Physicians at Queen Mary University of London and Barts Hospital, and Cambridge University Hospital in England, have led research using a new type of CT scan to light up tiny nodules in a hormone gland and cure high blood pressure by their removal. The nodules are discovered in 1-in-20 people with high blood pressure.
Published in Nature Medicine, the research solves a 60-year problem of how to detect the hormone producing nodules without a difficult catheter study that is available in only a handful of hospitals, and often fails. The research also found that, when combined with a urine test, the scan detects a group of patients who come off all their blood pressure medicines after treatment.
Moreover, 128 people participated in the study of a new scan after doctors found that their hypertension, or high blood pressure, was caused by a steroid hormone, aldosterone. The scan found that in two-thirds of patients with elevated aldosterone secretion, this is coming from a benign nodule in just one of the adrenal glands, which can then be safely removed. The scan uses a very short-acting dose of metomidate, a radioactive dye that sticks only to the aldosterone-producing nodule.
The scan was as accurate as the old catheter test, but quick, painless, and technically successful in every patient. Until now, the catheter test was unable to predict which patients would be completely cured of hypertension by surgical removal of the gland. By contrast, the combination of a “hot nodule” on the scan and urine steroid test detected 18 of the 24 patients who achieved a normal blood pressure off all their drugs.
“These aldosterone-producing nodules are very small and easily overlooked on a regular CT scan,” says Morris Brown, co-senior author of the study and professor of endocrine hypertension at Queen Mary University of London. “When they glow for a few minutes after our injection, they are revealed as the obvious cause of hypertension, which can often then be cured. Until now, 99% are never diagnosed because of the difficulty and unavailability of tests. Hopefully this is about to change.”
William Drake, co-senior author of the study and professor of clinical endocrinology at Queen Mary University of London, adds: “This study was the result of years of hard work and collaboration between centers across the U.K. Much of the ‘on-the-ground’ energy and drive came from the talented research fellows who, in addition to doing this innovative work, gave selflessly of their time and energy during the national pandemic emergency. The future of research in this area is in very safe hands.”