had either diabetes, hypertension, both conditions, or neither condition.
The data contained the medical records and self-reported diagnoses of people aged 40-69. The participants had also completed various cognitive tests, which measure thinking skills, and undergone different brain scans (known as neuroimaging techniques), giving the researchers a detailed measure of their brain health.
Dr Newby said: ‘We found that individuals with diabetes have poorer brain health and cognitive performance on a range of neuroimaging measures and cognitive tests. Those with both diabetes and hypertension have worse brain health and cognitive performance (particularly processing speed) compared to those without hypertension or diabetes or compared to people with only hypertension.’
Both type-2 diabetes and hypertension can be improved by introducing healthy lifestyle behaviours such as losing weight, not smoking and eating a balanced diet. The present study provides more evidence that supporting people with these conditions – especially those living with both hypertension and type-2 diabetes – is an effective way to improve brain health and reduce dementia risk.
Dr Newby concluded: ‘Our study suggests that prevention of both diabetes and hypertension may help delay changes in brain structure and cognitive decline, as well as reducing future dementia risk.’