Presentation Authors: Hayato Yamamoto*, Shingo Hatakeyama, Teppei Matsumoto, Yuichiro Suzuki, Tohru Yoneyama, Atsushi Imai, Takahiro Yoneyama, Yasuhiro Hashimoto, Shinobu Takayasu, Shigeyuki Nakaji, Chikara Ohyama, Hirosaki, Japan
Introduction: Patient selection for confirmatory tests of primary aldosteronism (PA) is one of the challenges in clinical practice because of fluctuations in serum aldosterone and renin concentrations. The aim of the present study was to validate the PA discrimination score that we created for the selection criteria of confirmatory tests.
Methods: An aldosteroneâ€“renin ratio cutoff â‰¥200, with plasma aldosterone concentration (PAC) â‰¥120 pg/mL was used for PA screening. We developed a discrimination formula (-1*(PAC*-0.0067 + plasma renin activity*0.0546 + presence of hypertension (HTN)*-1.0433 + serum potassium levels (K)*1.6904-5.3494)) for the selection criteria of confirmatory tests. For this discrimination formula, we included 123 patients with PA who underwent unilateral adrenalectomy in our hospital between 2000 and 2017 as positive patients with PA. As negative controls, we selected 2143 PA screening-negative subjects in comprehensive medical examinations of PA for 2276 individuals of the community-dwelling population who presented to the Iwaki Health Promotion project between May 2014 and May 2015. For this validation study, we analyzed two groups: PA-positive and -negative cases. PA-positive patients comprised 10 patients with PA who underwent unilateral adrenalectomy in our hospital in 2018. PA-negative patients comprised 19 patients who underwent confirmatory tests for PA in our hospital, but did not fulfill the diagnosis of PA. Predictive accuracy of the PA discrimination score was evaluated based on ROC analysis and area under the curve (AUC). In addition, we analyzed the discrimination scores from medical examinations of PA in 1148 individuals of the community-dwelling population in 2016.
Results: The discrimination formula showed a significant association with PA diagnosis (AUC: 0.97). Of the 1148 subjects, 314 (27%) were HTN patients. Thirty-one (9.9%) were positive for PA screening, representing an overall prevalence of 2.7%. We could detect 7 subjects with the cutoff value of 1.5 that were strongly suspicious for PA.
Conclusions: The PA discrimination score may improve the diagnostic accuracy of PA in screening settings. Further validation studies are warranted.