Diabetes and cardiovascular health

Understanding diabetes and your heart

Diabetes means the body cannot keep blood glucose (sugar) within a normal range, either because it does not make enough effective insulin or cannot use the insulin it makes. Glucose that stays high over months and years does not only affect energy and thirst — it steadily damages blood vessels throughout the body, including the arteries that supply the heart, brain, kidneys, eyes and feet. This is why diabetes is treated as much as a cardiovascular condition as a blood-sugar one, and why heart risk is assessed at every diabetes review, not only when symptoms appear.

High glucose injures the delicate inner lining of arteries (the endothelium), making it easier for fatty deposits (plaque) to build up and narrow the vessel — a process called atherosclerosis. The same process that narrows the arteries supplying the heart (raising the risk of heart attack) also affects the arteries to the brain (stroke), the legs (peripheral artery disease) and the kidneys. Diabetes rarely travels alone: it commonly appears alongside high blood pressure, abnormal cholesterol and excess weight, and together these compound cardiovascular risk far more than any one of them alone. In some people, the heart muscle itself becomes stiffer and less efficient at pumping over time (sometimes called diabetic cardiomyopathy), even without major artery blockage.

What you may notice

One of the most important things to understand about diabetes and the heart is that warning signs can be blunted or absent. Diabetes can damage the small nerves that normally carry pain signals (a form of nerve damage called autonomic neuropathy), so a heart problem that would cause obvious chest pain in someone else may cause only mild discomfort, or none at all, in a person with diabetes. This is sometimes called a "silent" heart problem, and it is a key reason routine cardiovascular screening matters even when you feel well.

• ●Chest discomfort, pressure or tightness — may be mild, unusual, or absent
• ●Unusual tiredness or breathlessness with activities that were previously easy
• ●Swelling of the feet, ankles or lower legs
• ●Indigestion-like discomfort, nausea or sweating not clearly linked to food
• ●Cramping pain in the calves when walking that eases with rest (a possible sign of narrowed leg arteries)
• ●Symptoms of related complications — blurred vision, numbness or tingling in the feet, or protein noticed in urine testing

Because symptoms can be subtle, many people with diabetes are advised to have cardiovascular risk assessed on a schedule, rather than waiting for symptoms to prompt a visit.

Why diabetes affects the heart

Several linked processes explain why diabetes raises cardiovascular risk.

Artery damage from high glucose

Persistently high glucose damages the inner lining of blood vessels and promotes fatty plaque build-up. Over years this narrows arteries throughout the body, including those supplying the heart muscle itself.

A cluster of risk factors

Diabetes commonly occurs together with high blood pressure, abnormal cholesterol and central weight gain — sometimes referred to together as cardiometabolic risk. Each factor adds to the others, so overall risk is often higher than any single measurement suggests.

Changes in the heart muscle itself

Independent of artery narrowing, long-standing diabetes can gradually stiffen and weaken the heart muscle, affecting how well it fills and pumps.

Nerve damage affecting the heart

Diabetes can also affect the nerves that regulate heart rate and blood pressure responses, and the nerves that carry pain signals — part of why some heart problems in diabetes cause fewer or milder symptoms than expected.

Who is at higher cardiovascular risk

These factors increase cardiovascular risk in people with diabetes, and are worth reviewing at every visit:

• ●How long diabetes has been present, and how well glucose has been controlled over time
• ●High blood pressure — very common in Nigeria and often undiagnosed
• ●Abnormal cholesterol levels
• ●Excess weight, particularly around the waist
• ●Smoking or tobacco use
• ●Kidney disease or protein detected in urine testing
• ●A family history of heart disease
• ●Low physical activity levels
• ●Increasing age

What happens if this goes untreated

Most cardiovascular complications of diabetes develop gradually and are preventable or delayable with consistent care — but left unaddressed, they can be serious.

Heart attack. Narrowed or blocked arteries can suddenly cut off blood supply to part of the heart muscle; in diabetes this may present with fewer or milder warning symptoms than usual.

Heart failure. Artery disease and changes within the heart muscle itself can combine to reduce the heart's pumping efficiency over time, causing breathlessness and fluid retention.

Stroke. The same artery-narrowing process that affects the heart can affect the arteries supplying the brain.

Peripheral artery disease. Narrowed leg arteries reduce blood flow to the feet and legs, contributing to poor wound healing and, in advanced cases, risk to the limb.

Kidney disease. The heart and kidneys are closely linked; diabetes affecting the kidneys can in turn worsen blood pressure and fluid balance, adding further strain on the heart.

How Cardiocare finds the cause

Assessing cardiovascular risk in diabetes draws on several linked checks, usually done together rather than in isolation:

• 01
  History and examination. Review of symptoms, how long diabetes has been present, other conditions, and a physical examination including pulses and blood pressure.
• 02
  Glucose control review. Recent glucose readings and HbA1c, a blood test reflecting average glucose over the preceding weeks to months.
• 03
  Blood pressure measurement. Checked at every visit; sustained high readings are treated as a cardiovascular risk factor in their own right.
• 04
  Cholesterol (lipid) profile. A blood test measuring different types of cholesterol and fats that influence artery health.
• 05
  Kidney function and urine testing. Blood tests and a urine sample checking for early protein leakage, an early marker of kidney and cardiovascular risk.
• 06
  12-lead ECG. A painless recording of the heart's electrical activity, taking minutes.
• 07
  Echocardiogram. A painless ultrasound scan of the heart's structure and pumping function, used where heart failure or muscle changes are suspected.
• 08
  Exercise or stress testing. Where indicated, assesses how the heart responds under controlled exertion.

Because symptoms can be mild or absent, these checks are often scheduled proactively as part of ongoing diabetes care rather than only in response to symptoms.

How cardiovascular risk in diabetes is treated

Protecting the heart in diabetes usually means treating several things together, not glucose alone.

Lifestyle measures

Sustainable changes to eating pattern, regular safe physical activity, weight management where relevant, and stopping smoking all reduce cardiovascular risk meaningfully, alongside medical treatment.

Medicines, by class

Your clinician will discuss which options suit you; several classes of medicine work together, often started at the same time rather than in sequence:

• ●Glucose-lowering medicines — several different classes exist; some are chosen specifically because they also offer heart and kidney protection
• ●Blood pressure medicines — bring blood pressure into a safer range and protect the kidneys
• ●Cholesterol-lowering medicines (statins) — reduce the fatty plaque process in artery walls
• ●Antiplatelet medicine — for selected patients, reduces the risk of clot-related events such as heart attack

Procedures

Where arteries are significantly narrowed, procedures available through Cardiocare's on-site cardiac catheterisation ("cath") laboratory or cardiac surgery service may be recommended, such as angioplasty and stenting or bypass surgery, matched to what the imaging shows and your overall health.

Living well with diabetes and heart risk: everyday self-care

Day-to-day habits make a real difference alongside medical treatment:

• ✓Take glucose, blood pressure and cholesterol medicines consistently, even when feeling well
• ✓Attend scheduled screening for the eyes, kidneys, feet and heart
• ✓Build meals around vegetables, fibre and appropriate portions of swallow, rice and other staples, rather than cutting them out entirely
• ✓Check your feet regularly for cuts, blisters or wounds that are slow to heal, and seek prompt attention for any
• ✓Stay physically active in ways that are safe for you
• ✓Be cautious with herbal or "natural" diabetes remedies — they are not a substitute for prescribed treatment and can occasionally be harmful

Preparing for your appointment

What to bring

• ✓A record of recent home glucose readings, if you monitor at home
• ✓A list of all medicines you take, including herbal and over-the-counter products
• ✓Previous blood test results, ECGs or hospital letters
• ✓Your HMO card or payment details
• ✓A valid means of identification

What we will ask

How long you have had diabetes, recent glucose control, any symptoms of chest discomfort, breathlessness or leg pain, other conditions such as high blood pressure, and all medicines you currently take.

Questions worth asking us

• ●What is my current cardiovascular risk?
• ●Which tests do I need, and how often?
• ●Should any of my medicines change?
• ●What symptoms should prompt me to come back sooner?