Long-term renal outcomes in patients with primary aldosteronism.
BACKGROUND
Experimental animal studies indicate that exposure to increased aldosterone levels might result in renal damage, but the clinical evidence supporting this role of aldosterone is preliminary.


OBJECTIVE
To determine the long-term outcome of renal function in patients with primary aldosteronism after surgical or medical treatment.


METHODS
Prospective study conducted at an Italian university medical center among a consecutive sample of 50 patients who were diagnosed as having primary aldosteronism between January 1994 and December 2001 and who were followed up for a mean of 6.4 years after treatment with adrenalectomy or spironolactone. Patients with primary aldosteronism were compared with 100 patients with essential hypertension, matched for severity and duration of hypertension. All patients were treated with antihypertensive drugs to reach a target blood pressure of less than 140/90 mm Hg.


METHODS
Primary outcome measures were rates of change of glomerular filtration rate and albuminuria during follow-up. Detection of new-onset microalbuminuria and restoration of normal albumin excretion during follow-up were considered as secondary outcomes.


RESULTS
At baseline, glomerular filtration rate and albuminuria were higher in patients with primary aldosteronism than those with essential hypertension. The mean blood pressure during the study was 136/81 mm Hg in the primary aldosteronism group and 137/81 mm Hg in the essential hypertension group. Glomerular filtration rate and albuminuria declined during the initial 6-month period in both groups, with a change that was significantly greater (P<.001 for both variables) in patients with primary aldosteronism. Subsequent rate of decline of glomerular filtration was comparable in the 2 groups, whereas albuminuria did not progress in the remainder of the follow-up. Restoration of normal albumin excretion from microalbuminuria was significantly more frequent in primary aldosteronism than in essential hypertension (P = .02).


CONCLUSIONS
In the majority of patients in this study, primary aldosteronism was characterized by partially reversible renal dysfunction in which elevated albuminuria is a marker of a dynamic rather than structural renal defect.
Sechi
Leonardo A
LA
Hypertension Unit, Division of Internal Medicine, Department of Experimental and Clinical Pathology and Medicine, University of Udine, Udine, Italy. sechi@uniud.it
Novello
Marileda
M
Lapenna
Roberta
R
Baroselli
Sara
S
Nadalini
Elisa
E
Colussi
Gian Luca
GL
Catena
Cristiana
C
D000315:Adrenalectomy; D000328:Adult; D000419:Albuminuria / Q000209:etiology; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D006929:Hyperaldosteronism / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D006973:Hypertension / Q000209:etiology; D007674:Kidney Diseases / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D000451:Mineralocorticoid Receptor Antagonists / Q000627:therapeutic use; D011446:Prospective Studies; D013148:Spironolactone / Q000627:therapeutic use
D000451:Mineralocorticoid Receptor Antagonists; D013148:Spironolactone