Endocrine Abstracts

Background

Primary aldosteronism (PA) affects 5-20% of all patients with hypertension, and is likely the most common treatable cause of hypertension. Patients with PA have higher risk of cardiovascular disease, atrial fibrillation and stroke. We aimed to estimate the prevalence of PA in patients with recent stroke.

Methods

We prospectively recruited 300 patients who were admitted to the acute stroke unit of a single tertiary centre with the diagnosis of cerebrovascular accident (both ischemic and haemorrhagic) or transient ischemic attack. At 2-4 months post-stroke, all patients had screening blood tests for serum aldosterone (ng/dl) and plasma renin activity (ng/ml/hr) Patients with aldosterone-renin-ratio (ARR) >10 underwent confirmatory seated salt loading test (SLT). This study was registered with Clinicaltrials.gov (NCT03789357).

Results

300 patients were recruited, of which 192 underwent ARR screening. Mean age of the 192 patients was 56.7 ± 10.6 years, 55 (28.6%) were females, and 130 (67.7%) had hypertension. 156 (81.3%) had ischemic stroke, 20 (10.4%) had haemorrhagic stroke and 16 (8.3%) had transient ischemic attack. 26 of 192 (13.5%) patients had positive ARR. Patients with positive ARR were more likely to have AF, 4 of 26 (15.4%), compared to those with negative ARR, 5 of 166 (3.0%), P =0.021, and they also had higher baseline diastolic blood pressure. 4 of 12 (25%) patients who underwent confirmatory SLT had post-saline aldosterone >5ng/dl. One patient had baseline aldosterone >20 ng/dl with suppressed renin and spontaneous hypokalaemia, which was consistent with diagnosis of PA. In total, 5 patients were diagnosed with PA, giving a prevalence of 2.6% in all stroke patients, and 3.9% amongst those with hypertension. Prevalence rates were higher in certain subgroups of patients: 16.7% (2 of 12) in those with hypertension and hypokalemia, 22.2% (2 of 9) in hypertension and AF, and 6.1% (3 of 49) in young stroke patients aged ≤50 years. If screening for PA was only done in patients with hypokalemia or age ≤50 years, half of the cases would have been missed.

Conclusion

In addition to current guideline recommendations to screen for PA in certain subgroups of hypertensive patients, e.g. resistant hypertension, hypertension with hypokalemia, it will be worthwhile to screen hypertensive patients with previous stroke, who are at high risk of cardiovascular events. In post-stroke patients who have good functional recovery, accurate diagnosis and treatment of PA can improve and potentially cure hypertension, and prevent a subsequent stroke which could be catastrophic.