Preeclampsia: A Diagnosis-Nondiagnosis That Is Too Easily Made: The Case of Primary Hyperaldosteronism

Variable effect of the post-partum menstrual cycle on aldosterone and renin in women with recent preeclampsia

The purpose of the present study is to identify the impact of the postpartum menstrual cycle on aldosterone, renin, and their ratio of women with and without a preeclamptic pregnancy in the past. To this end, we analysed the data from 59 women with a history of preeclampsia and 39 healthy parous controls. Five to seven months post-partum, we measured aldosterone, renin, and the aldosterone-to-renin ratio during both the follicular and the luteal phase of the menstrual cycle. All measurements were taken in the supine position in the morning. Patients had maintained a standardized sodium diet in the week prior to the measurements. Our results show that in both post-partum women with recent preeclampsia and controls, average levels of renin and aldosterone are significantly elevated in the luteal phase as compared to the follicular phase. The aldosterone-to-renin ratio does not differ between the two phases in either group. Compared to controls, women with recent preeclampsia have significantly lower levels of renin, aldosterone, and aldosterone-to-renin ratio in the follicular phase. This remained consistent in the luteal phase, except for renin. A close correlation existed between the luteal and follicular aldosterone-to-renin ratio in the control group but not in the preeclampsia group. We conclude that both renin and aldosterone are significantly affected by the menstrual cycle whereas the resulting aldosterone-to-renin ratio is not. Post-partum women with recent preeclampsia tend to have lower values for aldosterone and the aldosterone-to-renin ratio than controls.

Primary aldosteronism in pregnancy

Primary aldosteronism (PA) is the most common form of secondary hypertension. Although hypertensive disorders seem to affect around 5-10% of pregnancies worldwide, literature counts less than 80 cases of PA diagnosed during the peri-partum period. In this review we discuss about current knowledge on pathophysiology, natural history, diagnosis and treatment of PA in pregnancy. Because of the physiologic changes in the renin-angiotensin-aldosterone system (RAAS) and the contraindication to both confirmatory test and subtype differentiation, diagnosis of PA during pregnancy is challenging and relies mostly on detection of low/suppressed renin and high aldosterone levels. The course of pregnancy in patients with PA is highly variable, ranging from progesterone-induced amelioration of blood pressure (BP) control to severe and resistant hypertension with potential maternal and fetal complications. Mineralcorticoid receptor antagonists (MRA) are the recommended and most effective drugs for treatment of PA. As the anti-androgenic effect of spironolactone can potentially interfere with sexual development, their prescription is not recommended during pregnancy. On the other side, eplerenone, has proven to be safe and effective in 6 pregnant women and may be added to conventional first line drug regimen in presence of resistant hypertension or persistent hypokalemia. Ideally, patients with unilateral forms of PA should undergo adrenalectomy prior to conception, however, when PA is diagnosed during pregnancy and medical therapy fails to adequately control hypertension or its complications, adrenalectomy can be considered during the second trimester in case of unilateral adrenal mass at MRI-scan.

Management and Outcomes of Primary Aldosteronism in Pregnancy: A Systematic Review

Primary aldosteronism (PA) in pregnancy (PAP) can be a serious condition and is challenging to diagnose. This study was conceived to help in the diagnosis of PAP and provide suggestions on management of PAP based on evidence retrieved using a Population, Intervention, Comparison, and Outcome search strategy. Based on the changes of aldosterone and renin occurring in normal pregnancies, we developed a nomogram that will allow to identify PAP cases. Moreover, we found that published PAP cases fell into 4 main groups differing for management and outcomes: (1) unilateral medically treated, (2) unilateral surgically treated, (3) bilateral medically treated and (4) familial forms. Results showed that complications involved 62.2% of pregnant women with nonfamilial PA and 18.5% of those with familial hyperaldosteronism type I. Adrenalectomy during pregnancy in women with PAP did not improve maternal and fetal outcomes, over medical treatment alone. Moreover, cure of maternal hypertension and mother and baby outcome were better when unilateral PA was discovered and surgically treated before or after pregnancy. Therefore, fertile women with arterial hypertension should be screened for PA before pregnancy and, if necessary, subtyped to identify unilateral forms of PA. This will allow to furnish adequate counseling, a chance for surgical cure and, therefore, for a pregnancy not complicated by aldosterone excess.

Assessment and Management of Primary Aldosteronism in Pregnancy: A Case-Control Study

CONTEXT

Primary aldosteronism (PA) is a common secondary cause of hypertension. Literature regarding PA in pregnancy has demonstrated poor outcomes.

OBJECTIVE

Compare the management and outcomes of PA in pregnancy to both high and low-risk matched controls.

METHODS

This was a case-control trial conducted in a network of metropolitan hospitals in Sydney, Australia. PA women (positive salt suppression test) with singleton pregnancies delivered after 20 weeks' gestation were matched to women with high- and low-risk pregnancies. Management outcomes included pre-eclampsia prophylaxis and antihypertensive medications required prenatally, antenatally, and postnatally. Maternal outcomes included incidence of pre-eclampsia, gestational diabetes, hypokalemia, mode of delivery, and length of stay postpartum. Neonatal outcomes included gestation, birthweight, intensive care unit admission, and length of stay.

RESULTS

Fifty-nine women with 60 pregnancies were included (20 PA, 20 high risk, and 20 low risk). The number of antihypertensive medications women with PA took prepregnancy was similar to the high-risk group. A similar proportion of women in the PA and high-risk groups were prescribed pre-eclampsia prophylaxis and developed pre-eclampsia. Even after adjustment for several factors, PA was not independently associated with pre-eclampsia development. Women with PA had higher antihypertensive requirements and a longer stay in hospital postpartum than the high-risk group (both P = .02). There was no difference in neonatal adverse outcomes. Four women took epleronone during pregnancy without any adverse effects noted.

CONCLUSION

Women with PA required more antihypertensives and had a longer postpartum length of stay than matched high-risk women, but similar rates of pre-eclampsia. There was no difference in the rate of neonatal intensive care admissions or adverse outcomes for neonates.