The link between blood pressure and the kidneys
The relationship between the kidneys and blood pressure is complex. The kidneys play a role in controlling blood pressure, but high blood pressure increases the risk of chronic kidney disease (CKD).
Often, kidney disease does not appear on its own – frequently, people are living with other health conditions such as high blood pressure or diabetes. People with high blood pressure (and those with diabetes) should have their kidneys tested once a year.
The heart and kidneys work together to maintain healthy blood circulation. The heart pumps a continuous supply of oxygenated blood around the body, whilst the kidneys filter the blood and extract waste products as urine. The kidneys receive nearly 25% of the blood pumped out of the heart every minute.
The kidneys also control the amount of salt and water in the bloodstream and by sending chemical messengers (hormones), cause arteries to control blood pressure.
What happens when things go wrong?
If blood pressure is too high, the heart may stop pumping efficiently (‘heart failure’). This reduces the blood supply to the kidneys, causing them to retain salt and water and send signals to increase the blood pressure even more.
High blood pressure can narrow the kidney blood vessels, which eventually damages them. The filters in the kidneys (called ‘glomeruli’) stop working efficiently, leading to a progressive fall in kidney function. Kidney damage also causes increased production of the blood pressure controlling hormones, leading to high blood pressure.
How do we detect kidney disease?
The urine albumin-to-creatinine ratio (uACR) test specifically measures the amount of albumin compared to creatinine in the urine. The presence of albumin can increase when the filtration barrier is damaged, so can be an early indicator of kidney damage.
Dr Kevin Fernando, a GP from Scotland, created this video with Kidney Research UK explaining what uACR tests are, and why they are so important for the early detection and management of kidney disease, allowing healthcare professionals to implement preventive measures to slow the progression of kidney disease.
What can you do next?
If you have high blood pressure, you can ask your doctor about getting a uACR test to check your kidney health. You can take our quick and easy health check, to see if you are at risk of kidney disease. It only takes two minutes, and we will send you your results straight away.
Dr Zoe Markham-Lee, Research Development and Engagement manager, Multiple health conditions team, Kidney Research UK.
Information about Kidney Research UK
Kidney Research UK is the leading charity in the UK focused on funding research into the prevention, treatment and management of kidney disease. We work with clinicians and scientists across the UK, funding and facilitating research into all areas of kidney disease and we collaborate with partners across the public, private and third sectors. We lobby governments and decision makers to change policy and practice to ensure that the estimated 7.2 million people living with kidney disease in the UK have access to the most effective care and treatment, and to make kidney disease a priority. Enquires: enquiries@kidneyresearchuk.org
Registered charity no. 252892. Scottish charity no. SC039245.
For more information about kidney health visit www.kidneyresearchuk.org
