Innovative method identifies patients who fail to take their blood pressure lowering medications

Researchers in MFT’s Clinical Biochemistry Department, in collaboration with University of Manchester Division of Cardiovascular Sciences and Manchester Molecular Pathology Innovation Centre (MMPathIC), have developed an in-house urine test to screen for non-adherence to antihypertensive medications. The local Clinical Biochemistry Department is the first to offer this test to patients and clinicians in the North West region of England.

In the UK, high blood pressure (hypertension) is the third biggest risk factor for all disease (after smoking and poor diet) and costs the NHS over £2.1 billion every year.  Although treatment for hypertension is proven to be effective, target blood pressures are only achieved in 40-50% of patients. This is largely caused by high numbers of patients not taking their medication correctly, if at all, which is known as non-adherence. Non-adherence is believed to be influenced by the fact that patients with hypertension rarely have noticeable symptoms. Despite a pervasive problem of non-adherence to ant-hypertensive medication, the associated health risks for patients with hypertension remains high.

Developing the test locally

Previously routine clinical laboratory services for urine anti-hypertensive screening in the UK was limited to two centres, neither of which are in the North West. To address this, Maciej Tomaszewski Professor of Cardiovascular Medicine at The University of Manchester) collaborated with Ed Hinchliffe (Principal Clinical Biochemist at Manchester University NHS Foundation Trust) to develop an in-house method for urine anti-hypertensive screening in the MFT Clinical Biochemistry Department. The project was supported by The University’s Manchester Molecular Pathology Innovation Centre (MMPathIC) who provided funding, which enabled development and validation of the new test.  

The test utilises High Performance Liquid Chromatography, coupled with High Resolution Accurate Mass Mass-Spectrometry (HRAM-MS) and represents the first detailed application of urine anti-hypertensive screening utilising this analytical platform. This highly sensitive and specific test detects the presence of all commonly prescribed anti-hypertensives in a single spot-urine sample and has been instrumental in revealing alarmingly high rates of non-adherence in the region.

Why screen urine for anti-hypertensive drugs?

Screening for anti-hypertensive drugs in urine has been demonstrated to be a useful aid in identifying patients with uncontrolled hypertension who fail to take their medication as prescribed. By identifying these patients, doctors can provide information on the results of their adherence urine analysis, combined with targeting the main reason for non-adherence. This is a major step forward in improving the long-term clinical outcomes for patients who have been identified as non-adherent, as a persistent elevation of blood pressure leads to a significantly higher risk of stroke, heart attack, heart failure, kidney damage, and death. Ultimately, identifying non-adherence will lead to an improvement in blood pressure control, adherence, and a reduction in healthcare costs.

What does this mean for Manchester and the region?

Since October 2018, this method for anti-hypertensive screening in urine has been embedded into routine clinical service at MFT. This means that the Clinical Biochemistry Department is in an important position to provide referral services for other UK clinical laboratories and offer this test to hospitals and practices in the North-West region of England.

Access to the new diagnostic test will transform the way we manage hypertension and resistant hypertension at MFT and across Greater Manchester

Professor Tomaszewski said: “Access to the new diagnostic test will transform the way we manage hypertension and resistant hypertension locally at MFT and across Greater Manchester. The test offers a more stratified approach to both diagnosis and therapy of high blood pressure and will benefit patients, doctors and the healthcare system”.

Professor Tomaszewski’s team’s research also formed the basis of a successful application to the British Heart Foundation in 2017. The team was awarded £754K to carry out a three year clinical study to assess whether, utilising the results of the urine test, a simple five-step intervention can encourage people to take their blood pressure medication properly. This research will show if this simple intervention can encourage people to take their anti-hypertensive medications on a regular basis and lead to an improvement in blood pressure.  

MMPathIC continue to be involved through leading the health economic analysis for the project; work which will establish whether the intervention can make financial savings for the NHS.