Prevalence, Subtype Classification, and Outcomes of Treatment of Primary Aldosteronism: A Prospective Study in China

Primary Aldosteronism Prevalence - An Unfolding Story

Primary aldosteronism (PA) is characterized by dysregulated, renin-independent aldosterone excess. Long perceived as rare, PA has emerged as one of the most common causes of secondary hypertension. Failure to recognize and treat PA results in cardiovascular and renal complications, through processes mediated by both direct target tissue insults and indirectly, by hypertension. PA spans a continuum of dysregulated aldosterone secretion, which is typically recognized in late stages after treatment-resistant hypertension and cardiovascular and/or renal complications develop. Determining the precise disease burden remains challenging due to heterogeneity in testing, arbitrary thresholds, and populations studied. This review summarizes the reports on PA prevalence among the general population and in specific high-risk subgroups, highlighting the impact of rigid versus permissive criteria on PA prevalence perception.

Primary Aldosteronism: State-of-the-Art Review

We are witnessing a revolution in our understanding of primary aldosteronism (PA). In the past 2 decades, we have learned that PA is a highly prevalent syndrome that is largely attributable to pathogenic somatic mutations, that contributes to cardiovascular, metabolic, and kidney disease, and that when recognized, can be adequately treated with widely available mineralocorticoid receptor antagonists and/or surgical adrenalectomy. Unfortunately, PA is rarely diagnosed, or adequately treated, mainly because of a lack of awareness and education. Most clinicians still possess an outdated understanding of PA; from primary care physicians to hypertension specialists, there is an urgent need to redefine and reintroduce PA to clinicians with a modern and practical approach. In this state-of-the-art review, we provide readers with the most updated knowledge on the pathogenesis, prevalence, diagnosis, and treatment of PA. In particular, we underscore the public health importance of promptly recognizing and treating PA and provide pragmatic solutions to modify clinical practices to achieve this.

Assessment of biochemical outcomes in patients with primary aldosteronism after adrenalectomy based on CT scan diagnosis of unilateral adenoma without adrenal vein sampling

PURPOSE

The purpose of this study was to assess the surgical outcomes of patients with primary aldosteronism when surgery was based only on CT finding of unilateral adenoma without adrenal vein sampling (AVS).

METHODS

This is a retrospective review of the records of patients who had undergone retroperitoneal laparoscopic adrenalectomy for primary aldosteronism based on CT scan finding of unilateral adenoma and had a follow-up of at least 6-12 months from January 2012 to December 2020 in a single center; decision for adrenalectomy was based on CT scan, and AVS was not used. The clinical and biochemical outcomes were accessed using the standardized primary aldosteronism surgical outcome (PASO) criteria. Patient's demographics and preoperative factors were analyzed to assess for independent predictor of surgical success.

RESULTS

According to the PASO criteria, 172 patients finally enrolled in the training dataset, and 20 patients enrolled in the validation dataset. In the training dataset, complete clinical success was achieved in 71 patients (41.3%), partial success in 87 (50.6%), and absent success in 14 (8.1%). Biochemical outcomes showed that 151 patients (87.8%) were completely cured, 14 patients (8.1%) got a partial biochemical success, and an absent biochemical success was found in seven patients (4.1%). Multivariate logistic regression analysis showed that age, body mass index (BMI), tumor size, mean arterial pressure (MAP), and serum potassium were the most independent factors for incomplete biochemical success. Based on the results of statistical analysis, our study constructed a nomogram prognostic evaluation model for patients after unilateral primary aldosterone surgery.

CONCLUSIONS

Laparoscopic adrenalectomy for patients with primary aldosteronism base on CT scan finding of a unilateral adenoma without AVS had a high rate of complete biochemical cure at 12 months. Risk factors for incomplete biochemical success include age, BMI, tumor size, MAP, and serum potassium. Our study constructed a nomogram prognostic evaluation model for patients after unilateral primary aldosterone surgery. The nomogram accurately and reliably predicted the incomplete biochemical success.

Use the right kidney contour as a landmark in adrenal vein sampling

Adrenal Vein Sampling (AVS) is the gold standard for categorizing primary aldosteronism (PA). However, catheterization of the right adrenal vein (RAV) is challenging due the small size and variable location. This study aims to explore the relationship between the RAV orifice and the right kidney contour (RKC) on fluoroscopy, thus evaluating the potential of use the RKC as an anatomic marker for localizing RAV. Imaging data of 107 PA patients with successful bilateral AVS were retrospectively analyzed. Based on the body mass index (BMI), all patients were divided into the Normal Group (BMI < 24 kg/m²), Overweight Group (24 kg/m² ≤ BMI < 28 kg/m²) and Obese Group (BMI ≥ 28 kg/m²). At the anterior view, the height level of RAV orifice was determined relative to vertebral bodies and disks. The distance from the RAV orifice to the upper edge of RKC was measured manually. The RAV orifice height level was mainly distributed from vertebral T11 to T12 (90.6%), and tended to be higher in patients with a larger BMI. The mean distance from the RAV orifice to the upper edge of RKC was 13.9±7.8mm, and had no difference among Normal group (n = 53, 14.1±8.2mm), Overweight group (n = 39, 13.7±8.0mm), and Obese group (n = 15, 13.9±5.5mm) (p = 0.981). Based on these findings, the RKC might be used as a landmark for localizing RAV on fluoroscopy, which is conductive to narrow down the exploration range and increase the success rate of RAV catheterization.

[Risk factors of persistent hypertension in primary aldosteronism patients after surgery]

OBJECTIVE

To analyze the risk factors of persistent hypertension in patients who underwent adrenalectomy for primary aldosteronism and to evaluate the predictive value of the aldosteronoma resolution score (ARS) scoring system for surgical outcomes of adrenalectomy for primary aldosteronism.

METHODS

We reviewed the clinical characteristics of patients who underwent adrenalectomy for primary aldosteronism from 2018 to 2021 at Peking University People' s Hospital to recognize risk factors of uncured hypertension after surgery. Based on the patient' s clinical outcomes, the patients were divided into complete success group and partial/absent success group. Risk factors for persistent hypertension were analyzed. The value of the ARS scoring system was assessed by the area under the curve (AUC).

RESULTS

In this study, 112 patients were included. Most of the patients benefited from the surgery for 94.6% were a complete or partial clinical success after follow-up for at least 6 months. According to postoperative hypertension status, the patients were divided into complete success group (51 cases) and partial/absent success group (61 cases). There were statistical differences between the two groups in age, body mass index (BMI), waist circumference, duration of hypertension, number of preoperative antihypertension medications, preoperative systolic blood pressure, history of diabetes, history of cardiovascular and cerebrovascular diseases, serum creatinine, estimated glomerular filtration rate(eGFR), high-density lipoprotein cholesterol and triglyceride. Logistic regression analysis showed that age (OR=1.111, 95%CI: 1.029-1.199), waist circumference (OR=1.073, 95%CI: 1.013-1.137), pre-operative systolic blood pressure (OR=1.033, 95%CI: 1.008-1.060) and history of cardiovascular and cerebrovascular diseases (OR=16.061, 95%CI: 1.312-196.612) were the risk factors for uncured hypertension in primary aldosteronism patients after surgery, but female gender not. The median ARS in the complete success group was 4 and in the partial/absent success group, it was 2. Among the patients with ARS of 4-5, the cure rate of hypertension was 76.5%. The area under the curve of ARS was 0.743.

CONCLUSION

The history of cardiovascular and cerebrovascular diseases is a significant risk factor for persistent hypertension after surgery in primary aldosteronism patients. ARS scoring system has a certain value in predicting the postoperative hypertension status of primary aldosteronism patients. However, further research is still needed on a prediction model for surgical outcomes of primary aldosteronism which is more suitable for the Chinese population is still needed.

Morphologically Normal-Appearing Adrenal Glands as a Prevalent Source of Aldosterone Production in Primary Aldosteronism

BACKGROUND

Normal-appearing adrenal glands on cross-sectional imaging may still be the source of aldosterone production in primary aldosteronism (PA).

METHODS

We evaluated the prevalence of aldosterone production among morphologically normal-appearing adrenal glands and the impact of this phenomenon on interpretations of localization studies and treatment decisions. We performed a retrospective cohort study of PA patients with at least 1 normal adrenal gland and reanalyzed contemporary studies to assess interpretations of imaging and adrenal venous sampling (AVS) at the individual patient and adrenal levels.

RESULTS

Among 243 patients, 43 (18%) had bilateral normal-appearing adrenals and 200 (82%) had a unilateral normal-appearing adrenal, for a total of 286 normal-appearing adrenal glands. 38% of these normal-appearing adrenal glands were a source of aldosteronism on AVS, resulting in discordance between imaging and AVS findings in 31% of patients. Most patients with lateralizing PA underwent curative unilateral treatment (80%); however, curative treatment was pursued in 92% of patients who had concordant imaging-AVS results but in only 38% who had discordant results (P < 0.05). In young patients, imaging-AVS discordance was detected in 32% of those under 45 years and 21% of those under 35 years. Among 20 contemporary studies (including 4,904 patients and 6,934 normal-appearing adrenal glands), up to 64% of normal-appearing adrenals were a source of aldosteronism resulting in 31% of patients having discordant results.

CONCLUSIONS

Morphologically normal-appearing adrenal glands are commonly the source of aldosterone production in PA, even among young patients. The lack of awareness of this issue may result in inappropriate treatment recommendations.

[Expert opinion. Spironolactone: a new twist on an old story]

The article presents recent data on possibilities of a broader use of mineralocorticoid receptor antagonists for existing indications and of expanding indications for the use of this pharmaceutical group in the context of the novel coronavirus infection COVID-19. The authors discussed prospects for expanded detection of aldosteronism using a new diagnostic approach, including an additional evaluation of blood pressure response to spironolactone.