Endocrine hypertension refers to high blood pressure (hypertension) caused by the abnormal production of hormones.
The most common form of endocrine hypertension is primary aldosteronism (PA), also known as Conn syndrome. In primary aldosteronism, the adrenal glands, which sit on top of each kidney, produce too much aldosterone (a hormone that retains salt in the body). This can lead to excess salt and fluid retention and increased blood pressure. It also increases the risk of heart arrhythmia, heart attack and stroke more than ordinary forms of hypertension.
Primary aldosteronism affects five to 10 per cent of those with hypertension but often goes undiagnosed. It is treatable with medication and/or surgery, depending on the cause.
High blood pressure dramatically increases the risk of heart attack and stroke.
Our primary aldosteronism research
Caused by a hormone imbalance, primary aldosteronism is often undiagnosed or given incorrect treatment. Hudson Institute research teams are working to improve the diagnosis and treatment of this serious but potentially curable disease and related conditions.
Dr Jun Yang explains more about her research on high blood pressure and primary aldosteronism with Dr Norman Swan on the ABC Health Report.
High blood pressure and primary aldosteronism explained
Dr Jun Yang discusses her research in primary aldosteronism, a common, potentially curable but often neglected form of high blood pressure. Dr Jun Yang raises awareness about primary aldosteronism and how a single blood test could change the course of peoples lives, and even lead to a cure.
Seeking non-invasive ways to detect hormone-induced high blood pressure
Diagnosis. High blood pressure may be caused by an overactive adrenal gland that produces too much aldosterone – a hormone which controls salt balance. If only one adrenal gland is involved, treatment can involve the surgical removal of this gland. Investigation on whether one or both adrenal glands are affected currently requires an invasive blood test. Dr Jimmy Shen and Hudson Institute’s team together with Dr Ian Jong, Monash Health are exploring whether non-invasive scans can be used as an alternative to the invasive blood test.
Hunting a potentially curable cause of high blood pressure
Detection. Primary aldosteronism (PA) can cause preventable strokes, heart attacks, heart arrhythmias and kidney failure. PA manifests as high blood pressure and is potentially curable but doctors do not routinely screen for the condition, which can be a silent killer. Dr Renata Libianto’s goal is to increase the detection of PA through a simple blood test, so patients can be effectively treated and live healthier lives.
Improving the diagnosis of hormone-related high blood pressure
Molecular studies. Detection. Health professionals measure hormone levels to diagnose primary aldosteronism, which involves excess production of the hormone aldosterone and can lead to high blood pressure. However, current methods used are not always accurate. Dr Renata Libianto is investigating cell-based markers of aldosterone activity that reveal if the excess production of aldosterone is wreaking havoc in the body.
Advocating for the timely diagnosis of primary aldosteronism
Advocacy. Dr Jun Yang, Mr David Wyatt (a consumer advocate based in Melbourne) and the research team are working with the US-based consumer group, Primary Aldosteronism Foundation, to help patients worldwide to advocate for changes in how the condition is diagnosed and managed. The team are collating data on patients’ experiences and actively inviting consumers to inform our research priorities so that the research is relevant to the patients’ needs.
The main outward sign of primary aldosteronism is high blood pressure. However, the condition may appear like ordinary hypertension (or essential hypertension – high blood pressure that does not have a known secondary cause). As a result, many people who have primary aldosteronism are unaware of the root cause of their high blood pressure or take unsuitable medications which are not directed at treating the aldosterone excess. They also face an increased risk of cardiovascular problems, including stroke, heart attacks and heart failure, compared to those who have similar blood pressure levels not caused by excessive aldosterone.
Causes of primary aldosteronism
Primary aldosteronism is caused by the increased production of aldosterone from the adrenal gland(s). The excessive aldosterone may be produced by a tumour or tumours on the adrenal gland or enlarged adrenal gland or glands. In some cases, the condition can run in the family if caused by a genetic mutation that affects multiple family members.
Diagnosis of primary aldosteronism
Primary aldosteronism is diagnosed by blood and urine tests, and/or a CT scan of the adrenal glands. In some cases adrenal vein sampling, which measures and compares hormones produced by each adrenal gland, is needed.
Primary aldosteronism causes more injury to the heart and blood vessels than high blood pressure alone, so early diagnosis is important. Only one in 200 people with primary aldosteronism are diagnosed because many doctors do not screen for it.
The Endocrine Hypertension Service at our precinct, including Hudson Institute and Monash Health, offers Victoria’s only streamlined service for the diagnosis of primary aldosteronism, in addition to an outreach program supporting general practitioners to facilitate increased primary aldosteronism testing in the community.
Treatment of primary aldosteronism
Hypertension related to a hormone imbalance is usually treatable and possibly curable with surgery if it involves a tumour or tumours. In the case of primary aldosteronism, there are medications which specifically block the actions of aldosterone and therefore offer highly effective treatment. Patients may need fewer medications compared to before the diagnosis because s/he is able to receive targeted treatment of the root cause of the hypertension rather than non-specific medications. If the aldosterone is produced by an adrenal tumour, then the condition may be cured by surgical removal of the affected adrenal gland.
Long term effects of primary aldosteronism
If undiagnosed, primary aldosteronism can lead to higher blood pressure that becomes increasingly difficult to control with medication. This can leave those who have it at risk of strokes, heart attacks at a younger age and in some cases heart and kidney failure. Others may end up taking numerous ineffective blood pressure medications while still suffering from high blood pressure. If correctly diagnosed, they have a good chance of controlling the condition with appropriate medication or surgery.