Common type of high blood pressure's cause and cure discovered

The cause is a tiny benign nodule, present in one-in-twenty people with hypertension. The nodule produces a hormone, aldosterone, that controls how much salt is in the body. The new discovery is a gene variant in some of these nodules which leads to a vast, but intermittent, over-production of the hormone.

The gene variant discovered today causes several problems which makes it hard for doctors to diagnose some patients with hypertension. Firstly, the variant affects a protein called CADM1 and stops cells in the body from ‘talking’ to each other and saying that it is time to stop making aldosterone. The fluctuating release of aldosterone throughout the day is also an issue for doctors, which at its peak causes salt overload and hypertension. This fluctuation explains why patients with the gene variant can elude diagnosis unless they happen to have blood tests at different times of day.

The researchers also discovered that this form of hypertension could be cured by unilateral adrenalectomy – removing one of the two adrenal glands. Following removal, previously severe hypertension despite treatment with multiple drugs disappeared, with no treatment required through many subsequent years of observation.

Fewer than 1% of people with hypertension caused by aldosterone are identified because aldosterone is not routinely measured as a possible cause. The researchers are recommending that aldosterone is measured through a 24-hour urine test rather than one-off blood measurements, which will discover more people living with hypertension but going undiagnosed.

Reference:

'Somatic mutations of CADM1 in aldosterone-producing adenomas and gap junction-dependent regulation of aldosterone production',Nature Genetics,DOI 10.1038/s41588-023-01403-