eplerenone and Hyperparathyroidism

The following review presents recent diagnostic and therapeutic developments in the field of endocrinology. With the development of strontium ranelate and teriparatide (human recombinant parathyroid hormone) two new drugs are now available for the treatment of postmenopausal osteoporosis. In addition, the therapeutic use of the calcimimetic agent cinacalcet in the treatment of primary and secondary hyperparathyroidism is discussed. The recent introduction of a novel, long-acting testosterone formulation (testosterone undecanoate) which only requires one intramuscular injection every 3 months, together with the already available hydroalcoholic testosterone gels, appear to be promising alternatives to the previous standard substitution therapy for male hypogonadism. Recently, the mineralocorticoid hormone aldosterone has gained much interest due to its central pathophysiological role in secondary hypertension and its potential deleterious role as a cardiovascular risk factor in nonepithelial target tissues. In this context, the therapeutic potential of a new selective mineralocorticoid receptor antagonist, eplerenone, will be ventilated. In addition, (18)F-DOPA positron emission tomography ((18)F-DOPA-PET), a new functional imaging modality for the diagnostic localization of chromaffin tumors, will be presented and the role of the somatostatin receptor radionuclide therapy with (90)Y-[DOTA](0)-Tyr(3)-octreotide ((90)Y-DOTATOC) for the treatment of advanced neuroendocrine tumors discussed. Furthermore, the ongoing controversy about the diagnosis and treatment of subclinical hypothyroidism will be summarized.

Topics: Adrenal Gland Neoplasms; Adult; Bone Density Conservation Agents; Chronic Kidney Disease-Mineral and Bone Disorder; Cinacalcet; Clinical Trials as Topic; Endocrinology; Eplerenone; Female; Humans; Hyperaldosteronism; Hyperparathyroidism; Hyperparathyroidism, Primary; Hyperparathyroidism, Secondary; Hypogonadism; Hypothyroidism; Male; Naphthalenes; Neuroendocrine Tumors; Organometallic Compounds; Osteoporosis, Postmenopausal; Pheochromocytoma; Positron-Emission Tomography; Pregnancy; Radiography, Abdominal; Spironolactone; Teriparatide; Testosterone; Testosterone Congeners; Thiophenes; Time Factors; Tomography, X-Ray Computed

Current guidelines recommend to withdraw mineralocorticoid receptor (MR) blocker treatment for at least 4 weeks when measuring the aldosterone to renin ratio (ARR) as a screening test for primary aldosteronism (PA). We aimed to evaluate the effect of MR blocker treatment on ARR and its components, plasma aldosterone concentration (PAC), and direct renin concentration (DRC). First, we performed a post-hoc analysis of the effect of eplerenone on parathyroid hormone levels in primary hyperparathyroidism (EPATH) study, a randomized controlled trial (RCT) in 110 patients with primary hyperparathyroidism (pHPT). Patients were 1:1 randomly assigned to receive either 25 mg eplerenone once daily (up-titration after 4 weeks to 50 mg/day) or placebo for 8 weeks. Second, we measured the ARR in 4 PA patients from the Graz Endocrine Causes of Hypertension Study (GECOH) before and after MR blocker treatment. Ninety-seven participants completed the EPATH trial, and the mean treatment effect (95% confidence interval) for log(e)ARR was 0.08 (-0.32 to 0.48) ng/dl/μU/ml (p=0.694). The treatment effect was 0.71 (0.47 to 0.96; p<0.001) ng/dl for log(e)PAC and 0.64 (0.19 to 1.10; p=0.006) μU/ml for log(e)DRC, respectively. In the 4 PA patients, the ARR decreased from 11.24±3.58 at baseline to 2.70±1.03 (p=0.013) ng/dl/μU/ml after MR blocker treatment. In this study with limited sample size, MR blocker treatment did not significantly alter the ARR in pHPT patients but significantly reduced the ARR in PA patients. Diagnostic utility of ARR and its components for PA diagnostics under MR blocker treatment warrants further study.

Topics: Aged; Aldosterone; Double-Blind Method; Eplerenone; Female; Humans; Hyperaldosteronism; Hyperparathyroidism; Male; Middle Aged; Mineralocorticoid Receptor Antagonists; Renin; Spironolactone; Time Factors