GLP-1 Receptor Agonists vs. MRAs in Resistant Hypertension: What a New Cohort Study Found

Resistant hypertension — blood pressure that stays uncontrolled despite three or more antihypertensive drug classes, typically including a diuretic — is disproportionately common in people with overweight or obesity. Current guidelines point to mineralocorticoid receptor antagonists (MRAs) such as spironolactone as the standard fourth-line addition. GLP-1 receptor agonists (GLP-1RAs), including semaglutide, are known to produce modest blood-pressure reductions alongside their metabolic effects, but until now there has been little direct comparative data on how they perform against MRAs specifically in this harder-to-treat population. A retrospective cohort study published in EClinicalMedicine set out to address that gap.

A large real-world comparison

The research team drew on the TriNetX US Collaborative Network, spanning 67 healthcare organizations, to identify adults with overweight or obesity and resistant hypertension who started a fourth-line pharmacological therapy between mid-2017 and early 2025. Patients beginning a GLP-1RA (semaglutide or tirzepatide) were compared against patients beginning an MRA (spironolactone or eplerenone). Out of more than 213,000 eligible patients, propensity score matching balanced the two groups on baseline characteristics, leaving 4,153 well-matched patients per arm for analysis. This is an observational design rather than a randomized trial, but the scale and matching approach make it a substantial addition to the evidence base on this specific comparison.

What the data showed

Over a median follow-up of roughly 1.4 years, the GLP-1RA group had a lower rate of major adverse cardiovascular events (MACE) than the MRA group (hazard ratio 0.63), along with lower all-cause mortality (HR 0.34), fewer cardiovascular events generally (HR 0.74), and reduced rates of major adverse kidney events (HR 0.64) and acute kidney injury (HR 0.62). Notably, the blood-pressure reductions themselves were similar between the two groups at 12 weeks — GLP-1RAs did not outperform MRAs on blood pressure lowering, yet were associated with meaningfully better downstream cardiovascular and kidney outcomes.

Reading the results in context

This gap between “similar blood pressure effect” and “different hard outcomes” is the most interesting part of the study, and also the reason to be cautious about over-reading it. As a retrospective, propensity-matched cohort rather than a randomized controlled trial, the study cannot rule out residual confounding — patients selected for a GLP-1RA by their treating physicians may have differed from those selected for an MRA in ways the matching process didn’t fully capture. The authors themselves frame the findings as hypothesis-generating rather than practice-changing, explicitly calling for prospective studies before any treatment-strategy conclusions are drawn. The study also received no external funding, which is worth noting as a data point on independence even as it doesn’t resolve the observational-design limitations.

Why it matters for GLP-1 research

For researchers tracking the GLP-1 receptor agonist literature, this study adds to a growing body of real-world and trial evidence suggesting that GLP-1RAs’ cardiovascular and renal benefits may not be fully explained by their blood-pressure or weight effects alone — a question also being probed through mechanistic work on inflammation, endothelial function, and direct renal signaling. Resistant hypertension in the context of obesity sits at the intersection of several research areas already active in the GLP-1 space, and this comparative framing against a guideline-standard comparator (rather than placebo) is a useful addition to that picture. As always, this kind of population-level association data describes a research question worth pursuing further, not a settled clinical recommendation.

Further reading

• Tian Z, Willerding JM, Schmidt-Ott KM, Melk A, Schmidt BMW. “Comparative effectiveness of GLP-1 receptor agonists versus mineralocorticoid receptor antagonists as fourth-line pharmacological therapy in patients with resistant hypertension and overweight or obesity: a retrospective multicenter cohort study in the USA.” EClinicalMedicine, 2026 Aug 29;99:104176. PubMed: 42701458 · doi.org/10.1016/j.eclinm.2026.104176