Endocrine Abstracts

Background: The higher prevalence of urinary albumin was reported in patients with primary aldosteronism (PA) than those with essential hypertension (EH). It remains to be unclear, although ‘glomerular hyperfiltration (HF)’ was hypothesized as one of the mechanisms of urinary albumin.

Objectives: To clarify the risk factor of urinary albumin and the relationship with HF in PA.

Methods: 123 patients with PA were treated according to the result of adrenal vein sampling. Adrenalectomy was performed on patients diagnosed with unilateral disease (APA: n=68), while those who were diagnosed with bilateral disease were given medical treatment including with mineralcorticoid receptor antagonists (MRA; IHA: n=55).

Blood pressure, estimated glomerular filtration rate (eGFR:ml/min per 1.73 m²) and urinary albumin excretion (UAE:mg/g Creatinine) were followed at baseline and during 24 months after treatment of PA in all patients. Multivariate regression analysis with stepwise procedure was performed to identify the potential risk factor of baseline UAE and the relation factor with the decline of GFR (ΔGFR) between at baseline and at 1 month after treatment. eGFR was estimated by the equation for Japanese established by Japan society of nephrology. UAE was adjusted by logarithm.

Results: Blood pressure, UAE, and GFR significantly decreased at 1 month after treatment and they remained a plateau during the follow-up. Positive relationship was observed between UAE and ΔGFR (P=0.0003, R²=0.165). Baseline plasma aldosterone concentration and systolic blood pressure were the risk factors of UAE (P=0.010 and P=0.013, respectively, R²=0.164). Baseline UAE and serum potassium were the predictors of ΔGFR (P<0.01, R²=0.275).

Conclusion: In primary aldosteronism, plasma aldosterone concentration is an independent risk factor for albuminuria, and the higher baseline urinary albumin excretion predicts the less glomerular filtration rate after treatment.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.