Plasma renin activity and aldosterone concentration are not altered by the novel calcium channel antagonist, azelnidipine, in hypertensive patients

How should anti-hypertensive medications be adjusted before screening for primary aldosteronism?

Anti-hypertensive medications may affect plasma renin activity and/or plasma aldosterone concentration, misleading the interpretation of the aldosterone-to-renin ratio when screening for primary aldosteronism. The Task Force of Taiwan PA recommends that, when necessary, using α-adrenergic receptor blocking agents, centrally acting α-adrenergic agonists, and/or non-dihydropyridine calcium channel blockers should be considered to control blood pressure before screening for PA. We recommend temporarily holding β-adrenergic receptor blocking agents, mineralocorticoid receptor antagonists, dihydropyridine calcium channel blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and all diuretics before screening for PA. Further large-scale randomized controlled studies are required to confirm the recommendations.

'I can't understand why others don't screen more': a qualitative study exploring why Australian general practitioners screen for primary aldosteronism

OBJECTIVE

We sought to understand the factors that influence a general practitioner's (GP's) experience of screening for primary aldosteronism (PA) in hypertensive patients.

DESIGN

A qualitative study, framed by phenomenology, using semistructured interviews that were audiorecorded, transcribed verbatim, entered into NVivo V.12.0 for coding and analysed for emerging themes.

SETTING

Melbourne, Australia.

PARTICIPANTS

Eligible GPs had received education on PA as part of a previous study. We recruited a purposive sample of 16 GPs (6 females, 10 males) who varied in practice location, clinical experience and the number of patients screened for PA.

RESULTS

Although GPs had been educated about PA, they found it challenging to explain the condition to patients and were uncertain about how to screen patients who were already taking antihypertensive medications. Most viewed the screening process to be practical, inexpensive and, by and large, acceptable to their patients. However, they found it inconvenient to alter antihypertensive medications before screening to allow for easier interpretation of the aldosterone-renin ratio. They were also less enthused about screening patients whom they thought fitted a clinical picture of essential hypertension. Knowledge of the screening process, cost and convenience of performing the aldosterone-renin ratio, conceptualisation of risk related to PA, and a desire to improve clinical care were influencing factors that modified the GPs' screening experience.

CONCLUSION

Our findings suggest that knowledge gaps, practical limitations of the aldosterone-renin ratio, and errors in diagnostic reasoning were challenges of routine PA screening. Most of these practical barriers could be addressed by relatively simple educational and practice modifications to increase PA screening rates and optimise detection for the most common cause of secondary hypertension in primary care.

The effect of medication on the aldosterone-to-renin ratio. A critical review of the literature

The aldosterone-to-renin ratio (ARR) is a common screening test for primary aldosteronism in hypertensives. However, patients often use medications that could confound the ARR and, thereby, reduce the interpretability of the test. Since it is not always feasible to stop such medication, several drugs that are supposedly neutral with respect to the ARR have been recommended as alternative treatment. The objective of the present review is to explore whether sufficient evidence exists to justify the recommendations. To this end, we performed a systematic PubMed and Cochrane literature search regarding medications that may influence the ARR. Our review revealed that many commonly prescribed antihypertensives seem to have significant effects on renin, aldosterone, and resulting ARR values. However, the magnitude of these effects is poorly quantifiable with the present level of research. We conclude that several medications can affect the ARR. Not taking this into account could lead to misinterpretation of the ARR. Therefore, standardization of the medications used during ARR measurement is advisable for a reliable and accurate interpretation. Further research is needed to ascertain how to best optimize these medications.

Flash glucose monitoring system was applied to cortisol treatment for a patient with congenital adrenal hyperplasia and 17α-hydroxylase deficiency

BACKGROUND

Congenital adrenal hyperplasia (CAH) with 17α-hydroxylase deficiency is a rare disease; patients often require lifetime cortisol treatment. In this case report, we presented a patient with CAH and 17α-hydroxylase deficiency, who was previously misdiagnosed as having primary aldosteronism. Furthermore, the flash glucose monitoring system (FGMS) was used to ascertain a suitable cortisol therapeutic regimen for this patient.

CASE PRESENTATION

A 29-year-old woman presented with sex dysgenesis, hypertension and hypokalaemia. She had been diagnosed with primary aldosteronism at a local hospital. The re-measured aldosterone level in our hospital was below the normal range after antihypertensive medication adjustment, suggesting that the primary aldosteronism was a misdiagnosis. The patient was finally diagnosed as having CAH with 17α-hydroxylase deficiency according to the endocrine profile, adrenocorticotropic hormone stimulation test, and genetic analysis. Then, the patient was recommended cortisol treatment, during which the endocrine profile, blood pressure, plasma potassium level, and blood glucose level were observed to ascertain a suitable dosage. The FGMS was used to monitor blood glucose level, which indicated that the patient's glucose metabolism was maintained normally under the final treatment dosage.

CONCLUSION

The misdiagnosis might have been because of the effects of the antihypertension medications on aldosterone and renin levels. The final dosage of cortisol treatment achieved a normal endocrine profile, while maintaining the homeostasis of blood glucose level, plasma potassium level and blood pressure. FGMS may be an effective method to ascertain a suitable cortisol therapeutic regimen for patients with CAH and 17α-hydroxylase deficiency.

Effect of aldosterone breakthrough on albuminuria during treatment with a direct renin inhibitor and combined effect with a mineralocorticoid receptor antagonist

We have reported observing aldosterone breakthrough in the course of relatively long-term treatment with renin-angiotensin (RA) system inhibitors, where the plasma aldosterone concentration (PAC) increased following an initial decrease. Aldosterone breakthrough has the potential to eliminate the organ-protective effects of RA system inhibitors. We therefore conducted a study in essential hypertensive patients to determine whether aldosterone breakthrough occurred during treatment with the direct renin inhibitor (DRI) aliskiren and to ascertain its clinical significance. The study included 40 essential hypertensive patients (18 men and 22 women) who had been treated for 12 months with aliskiren. Aliskiren significantly decreased blood pressure and plasma renin activity (PRA). The PAC was also decreased significantly at 3 and 6 months; however, the significant difference disappeared after 12 months. Aldosterone breakthrough was observed in 22 of the subjects (55%). Urinary albumin excretion differed depending on whether breakthrough occurred. For the subjects in whom aldosterone breakthrough was observed, eplerenone was added. A significant decrease in urinary albumin excretion was observed after 1 month, independent of changes in blood pressure. In conclusion, this study demonstrated that aldosterone breakthrough occurs in some patients undergoing DRI therapy. Aldosterone breakthrough affects the drug's ability to improve urinary albumin excretion, and combining a mineralocorticoid receptor antagonist with the DRI may be useful for decreasing urinary albumin excretion. When the objective is organ protection in hypertensive patients, a two-pronged approach using combination therapy to inhibit both the RA system and aldosterone may be highly effective.

Effects of Azelnidipine plus OlmesaRTAn versus amlodipine plus olmesartan on central blood pressure and left ventricular mass index: the AORTA study

PURPOSE

The aim of this study was to compare the effects of olmesartan combined with either azelnidipine or amlodipine on central blood pressure (CBP) and left ventricular mass index (LVMI) in hypertensive patients.

PATIENT AND METHODS

Patients with brachial systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg received olmesartan monotherapy (20 mg daily) for 12 weeks. The patients were then randomly assigned to fixed-dose add-on therapy with azelnidipine (16 mg daily) or amlodipine (5 mg daily) (25 patients/group) for a further 24 weeks. CBP and LVMI were measured at baseline and at the end of the study.

RESULTS

Baseline characteristics were similar in both groups. The decrease in brachial BP was similar in both groups. CBP and LVMI decreased significantly in both groups (both, P < 0.001). However, the decreases in CBP and LVMI were significantly greater with olmesartan/azelnidipine than with olmesartan/amlodipine (CBP, P < 0.001; LVMI, P = 0.002).

CONCLUSIONS

These findings indicate that olmesartan/azelnidipine had greater effects on CBP and LVMI than did olmesartan/amlodipine, even though the reduction in brachial BP was similar in both groups. These differential effects on CBP and LVMI may have important implications for cardiovascular risk reduction.