Screening for hypertension in hospital to create a new diagnostic pathway
At a Glance
SHINE (Screening for Hypertension in the INpatient Environment) uses bespoke computer algorithms to screen patients admitted to hospitals in the Oxford University Hospitals NHS Foundation Trust for high blood pressure (hypertension). Patients will be followed-up to find out whether hospital blood pressure measurements accurately predict blood pressure measurements at home.
The aim of this research is to create a diagnostic pathway for the new diagnosis of high blood pressure among people admitted to hospital.
What is high blood pressure?
High blood pressure (also known as hypertension) is when the pressure of blood flowing through arteries in the body is higher than it should be. This makes the heart work harder to pump blood through the vessels around the body. High blood pressure is very common with 1 in 4 people in the UK affected. If not treated, it can cause serious long-term health problems. Blood pressure is measured using a device called a blood pressure cuff or monitor. This typically measures how hard the heart is pumping blood through one of the arteries in the arm. The measurement can be done in hospital, at the GP surgery or at home. An ‘ambulatory’ blood pressure test involves wearing a small portable blood pressure monitor which automatically measures the arm's blood pressure at set times throughout the day and night whilst a person carries out their regular day-to-day activities.
Why IS THIS important?
Hypertension is the leading risk factor for death worldwide. Untreated hypertension is associated with a progressive increase in blood pressure that can lead to serious long-term health issues such as heart attacks, strokes and vascular dementia. Patients admitted to hospital can have undiagnosed high blood pressure. However, previous research has shown that elevated blood pressure measurements in hospital are often not followed up, possibly due to health care professionals attributing high measurements in hospital to anxiety, pain or “white coat hypertension” (the presence of a health care professional at the time of measurement) and assuming that a person’s blood pressure will normalise once they go home. However, evidence suggests that patients with high blood pressure in hospital frequently continue to have high blood pressure once they are home.
Hospital detection and prompt treatment of hypertension offers an important opportunity to address this major cause of morbidity and mortality and improve the health of those affected.
In 2015, Oxford University Hospitals NHS Foundation Trust introduced the EPSRC/NIHR-funded System for Electronic Notification and Documentation (SEND). SEND links hospital bedside monitoring devices including blood pressure monitors, with a tablet computer for the accurate recording of vital observations of patients. SEND has monitored vital observations of more than 100,000 patients so far and links each patient’s observations with their Electronic Patient Record (EPR). This has paved the way for real-time and intelligent automated recognition of patients whose observations indicate they may be at increased risk of undiagnosed chronic disease, such as hypertension.
Using specially developed algorithms to search through records created by SEND, we will approach patients admitted to the John Radcliffe Hospital and ask if they are willing to wear a blood pressure monitor for 24 hours. This would be between 4 and 24 weeks after they have been discharged. The blood pressure monitor will be couriered to the participant's home where they will receive a video call from a researcher guiding them through the fitting procedure. At the beginning of the fitting appointment the participant will undergo a series of health checks to ensure ambulatory blood pressure monitoring is still appropriate for them. This includes performing a single lead ECG using a KardiaMobile device to check for the presence of atrial fibrillation. The KardiaMobile device instantly generates a report in the accompanying app and provides an automatic interpretation. The report will later be reviewed by a clinician.
We will ask the participant to carry out their normal daily activities whilst wearing the blood pressure monitor. After they have completed 24 hour ambulatory blood pressure testing we will compare their blood pressure measurements in hospital to their blood pressure measurements at home. Participants will be asked to keep in touch for a year after their discharge from hospital. During this time, they will be asked about their contact with health professionals such as their GP or practice nurse. If they see a GP or practice nurse, we will ask if they had their blood pressure checked and if they have started any treatment for high blood pressure.
We will use our findings to design a new diagnostic pathway. This will help health care professionals know what to do when someone has high blood pressure in hospital. It will also detail what should take place after the person is discharged from hospital.
SHINE is actively recruiting in Oxford University Hospitals NHS Trust.