A multicentric prospective study of the aldosterone/plasma renin activity ratio in a population of Argentina for screening of primary aldosteronism

PARDES E, GOMEZ R, BELLI S, CONTRERAS LN, CHERVIN R, CORNALÓ D, DAMILANO S, FENILI C, LEAL M, LUPI S, NOFAL MT, ROSSI MA, RUIBAL MT

Rio de Janeiro, Brasil

Congreso; International Congress of Endocrinology; 2008

Primary aldosteronism (PA) is no longer a rare cause of arterial hypertension since the aldosterone/plasma renin activity ratio (RR) is considered as the screening method independently of hypokalemia. The plasma renin activity (PRA) determination is a laborious method with low reproducibility. It has a direct influence on the ARR value. thus, each working group must assess its own cut-off level. the aim of our study was to determine the ARR cut-off value for the screening of PA in our hypertensive patients. Material and methods: we studied 353 subjects out of 440 otiginally recruited during 2003-2006. The control group (CG, n: 104) was normotensive first degree relatives. the hypertensive group (HG) consisted of 249 patients. Blood was withrawn between 8 and 10 am in the upright position for aldosterone and PRA with a normal sodium diet. plasma renin concentration(PRC) was also assessed in 194 subjects. Results: as the ARR variable in CG showed a non-normal distribution, the cut-off value was established in 36 ( 95 percentile) Conclusions. this is the first multicentric study performed in Argentina to determine ARR cut-off level. the value of 36 agrees with the literature reference level. Thus, ARR >36 leads to suspect PA in our essential hypertensive population.