The cardiovascular system is made up of the heart, blood vessels and blood. By studying the interactions between hormones and the cardiovascular system, endocrinologists can contribute significantly to a better understanding of cardiovascular disease and the management of disorders related to it.
Hypertension or high blood pressure is not unusual – and it is also the most common modifiable condition that increases our risk of cardiovascular disease, which can result in angina, heart attacks, heart failure, stroke, dementia, kidney disease and failure, peripheral vascular disease and erectile dysfunction. It can form part of a complex of metabolic abnormalities alongside polycystic ovarian syndrome, affecting fertility and sometimes causing problems in pregnancy. Most people have hypertension because of the interplay between their genes and lifestyle, and we can help you make the necessary lifestyle adjustments to mitigate this. For others – around 15% of patients – the hypertension is secondary and there is a specific reason for it. We will consider if this is likely and, if needs be, investigate. The treatment always depends on the cause, but the important thing is always to reduce the risk of cardiovascular harm right across your body.
When treating hypertension, the goal is always to help reduce the harm and damage it causes. There are numerous ways to do this – including looking at how your lifestyle might be improved – and there are several classes of medication available. Depending on the cause of your hypertension, your priorities, lifestyle and other conditions, we can help lower the blood pressure safely and quickly. If there are complications, we can work – with other colleagues if necessary – to diagnose and treat these. Some patients need several different types of medication, each bringing its own benefits, side effects and limitations. What works for one person won’t necessarily work for the next, and our role is always to find the combination that will work for you. This may involve attending to other conditions that affect your cardiovascular risk, such as diabetes or pre-diabetes, lipid and cholesterol disorders, obesity or overweight, sleep apnoea, kidney damage and liver disease, in particular metabolism-associated steatotic liver disease (MASLD), previously known as non-alcoholic steatotic or fatty liver disease (NASH/NAFLD).
Conn’s syndrome occurs when the adrenal glands produce excess aldosterone, resulting in high blood pressure. We can work with you to diagnose and manage this condition, whether it’s due to unilateral adrenal adenoma or bilateral adrenal hyperplasia. We sometimes work with other professional colleagues to sample the adrenal veins for aldosterone, and work with an endocrine surgeon if a unilateral adenoma is responsible. If you have excess aldosterone caused by bilateral adrenal hyperplasia, we can block that hormone to help control your blood pressure using spironolactone or eplerenone.
Only about 1% of patients with Conn’s syndrome have their condition diagnosed. Aldosterone, the causative hormone in Conn’s, causes problems for the heart and blood vessels above and beyond those caused by high blood pressure, so it cannot be overstated how important it is to explore the cause of your hypertension with an expert or an endocrinologist with a specific interest in this area. As endocrinologists with a specialist hypertension clinic this is an important area of our clinical practice.
The current tests to identify Conn’s have to be performed systematically, often withdrawing medication so it doesn’t interfere with the hormonal tests, and then establishing the patient safely on new medication. If this is the correct line of investigation, we will manage this careful balance with you.
Phaeochromocytoma and paraganglioma are rare tumours of the autonomic nervous system, which controls the hormones and neurotransmitters adrenaline, noradrenaline and dopamine. These hormones are essential to our health and help the body respond to changes in environment, posture, temperature and food. Tumours in this part of the nervous system can cause severe hypertension, palpitations and sweats. They are usually benign but can be cancerous, and they can run in families. We routinely work with patients to first identify their phaeochromocytoma or paraganglioma using laboratory and diagnostic imaging, and then help them manage their condition in collaboration with expert colleagues. We also consider how the diagnosis might be relevant to other family members.
As we age, our arteries narrow, and this affects the blood supply to the heart, brain and kidneys, as well as that to the lower limbs and erectile function. When the arteries are narrowed – or stenosed – the kidneys can compensate by making hormones to try to increase the blood pressure to in turn increase the blood supply. This makes hypertension in the rest of the body worse. Renal artery stenosis is a particular consideration when there is severe hypertension because it is resistant to many drugs. We consider whether this is likely, and if so, what can be done about it.
Hypertension in young women can be severe and difficult to treat because it may be the result of overgrowth of the connective tissue within the renal arteries and elsewhere in the body. Detailed assessment of the renal blood flow is needed for this diagnosis, using Doppler ultrasound, CT or MR angiography. If a young woman does have stenosis of the renal arteries, we will work with her to consider renal artery angioplasty as well as assess the blood vessels across the body.
In older patients, treatment can be a complex matter, considering the relative benefits and harms of angioplasty alongside other options. In each case, we look after these conditions with a small team of colleagues to ensure you get the best assessment, advice and treatment.
Lipids and cholesterol travel through the bloodstream attached to proteins. If they are present in high levels, they can have a negative effect on your health. we can advise on what kind of therapy you can take to reduce the risk, when and how you should take it, and assess what the overall risk might be.
Cholesterol is carried through the bloodstream by two types of lipoproteins: low-density lipoprotein (LDL) which can build up on the walls of arteries, and high-density lipoprotein (HDL) which helps remove LDL from the bloodstream. LDL cholesterol is often referred to as ‘bad’ and HDL as ‘good’ cholesterol. When the total amount of cholesterol in the blood (TC) is measured, patients are often given a TC:HDL ratio, which should be as low as possible, although cholesterol ratios should always be considered alongside other factors.
Our lipids give us a clue about what is happening in our heart and blood vessels, liver and kidneys, showing the concentration of particles moving back and forth between the sites in the body where they are used and processed. They are important to our cardiovascular health because if they occur at very high levels – hyperlipidaemia – they are sometimes taken up in the vessel wall, causing a narrowing of the arteries in the heart, brain, penis and peripheral vessels. This condition is known as atherosclerosis.
Not everyone’s lipids will cause them problems, but we manage lipids and cardiovascular disease for a wide range of patients and can help you understand the outcomes of any tests, when to test further, when to leave alone and when we might want to offer treatment. The most common lipid abnormalities are associated with being overweight and obese, and with pure hypercholesterolaemia. These conditions can look similar – and we sometimes use similar medications for them – but there are important differences.
High cholesterol is the most common type of hypercholesterolaemia, a condition where there are high levels of fat (lipids) in the blood. Our cholesterol is controlled by our lifestyle, but also our genetic makeup. In some patients with polygenic hypercholesterolaemia, their high cholesterol levels are caused by genetic problems that cholesterol isn’t broken down or taken out of the blood, leaving it to collect in the arteries.
Statins are the backbone treatment if we want to reduce cholesterol and cardiovascular risk, but they are not for everyone. We can help you understand why they might be necessary, when they might not be the correct treatment, and what to do if you have side effects. We can also consider alternatives or consult with specialist dietician colleagues.
Single genes causing elevated cholesterol from birth are common, and are known as familial hypercholesterolaemia (FH). In FH the risk of cardiovascular disease is much higher, and sadly most patients are not diagnosed correctly, meaning they do not receive the right treatment. We have experience in helping you decide whether you need testing for FH, arranging for the tests to be made, and then guiding your treatment. We often support your care with specialist lipid clinics where you can access the latest treatments, including alirocumab, evolocumab, or the tablet bempedoic acid.
In mixed dyslipidaemia, particularly with diabetes or obesity, the high level of lipids is often less dramatic than in pure hypercholesterolaemia but the treatment can be more complex and the risk of cardiovascular disease higher. The need to consider weight, glucose and blood pressure makes finding the right treatment all the more important. Often small adjustments over several lines of treatment are necessary, and in these cases it’s beneficial to see a doctor experienced right across metabolic medicine who can take a broad perspective, rather than consult with separate ones.
Triglycerides are a combination of three fatty acids that are absorbed from food and carried in the bloodstream as a source of energy.
Lower elevations of triglycerides usually tell us similar information about the metabolic environment in the liver and blood vessels to those patients with benign cholesterol levels, but coupled with a low HDL level (particularly when the TH:HDL ratio is high), a high level of ApoB (a protein found in ‘good’ LDL cholesterol) can suggest a greater cardiovascular risk. In such cases, we would look closely at your weight, blood pressure and glucose balance to minimise this risk.
Higher elevations of triglycerides, particularly in the high teens to 30s, are dangerous right away. There is a risk of pancreatic inflammation (pancreatitis) which can make us extremely unwell, so hypertriglyceridaemia needs prompt diagnosis and assessment in these cases, often requiring admission and specific therapy. We are experienced in identifying this condition and making the triglycerides safe again, while looking at how to prevent them from becoming high again in the context of your wider metabolic health.
Lipoprotein (a) or Lp (a) is a type of protein that carries cholesterol in the blood. It is mostly inherited, so only needs to be considered once in your life but is much less modifiable than cholesterol, HDL, LDL and triglycerides. With standard measures of cardiovascular risk, it is often not taken into consideration. We can help decide whether we should measure it, integrate this information for you and see how it changes your health – and then offer relevant advice, treatment or investigations. Therapies to lower it to improve cardiovascular health are in development, but until they are proven to work safely they are only relevant to patients in clinical trials.
Our work includes the diagnosis and treatment of iron, B12 and folate deficiency. We are particularly interested in using safer alternatives to red blood cell transfusion, reducing the side effects of iron therapy and ensuring anaemia is corrected before surgery and before, during and after pregnancy. We are also concerned with the diagnosis and management of pernicious anaemia and dietary B12 deficiency.
Dr Kelly chairs the London Regional Transfusion Committee and works closely with colleagues in haematology, gastroenterology and surgery – both nationally and at King’s College London – to ensure patients receive the right treatment to keep them feeling well now and in the future.
Iron deficiency is very common in women of childbearing age who are having regular periods, especially if they are heavy. We work hard to prevent anaemia by identifying the causes of iron loss, or the failure to absorb it early, by spotting deficiencies when it is mild, and sensibly replacing the iron. This often involves intermittent treatment across years or even decades for some patients. We work closely with gynaecology colleagues if we need specific help with menstrual blood loss.
If you need your iron stores improved for pregnancy, breastfeeding, hair and skin health, or just to improve your energy levels, we can help. Iron deficiency not only occurs in younger women; it can occur from childhood to old age. If there’s a possibility that you need iron replacement or a blood transfusion, we will work with you to find the right treatment.
Iron deficiency without good reason can be an indication of more serious problems including coeliac disease, chronic inflammation, diverticular disease, gastric inflammation and ulcers, and can even be an early indication of cancer as we get older. We can help investigate if it is appropriate or direct you to the services and colleagues who specialise in looking for cancer. This often includes gastroenterologists using endoscopy, or radiologists using CT.
Safe intravenous iron preparations have revolutionised the health and care of many patients, protecting them from fatigue, poor hair and skin health, transfusions of red cells and even surgery at times. Not all intravenous iron is the same, but we can help you find the right treatment, balancing convenience, health and short- and long-term safety, and if an iron infusion is required we have a team who can help with this.
Medications often have side effects which can be relevant to your therapy. They may be a feature of the drug itself – such as constipation with oral iron or a dry cough with ACE inhibitors – or they may be related to the excipients used to deliver the drug, for example lactose. Some side effects are common and expected because of the mechanism of the drug. Postural dizziness may occur with some blood pressure tablets; tachycardia, bradycardia, cold hands, erectile problems or gum irritation with others. Other side effects, such as muscle aches with cholesterol tablets, are not as common as the press would have us think.
We always consider how each medication works for you, how it might work with other medicines, what it’s for, and the relative benefits of adjusting the dose, reducing the amount and complexity of tablets, or substituting a new medication. This only comes through an extensive knowledge of how medications work both in isolation and together, and by taking enough time to really understand you and your treatment.