Hyperparathyroidism in patients with primary aldosteronism: cross-sectional and interventional data from the GECOH study.
BACKGROUND
Experimental studies suggest that aldosterone induces hypercalciuria and might contribute to hyperparathyroidism.


OBJECTIVE
We aimed to test for differences in PTH levels and parameters of calcium and vitamin D metabolism in patients with primary aldosteronism (PA) compared with patients with essential hypertension (EH) and to evaluate the impact of PA treatment on these laboratory values.


METHODS
The Graz Endocrine Causes of Hypertension study includes hypertensive patients referred for screening for endocrine hypertension at a tertiary care center in Graz, Austria.


METHODS
Differences in PTH levels between patients with PA and EH.


RESULTS
Among 192 patients, we identified 10 patients with PA and 182 with EH. PTH levels (mean ± sd in picograms per milliliter) were significantly higher in PA patients compared with EH (67.8 ± 26.9 vs. 46.5 ± 20.9; P = 0.002). After treatment of PA with either adrenal surgery (n = 5) or mineralocorticoid receptor antagonists (n = 5), PTH concentrations decreased to 43.9 ± 14.9 (P = 0.023). Serum 25-hydroxyvitamin D concentrations were similar in both groups. Compared with EH, serum calcium concentrations were significantly lower (2.35 ± 0.10 vs. 2.26 ± 0.10 mmol/liter; P = 0.013), and there was a nonsignificant trend toward an increased spot urine calcium to creatinine ratio in PA [median (interquartile range) 0.19 (0.11-0.31) vs. 0.33 (0.12-0.53); P = 0.094].


CONCLUSIONS
Our results suggest that PA contributes to secondary hyperparathyroidism. Further studies are warranted to evaluate whether PTH has implications for PA diagnostics and whether mineralocorticoid receptor antagonists have a general impact on PTH and calcium metabolism.
Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Auenbruggerplatz 15, 8036 Graz, Austria. stefan.pilz@chello.at
Stefan
S
Pilz
Katharina
K
Kienreich
Christiane
C
Drechsler
Eberhard
E
Ritz
Astrid
A
Fahrleitner-Pammer
Martin
M
Gaksch
Andreas
A
Meinitzer
Winfried
W
März
Thomas R
TR
Pieber
Andreas
A
Tomaschitz
D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002986:Clinical Trials as Topic / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006929:Hyperaldosteronism / Q000097:blood / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D006961:Hyperparathyroidism / Q000097:blood / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D006973:Hypertension / Q000097:blood / Q000150:complications / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D012084:Renin-Angiotensin System / Q000502:physiology
D010281:Parathyroid Hormone; D000450:Aldosterone