Endocrine Abstracts (2008) 16 P37

The German Conn's registry: comorbidities in over 700 patients with primary hyperaldosteronism

Eric Born-Frontsberg1, Caroline Schirpenbach2, Stefanie Hahner3, Felix Beuschlein2, Martin Bidlingmaier2, Sven Diederich4, R Lorenz5, Lars Rump6, Jochen Seufert7, Stefan Endres2, Marcus Quinkler1 & Martin Reincke2

1Klinische Endokrinologie, Charité Campus Mitte, Charite Universitätsmedizin Berlin, Berlin, Germany; 2Medizinische Klinik Innenstadt, Ludwig-Maximilians-Universität München, München, Germany; 3Medizinische Klinik und Poliklinik I, Julius-Maximilians-Universität, Würzburg, Germany; 4Endokrinologikum Berlin, Berlin, Germany; 5Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, Ludwig-Maximilians-Universität München, München, Germany; 6Marienhospital, Ruhr-Universität Bochum, Herne, Germany; 7Medizinische Klinik II, Albert-Ludwigs-Universität, Freiburg, Germany.

Objective: Hypokalemic Conn’s syndrome is a rare disease with a prevalence of 0.5% in unselected hypertensive populations. However, recent studies indicate a higher prevalence of a milder variant of Conn’s syndrome, reaching 10% in some studies. Long term outcome and health care costs of hypo- and normokalemic variants are largely unknown. The National Conn’s Registry is an initiative to create a national database of sufficient epidemiological strength to investigate co-morbidity and mortality in these patients.

Methods: The registry has at present 7 participating centres in 5 locations and uses an electronic database to assure comparison of different centres. Since 07/2006 retrospective data were included in the database from patients with Conn’s syndrome diagnosed between 1990 and 2007.

Results: Evaluation of the retrospective data entry provide the following results: Of the 726 patients (60.4±13.7 years, range 6–96 years), 54.3% had the hypokalemic variant of the disease. The mean RR was 158±29 mmHg systolic and 94±16 mmHg diastolic. Morbidity of cerebrovascular events (TIA, PRIND, stroke) in the overall cohort was high with 9.6% of patients. The prevalence of cardiovascular morbidity (angina pectoris, myocardial infarction, coronary angioplasty) was 13.5% in our cohort. Atrial fibrillation occurred in 8.4% of the patients and other atrial or ventricular dysrhythmia in 5.5% of the patients. Chronic renal failure was present in 10.9% of patients, and sleep apnea in 8.1% of patients. Overall co-morbidities were more frequent in hypokalemic than in normokalemic individuals.

Conclusion: Our data show high proportion co-morbidites for Conn’s syndrome, which is endorsed by previous results from France describing a 3–4 fold higher prevalence of stroke, myocardial infarction and atrial fibrillation in a small cohort of primary aldosteronism (n=124) compared to patients with essential hypertension (n=465). In addition, our data demonstrate evidence that the hypokalemic variant of Conn’s syndrome has a higher morbidity than the normokalemic variant.