5.1 Define the term ‘hyperglycaemia’

This guide will help you answer 5.1 Define the term ‘hyperglycaemia’.

Hyperglycaemia is a medical term that means an abnormally high level of glucose (sugar) in the blood. The word comes from Greek: “hyper” means high, “glyc” refers to sugar, and “aemia” means in the blood. So, hyperglycaemia is simply having too much sugar in the bloodstream.

Blood glucose comes from the carbohydrates in food and drinks. The body uses glucose as its main source of energy. Insulin, a hormone produced by the pancreas, helps move glucose from the blood into the cells. If insulin is lacking or not working well, glucose stays in the blood and levels rise.

Hyperglycaemia affects many people, especially those who have diabetes. Diabetes is a long-term condition that changes how the body processes blood glucose. People with diabetes can have high blood glucose if their insulin is too low, their medication is not working, or they eat too much sugar or carbohydrates.

What is Blood Glucose?

Blood glucose is the amount of sugar present in the blood at any time. The body needs some glucose to function. Muscles, the brain, and organs use glucose for energy. Blood glucose levels change throughout the day based on food intake, exercise, stress, and insulin levels.

Normal blood glucose levels are:

• Before meals: 4–7 mmol/L (millimoles per litre)
• Two hours after meals: under 8.5 mmol/L

When the level goes above these targets, it is described as hyperglycaemia.

Causes of Hyperglycaemia

Hyperglycaemia happens for different reasons. People with diabetes are most at risk, but it can affect anyone in certain circumstances.

Common causes include:

• Not taking enough insulin or diabetes tablets
• Eating too much carbohydrate-rich food
• Infection or illness (which makes the body release stress hormones)
• Physical or emotional stress
• Being inactive
• Some medicines that raise blood glucose
• Hormonal changes, such as during periods (menstruation) or puberty

Hyperglycaemia is not a disease alone—it is a sign something is changing in the body, often related to diabetes.

Signs and Symptoms of Hyperglycaemia

When blood glucose is high, the body tries to get rid of excess sugar. Early signs are easy to miss, but recognising them helps prevent complications.

The key symptoms include:

• Feeling very thirsty (polydipsia)
• Passing large amounts of urine (polyuria)
• Feeling tired or weak
• Blurred vision
• Headaches
• Dry mouth and skin
• Unusual hunger

If blood glucose remains very high for days or weeks, other issues can occur:

• Unintentional weight loss
• Increased risk of infections, such as thrush or urinary tract infections
• Slow healing of wounds and cuts

In people with diabetes, these symptoms may appear suddenly or build up slowly.

Risks Linked to Hyperglycaemia

Short-term hyperglycaemia may not cause harm if it is treated quickly. But if blood glucose stays high, it can lead to serious medical problems.

Risks include:

• Diabetic ketoacidosis (DKA) – most common in people with type 1 diabetes. The body begins to break down fat for energy, creating harmful chemicals called ketones. Signs are nausea, abdominal pain, rapid breathing, and fruity-smelling breath.
• Hyperosmolar Hyperglycaemic State (HHS) – occurs in type 2 diabetes, usually in older adults. The blood becomes very thick (concentrated) due to high glucose. Symptoms include severe dehydration and confusion.
• Increased risk of long-term harm to blood vessels, eyes, kidneys, and nerves (if hyperglycaemia is frequent)

If someone has high blood glucose for a long time, these risks grow. Quick action and good management help prevent them.

Hyperglycaemia and Diabetes

Diabetes is a major cause of hyperglycaemia. There are three main types of diabetes:

• Type 1 diabetes: The body cannot make insulin, so blood glucose rises very quickly without insulin injections.
• Type 2 diabetes: The body does not make enough insulin or cannot use it properly (insulin resistance). This causes blood glucose to build up.
• Gestational diabetes: Diabetes that develops during pregnancy, leading to high blood glucose. It usually goes away after birth but needs careful monitoring.

People with diabetes need to check their blood glucose often. Self-testing helps to catch any rise in glucose early.

How Hyperglycaemia is Measured

Hyperglycaemia is measured using a blood test. The simplest test uses a small drop of blood from a finger. A special device called a blood glucose meter shows the blood glucose level within seconds.

Some blood tests used to check for hyperglycaemia are:

• Capillary blood glucose test: quick check using a finger-prick
• Fasting blood glucose: test after not eating for at least 8 hours
• Oral glucose tolerance test: measures blood glucose after drinking a sugary liquid
• HbA1c blood test: shows average glucose control over the past 2–3 months

A reading above 7 mmol/L before eating and above 8.5 mmol/L after eating usually means hyperglycaemia.

Preventing Hyperglycaemia

Preventing high blood glucose is a key part of care for people with diabetes. Steps that help include:

• Taking insulin or medication as prescribed
• Eating a balanced diet with regular meals
• Being active every day, such as walking or swimming
• Checking blood glucose levels as advised by a health professional
• Managing stress and illness carefully

If someone suspects hyperglycaemia, acting early is safest. Adjusting medication, drinking more water, and speaking to a nurse or GP can all help stop it from getting worse.

Managing Hyperglycaemia in Care Settings

Care workers play an important role. You may notice the first signs of high blood glucose and raise concerns.

Actions to take:

• Observe for symptoms (thirst, frequent urination, tiredness)
• Support regular blood glucose testing (if the person can self-test)
• Encourage healthy meals and snacks
• Help people take their medication on time
• Keep accurate records of symptoms, test results and actions taken
• Report changes to your supervisor, nurse, or GP

If someone has severe symptoms, such as vomiting, deep breathing, confusion, or falls unconscious, treat this as a medical emergency and get help straight away.

Difference Between Hyperglycaemia and Hypoglycaemia

Hyperglycaemia sounds similar to hypoglycaemia. They are opposites.

• Hyperglycaemia: High blood glucose
• Hypoglycaemia: Low blood glucose

Both are serious and can harm people with diabetes. Good care, regular checks, and early action keep people safe.

Complications Linked to Hyperglycaemia

Short-term complications:

• Dehydration: Increased urination causes loss of fluids from the body.
• Fatigue: The body cannot use glucose without insulin, leading to tiredness.
• Infections: High glucose feeds bacteria, making skin, bladder and mouth infections more likely.

Long-term complications (if not controlled):

• Eye problems: High glucose damages tiny blood vessels in the eyes, affecting vision.
• Kidney disease: Damaged kidneys filter waste less well.
• Nerve damage: High glucose injures nerves, causing tingling or numbness.
• Heart attacks and strokes: High blood glucose raises the risk of these events.

Good control of blood glucose prevents most complications.

Monitoring and Support for People at Risk

Anyone caring for people with diabetes should know the signs to watch for. Support must be person-centred and agreed with the individual.

Key steps include:

• Encouraging routine blood glucose monitoring
• Helping keep a food and symptom diary
• Making sure prescribed medication is taken
• Watching for symptoms and reporting worries to nurses or doctors
• Supporting efforts to keep well hydrated, especially during hot weather or illness

Emotional support matters too. Hyperglycaemia can make people feel unwell and worried about their health. Good communication and reassurance are helpful.

Special Considerations for Different Groups

Some people face extra risk or have different needs.

Older adults: They may have weaker symptoms, feel confusion, or develop dehydration more easily.

Children: Parents and carers must be alert. Young children may not recognise the signs of high blood glucose.

Pregnant women: Gestational diabetes can harm both mother and baby if hyperglycaemia is not managed.

People with learning disabilities: Staff support and education can make a big difference by spotting signs early and making healthy choices together.

How to Respond to Hyperglycaemia

If you think someone you support may have hyperglycaemia:

• Talk to them about how they feel
• Check for common symptoms
• Suggest a blood glucose check if appropriate
• Record and report all findings
• Encourage water intake (unless the person is on fluid restriction)
• Never ignore new or worsening symptoms

If confusion, vomiting, unconsciousness, or deep sighing breathing develop, seek emergency medical help.

Legal and Best Practice Framework

UK health care staff must work within the law and standards set by regulators.

Relevant frameworks include:

• The Health and Social Care Act 2008: Requires safe and effective care
• NICE Guidelines for diabetes: Set safe blood glucose targets and treatment
• Data Protection Act 2018: Protects the confidentiality of medical information
• Duty of care: Everyone must act in the best interests of those they support

Training, ongoing supervision and seeking specialist advice helps all staff provide safe, high-quality care.

Supporting Self-Management

Where possible, supporting people to manage their own blood glucose levels works best.

Tips:

• Give clear information about how and when to test blood glucose
• Reinforce healthy eating advice
• Talk through how to use medication, insulin pens or pumps safely
• Discuss reasons for high blood glucose and ways to adjust lifestyle choices
• Encourage open communication about worries or challenges

Using Technology for Management

Many people use technology to monitor and manage hyperglycaemia.

These include:

• Blood glucose meters
• Flash glucose monitors (show real-time readings)
• Apps for recording food and blood glucose data

Staff may help use these tools, interpret results and share information safely with the wider team.

Hyperglycaemia Definition

To define hyperglycaemia simply: it is higher than normal blood glucose. It matters most in people with diabetes, who rely on insulin or medication to control their blood sugar. Carers must understand the risk factors, signs and symptoms, causes, and steps to respond.

Supporting good diabetes management helps reduce the risk of hyperglycaemia and its complications. Prompt action, regular monitoring, and clear reporting keep people safe and supported.

Final Thoughts

Hyperglycaemia is a common issue for people living with diabetes. High blood glucose is not always easy to spot but can cause significant difficulties if ignored. Simple lifestyle changes, medication, and support from trained workers all play an important role in keeping people healthy.

As a health or care worker, understanding what hyperglycaemia means gives you the knowledge needed to keep people safe. Watching for symptoms, supporting regular checks, and responding to changes quickly makes a real difference. Ongoing learning, good teamwork and a person-centred approach mean you play a key part in improving the lives of those living with or at risk of hyperglycaemia.