Enhanced Soluble Serum CD40L and Serum P-Selectin Levels in Primary Aldosteronism

Primary aldosteronism (PA) is one of the most frequent forms of secondary hypertension, associated with atherosclerosis and higher risk of cardiovascular events. Platelets play a key role in the atherosclerotic process. The aim of the study was to evaluate the platelet activation by measuring serum levels of soluble CD40L (sCD40L) and P-selectin (sP-selectin) in consecutive PA patients [subgroup: aldosterone-secreting adrenal adenoma (APA) and bilateral adrenal hyperplasia (IHA)], matched with essential hyper-tensive (EH) patients. The subgroup of APA patients was revaluated 6-months after unilateral adrenalectomy. In all PA group, we measured higher serum levels of both sP-selectin (14.29 +/- 9.33 pg/ml) and sCD40L (9.53 +/- 4.2 ng/ml) compared to EH patients (9.39 +/- 5.3 pg/ml and 3.54 +/- 0.94 ng/ml, respectively; p < 0.001). After removal of APA, PA patients showed significant reduction of blood pressure (BP) values, plasma aldosterone (PAC) levels and ARR-ratio, associated with a significant reduction of sP-selectin (16.74 +/- 8.9 pg/ml vs. 8.1 +/- 3.8 pg/ml; p < 0.01) and sCD40L (8.6 +/- 1 ng/ml vs. 5.24 +/- 0.94 ng/ml; p < 0.001). In PA patients, we found a significant correlation between sPselectin and sCD40L with PAC (r = 0.52, p < 0.01; r = 0.50, p < 0.01, respectively); this correlation was stronger in APA patients (r = 0.54; p < 0.01 r = 0.63; p < 0.01, respectively). Our results showed that PA is related to platelet activation, expressed as higher plasma values of sCD40L and sP-selectin values. Surgical treatment and consequent normalization of aldosterone secretion was associated with significant reduction of sCD40L and sP-selectin values in APA patients.