Long-term trends in treatment and outcomes of patients with diabetes and acute coronary syndromes: insights from the nationwide AMIS plus registry

Background

Although impressive advances in the treatment of patients with acute coronary syndromes (ACS) have been achieved over the last decades, morbidity and mortality of patients with diabetes and ACS remain substantial. This study aimed at investigating long-term trends in treatment and outcomes of patients with diabetes and ACS, using data from a large, prospective, nation-wide database.

Methods

Patients with ST segment elevation myocardial infarction (STEMI) or non-ST segment elevation myocardial infarction (NSTEMI) enrolled in the prospective AMIS Plus registry between 01/2003 and 12/2018 and available data on diabetes diagnosis were included in the analysis. Major adverse cardiovascular events (MACE), a composite of all-cause death, non-fatal myocardial infarction, and cerebrovascular events were assessed for each 3-year period.

Results

Out of 49'413 ACS patients, 10'200 (20.6%) had diabetes (29.4% women). In diabetic patients, the percentage of women decreased from 32.3% in 2002–2004 to 25.9% in 2017–2019 (p<0.001). Diabetic patients were older (p<0.001), more frequently women (p<0.001), and had a higher body mass index (p<0.001). They less often underwent percutaneous coronary intervention (p<0.001) and were more frequently treated by coronary artery bypass grafting (p<0.001). Over the 18-year period, the percentage of diabetic patients undergoing PCI or CABG increased (p<0.001). While treatment with glycoprotein IIb/IIIa inhibitors, low-molecular weight heparin, and beta blockers decreased over time, administration of aspirin, P2Y12 inhibitors, lipid-lowering drugs, and unfractionated heparin increased. Rates of MACE were 9.5% and 5.2% in diabetic and non-diabetic patients (p<0.001). Rates of mortality (7.7% versus 4.1%, p<0.001), recurrent myocardial infarction (1.5% versus 0.9%, p<0.001), and cerebrovascular events (1.2% versus 0.6%, p<0.001) were higher in diabetic as compared with non-diabetic patients, with highest rates of MACE, mortality, and myocardial infarction observed in diabetic women. Rates of MACE decreased from 11.8% in 2002–2004 to 7.5% in 2017–2019 in diabetic patients (p for trend <0.001). While rates of mortality (9.4% to 5.9%, p for trend =0.001) and rates of recurrent myocardial infarction (3.4% to 0.9%, p for trend <0.001) decreased over time, rates of cerebrovascular events remained stable (p for trend =0.34). Trends were the same in diabetic women and men.

Conclusions

Rates of MACE significantly decreased over the 18-year period in both diabetic women and men, with highest rates observed in diabetic women. Despite the observed improvements, rates of MACE remained 50% higher in diabetic as compared with non-diabetic patients. These findings emphasize that advanced strategies particularly targeting the vulnerable high-risk diabetic patient population are warranted to further improve quality of care in ACS.

Funding Acknowledgement

Type of funding sources: None.

Temporal trends in treatment and outcomes of patients with acute coronary syndrome and concomitant moderate to severe renal failure

Introduction

Limited information about the management and outcomes of patients with acute coronary syndromes (ACS) and moderate to severe renal failure (RF) is available owing to underrepresentation of this population in most studies.

Methods

We evaluated the use of guideline-recommended therapies and in-hospital outcomes of totally 49'191 ACS patients with normal-mild renal failure (RF) (defined as eGFR >45ml/min/m2) versus moderate-severe RF (eGFR <45ml/min/m2) enrolled in the prospective Acute Myocardial Infarction in Switzerland (AMIS) cohort between 2002 and 2019 according to 2-year periods.

Results

Overall, 3'478 (7.1%) patients had moderate-severe RF. They were older (65.2+12.9 versus 77.2+10.6 years) and had significantly more comorbidities (including heart failure, cerebrovascular and peripheral vascular disease). Moderate-severe RF patients received less frequently guideline-recommended drugs, including P2Y12 inhibitors, ACEI/ARBs and statins (p<0.0001). Between the first and last 2-year periods, the number of patients with moderate-severe RF and number of performed percutaneous coronary interventions (PCI) increased in this cohort (p-for-trend=0.001). At the same time, in-hospital mortality significantly decreased among ACS patients with and without RF (17.5% to 10.5% and 6.0% to 3.9%, respectively, p-for-trend=0.001 for both, see Figure). Similar trends were observed for other complications, namely cardiogenic shock and reinfarction. However, major bleedings increased significantly over time in patients with and without RF (p-for-trend=0.038 and <0.001, respectively).

Conclusions

Outcomes of ACS patients with moderate to severe RF improved over the last two decades. Even though the rate of PCI increased in ACS patients with moderate-severe RF, they were less likely to receive guideline-recommended therapies and still suffer a high in-hospitality mortality (>10%). With respect to the increasing burden of ACS patients with RF, our study implicates that more efforts should be undertaken to further improve outcomes of those patients.

Funding Acknowledgement

Type of funding source: None

Delay between symptom onset and hospital admission in patients with ST-elevation myocardial infarction: different trends in men and women

Introduction

The aim of this study was to analyse whether prehospital delay in ST-elevation myocardial infarction (STEMI) has changed in men and women since 2002.

Methods

We used data from the AMIS Plus registry of patients who were admitted for STEMI between 2002 and 2019. Patients who were transferred from another hospital or were resuscitated before admission were excluded. Patient delay was defined as the difference between symptom onset and hospital admission time. Trends in delay according to gender were depicted by medians per year with a 95% confidence interval. Differences between men and women were tested using the Mann-Whitney test. To analyse the adjusted effect of gender on delay, multivariable quantile regression was applied including the interaction between gender and admission year as well as the covariates age, diabetes, pain at presentation and myocardial infarction (MI) history.

Results

Among the 15,154 patients included (74.5% men), the overall median (IQR) delay between 2002 and 2019 was 150 (84; 345) minutes for men and 180 (100; 415) for women. Women were older (71.3y vs. 62.8y, p<0.001), had more often diabetes (20.0% vs. 16.9%, p<0.001), but less often MI history (11.2% vs. 14.9%, p<0.001) and less often pain at presentation (92.0% vs. 94.8%, p<0.001).

The unadjusted median delay decreased over the admission years. The decreasing trend was stronger in women than men: the unadjusted difference in delay between men and women decreased from 60 min in 2002 (p=0.003) to 15 min in 2019 (p=0.155) (Fig 1). The multivariable model confirmed a significant interaction between gender and admission year (p=0.042) indicating that the decrease in delay was stronger for women (−3.1 min per year) than for men (−1.4 min per year) even after adjustment. The adjusted difference between men and women decreased from 27.4 min in 2002 to −1.6 min for women in 2019. Additional independent predictors of longer delay were the covariates age (+1.6 min per additional year, p<0.001) and diabetes (+27.1 min, p<0.001). Conversely, pain at admission (−46.3 min, p<0.001) and MI history (−32.9 min, p<0.001) predicted a shorter delay.

Conclusions

The difference in delay between symptom onset and hospital admission in STEMI patients between men and women steadily diminished from 2002 to 2019. This might indicate that the public and health professionals' awareness of STEMI in women has ameliorated over time.

Unadjusted delay according to gender

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): AMIS Plus Foundation

P4391Cardiovascular risk factor trends over two decades in patients presenting with acute myocardial infarction: a failure of smoking control, especially in women

Background

Hypertension, diabetes, dyslipidemia and smoking are established cardiovascular risk factors (CVRF). Little is known about the changes of risk factor profiles over time in patients presenting with acute myocardial infarction (AMI).

Purpose

To analyze the temporal trends of CVRF in patients presenting with AMI over the last 22 years in Switzerland.

Methods

We included data of all AMI patients enrolled between 1997 and 2018 in the Swiss nationwide AMIS Plus registry. The rates of hypertension, diabetes, dyslipidemia and smoking at presentation were descriptively analyzed dividing the data into 2-year periods. Trend analyses were performed using the CHI-square-test and ANOVA. A p-value of <0.005 was considered as statistically significant.

Results

A total of 57,995 patients were included in the analysis (73.6% male). The mean age was 66.0 years (males: 64.0 years, females 71.6 years) and did not differ over the study period. The mean CVRF rates over the study period were as follows: diabetes 20.5% (males: 19.4%, females: 23.6%), hypertension 60.2% (males: 57.0%, females: 69.0%), dyslipidemia 59.4% (males: 60.5%, females: 56.4%), and smoking 39.3% (males: 43.0%, females: 28.7%). While there was no significant change over time in the rates of diabetes for both genders, there were significant increases in the rates of hypertension and dyslipidemia for both males and females (p<0.001 for all comparisons). In terms of smoking, there was no significant trend for males while there was a significant increase in the rate of smoking for females (p<0.001). As a result, the gap in smoking rates between men and women decreased from 19.9% (45.3% vs. 25.4%) in 1997/98 to 7.9% (41.2% vs. 33.3%) in 2017/18.

Trends in the rate of smokers

Conclusions

Among patients presenting with AMI in Switzerland over two decades, the prevalence of hypertension and dyslipidemia increased in both men and women, while diabetes at presentation did not change over the years. We documented a failure of smoking control, with a lack of a reduction in the smoking prevalence among males and a striking increase among women.

P1876Atrial fibrillation related symptoms and cardiovascular outcomes

Background

Comprehensive information on the impact of atrial fibrillation (AF)-related symptoms and quality of life (QoL) on adverse outcomes is sparse.

Purpose

We aimed to investigate whether AF-related symptoms and/or QoL are associated with cardiovascular outcomes in a large cohort of AF patients.

Methods

A total of 3902 participants with documented AF from two nationwide prospective cohort studies in Switzerland were included. Information on AF-related symptoms was assessed yearly by standardized questionnaires, QoL was quantified using a visual analog scale (0–100, with higher scores indicating better QoL). The primary endpoint was a composite of stroke and systemic embolism. The secondary endpoint was a composite of cardiovascular death, hospitalization for heart failure and myocardial infarction. We assessed associations using multivariable, time-updated Cox proportional-hazards models including age, sex, study cohort, history of heart failure, hypertension, diabetes, prior stroke, prior myocardial infarction, vascular disease and prior catheter ablation for AF as covariates.

Results

Mean age was 72 years, and 72% were male. The median QoL score was 75 points, and 2572 (66%) participants had AF-related symptoms. Symptomatic individuals were younger (71 vs 75 years) and had more often paroxysmal AF (29 vs 23%) (p for both <0.001). The most frequent symptoms were palpitations (42%), dyspnea (25%) and fatigue (18%). In multivariable, time-updated models, the hazard ratio (HR) was 1.24 (95% confidence intervals (CI) 0.72; 2.11, p=0.43) for the primary endpoint and HR 0.83 (95% CI 0.65; 1.06, p=0.14) for the secondary endpoint in symptomatic vs non-symptomatic individuals. There was a significant, inverse association for a 5-point increase in the QoL score with both the primary (HR 0.94 (95% CI 0.88; 0.99), p=0.04) and secondary (HR 0.91 (95% CI 0.88; 0.93), p<0.0001) endpoints.

Conclusions

AF-related symptoms are not associated with adverse cardiovascular events in AF patients. In contrast, QoL is inversely associated with to adverse cardiovascular outcomes.

[A new beta 1-receptor blocker in the therapy of essential hypertension and angina pectoris]

In 242 patients with hypertension and/or angina pectoris, a new cardioselective betablocker without ISA, bisoprolol (Concor), was tested. The average mean value of 168/102 mm Hg was lowered in the 174 hypertensive patients by a systolic value of 17 and a diastolic value of 11 mm Hg. A normal diastolic pressure of 95 mm Hg or below was attained within 4 weeks in 73% of patients. Angina pectoris improved from 7 attacks per week before treatment to 3 attacks after 2 weeks; patients with additional hypertension showed a further improvement after another two weeks to an average of 1.7 attacks per week. Side effects were most frequently dizziness, headache and fatigue and also a few patients with gastrointestinal symptoms, an unusual side effect with this treatment. The results show the effective antihypertensive and antianginal action of bisoprolol in a large group of outpatients.

[The long-term course of 60 patients with alveolar echinococcosis in continuous therapy with mebendazole (1976-85)]

Since 1976 60 patients with inoperable alveolar echinococcosis caused by Echinococcus multilocularis were treated with high doses of mebendazole and examined at regular intervals prospectively according to our protocol regarding clinical course, liver function, morphology, immunologically and plasma mebendazole levels. The average duration of disease was 8(1-19) years, the average duration of chemotherapy was 4.25 (0.75-9) years. The long term results showed a correlation of the clinical course with the mean plasma mebendazole levels and the duration of chemotherapy, respectively. Death (n = 5) or transient progression of the disease process (n = 14) was observed primarily in patients with low plasma mebendazole levels in the early course and within the first two years of chemotherapy. Only 9 patients showed a decrease of the parasite mass. Immundiagnosis (total serum IgE and serum antibodies against Echinococcus antigen) gave some information with regard to therapy results, but only in the long-term course. The cumulative survival of the patients under study was 96% at 5 years and 84% at 10 years, respectively which is markedly higher compared to historical control series with a letality of greater than 90% within 10 years.

Travelers' diarrhea in West Africa and Mexico: fecal transport systems and liquid bismuth subsalicylate for self-therapy

The goals of this study were threefold: to compare the etiology of travelers' diarrhea in West Africa and Mexico, to evaluate two fecal transport systems for the recovery of enteropathogens, and to verify the efficacy of liquid bismuth subsalicylate (BSS) in different locations and under different entrance criteria for disease severity. The study populations consisted of 133 European tourists in West Africa and 112 American students in Mexico who had suffered from travelers' diarrhea. In 60% and 38% of the stool samples at the two study sites, similar proportions of enteropathogens were detected. A two-vial system consisting of Enteric Plus medium and polyvinyl alcohol fixative was slightly superior for identifying enteric pathogens than was a three-vial system with buffered glycerol saline, Cary-Blair medium with campylobacter antibodies, and polyvinyl alcohol fixative. In a parallel, double-blind, randomized trial, BSS significantly shortened disease duration at both study sites.

Sero-epidemiological survey for alveolar echinococcosis (by Em2-ELISA) of blood donors in an endemic area of Switzerland

Sera from 17,166 blood donors living in 10 cantons of northern Switzerland in an area endemic for Echinococcus multilocularis were investigated by serological survey for alveolar echinococcosis (AE). A highly species-specific antigen (Em2) and a commonly used E. granulosus hydatid fluid antigen (EgHF) were compared for their suitability in seroepidemiology. EgHF showed a degree of nonspecificity which did not allow direct detection of AE cases. Antibody reaction with Em2 resulted in the detection of 2 asymptomatic clinical cases of AE (seroprevalence 0.01%) within this population of blood donors. A further 4 persons were positive in Em2-ELISA. These 4 persons had negative imaging studies and will be followed serologically and clinically.

Prevention of traveler's diarrhea by the tablet form of bismuth subsalicylate

In a randomized double-blind study, Swiss adults traveling to tropical countries for 12 to 28 days took a solid formulation of bismuth subsalicylate (1.05 or 2.1 g/day on a twice-daily regimen) or placebo. Efficacy was evaluated in 231 volunteers. Diarrheal incidence was reduced by 41% in persons taking the high dose (P = 0.007) and by 35% in those taking the low dose (P = 0.03) with excellent compliance. No serious adverse reactions occurred, but objectionable taste, constipation, and nausea were seen more frequently with active medication (P = 0.04). Twenty patients provided stool samples: no bacteria were detected in the 8 volunteers who were on active medication, but various bacteria were found in 5 of the 12 patients who had taken placebo (P = 0.04).

Treatment of hydatid disease with high oral doses of mebendazole. Long-term follow-up of plasma mebendazole levels and drug interactions

Plasma mebendazole levels were analysed retrospectively in patients treated for inoperable infections with Echinococcus multilocularis or granulosus. In 10 patients receiving mebendazole at 4 dose levels there was no relation between dose and plasma concentration. In 17 patients followed on the same dose for more than 18 months, the plasma levels varied with individual coefficients of variation ranging from 27 to 72%. The data reveal the limitations of single measurements of plasma mebendazole and emphasize the need for repeated monitoring. Coadministration of phenytoin and carbamazepine seemed to lower plasma levels, presumably as a result of enzyme induction. It was not possible appreciably to raise the mebendazole concentrations by inhibition of drug metabolizing enzymes with cimetidine.

Effect of plasma mebendazole concentrations in the treatment of human echinococcosis

High oral doses of mebendazole were given for a mean period of 23 months to 22 patients with inoperable alveolar or cystic echinococcosis (Echinococcus multilocularis n = 18, E. granulosus n = 4). Clinical, morphological, biochemical and serological findings and plasma mebendazole levels were monitored. Clinical and biochemical improvement or stabilization was observed in 17 patients but the parasitic lesions did not decrease in size in most instances. One patient died shortly after onset of therapy with hemorrhage of esophageal varices. Three patients with alveolar and one with cystic echinococcosis had evidence of progressive disease such as increase of cholestasis, destruction of lumbar vertebrae and growth of an intraperitoneal cyst. The plasma mebendazole levels (4 hr after the morning dose) of the latter 4 patients were 0.09 +/- SD 0.02 mumol/l, while in those with clinical stabilization or improvement it was 0.30 +/- SD 0.14 mumol/l (P less than 0.001). These preliminary data indicate 1) a good clinical response to chemotherapy in most patients despite unchanged size of the parasitic lesions, and 2) a direct correlation of clinical response with plasma mebendazole levels.

Treatment of cystic echinococcosis (Echinococcus granulosus) with mebendazole: assessment of bound and free drug levels in cyst fluid and of parasite vitality in operative specimens

Chemotherapy of the larval stage of Echinococcus granulosus in man with high oral doses of mebendazole has only been partly successful. In order to improve effective pharmacotherapy of this disease with mebendazole, the optimal time for blood sampling has been assessed and the mebendazole concentrations acting on the parasite have been compared with their viability. The optimal time for blood sampling was analysed in 14 patients during longterm treatment with mebendazole. The plasma level 4 h after the morning dose exhibited the best correlation with the average 24-h concentration, suggesting that the plasma level should be monitored 4 h after the morning dose. In 22 patients undergoing surgery for hydatid disease, the mebendazole concentration in cyst fluid was significantly correlated with its plasma level 4 h after the morning dose. In 13 of them the free drug concentration was determined by equilibrium dialysis and it was almost identical with the free mebendazole concentration in plasma. Results of viability tests in 12 cases revealed viable cysts in 6 cases and possibly viable cysts in 6 other cases. Even patients treated for more than 12 months still had viable cysts.

Cerebral cysticercosis: treatment with praziquantel. Report of two cases

Two patients with cerebral cysticercosis are described: one with a long-standing infection with multiple intracerebral calcifications, and one who had become infected only recently. Treatment with praziquantel 50 mg/kg body weight daily for 14 days resulted in clinical and radiological improvement in the first patient, although she obviously still harbored a number of viable non-calcified parasites. The second patient was completely cured by the same praziquantel regimen. Both patients needed temporary corticosteroid treatment to suppress development of intracranial hypertension. Computerized tomographic scanning and regular measurement of serum antibody titers against cysticercal and echinococcal antigen seem appropriate methods for follow-up of the effect of chemotherapy.

Abnormal glucuronidation of zomepirac in patients with cirrhosis of the liver

The disposition of zomepirac was investigated in 18 patients with various liver diseases and in 10 healthy normal subjects in order to further test the hypothesis that glucuronidation of drugs may be spared in liver disease. Severity of the liver disease was assessed by the galactose elimination capacity. Following oral administration of zomepirac (200 mg), plasma and urinary drug concentrations were measured by high-pressure liquid chromatography. Urine was assayed before and after alkaline hydrolysis. The apparent oral clearance of zomepirac was 3.7 +/- S.D. 1.2, 3.0 +/- 0.8, and 1.8 +/- 0.6 ml . min-1 . kg-1 in normal subjects, patients with mild liver disease, and cases with cirrhosis, respectively. In patients with liver disease, the reduction in zomepirac clearance was significantly correlated with the abnormalities in galactose elimination capacity (r = 0.83, n = 18), suggesting that the functioning liver cell mass was the major determinant of the rate of zomepirac disposition. These results are not consistent with the original hypothesis but suggest that--in contrast to ether-glucuronidation--ester-glucuronidation may be abnormal in liver disease. Dosage adjustments may, therefore, be necessary in patients with cirrhosis of the liver.

Preliminary observations on the biliary elimination of mebendazole and its metabolites in patients with echinococcosis

The biliary excretion of mebendazole has been investigated in two patients to whom it was given for the treatment of echinococcosis, although it was found to be only partly effective. Oral mebendazole was extensively metabolized and the conjugated parent substance and its metabolites were excreted in the bile. One patient without cholestasis and with normal liver function had an apparent total biliary clearance (776 ml/min) which approached the hepatic plasma flow. The other patient with cholestasis and impairment of the hepatic drug metabolizing capacity showed a drastically reduced apparent total biliary clearance of 3.8 ml/min. The average plasma level of mebendazole was significantly lower in the former and higher in the latter patient (0.06 and 0.91 nmol/ml, respectively). The data suggest that impaired metabolism and/or biliary elimination can account for the higher plasma mebendazole level in patients with liver damage.

Chemotherapy of larval echinococcosis with mebendazole: microsomal liver function and cholestasis as determinants of plasma drug level

High oral doses of mebendazole have been only partly effective in the treatment of patients with alveolar or cystic echinococcosis, possibly due to an inadequate plasma concentration of the drug in some patients. In order to improve therapeutic results the influence of liver function on the plasma levels of mebendazole was investigated during long term therapy. Plasma mebendazole concentrations measured before the morning dose (trough values) showed a highly significant, negative correlation both with the aminopyrine breath test (ABT; rs = -0.78, n = 14, p less than 0.001) and the second exponential component of bromsulphthalein elimination (BSP- k2; rs = -0.74, n = 12, p less than 0.01). These relationships also applied over longer than a single day, since trough and peak mebendazole levels observed over an interval of 6 months before and after testing liver function were equally well correlated with ABT and BSP-k2. The daily dosage and other liver function tests seemed to be of minor importance in determining the plasma levels. It was concluded that the microsomal function of the liver and/or cholestasis might be important determinants of plasma mebendazole levels. The results of the study imply that higher and more effective mebendazole concentrations might be achieved by inhibition of the drug metabolizing capacity of the liver rather than by increasing the dose of mebendazole.

Treatment of human echinococcosis with mebendazole. Preliminary observations in 28 patients

Preliminary results of a long-term, prospective therapeutic trial with mebendazole in 28 patients mainly with inoperable echinococcosis are reported. The course of disease was monitored closely and plasma mebendazole levels were checked regularly. A major problem is the lack of reliable methods for defining and measuring early success or failure of therapy. Most of the patients improved clinically. No marked change of parasitic lesions was observed except in one patient with constantly low plasma mebendazole levels who deteriorated. No serious side effects occurred. The preliminary results are encouraging and suggest that mebendazole has a "parasitostatic" effect on larval growth.

Chemotherapy of alveolar echinococcosis. Comparison of plasma mebendazole concentrations in animals and man

High oral doses of mebendazole have been only partly effective in the treatment of patients with alveolar or cystic echinococcosis. In order to improve therapeutic results the pharmacology of mebendazole has been investigated. Jirds experimentally infected with larval Echinococcus multilocularis were given food containing mebendazole 100 to 1000 ppm. Drug plasma concentrations above 0.25 mumol/l were associated with a reduction in parasite weight to 1 to 10% of that in untreated controls. In treated animals parasite weight was negatively correlated with the plasma mebendazole concentration and with the duration of therapy. In patients on long term therapy with similar doses of mebendazole (16 to 48 mg/kg per day), plasma concentrations were much lower than in jirds. Only 19% of fasting plasma concentrations exceeded 0.25 mumol/l. Plasma concentrations 4 h after the morning dose did not exceed this value in 48% of cases. The results can be explained by the irregular drug absorption and short plasma half life observed in 7 hospitalized patients. It is likely that better results would be obtained if doses of mebendazole were adjusted to produce peak plasma levels exceeding 0.25 mumol/l.

[Renin-angiotensin-aldosterone system in essential hypertension. Inappropriately high plasma aldosterone in young patients with severe hypertension and in older hypertensives]

Both in male (n = 353) and in female patients (n = 211) with essential hypertension supine (basal) plasma renin activity showed an age-dependent significant decrease whereas plasma aldosterone remained almost unchanged in women or was even slightly increased with age in men. In younger hypertensives (15-34 years) a significant inverse correlation between plasma renin activity and mean arterial blood pressure could be observed. On the other hand, middle-aged men (35-50 years) showed a positive relationship between renin and blood pressure whereas in females of the same age group no correlation between these two parameters was found. In older patients (greater than 50 years) of both sexes a positive correlation between renin activity and mean arterial blood pressure was obtained. In all age-groups and in both sexes there was either no correlation, or only a weak (positive) one, between plasma aldosterone and mean arterial blood pressure. These findings suggest that in essential hypertension renin secretion is regulated mainly by blood pressure. The observed sex and age-related differences may be due to changes in the renovascular system. The inappropriately high plasma aldosterone concentrations (compared to the relatively low renin levels) in younger hypertensives with severe hypertension, and in the older population, document disturbed aldosterone secretion which probably contributes to the elevated blood pressure in these patients.

[Effect of a chronic alpha adrenergic receptor blockade on basal secretion of renin in essential hypertension]

To investigate the effect of chronic alpha-adrenergic receptor blockade on renin release, plasma renin activity (PRA) was determined overnight at short intervals in 9 patients with essential hypertension before and after 7 days medication with phenoxybenzamine (20 mg orally/day). Inhibition of basal (supine) renin secretion in response to alpha-adrenergic receptor blockade was more apparent in patients with elevated PRA (n = 3) than in those with normal PRA. On the other hand, patients with low PRA (n = 2) even showed an increase in renin release. In addition, night-day variations with secretory episodes in PRA were blunted during drug administration. It is suggested that alpha-adrenergic receptor blockade inhibits renin secretion distal to its blockade of specific adrenergic receptors. However, the increase in renin release during phenoxybenzamine observed in patients with low PRA indicates that the responsiveness of renin secretion to stimulatory effects (most probably induced by the lowered blood pressure in our patients) remained intact during alpha-adrenergic receptor blockade.

Primary aldosteronism: inability to differentiate unilateral from bilateral adrenal lesions by various routine clinical and laboratory data and by peripheral plasma aldosterone

In 31 patients with primary aldosteronism routine clinical and laboratory data, the effect of orthostasis on plasma aldosterone (PA), plasma renin activity (PRA) and cortisol (PC), effect of fludrocortisone or high sodium intake on basal PA and night-day fluctuations of basal PA and PC with and without suppression of pituitary ACTH by dexamethasone were determined to differentiate patients with a unilateral aldosterone producing tumour (adenoma, APA, n=20; carcinoma, CA, n=1) from those with idiopathic bilateral adrenal hyperplasia (IAH, n=10). Mean systolic and diastolic blood pressure, age, serum potassium and urinary excretion of sodium and potassium were not significantly different in both groups of patients. Normokalaemic primary aldosteronism occurred both in patients with APA (n=2) and in patients with IAH (n=1). Mean basal PA and mean urinary excretion rate of aldosterone-18-glucuronide were higher though not significantly different in patients with APA or CA than in those with IAH. A substantial number of the patients with APA (n=5) and with IAH (n=3) showed urinary excretion rates of aldosterone-18-glucuronide less than 13 microgram/24 h. Mean PA and PRA significantly increased (P less than 0.025) in patients with IAH in response to posture. However, these changes also occurred at times in some patients with APA. Both fludrocortisone and high sodium intake produced a variable and no group-specific effect on basal PA. Night-day variations in PA were positively correlated with those in PC in all patients with APA (n=12) and in 5 of 8 patients with IAH. A dissociation of PA and PC, however, was only observed in patients with IAH. Finally, the effect of dexamethasone on plasma aldosterone curves was variable in both groups of patients. Our results indicate that under the described conditions analysis of routine clinical and laboratory data and of peripheral PA, PRA and PC are of limited value in differentiating patients with APA or CA from those with IAH.

[Aldosterone and renin in liver cirrhosis with ascites]

Supine plasma aldosterone and plasma renin activity were determined in patients with cirrhosis of the liver and ascites (n = 10). Most of the patients initially showed an increase in plasma aldosterone and plasma renin activity. However, values within the normal range were observed (plasma aldosterone, n = 3; plasma renin activity, n = 4). In the ascitic fluid renin activity could not be detected, whereas aldosterone concentrations correlated significantly with the respective plasma levels (r = 0.8, p less than 0.01). During therapy with spironolactone alone (n =2) or in combination with furosemide (n = 4), diuresis and natriuresis showed no correlation with changes in plasma aldosterone and/or plasma renin activity. Our results suggest that other factors than renin and aldosterone secretion may be important in the formation of ascites in patients with cirrhosis of the liver. In addition, the inverse correlation between mean arterial blood pressure and plasma renin activity (r = -0.65, p less than 0.05) found in our patients supports the assumption that the increase in renin secretion is probably induced by changes in (renal) hemodynamics.

Effect of a spirolactone on plasma and urinary aldosterone in primary aldosteronism

In primary aldosteronism due to an adrenal adenoma (n=2), treatment with a spirolactone (160 mg Canrenone/day for 7 days) decreased plasma aldosterone and urinary aldosterone-18-glucuronide. However, in the presence of a normalization in urinary aldosterone 18-glucuronide plasma aldosterone remained elevated above normal. Continued therapy with higher doses (320 mg/day for 7 days and 480 mg/day for 28 days) did not significantly alter plasma aldosterone, while urinary aldosterone-18-glucuronide returned to values comparable to those obtained before therapy. Cessation of the drug resulted in a marked increase in plasma aldosterone and urinary aldosterone-18-glucuronide. The results indicate that in primary aldosteronism due to an adrenal adenoma, the spirolactone (Canrenone) inhibits aldosterone biosynthesis and seems to influence aldosterone degradation.

[Plasma renin activity and plasma aldosterone in essential hypertension: effect of age and diastolic blood pressure]

In patients with essential hypertension a gradual decrease in basal and stimulated renin secretion was found with increasing age. Stimulated plasma aldosterone decreased similarly; however, the observed changes were less pronounced. Young patients (less than 35 years) with high renin hypertension had lower diastolic blood pressure than patients with low renin hypertension in the same age group. Contrary to these findings, a markedly higher diastolic blood pressure was observed in patients over 35 years of age with high renin hypertension than in the group of patients with low renin hypertension. These results indicate that neither high nor low renin essential hypertension patients represent homogeneous groups. Furthermore, the dissociation between changes in renin activity and plasma aldosterone points to a disturbed relationship between the renin angiotensin system and aldosterone secretion in essential hypertension.

[Primary aldosteronism]

The syndrome of primary aldosteronism is caused either by an aldosterone-producing adenoma or by idiopathic bilateral adrenal hyperplasia. Hypokalemic hypertension is the leading symptome of the disease. Diagnosis is by the combination of abnormally high and non-suppressible aldosterone values with undetectable or low renin values unresponsive to postural changes or salt restriction. Patients with aldosterone-producing adenoma normally show a fall in plasma aldosterone in response to posture and ACTH-dependent circadian rhythm of aldosterone, whereas bilateral hyperplasia is characterized by postural increases in plasma aldosterone and an ACTH-independent diurnal aldosterone rhythm. These creteria serve to differentiate between adenoma and hyperplasia. An aldosterone-producing adenoma can be localized by veinography, determination of aldosterone concentration in both adrenal veins and by 131I-cholesterol scintigraphy. In our hands the determination of aldosterone in blood from both adrenal veins is the most efficient procedure. In interpreting the results, however, rhythmic and sudden changes in adrenal hormone secretion should be considered. In cases where no adrenal venous blood is obtained, 131I-cholesterol scintigraphy may be used to localize adenoma. In patients with aldosterone-producing adenomas unilateral adrenalectomy should be performed, whereas patients with idiopathic bilateral hyperplasia should receive antihypertensive therapy. As rare instances of primary aldosteronism, a case of aldosterone-producing carcinoma of the adrenal cortex and a case of presumably unilateral adrenal hyperplasia are reported.

[Primary aldosteronism: diagnosis, laterality and regulation of hormone secretion]

In 16 patients with hypokalemic hypertension the combination of abnormally high and unsuppressible plasma aldosterone with low or undetectable renin activity led to the diagnosis of primary aldosteronism. To differentiate between aldosterone producing adenoma and idiopathic bilateral hyperplasia, determination of aldosterone concentration in both adrenal veins was performed in 12 patients. In 4 of these patients the two forms of primary aldosteronism could not be differentiated as in these cases only one of the two adrenal veins simultaneously showing an abnormally high aldosterone concentration could be canulated. Plasma aldosterone and plasma cortisol were determined overnight (20.00-8.00 h) at short time intervals in 8 patients with adenoma, 1 patient with carcinoma of the adrenal cortex and 3 patients with bilateral hyperplasis. In all patients with adenoma a significant correlation between aldosterone and cortisol was observed (p less than 0.05-0.001) whereas no correlation was seen in the patients with hyperplasia and carcinoma. The clinical importance of these findings is that in the presence of ACTH-dependent secretion of aldosterone the site of the adenoma can be predicted even when blood from only one adrenal vein is obtained.