Diabetes and Heart Health: Understanding Cardiovascular Risk

Introduction: Beyond Just Blood Sugar

When someone is diagnosed with diabetes, much of the initial attention naturally focuses on blood glucose monitoring, diet, physical activity and medication. These remain important aspects of diabetes management, but cardiovascular health is another essential consideration.

Diabetes is associated with an increased risk of heart and blood vessel conditions. Over time, elevated blood glucose can contribute to vascular damage, while associated conditions such as hypertension, abnormal cholesterol levels and chronic kidney disease may further increase cardiovascular risk.

People living with diabetes have a higher risk of developing heart disease and stroke than people without diabetes. The level of risk, however, differs from person to person and is influenced by multiple clinical and lifestyle factors.

Understanding these connections can help people make informed decisions about preventive care. Appropriate diabetes management involves more than monitoring blood glucose: it also includes regular assessment of cardiovascular risk factors and treatment tailored to an individual’s needs.

Table of Contents

• The Mechanisms of Blood Vessel Damage
• Common Cardiovascular Risk Factors in Diabetes
• Understanding Diabetic Cardiomyopathy
• Heart Attacks and Less-Obvious Symptoms
• Cardiovascular Assessment and Testing in Diabetes
• Medical Management Strategies
• Lifestyle Measures to Support Heart Health
• Frequently Asked Questions

The Mechanisms of Blood Vessel Damage

To understand the relationship between diabetes and cardiovascular disease, it helps to consider how prolonged elevations in blood glucose can affect the circulatory system.

Blood vessels have an inner lining called the endothelium. This lining helps regulate blood flow, blood vessel function and interactions between blood cells and the vessel wall. Diabetes can contribute to changes in endothelial function and promote processes involved in atherosclerosis, the buildup of plaque inside arteries.

The Effects of Elevated Blood Glucose

When blood glucose remains elevated over time, it can contribute to oxidative stress, inflammation and changes in the normal functioning of blood vessels. These processes may affect the vessel lining and contribute to the development or progression of atherosclerosis.

Plaque can gradually accumulate inside arteries, including the coronary arteries that supply blood to the heart muscle. If a coronary artery becomes significantly narrowed or a plaque ruptures and a blood clot forms, blood flow to part of the heart muscle may be reduced or blocked.

This can lead to conditions such as angina or a heart attack. However, the progression of vascular disease varies between individuals and depends on several interacting risk factors.

Advanced Glycation End Products (AGEs)

Advanced glycation end products, commonly called AGEs, are compounds that form when sugars react with proteins or fats. Their accumulation can contribute to oxidative stress, inflammation and changes in the structure and function of tissues.

In diabetes, increased formation or accumulation of AGEs may contribute to vascular changes and reduced elasticity of blood vessels. These processes can interact with other factors, including hypertension, abnormal cholesterol levels and kidney disease.

AGEs are one part of the broader relationship between diabetes and vascular complications. They are not the sole cause of cardiovascular disease, and their effects should be understood within the wider context of blood glucose management and overall cardiovascular risk.

Common Cardiovascular Risk Factors in Diabetes

Diabetes often occurs alongside other conditions that influence cardiovascular health. These factors can act together to increase a person’s overall risk, although not everyone with diabetes develops all of them.

High Blood Pressure

High blood pressure, or hypertension, is an important risk factor for heart disease and stroke. Diabetes and hypertension frequently coexist, and having both conditions can increase cardiovascular and kidney-related risks.

Over time, elevated blood pressure places additional strain on the cardiovascular system and can contribute to damage involving the heart, blood vessels and kidneys.

Blood pressure management should be individualised. A healthcare professional can recommend appropriate lifestyle measures, monitoring and medication based on a person’s blood pressure readings, other health conditions and overall cardiovascular risk.

Diabetic Dyslipidaemia

Dyslipidaemia refers to abnormal levels of cholesterol or other fats in the blood. Some people with diabetes, particularly those with insulin resistance, develop a pattern that includes elevated triglycerides, lower levels of HDL cholesterol and changes in LDL cholesterol particles.

These lipid abnormalities can contribute to atherosclerosis and increase cardiovascular risk. However, cholesterol patterns differ between individuals, so laboratory testing is important when assessing an individual’s lipid profile.

Managing cholesterol may involve dietary changes, physical activity, treatment of associated conditions and medication when appropriate. Statin therapy and other lipid-lowering treatments should be considered according to the person’s age, lipid levels, established cardiovascular disease, other risk factors and applicable clinical recommendations.

Diabetes, high blood pressure and abnormal cholesterol levels can occur together, making an overall assessment of cardiovascular risk an important part of routine diabetes care.

Understanding Diabetic Cardiomyopathy

Diabetes is associated with an increased risk of heart failure and changes in heart structure and function. Researchers use the term diabetic cardiomyopathy to describe cardiac abnormalities associated with diabetes that are not fully explained by other conditions, such as coronary artery disease or hypertension.

In clinical practice, heart dysfunction can have several contributing causes, and a diagnosis requires appropriate assessment rather than an assumption based on diabetes alone.

Diastolic Dysfunction: When the Heart Has Difficulty Relaxing

Diastolic dysfunction occurs when the heart’s main pumping chambers do not relax or fill as normally as expected between beats. It can develop in association with several conditions, including hypertension, diabetes and other forms of heart disease.

Some people may have diastolic dysfunction without noticeable symptoms. Others may experience breathlessness, particularly during physical activity, when filling pressures become elevated or when heart failure develops.

Diastolic dysfunction cannot be diagnosed from fatigue or breathlessness alone. A clinician may consider an echocardiogram and other investigations when symptoms, examination findings or the person’s medical history suggest that cardiac assessment is needed.

Systolic Dysfunction: When the Heart’s Pumping Function Is Reduced

Systolic dysfunction refers to reduced contraction or pumping function of the heart. It can occur for several reasons, including coronary artery disease, previous heart attacks and certain forms of cardiomyopathy.

People with diabetes have an increased risk of developing heart failure, but the condition does not progress in the same way in everyone. Some people develop problems with relaxation and filling, while others develop reduced pumping function or a combination of abnormalities.

Symptoms of heart failure can include breathlessness, unusual fatigue, swelling of the legs or ankles and difficulty breathing when lying down. These symptoms can also have other causes and should be evaluated in the appropriate clinical context.

Early identification of relevant risk factors and suitable management can help address cardiovascular health before or after symptoms develop.

Heart Attacks and Less-Obvious Symptoms

A heart attack occurs when blood flow to part of the heart muscle is substantially reduced or blocked, resulting in injury to the heart muscle. Chest discomfort is a common symptom, but not everyone experiences the same warning signs.

People with diabetes may also have nerve damage, known as diabetic neuropathy. In some cases, damage affecting sensory nerves may contribute to reduced awareness of typical symptoms. Heart attacks can therefore occur with mild, unusual or unrecognised symptoms in some people with diabetes.

Why Symptoms May Not Be Typical

Not all heart attacks begin with severe chest pain. Some people experience discomfort or other symptoms that may initially be mistaken for indigestion, fatigue, stress or another condition.

The absence of classic chest pain does not rule out a heart attack. At the same time, symptoms such as tiredness or indigestion alone do not establish that a heart attack is occurring.

Possible heart attack symptoms include:

• Chest discomfort, pressure or tightness.
• Shortness of breath.
• Unusual fatigue or weakness.
• Nausea or discomfort resembling indigestion.
• Sweating, lightheadedness or dizziness.
• Discomfort spreading to the arm, shoulder, back, neck or jaw.

Symptoms can vary between individuals. People with diabetes should understand that cardiovascular problems may sometimes present differently from the symptoms they expect.

If you suspect a heart attack, seek emergency medical care immediately. Do not wait for severe chest pain to develop or assume that symptoms are harmless because they are mild.

Cardiovascular Assessment and Testing in Diabetes

Assessing cardiovascular risk is an important part of diabetes care. The appropriate assessment depends on the person’s medical history, symptoms, examination findings and existing risk factors.

Routine diabetes follow-up commonly includes attention to blood glucose management, blood pressure, cholesterol, smoking status, kidney health and other factors relevant to cardiovascular risk.

However, diabetes alone does not mean every person needs an immediate cardiology consultation, an echocardiogram, a treadmill stress test or coronary calcium scoring. Current diabetes guidance does not recommend routine screening for coronary artery disease in every asymptomatic person when cardiovascular risk factors are being appropriately managed.

Further investigations may be appropriate when symptoms, examination findings or particular risk factors indicate a need.

The Echocardiogram

An echocardiogram is an ultrasound examination that provides information about the heart’s structure and function. It can assess features such as chamber size, pumping function, valve function and certain measures related to how the heart relaxes and fills.

A clinician may recommend echocardiography when there are symptoms or findings suggesting heart failure, structural heart disease or another condition that requires assessment.

It is not necessary for every person with diabetes solely because they have the condition. The decision should be based on the clinical situation and the purpose of the test.

The Treadmill Stress Test

A treadmill stress test evaluates how the heart responds to exercise. Depending on the test used, it may monitor the heart’s electrical activity, heart rate, blood pressure and symptoms during physical exertion.

Stress testing may be considered for selected people when symptoms or other clinical findings raise concern about coronary artery disease or another cardiovascular problem.

The test does not identify every coronary blockage, and its results must be interpreted alongside the person’s medical history and other findings. It is not routinely required for every asymptomatic person with diabetes.

Coronary Calcium Scoring

Coronary artery calcium scoring uses a specialised CT scan to detect and measure calcified plaque in the coronary arteries. The result can provide additional information about coronary atherosclerosis and may help with cardiovascular risk assessment in selected individuals.

The test does not directly show every type of plaque or establish whether a particular artery is significantly obstructed. Nor does it provide an exact prediction of whether or when a person will experience a heart attack.

Coronary calcium scoring is not automatically necessary for everyone with diabetes. A healthcare professional can help determine whether the information would be useful in an individual’s circumstances, taking into account existing risk factors, previous results and how the findings might influence management.

Medical Management Strategies

Managing cardiovascular risk in diabetes involves an individualised approach that may include blood glucose management, blood pressure treatment, cholesterol management, lifestyle changes and medication when appropriate.

The aim is to reduce relevant risk factors and manage existing health conditions. No single medicine or strategy is suitable for every person with diabetes.

Diabetes Medications with Cardiovascular Benefits

Some medications used to manage type 2 diabetes have also demonstrated cardiovascular or kidney benefits in particular patient groups.

These include certain sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs). Depending on the specific medication and the patient’s condition, these treatments may reduce selected cardiovascular or heart failure outcomes.

Their suitability depends on factors such as whether the person has established cardiovascular disease, heart failure, chronic kidney disease or other relevant risk factors. The potential benefits, risks, contraindications and cost should be considered as part of an individual treatment plan.

These medicines are not automatically appropriate for every person with diabetes, and they should be prescribed and monitored by a qualified healthcare professional.

Cholesterol Management

Managing cholesterol is an important part of cardiovascular risk reduction for many people with diabetes. Statins are commonly recommended for eligible adults according to their age, cholesterol levels, existing cardiovascular disease and overall risk.

For some individuals, additional lipid-lowering medication may be appropriate if cholesterol levels remain above the recommended range or cardiovascular risk remains high despite initial treatment.

Treatment decisions should be based on individual assessment rather than a blanket assumption that every person with diabetes needs the same medication or dose.

Blood Pressure Management

Managing high blood pressure can help reduce cardiovascular and kidney-related risks in people with diabetes.

Treatment may involve lifestyle measures and prescribed medication. ACE inhibitors or angiotensin receptor blockers (ARBs) may be suitable for particular patients, including some with hypertension, chronic kidney disease or albuminuria. The appropriate choice depends on individual clinical circumstances.

Blood pressure targets and treatment plans should be tailored to the person’s health status and tolerance of treatment.

People should not begin, stop or change prescribed cardiovascular or diabetes medications without discussing their care with a healthcare professional.

Lifestyle Measures to Support Heart Health

Lifestyle measures are an important part of diabetes management and cardiovascular risk reduction. Their effectiveness depends on individual circumstances, and they should complement rather than automatically replace prescribed treatment.

A heart-healthy eating pattern can include vegetables, fruits, whole grains, pulses and legumes, nuts, suitable sources of protein and unsaturated fats. Limiting excess salt, highly processed foods, sugary beverages and foods high in saturated or trans fats may support cardiovascular and metabolic health.

Physical activity can also support blood glucose management, blood pressure, cholesterol and overall fitness. Many adults are advised to work towards at least 150 minutes of moderate-intensity aerobic activity per week, where suitable for their health and ability. Activity should be adapted to individual needs, particularly for people with cardiovascular symptoms or other medical conditions.

Other important measures include:

• Avoiding tobacco and seeking support to stop smoking.
• Taking prescribed medication as directed.
• Attending recommended diabetes follow-up appointments.
• Monitoring blood glucose and other health measures as advised.
• Maintaining healthy sleep habits.
• Discussing weight management and other relevant risk factors with a healthcare professional.

A suitable long-term plan should consider personal preferences, existing conditions, treatment requirements and the person’s ability to maintain these changes.

Frequently Asked Questions

1. Can controlling my blood sugar reverse existing heart damage?

Managing blood glucose can help reduce the risk of diabetes-related complications, but it cannot be assumed to reverse existing coronary plaque or other established heart damage. Cardiovascular risk reduction may also require management of blood pressure, cholesterol, smoking and other contributing factors. The appropriate plan depends on the individual’s condition, and established heart disease may require additional treatment.

2. Do all people with diabetes eventually develop heart disease?

No. Diabetes increases cardiovascular risk, but heart disease is not inevitable. Risk varies according to factors including the type and duration of diabetes, blood pressure, cholesterol, smoking, kidney function, family history and other medical conditions. Appropriate diabetes care and management of cardiovascular risk factors can help reduce risk, although they cannot eliminate it completely.

3. How often should a person with diabetes see a cardiologist?

There is no single cardiology appointment schedule that is appropriate for every person with diabetes. Regular diabetes care should include assessment of cardiovascular risk factors and review of relevant symptoms. A cardiologist may be involved when symptoms, established cardiovascular disease, abnormal findings or other clinical circumstances warrant specialist assessment. Routine annual stress testing or cardiac imaging is not automatically recommended for everyone with diabetes.

4. Does insulin therapy harm the heart?

Insulin is an established treatment for diabetes and may be necessary to manage blood glucose in certain circumstances. It should not be assumed that prescribed insulin itself causes heart damage. As with other treatments, insulin requires appropriate dosing and monitoring because it can cause low blood glucose and other treatment-related problems. Do not stop or change insulin without guidance from the prescribing healthcare professional.

Key Takeaway: Diabetes and Cardiovascular Health

Diabetes is associated with an increased risk of heart and blood vessel conditions, but the level of risk and the appropriate preventive measures vary between individuals.

Managing blood glucose, blood pressure and cholesterol, avoiding tobacco, maintaining suitable physical activity and following an individualised treatment plan can help support cardiovascular health. Testing should be selected according to symptoms, risk factors and clinical findings rather than automatically prescribed to every person with diabetes.

Recognising possible heart attack symptoms is also important because some people, including those with diabetes, may experience less typical symptoms. Suspected heart attack symptoms require emergency medical assessment.