The study, published in the journal Hypertension on October 1, compared more than 23,000 people with resistant hypertension with more than 24,000 people whose blood pressure was under control. Participants came from Iceland, the UK and the US. The researchers identified 24 genetic variants linked to resistant hypertension, about two-thirds of which were associated with hyperaldosteronism, or excess aldosterone, and low potassium levels.

Resistant hypertension is high blood pressure that stays uncontrolled despite treatment with several drugs. According to deCODE, the results indicate that aldosterone-blocking medication could help more patients than the 8.8% of affected Icelanders who currently receive it.

Vinicius Tragante, a scientist at Amgen deCODE genetics, said the findings help explain why some patients respond poorly to standard treatment.