Primary aldosteronism (PA) can be treated medically to achieve blood pressure control and cardiovascular risk reduction. However, there is no standardised approach to assess treatment outcomes. We aimed to establish criteria for assessing the outcomes of targeted medical treatment of PA, evaluate outcomes in an international cohort and identify factors associated with a complete treatment response.
An international panel of 31 PA experts used the Delphi method to reach consensus. Clinical data were collected from patients with PA who started medical treatment between 2016 and 2021 at 28 participating centres.
Consensus was reached for defining complete, partial, or absent biochemical or clinical response. Of 1258 patients (52 ± 11.5 years, 48% female), 1047 had paired clinical and biochemical outcome data at 6-12 months post-treatment and 106 (10.1%) had both complete biochemical and clinical responses. Of the 1057 patients with biochemical outcome data, 52.9% had a complete biochemical response, while 20% had an absent response. The daily dose of spironolactone, the most commonly used medical therapy, was significantly higher in the complete biochemical responders than absent responders (40mg vs 25mg, p=0.011). Of the 1248 patients with clinical outcome data, 18% had a complete clinical response and 16% had an absent response. Patients with a complete clinical response were more likely to be women (OR 2.037, p<0.001), require fewer antihypertensive drugs at baseline (OR 0.636, p<0.001) and less likely to have microalbuminuria or left ventricular hypertrophy at baseline (OR 0.569, p=0.007).
The PAMO criteria represent an internationally recognised outcome standard which can guide clinical practice and research. By applying the criteria to an international patient cohort, we show that the rates of complete clinical and biochemical response are sub-optimal. Efforts to optimise treatment intensity and minimize factors associated with an absent treatment response will be needed to improve patient outcomes.