Consistent with this burden, a recent new-user cohort reported a two-year cumulative incidence of hyponatremia of 3.83% for bendroflumethiazide (versus a calcium-channel blocker) and 3.51% for hydrochlorothiazide combined with a renin–angiotensin system inhibitor (versus a renin–angiotensin system inhibitor alone). This evidence concerns the gene REN and Hyponatremia.