Prediabetes: Symptoms, Causes, Risk Factors, Prevention (2024)

As its name implies, prediabetes is a condition that precedes developing diabetes. Here the blood sugar levels are higher than normal but haven’t crossed the threshold associated with full-blown diabetes.

According to the Centers for Disease Control and Prevention (CDC), around 38% of the US population aged 18 or older have prediabetes. In the UK, 13.6 million people are at increased risk of type 2 diabetes  (Publications Parliament UK)

Such alarming statistics call for critical preventive efforts to detect early warning signs and prevent disease progression.

The good news is that developing type 2 diabetes isn’t inevitable, and early detection of prediabetes can help you make essential changes.

With positive lifestyle changes, adopting a healthy diet, and maintaining normal blood glucose levels, prediabetes symptoms are kept in check. You'll be able to read on to learn all you need to know about prediabetes.

The development of prediabetes is similar to the underlying metabolic changes associated with type 2 diabetes. Both conditions can be attributed to insulin resistance, where the circulating hormone levels aren’t sufficient to carry out its intended function.

The pancreas secretes a hormone called insulin, which helps the body cells utilize glucose and generate energy. If insulin levels are below normal or the cells resist the insulin effects, the circulating blood glucose levels go up.

The blood sugar ranges in prediabetes are lower when compared to type 2 diabetes. That’s why prediabetes seldom presents symptoms. 

Nevertheless, here are some warning signs that raise the suspicion of abnormal blood glucose levels and warrant seeking medical advice.

One of the first signs that predict progression to type 2 diabetes is unexpected weight loss.

Insulin resistance prevents the body’s cells from utilizing circulating blood sugar. Instead, the body starts burning muscles and fat tissue, which translates into weight loss.

According to the European Centre for Disease Prevention and Control (ECOC), losing 10 lbs or more throughout 6 to 12 months without any changes in physical activity or dietary habits warrants a fasting blood sugar test.

Early detection of impaired glucose tolerance can help reverse prediabetes.

An abnormally high blood glucose level can lead to a continuous feeling of hunger. Since blood sugar can’t be properly utilized to generate energy, the hunger center in the brain is activated in response.

Bear in mind that increased appetite indicates chronically abnormal blood sugar levels and requires further testing to prevent diabetes complications like the development of heart disease, blood vessel injury, and increased risk of high blood pressure.

Dry mouth is among the first alarming signs noticed by diabetes patients. The condition might be associated with foul mouth odour, mucosal ulcers, and poor teeth hygiene. This can lead to difficulties when chewing or swallowing.

To maintain a normal plasma concentration, a person with a higher-than-average blood sugar level always tends to be thirsty.

The excess fluid intake balances out the abnormal blood sugar levels. However, such a compensatory response is temporary, and the expanded plasma volume leads to more frequent urination.

According to the American Diabetes Association (ADA), a blood test should be performed twice to confirm the diagnosis of prediabetes. 

Different blood tests have different cutoff points. Your primary care physician might order one of these blood sugar tests when prediabetes is suspected.

The symptoms of prediabetes are vague and non-specific, especially early on in the condition. 

The hemoglobin A1C testing gives an overview of the blood sugar levels over the past two or three months. Such a test doesn’t require prior preparations and can be done without fasting.

In terms of prediabetes test values in the U.S., a range between 5.7% to 6.4% warrants the diagnosis of prediabetes.

In the UK, if your HbA1c level is between 42mmol/mol (6%) – 47mmol/mol (6.4%) you are at a higher than normal risk of developing type 2 diabetes (Diabetes UK - What is HbA1c?).

Again, the test needs to be repeated to confirm the diagnosis.

The oral glucose tolerance test requires fasting and involves checking your blood sugar levels twice during the same appointment. Your fasting blood sugar level is recorded, and you’re asked to drink a sugary solution. Two hours later, another reading is taken.

For a diagnosis of prediabetes, the blood sugar levels have to fall between 140 to 199 mg/dl two hours after consuming the oral sugary drink.

A simple fasting plasma glucose test can help diagnose people with prediabetes. You’ll be asked to fast for at least eight hours or overnight. Then, a blood sample will be drawn, and blood sugar levels will be estimated.

A value of 100 to 125 mg/dl indicates prediabetes. Impaired fasting glucose can be the only sign of prediabetes, which speaks to why a high level of suspicion is always needed when it comes to detecting subtle health conditions.

The genetic and lifestyle factors that increase the risk of getting type 2 diabetes also raise the odds of developing prediabetes. 

Here are some of the factors to keep an eye out for:

• Age: The risk of developing prediabetes increases in people older than 45.

• Body Weight: High blood sugar is seen in patients with a Body Mass Index (BMI) over 25. For this reason, a successful diabetes prevention program always targets such demographic groups and encourages weight loss to minimize the potential of developing metabolic syndrome.

• Diet: According to the CDC’s National Diabetes Prevention Program, eating processed meat and artificial sweeteners increases the risk of prediabetes. Furthermore, a balanced diet can help you maintain a healthy weight and avoid the negative impacts of obesity.

• Physical Activity: A sedentary lifestyle is the hallmark of people with prediabetes.

• Obstructive Sleep Apnea: Besides having difficulty breathing while sleeping, people with obstructive sleep apnea are at a high risk of developing insulin resistance.

• Gestational Diabetes: Developing diabetes during pregnancy increases the risk of prediabetes in both the mother and the child. Such high-risk groups require more frequent blood sugar monitoring to early detect deviations from the normal blood sugar range.

• Polycystic Ovary Syndrome: Such a condition presents in women with menstrual abnormality, insulin resistance, and abnormal heart growth. Darkened skin can also be seen, especially in the skin folds around the armpits, neck, elbows, and knees.

• Smoking: Tobacco smoking is associated with high blood pressure and abnormal cholesterol profile, increasing the risk of prediabetes.

If left untreated, prediabetes can progress into type 2 diabetes, which presents with a dramatic set of complications. It’s worth noting that such conditions are avoidable by maintaining normal blood sugar levels and making positive lifestyle changes.

High blood glucose levels lead to nerve damage, preferentially affecting the peripheral nerves of the hands and feet. This leads to what is known as glove and stocking pain, where patients feel tingling and numbness sensation.

The nerve damage can also affect other systems leading to sexual dysfunction, digestive and kidney diseases, and urinary tract abnormalities.

Uncontrolled blood glucose levels over an extended period can damage the retina's blood vessels, which is the eye's light-sensitive layer.

Such a condition can first present with blurry vision and floaters that can progress to complete vision loss.

Poor blood circulation and loss of sensation in the feet increase the risk of foot complications in diabetic patients. Such patients are more susceptible to developing ulcers and prolonged infections due to slow wound healing.

Severe cases can progress to gangrene that requires foot amputation. This shows how follow-up visits and close monitoring of patients with type 2 diabetes are crucial to prevent debilitating complications.

A healthy lifestyle is crucial in the prevention of prediabetes. 

Let’s highlight some simple steps that you can follow to avoid developing such a condition:

• Exercise regularly to lose excess weight

• Maintain normal blood pressure and cholesterol profile

• Quit smoking

• Adopt a healthy range of physical activity in your daily routine

Prediabetes can lead to serious health conditions like heart disease, stroke, and the progression of type 2 diabetes. This doesn’t have to be the case if early blood glucose monitoring is performed when the suspicion index is high.

Also, adopting positive lifestyle changes like regular exercise and a healthy diet can reverse prediabetes and promote well-being!