Page 1 of 23 Accepted Preprint first posted on 8 January 2009 as Manuscript EJE-08-0902 SMALL TUMOR SIZE AS FAVOURABLE PROGNOSTIC FACTOR AFTER ADRENALECTOMY IN CONN S ADENOMA 1 Gilberta Giacchetti, 1 Vanessa Ronconi, 1 Silvia Rilli, 2 Mario Guerrieri, 1 Federica Turchi, 1 Marco Boscaro 1 Division of Endocrinology, 2 Department of General Surgery-Clinica di Chirurgia Generale e Metodologia Chirurgica Azienda Ospedaliero-Universitaria, Ospedali Riuniti Umberto I-GM Lancisi-G Salesi, Università Politecnica delle Marche, Via Conca 71, 60121 Torrette, Ancona, Italy Short running title: tumor size as prognostic factor in Conn s adenoma Word count, including abstract and references: 5155 Corresponding author s address: Dr. Gilberta Giacchetti Clinica di Endocrinologia Universita Politecnica delle Marche Via Conca71, 60020 Torrette, Ancona, Italy Phone: +39-071-5964417 Fax: +39-071-887300 e-mail: g.giacchetti@ospedaliriuniti.marche.it Copyright 2009 European Society of Endocrinology.
Page 2 of 23 Abstract Objective: Primary aldosteronism (PA) due to aldosterone producing adenoma (APA) is the most common curable form of secondary hypertension. Design: In order to evaluate blood pressure outcome after adrenalectomy for APA and to identify new favourable prognostic factors, data from 42 consecutive APA patients who underwent adrenalectomy were collected from 2005 to 2007. Methods: Renin angiotensin aldosterone system (upright and postsaline infusion test), serum and urinary electrolytes, office and ambulatory blood pressure monitoring were evaluated at baseline and after a follow up of 2.7±2.2 years. Drug history and adenoma size at morphological evaluation were also collected. Results: Multiple regression analysis showed that before surgery patients with a small adenoma (diameter <20 mm) displayed higher postsaline aldosterone values (p=0.0001), and lower serum potassium levels (p=0.020), than patients with adenoma >20 mm. Before surgery mineralocorticoid receptor (MR) antagonists were used in patients with small APA in greater percentage than patients with bigger adenomas (64 vs 30%, respectively, p=0.037). At follow up, blood pressure normalized in 63% of subjects. Recovered patients had a shorter duration of hypertension (p=0.038), and a smaller adenoma size (p=0.035). ROC curves showed that a duration of hypertension 6 years and APA size < 20 mm were the best predictors for blood pressure normalization. Patients with APA <20 mm showed the complete restoration of blood pressure circadian rhythm. Conclusions: The presence of APA <20 mm, duration of hypertension equal or shorter than 6 years and preoperative MR antagonists use are favourable prognostic factors for hypertension recovery after adrenalectomy. 2
Page 3 of 23 Introduction Conn first described primary aldosteronism (PA), a syndrome characterized by drug-resistant hypertension, suppressed plasma renin activity, excessive secretion of aldosterone and hypokalemia (1). Although previously thought to be a rarity, primary aldosteronism is now considered one of the most common causes of secondary hypertension: recent evidences show indeed, a PA prevalence of 10% among hypertensives and an aldosterone producing adenoma (APA) prevalence of 5 % (2-3). In the last few years several studies highlighted the negative effects of aldosterone excess on heart, blood vessels, kidney and brain (4-5), as well as on glucose metabolism and insulin sensitivity (6-7), indicating the need for a prompt diagnosis of primary aldosteronism and a correct therapeutic approach. While the treatment of choice for aldosterone producing adenoma is unilateral adrenalectomy (8-9), medical therapy is the best treatment for idiopathic hyperaldosteronism due to adrenal hyperplasia (IHA) (9-11). Laparoscopic adrenalectomy has become the treatment of choice and has replaced open surgery for treating benign adrenal tumours, since the first laparoscopic adrenalectomies were performed in 1992 by Gagner (12), Suzuki (13) and Higashihara (14), and co-workers. The transperitoneal laparoscopic approach of an aldosteronoma has many benefits of minimally invasive surgery including decreased post operative pain, shortened hospitalization, more rapid convalescence, decrease in overall cost and decreased morbidity with the smaller incisions and shorter postoperative recovery time (15-16). Although it is well demonstrated in the literature that adrenalectomy is beneficial for aldosterone producing adenoma, long-term outcome after surgery has not been extensively studied: in some cases hypertension persists even if adenoma has been completely removed and several investigators reported that long term normalization rate of blood pressure after surgery is no more than 30-70% of the cases (17-19). Numerous factors have been proposed as predictive factors for hypertension recovering, including age at surgery, response to spironolactone, blood pressure levels on discharge (20), duration of hypertension, family history for hypertension, preoperative ratio of plasma aldosterone to plasma renin activity (21), renal damage (22), serum potassium levels, sex (23), vascular remodelling (24). 3
Page 4 of 23 Aim of our study is to elucidate blood pressure long term outcome in patients undergoing laparoscopic adrenalectomy for aldosterone producing adenoma, in an attempt to identify new prognostic factors favourably correlated to blood pressure normalization after successful surgery. Subjects and methods: Study population Forty-two consecutive patients with confirmed primary aldosteronism due to an aldosterone producing adenoma have been enrolled in this study, after written informed consent. Patients referred to our clinic for suspicion of PA and adrenal mass were studied on an inpatient basis. All patients consumed a standard hospital diet, with a daily salt intake of 150mEq/ day, and a potassium intake of 50 75mEq/day. After hospital admission, both at baseline and at follow-up examinations, office blood pressure was measured in seated subjects, who had been quiet for at least 10 minutes, using a standard mercury sphygmomanometer with the cuff at the level of the heart and with cuff sizes selected on the basis of the measurement of arm circumference. The average of three reading obtained at 1-min intervals was considered for the study. Basal and dynamic evaluation was performed after discontinuation of any antihypertensive treatment for at least 4 weeks, except for calcium channel and alpha-blockers when required, which were withdrawn at hospital admission. Patients with hypokalemia (plasma potassium < 3.5 meq/l) had been given adequate oral or intravenous potassium supplements before the hormonal evaluations. The diagnosis of PA was established as previously described (25). Briefly PA was suspected for an upright serum aldosterone/upright PRA ratio (ARR) greater than 40 [(ng/dl) per (ng/ml per h)], together with an upright aldosterone value greater than 15 ng/dl, and confirmed with an intravenous 4-h saline infusion (2 l of 0.9% NaCl solution) which was considered positive if the post-test aldosterone value was greater than 7 ng/dl (25). In all patients with confirmed PA, differentiation between an adrenal adenoma and idiopathic aldosteronism was obtained using computerized tomographic (CT) scan of the adrenal glands with 3-mm contiguous slices after administration of a non-ionic iodinated contrast agent (n=37), or magnetic resonance imaging (MRI) in patients with iodine allergy or claustrophobia (n=5), followed by adrenal vein sampling 4
Page 5 of 23 (AVS) for measurement of aldosterone and cortisol (n=26); or dexamethasone-suppressed adrenal scintigraphy with I 131 cholesterol (n=16). The correct cannulation of adrenal veins and lateralization of aldosterone hypersecretion were defined according to the criteria proposed by Rossi et al (26). Due to the lack of cannulation of adrenal veins, AVS was successfully repeated in 8 patients. In all our patients with a CT scan or MRI showing a unilateral solitary adrenal nodule and a normalappearing controlateral adrenal gland we demonstrated a lateralization of aldosterone overproduction through AVS or adrenal dexamethasone-suppressed scintigraphy. Data about a history of essential hypertension in first-degree relatives and adenoma size at morphological evaluation were also collected. All patients underwent laparoscopic unilateral adrenalectomy performed by a surgical team with wide experience in abdominal laparoscopy. Patients were operated in the supine positions with no intraoperative complications or mortality; conversion to open surgery was never necessary; post operative pain was minimal and patients were able to ambulate 12-24h after surgery and were allowed liquid diet on the first day after it. The diagnosis of adenoma was further confirmed at surgery and pathological evaluation in all 42 APA. From May 2005 to December 2007 a within-subjects and longitudinal comparison was carried out after a mean follow-up period of 2.7±2.2 yrs (range between 9 months and 8 years) from laparoscopic adrenalectomy. The preoperative diagnosis of APA was confirmed post surgery by the satisfaction of all the following conditions, in all patients: 1) histopathological demonstration of cortical adrenal adenoma, 2) normalization of the renin-angiotensin-aldosterone system and of hypokalemia if present, 3) cure or improvement of hypertension. Hypertension was considered cured for blood pressure levels below 140/90 mmhg without any antihypertensive medications, while was considered improved when achievement of normal blood pressure was obtained with a reduced number of drugs, compared with the preoperative number. 5
Page 6 of 23 APA patients who remained hypertensive after surgery were re-evaluated at follow-up after discontinuation of antihypertensive treatment for at least 4 weeks, (except for calcium channel and alpha-blockers when required). Ambulatory blood pressure measurements Ambulatory blood pressure monitoring (ABPM) was performed in all subjects before and after surgery with Takeda TM-2430 instrument (A&D, Tokyo, Japan) using oscillometric measurements, at diagnosis and at follow-up. For the blood pressure analyses, daytime was defined as 0700 2259 h, and night-time from 2300 0659 h. Measurements were taken every 15 min during the daytime and every 30 min at night. Blood pressure thresholds were defined according to the European Society of Hypertension guidelines (27). Individual patient s blood pressure was classified in normal: blood pressure below 140/90mmHg, and hypertensives higher than 140/90mmHg or subject using antihypertensive drugs. The ABPM was considered normal if mean 24h blood pressure was below 125/80mmHg, diurnal mean blood pressure below 130/85mmHg and nocturnal mean blood pressure below 120/75mmHg. These parameters are important to avoid the white coat effect, to reveal masked hypertension and to classified subject as dipper or non dipper. Dippers were defined as individuals whose night-time blood pressures dropped more than 10% compared with their daytime blood pressures. Biochemical and hormonal assays All assays were performed in the Central Laboratory. Serum aldosterone (reference range for upright values, 4 31 ng/dl) was measured by a solid phase radioimmunoassay (RIA) kit (Biodata Diagnostics, Rome, Italy). PRA (reference range in the upright position, 1.5 5.7 ng/ml per h) was measured as the generation of angiotensin I in vitro using a commercially available RIA kit (Radim, Rome, Italy). Creatinine (reference range, 0.6 1.4mg/dl), was determined by standard procedures. Statistical analysis Statistical analysis was performed using the StatView version 4.1 software for PC (Abacus Concepts Inc., Berkley, California, USA), in collaboration with the Department of Statistics of Università Politecnica delle 6
Page 7 of 23 Marche. Data are expressed as a mean± standard deviation (SD) or median (25 th -75 th percentile) when appropriate. Statistical significance between groups at baseline was assessed by unpaired t test and a paired t test was used to compare treatment related changes within groups. The Mann Whitney test was used for data that did not follow a normal distribution. The Pearson X2-test was used to compare categorical variables. Data were analysed by analysis of variance test for multiple comparisons, as appropriate. The relationship between different variables was examined by linear regression analysis. Multivariate logistic regression analysis was then performed to identify variables independently associated with resolution of hypertension after adrenalectomy. Collinearity testing was used in order to exclude from the model variables that were interdependent. Observed differences with P<0.05 were considered statistically significant. Moreover, receiver operating characteristic (ROC) curve analysis was used to choose the best predictor for blood pressure normalization after surgery (i.e. the value with the maximum sensitivity and minimal loss of specificity). Results Baseline characteristics Clinical characteristics of our 42 patients with APA, divided according to gender, are shown in Table 1. The mean age of all patients was 50±11 years; females were significantly younger than males (p=0.040). Males showed a BMI significant higher than women (p=0.029); no significant differences for systolic and diastolic blood pressure levels were observed. The duration of known hypertension showed a significant difference between males and females (p=0.030) being longer in males. In 14 patients (33%) no family history for hypertension was reported. High plasma aldosterone levels and low or undetectable plasma renin activity were reported in all patients; ARR was greater than 40 without any difference between males and females. Hypokalemia was present in 19 out of 42 patients (45%), with an average value of 3.35 meq/l. Creatinine serum levels were higher in males than in females (p=0.001). The mean number of drugs used before hospital admission was 2.1±0.9 and 50% of patients received a mineralocorticoid receptor antagonist (MR blocker). 7
Page 8 of 23 The 24h blood pressure registration showed the loss of physiological circadian rhythm (systolic diurnal mean: 144±17mmHg, diastolic diurnal mean: 86±12mmHg; systolic nocturnal mean: 139±21, diastolic nocturnal mean: 81±11mmHg). Twenty patients presented with an adenoma of the right adrenal gland (48%), while 22 patients had an adenoma in the left adrenal (52%); mean adenoma size determined through imaging techniques was 21±9 mm (range between 8 mm and 48 mm). No significant differences were observed between males/females as for dimension (21±11 mm for males and 22±8 mm for females) and localization (males: 38% right adrenal and 62% left adrenal; females: 59% right adrenal and 41% left adrenal). Compared with patients whose adenoma was 20 mm of diameter, patients presenting with an adenoma less than 20 mm of size showed higher upright serum aldosterone levels (63±20 vs 38±17 ng/dl, p=0.009), higher aldosterone postsaline infusion values (23±12 vs 12±3 ng/dl, p=0.0001) and lower plasma potassium levels (3.22±0.13 vs 3.48±0.25 meq/l, p=0.020) (Figure 1). According to adenoma size, there were no significant differences regarding: systolic blood pressure (157±25 vs 154±23 mmhg), diastolic blood pressure (102±16 vs 98±13 mmhg) and duration of hypertension (8.4±6.4 vs 8.3±4.7 yrs). Patients with a smaller adenoma used, before surgery, MR blockers in greater percentage than patients with adenoma 20 mm of diameter: 14 subjects with adenoma less than 20 mm used MR antagonists (64%) and only 6 with adenoma 20 mm (30%) (p=0.037). Linear regression analysis showed that adenoma size was inversely correlated with upright aldosterone levels (r 2 : 0.119 p=0.003) and postsaline aldosterone (r 2 : 0,145 p=0.01) and directly correlated with plasma potassium levels (r 2 : 0.173, p=0.01). No correlation was observed between tumor size and duration of hypertension. Multiple regression analysis showed that the correlation remained significant for both post-saline aldosterone (p=0.03) and plasma potassium levels (p=0.01). Outcome of adrenalectomy and favorable prognostic factors All patients underwent unilateral laparoscopic adrenalectomy. At follow up evaluation (mean follow-up 2.7±2.2 years, range between 6 months and 8 years) all patients showed a normalization of aldosterone (51.1±33 vs. 18.4 ±15.6 ng/dl, p=0.0001) and PRA levels (0.43±0.29 vs 2.5±2.9 ng/ml per h, p=0.004) as well as of serum potassium levels (3.35±0.44 vs 4.3±0.68 meq/l, p<0.0001). Twenty-six patients out of 42 (63%) recovered from hypertension. Forty-six percent of patients were females and 54% males. Blood 8
Page 9 of 23 pressure levels improved in all remaining patients (Table 2). Nearly 70% (n=11) of our patients who remained hypertensive after surgery had a family history positive for hypertension. Table 3 shows patients preadrenalectomy data stratified by blood pressure outcome post surgery: patients who remained hypertensive used a mean of 2 drugs (2.2 ±0.7) similarly to recovered patients (2 ±1.1). Fifty percent of patients used MR blockers: 61% of them recovered and 25% remained hypertensive after surgery (p=0.029). Moreover, a significant difference as for duration of hypertension was observed: recovered patients had a shorter duration of hypertension than patients who remained hypertensive (10.3 ±5.1 vs. 6.9 ±4.9 yrs, p=0.038). Adenoma size was smaller in recovering patients (18 ±9 vs 24 ±8 mm, p=0.035) (Table 3). Considering gender differences, as previously stated, females had significantly shorter duration of hypertension and, although the difference was not significant, recovered more often than males (67% vs 58%, p=n.s.). Recovered females (n=18) used less drugs (1.8±1.0 vs 2.6 ±0.5, ), and had a smaller adenoma (18 ±6 vs 28 ±9 mm, p=0.012). Recovered males (n=24) had slightly smaller adenoma size compared with patients who remained hypertensive (18 ±11 vs 21 ±8 mm, p=n.s.) No differences were observed for number of drugs used before surgery in recovered/not recovered males (2.3±1.2 vs 2±0.8, respectively). Without reaching statistical significance, both, recovered males and females, had shorter duration of hypertension compared with hypertensives: in females 5.8 ±4.3 vs 8.4 ±4.2 years and in males 8.2 ±5.7 vs 11.3 ±6.4 years. Considering tumor size, patients with adenoma smaller than 20 mm of diameter showed after surgery a significant reduction of both diurnal and nocturnal, systolic and diastolic blood pressure values, and the complete restoration of blood pressure circadian rhythm. Although an improvement of blood pressure levels was observed, no significant differences were found in patients carrying an adenoma bigger than 20 mm (Table 4). ROC curve analysis showed that among the continuous variables correlated with resolution of hypertension after adrenalectomy, the best predictors for blood pressure normalization were: duration of hypertension 6 years (sensitivity=67%, specificity 71%) and adenoma size < 20 mm (sensitivity 81%, specificity 52%) (Figure 2). 9
Page 10 of 23 Discussion This study evaluated the cure rate of primary aldosteronism due to aldosterone producing adenoma (APA) and identified prognostic factors of recovering after unilateral laparoscopic adrenalectomy. The primary goals of APA treatment are correction of the biochemical features of primary aldosteronism and improvement, if not complete resolution, of hypertension. In the present study, surgical management of APA led to normalization of serum potassium levels and set aldosterone and PRA levels within the normal range, in all patients. Moreover, 63% of our APA patients were cured of hypertension (blood pressure below 140/90 mmhg, without the aid of antihypertensive medications), while blood pressure levels improved in the remaining patients. Such results are in line with literature data reporting a rate of blood pressure normalization ranging between 30 and 70% (19, 24). This broad range comes from studies performed with different data collection methods and with different definition of cure/improvement of hypertension (18, 19, 21, 28). Considering predictors of outcome of adrenalectomy, we observed that in our patients the cure of hypertension after surgery was associated with a shorter duration of hypertension, pre-surgery treatment with MR antagonists and adenoma size smaller than 20 mm, but not with other factors previously reported to be associated with a favourable blood pressure outcome such as age, sex, BMI, aldosterone levels, number of antihypertensive agents, family history of hypertension (28, 18-20). In agreement with previous studies (18, 19, 24), in our group of patients duration of hypertension, can be considered a prognostic factor: shorter hypertension duration gives indeed, a higher recovery percentage. In particular, the ROC curve analysis showed that the best predictor for hypertension recovery after surgery is duration of hypertension equal or shorter than 6 years, in accordance with a recent study by Zarnegar et al. (18). To this regard, we can hypothesize that aldosterone excess for long time could induce detrimental and irreversible effects on the cardiovascular system, such as cardiac fibrosis, left ventricular hypertrophy (29-31) or vascular remodelling with increased intima-media thickness (24), responsible for hypertension persistence in spite of aldosterone normalization after surgery. 10
Page 11 of 23 On the other hand, longer hypertension history is often present in older patients, so hypertension s maintenance could also depend on the onset of essential hypertension that can not be cured by adrenal surgery. Although females recovered slightly more often than males in our population, the first were younger than males, their BMI was lower and, more importantly, their hypertension was lasting less. Before surgery there were no differences as for the number of medications used by men and women. However, recovered women used fewer drugs than those who remained hypertensive and, noteworthy MR antagonists were used in a larger percentage in these women. This is a possible demonstration that the targeted action of this drug can counteract aldosterone excess. In our patients the use of MR antagonists per se appears to be significantly predictive of hypertension recovering. At variance with other studies reporting the preoperative use of spironolactone as MR antagonist (32-33) this compound was not used in any of our patients because of its known anti-androgenic side effects. Therefore, canrenone or potassium canrenoate was preferred. In our cohort this treatment appears to be of prognostic value for blood pressure normalization after surgery. In fact, in more than two thirds of patients taking MR antagonists, normalization of blood pressure levels after adrenalectomy was observed. However, it is equally plausible that the association between MR antagonists use and post operative cure of hypertension is indeed due to the fact that small APA, being more active, have been treated more frequently with MR antagonists. Pre-surgery levels of aldosterone have been proposed as an unfavourable prognostic factor for hypertension recovery (34): the highest levels correlated with hypertension persistence. However, in the present study, as well as in Fukudome s (22), there was no correlation between aldosterone levels before surgery and persistence of hypertension. Interestingly, in our patients a significant inverse correlation between the size of the adenoma and aldosterone levels was observed, both for upright and post saline infusion aldosterone, while adenoma dimensions directly correlated with serum potassium levels. These observations highlight that small adenomas (i.e. adenomas with diameter less than 20 mm) seem to be characterized by a more pronounced aldosterone secretion, compared with bigger ones. Interestingly, the presence of an aldosterone producing adenoma smaller than 20 mm was also a predictor of hypertension recovery after surgery, as shown also by 11
Page 12 of 23 the ROC analysis. Recently, similar results have been found by Omura et al. (35) who reported that hypertension cure rate was higher in patients with micro adenoma. However, at variance with Omura s and colleagues, who found that micro adenomas were less active (lower aldosterone levels, lower ARR and higher potassium levels), in our study small APA are characterized by a more pronounced aldosterone secretion. In this regard it s important to underline that in Omura s paper the presence of a micro adenoma was defined at pathology for adenomas with a diameter of less than 7 mm, however, considering our cut-off (i.e. diameter of 20 mm), 86% of their patients had an adenoma smaller than 20 mm so it s clear that it s quite difficult to compare the results of these two papers. It is possible to speculate that smaller adenomas are characterized by a more marked aldosterone secretion, which removal, in the presence of an early diagnosis, is more likely related to primary aldosteronism cure. In this view, the histopathological examination of removed APA would be extremely helpful in order to look for specific characteristic of the adrenal gland in relation to the adenoma dimensions, to see if adenomas bigger than 20 mm present themselves aspects of hyperplasia or if adjacent areas appear to be hyperplastic. It could be hypothesized, indeed that bigger adenomas present hyperplastic aspects that from a clinical point of view correspond to a less marked aldosterone hypersecretion, with a less evident picture of primary aldosteronism, and therefore not diagnosed for a long period with subsequent organ damages responsible, in the end, for the persistence of hypertension after adrenalectomy. It is noteworthy that in the present study we found that small adenomas were responsible for higher aldosterone levels (both in the upright position and postsaline) and for lower serum potassium levels compared with adenoma bigger or equal to 20 mm of diameter. In addition, our results showed that the presence of a small adenoma defines patients with a better response of blood pressure levels also in terms of recovery of the circadian rhythm, evaluated with the ambulatory blood pressure measurements. It is well known, indeed that patients with primary aldosteronism loose blood pressure circadian rhythm and become non dipper, condition associated to an increased risk for cardiovascular events (36-37). In our patients 24h blood pressure monitoring showed that after surgery patients with small adenoma restored blood pressure circadian rhythm at variance with patients with a bigger adenoma. 12
Page 13 of 23 In conclusion, in order to avoid inappropriate and prolonged therapy and to prevent irreversible organ damage, an early and correct diagnosis of APA is mandatory, as in a high percentage of cases diagnosis means recovery. Our results confirm indeed, that adrenalectomy can be performed safely and, in the majority of patients with aldosterone producing adenoma, with good outcomes leading to hypertension resolution in nearly two thirds of cases, especially when hypertension is treated with specific drugs such as MR antagonists, concomitant essential hypertension is absent, patients have a short history of hypertension and, as observed in the present study for the first time, the adenoma is of small size. Therefore, duration of hypertension of or shorter than six years, preoperative MR antagonists use and the presence of an adrenal adenoma smaller than 20 mm, represent favourable prognostic factors for hypertension recovering after surgical removal of aldosterone producing adenoma. Disclosure The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported. This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector. References 1. Conn JW. Presidential Address. Part II. Primary aldosteronism, a new clinical syndrome. Journal of Laboratory and Clinical Medicine 1955 45 3-17. 2. Rossi GP, Bernini G, Caliumi C Desideri G, Fabris B, Ferri C, Ganzaroli C, Giacchetti G, Letizia C, Maccario M, Mallamaci F, Mannelli M, Mattarello MJ, Moretti A, Palumbo G, Parenti G, Porteri E, Semplicini A, Rizzoni D, Rossi E, Boscaro M, Pessina AC & Mantero F; PAPY Study Investigators. A prospective study of the prevalence of primary aldosteronism in 1,125 hypertensive patients. Journal of American College of Cardiology 2006 48 2293-300. 3. Mulatero P, Stowasser M, Loh KC, Fardella CE, Gordon RD, Mosso L, Gomez-Sanchez CE, Veglio F & Young WF Jr. Increased diagnosis of primary aldosteronism including surgically correctable 13
Page 14 of 23 forms, in centers from five continents. Journal of Clinical Endocrinology and Metabolism 2004 89 1045 1050. 4. White PC. Aldosterone: direct effects on and production by the heart. Journal of Clinical Endocrinology and Metabolism 2003 88 2376 2383. 5. Rossi GP, Boscaro M, Ronconi V & Funder JW. Aldosterone as a cardiovascular risk factor. Trends in Endocrinology and Metabolism 2005 16 104 107. 6. Corry DB & Tuck ML. The effect of aldosterone on glucose metabolism. Current Hypertension Reports 2003 5 106 109. 7. Giacchetti G, Sechi LA, Rilli S & Carey RM. The renin-angiotensin aldosterone system, glucose metabolism and diabetes. Trends in Endocrinology and Metabolism 2005 16 120 126. 8. Young WF Jr & Klee GG. Primary aldosteronism. Diagnostic evaluation. Endocrinology Metabolism Clinics of North America 1988 17 367 395. 9. Funder JW, Carey RM, Fardella C, Gomez-Sanchez CE, Mantero F, Stowasser M, Young JW Jr & Montori VM. Case detection, diagnosis, and treatment of patients with primary aldosteronism: an Endocrine Society clinical practice guideline. Journal of Clinical Endocrinology and Metabolism 2008 93 3266-3281. 10. Grant CS, Carpenter P, van Heerden JA & Hamberger B. Primary aldosteronism. Clinical management. Archives of Surgery 1984 119 585-590. 11. Young WF Jr, Hogan MJ, Klee GG, Grant CS & van Heerden JA. Primary aldosteronism: diagnosis and treatment. Mayo Clinic Proceedings 1990 65 96-110. 12. Gagner M, Lacroix A & Bolte E. Laparoscopic adrenalectomy in Cushing s syndrome and phaeochromocytoma. New England Journal of Medicine 1992 327 1033. 13. Suzuki K & Kawabe K. Laparoscopic adrenalectomy. Urology Surgery 1992 5 753-757. 14. Higashihara E, Tanaka Y, Horie S, Aruga S, Nutahara K, Homma Y, Minowada S & Aso Y. A case report of laparoscopic adrenalectomy. Nippon Hinyokika Gakkai Zasshi 1992 83 1130-1133. 15. Shen WT, Lim RC, Siperstein AE, Clark OH, Schecter WP, Hunt TK, Horn JK & Duh QY. Laparoscopic vs open adrenalectomy for the treatment of primary hyperaldosteronism. Archives of Surgery 1999 134 628 632. 14
Page 15 of 23 16. Tan YH, Yip SK, Chee C & Cheng CW. Comparison of laparoscopic and open adrenalectomy a Singapore experience. Asian Journal of Surgery 2002 25 330 334. 17. Blumenfeld JD, Sealey JE, Schlulssel Y, Vaughan ED Jr, Sos TA, Atlas SA, Muller FB, Acevedo R, Ulick S & Laragh JH. Diagnosis and treatment of primary aldosteronism. Annals of Internal Medicine 1994 121 877 885. 18. Zarnegar R, Young WF Jr, Lee J, Sweet MP, Kebebew E, Farley DR, Thompson GB, Grant CS, Clark OH & Duh QY. The aldosteronoma resolution score. Predicting complete resolution of hypertension after adrenalectomy for aldosteronoma. Annals of Surgery 2008 247 511-518. 19. Plouin PF, Rossignol P & Amar L. Selection of patients for surgery for primary aldosteronism. Clinical and Experimental Pharmacology and Physiology 2008 35 522-525. 20. Lo Cy, Tam PC, Kung AW, Lam KS & Wong J. Primary aldosteronism. Results of surgical treatment. Annals of Surgery 1996 224 125-130. 21. Sawka AM, Young WF Jr, Thompson GB, Grant CS, Farley DR, Leibson C & van Heerden JA. Primary aldosteronism: factors associated with normalization of blood pressure after surgery. Annals of Internal Medicine 2001 135 258-261. 22. Fukudome Y, Fujii K, Arima H, Ohya Y, Tsuchihashi T, Abe I & Fujishima M. Discriminating factors for recurrent hypertension in patients with primary aldosteronism after adrenalectomy. Hypertension Research 2002 25 11-18. 23. Goh BK, Tan YH, Yip SK, Eng PH & Cheng CW. Outcome of patients undergoing laparoscopic adrenalectomy for primary hyperaldosteronism. Journal of the Society of Laparoendoscopic Surgeons 2004 80 320-325. 24. Rossi GP, Bolognesi M, Rizzoni D, Seccia TM, Piva A, Porteri E, Tiberio GAM, Giulini SM, Agabiti-Rosei E & Pessina AC. Vascular remodeling and duration of hypertension predict outcome of adrenalectomy in primary aldosteronism patients. Hypertension 2008 51 1366-1371. 25. Giacchetti G, Ronconi V, Lucarelli G, Boscaro M & Mantero F. Analysis of screening and confirmatory tests in the diagnosis of primary aldosteronism: need for a standardized protocol. Journal of Hypertension 2006 24 737 745. 15
Page 16 of 23 26. Rossi GP, Sacchetto A, Chiesura-Corona M, De Toni R, Gallina M, Feltrin GP & Pessina AC. Identification of the etiology of primary aldosteronism with adrenal vein sampling in patients with equivocal computer tomography and magnetic resonance findings: results in 104 consecutive cases. Journal of Clinical Endocrinology and Metabolism 2001 86 1083 1090. 27. Mancia G, De Backer G, Dominiczak A, Cifkova R, Fagard R, Germano G, Grassi G, Heagerty AM, Kjeldsen SE, Laurent S, Narkiewicz K, Ruilope L, Rynkiewicz A, Schmieder RE, Boudier HA & Zanchetti A; ESH-ESC Task Force on the Management of Arterial Hypertension. ESH-ESC Practice Guidelines for the Management of Arterial Hypertension: ESH-ESC Task Force on the Management of Arterial Hypertension. Journal of Hypertension 2007 25 1751-62. 28. Meyer A, Brabant G & Beherend M. Long term follow up after adrenalectomy for primary aldosteronism. World Journal of Surgery 2005 29 155-159. 29. Rossi GP, Di Bello V, Ganzaroli C, Sacchetto A, Cesari M, Bestini A, Giorgi D, Scognamiglio R, Mariani M & Pessina AC. Excess aldosterone is associated with alterations of myocardial texture in primary aldosteronism. Hypertension 2002 40 23-27. 30. Giacchetti G, Ronconi V, Turchi F, Agostinelli L, Mantero F, Rilli S & Boscaro M. Aldosterone as a key mediator of the cardiometabolic syndrome in primary aldosteronism: an observational study. Journal of Hypertension 2007 25 177 186. 31. Rossi GP, Sechi LA, Giacchetti G, Ronconi V, Strazzullo P & Funder JW. Primary aldosteronism: cardiovascular, renal and metabolic implications. Trends in Endocrinology and Metabolism 2008 19 88-90. 32. Ferriss JB, Brown JJ, Fraser R, Haywood E, Davies DL, Kay AW, Lever AF, Robertson JI, Owen K & Peart WS. Results of adrenal surgery in patients with hypertension, aldosterone excess, and low plasma renin concentration. British Medical Journal 1975 1 135-8. 33. Zarnegar R, Lee J, Brunaud L, Lindsay S, Kebebew E, Clark OH & Duh QY. Good blood pressure control on antihypertensives, not only response to spironolactone, predicts improved outcome after adrenalectomy for aldosteronoma. Surgery 2007 142 921-9. 34. Gockel I, Heintz A, Polta M & Junginger T. Long-term results of endoscopic adrenalectomy for Conn s syndrome. The American Surgeon 2007 73 174-80. 16
Page 17 of 23 35. Omura M, Sasano H, Saito J, Yamaguchi K, Kakuta Y & Nishikiwa T. Clinical characteristics of aldosterone-producing micro adenoma, macro adenoma and idiopathic hyperaldosteronism in 93 patients with primary aldosteronism. Hypertension Research 2006 29 883-889. 36. Giles TD. Circadian rhythm of blood pressure and the relation to cardiovascular events. Journal of Hypertension Supplement 2006 24 S11-16. 37. Liu M, Takahashi H, Morita Y, Maruyama S, Mizuno M, Yuzawa Y, Watanabe M, Toriyama T, Kawahara H & Matsuo S. Non-dipping is a potent predictor of cardiovascular mortality and is associated with autonomic dysfunction in haemodialysis patients. Nephrology Dialysis Transplantation 2003 18 563-569. 17
Page 18 of 23
Page 19 of 23
Page 20 of 23 Table1 Baseline characteristics of studied patients Total F M p Patients (n) 42 18 24 Age (yrs) 50±11 46±10 53±11 p=0.040 Family History for hypertension (n) 28 12 16 Years since hypertension 8.3±5.6 6.2±4.1 9.8±5.8 p=0.030 Drugs used (n) 2.1 ±0.9 2.0 ±0.9 2.1 ±1.0 BMI (kg/mq) 26.9±3.3 25.6±3.6 27.8±2.7 p=0.029 SBP (mmhg) 156±24 152±21 159±25 DBP (mmhg) 100±15 99±13 101±16 Na+ (meq/l) 143±2.4 142±2.7 143±2.1 K+ (meq/l) 3.35±0.44 3.37±0.48 3.37±0.40 UNa + (meq/24h) 152±60.8 152.9±60.8 151.5±66.4 UK + (meq/24h) 54.4±17.3 51.3±16.1 57.4±18.3 Creatinine (mg/dl) 0.93±0.25 0.76±0.17 1.1±0.2 p=0.001 PRA (ng/ml/h) 0.3 (0.2-0.6) 0.3 (0.2-0.6) 0.3 (0.2-0.7) Aldosterone (ng/dl) 51.1±32.9 44.7±15.4 56.5±42.3 ARR 105 (67-186) 103 (73-171) 108 (55-223) Postsaline aldosterone (ng/dl) 17.1±11.1 18.8±12.4 15.9±10.2
Page 21 of 23 Table 2 Postadrenalectomy anthropometric and clinical features of studied patients according to blood pressure outcome Cured (n=26)(63%) Improved (n=16)(37%) p Sex, F/M (n) 12/14 6/10 BMI (kg/mq) 27±4 28±5 SBP (mmhg) 129±16 149±8 p=0.0001 DBP (mmhg) 77±10 88±11 p=0.0001 Na+(mEq/l) 143±3 141±2.1 K+(mEq/l) 4.25±0.64 4.10±0.50 Creatinine (mg/dl) 1.1±0.40 1.02±0.22 PRA (ng/ml/h) 2.9 (1.0-2.4) 1.7 (1.3-4.0) Aldosterone (ng/dl) 18.5±19.2 20.2±6.4
Page 22 of 23 Table 3 Preadrenalectomy anthropometric and clinical features of studied patients according to blood pressure outcome Cured (n=26) (63%) Improved (n=16)( 37%) p Age (yrs) BMI (kg/mq) 48±11 53±11 27±2.9 SBP (mmhg) 153±20 159±28 DBP (mmhg) 99±12 101±17 Na+ (meq/l) 143±2.7 143±2 K+ (meq/l) 3.27±0.45 3.44±0.41 Creatinine(mg/dl) 0.90±0.25 0.95±0.25 PRA (ng/ml/h) 0.3 (0.2-0.4) 0.4 (0.2-0.8) Aldosterone (ng/dl) 51.3±31 50.9±36 Postsaline aldosterone (ng/dl) 17.4±11.4 16.8±11 Family history for hypertension (n) 15 11 Drugs (n) 2.0 ±1.1 2.3 ±0.7 Use of MR antagonists* % (n) 61% (16) 25% (4) p=0.029 Years since hypertension 6.9 ±4.9 10.3 ±5.1 p=0.038 Adenoma size (mm) 18 ±9 24 ±8 p=0.035
Page 23 of 23 Table 4 Effects of adrenalectomy on ambulatory blood pressure monitoring results according to adenoma size Adrenal Adenoma < 20 mm (n=22) Adrenal Adenoma > 20 mm (n=20) Before Surgery Post Surgery p Before Surgery Post Surgery p Diurnal SBP (mmhg) 146±12 135±11 p<0.0001 146±18 142±13 Diurnal DBP (mmhg) 88±11 77±7 p=0.0001 88±13 85±12 Nocturnal SBP (mmhg) 140±18 123±14 p=0.0001 136±16 130±26 Nocturnal DBP (mmhg) 81±10 72±7 p=0.0020 79±11 77±16