Insulin is a hormone produced by the pancreas that "unlocks" the body's cells, allowing the sugar go from the blood and into the cells. The cells in the body use this sugar for energy.
When the body does not make any or enough insulin, or when the cells are unable to use the insulin correctly, blood sugar levels go up.
Hyperglycemia and diabetes
Hyperglycemia is common in people with diabetes. People with prediabetes are also at an increased risk. Prediabetes refers to blood sugar levels that are higher than normal but are not as high as they are for diabetes.
Diabetes causes high blood sugar levels two main ways. Either there is a lack of insulin, as is the case with type 1 diabetes, or the body doesn't respond properly to insulin. In prediabetes, it is usually due to the cells not responding correctly. In type 2 diabetes, it is usually a combination.
There are several causes of hyperglycemia that are related to diabetes:
There are many causes of hyperglycemia that are related to diabetes.
- Eating too many carbohydrates
- Exercising less than usual
- Taking less medication than usual
Though many causes are related to diabetes, there are additional factors that can contribute to hyperglycemia:
- Certain medications such as steroids
- Other pancreatic diseases
Illness and stress can trigger hyperglycemia because the hormones that are produced to combat illness or stress can also cause blood sugar to rise. People do not have to have full-blown diabetes to develop hyperglycemia due to a severe illness.
People with diabetes may need to take extra diabetes medication to keep their blood sugar levels stable during illness or stress.
Hyperglycemia can be very dangerous because it often doesn't cause symptoms. People who have had type 2 diabetes for several years may not have any symptoms despite their blood sugar being raised.
The longer that blood sugar levels stay high, the more serious the symptoms can become.
Early signs and symptoms include:
- High levels of sugar in the urine
- Frequent urination
- Increased thirst
- Increased hunger
- Blurry vision
- Cuts or sores that won't heal (with type 2 diabetes)
- Weight loss (with type 1 diabetes)
Complications of hyperglycemia
If allowed to go untreated, hyperglycemia can cause toxic acids called ketones to build up in the blood and urine. This can lead to a condition called ketoacidosis or a diabetic coma.
If high blood levels are left untreated, they can lead to severe complications such as a coma.
Since ketoacidosis develops in response to a lack of insulin in the body, only people with type 1 diabetes are at risk. Ketoacidosis is rare for people with type 2 diabetes.
Without insulin, the body is unable to use sugar for fuel, causing it to break down fat instead to use for energy. Waste products called ketones are produced when the body breaks down fat. The body is unable to handle large amounts of ketones in the bloodstream, so it tries to remove them through the urine.
Ketoacidosis is a life-threatening condition and requires immediate treatment. Signs and symptoms to look for include:
- Fruit-smelling breath
- Nausea and vomiting
- Shortness of breath
- Dry mouth
- Stomach pain
Another complication is hyperglycemic hyperosmolar syndrome. This occurs when the body produces insulin that does not work properly. Blood sugar levels can become very high, and the body cannot use either sugar or fat for energy.
Sugar spills into the urine, causing an increase in urination. If left untreated, diabetic hyperglycemic hyperosmolar syndrome can be life-threatening and lead to severe dehydration and coma.
This syndrome is quite rare and affects only people with type 2 diabetes, usually the elderly. It is most likely to occur when people are sick and have difficulty staying hydrated.
The signs and symptoms of this syndrome include dry mouth, high fever (over 101ºF), sleepiness, and high blood sugar levels.
Hyperglycemia can cause other serious long-term complications:
- Vessel damage that increases the risk of heart disease and stroke
- Nerve damage
- Kidney damage or kidney failure
- Damage to the blood vessels of the retina, potentially leading to blindness
- Clouding of the normally clear lens of your eye (cataract)
- Feet problems that can lead to serious infections
- Bone and joint problems
- Skin problems, including infections and non-healing wounds
- Tooth and gum infections
Hyperglycemia is treated according to specific symptoms. It is important to note that not everyone will have all of the symptoms.
People with diabetes should use a glucose meter to monitor their blood sugar levels.
One of the main ways to check for hyperglycemia is to keep an eye on blood sugar levels. A doctor can discuss blood sugar ranges with patients.
The American Diabetes Association suggest the following blood sugar targets for most nonpregnant adults with diabetes:
- Before a meal: 80-130 milligrams per deciliter
- Around 1-2 hours after beginning of the meal: Less than 180 milligrams per deciliter
Ranges can vary a little depending on age and other medical conditions such as a heart, lung, or kidney disease. Ranges can also vary in people who are pregnant or experiencing complications from diabetes.
All people with diabetes should use a glucose meter to monitor their blood sugar at home and make sure they stay within their goal range. Home monitoring allows them to notice any changes and immediately report problems to their physician.
If they have any symptoms of hyperglycemia, a doctor can adjust their medicine accordingly. Doing so can bring their blood sugar back down to a safe level.
There are also over-the-counter urine ketones test kits for people with type 1 diabetes whose blood sugar level is 240 milligrams per deciliter. If they also experience any of the symptoms listed above, a positive test means that their body may be in the early stages of diabetic ketoacidosis.
Emergency treatment at the emergency room may be needed if the signs and symptoms of hyperglycemia complications appear. Patients may receive fluids orally or through IV until they are rehydrated.
Fluid and electrolyte replacement and insulin therapy are the two treatment options for patients. Electrolytes are minerals in the blood that are required for tissues to function properly. Severe hyperglycemia can lead to lower levels of electrolytes in the blood.
For everyday monitoring, doctors can check blood sugar levels or can conduct an A1C test. This test indicates an average blood sugar level for the past 2-3 months.
The A1C works by measuring the percentage of blood sugar in the bloodstream that is attached to hemoglobin, the oxygen-carrying protein in red blood cells.
In addition to talking to a doctor about managing blood sugar levels, there are things that people can do to help avoid hyperglycemia:
- Stay active: Regular exercise has been proven to be an effective way to control blood sugar. People shouldn't exercise if they have ketones in their urine, however, because they can drive blood sugar higher.
- Medication: Patients should always take medication as directed. A doctor can adjust it if needed.
- Eating: Doctors or dietitians can help patients develop a healthy diabetes eating plan.
- Manage stress and illness.
Diabetes is a very serious condition. It is important for people with diabetes to keep track of blood sugar, stay within their target blood sugar levels, follow an eating plan, exercise, and always take their medicine.
Jessica Pena's daughter was diagnosed with type 1 diabetes as a toddler. Here, she describes a typical day to the American Diabetes Association:
"From the minute we wake up, I check her blood glucose. [...] She basically leads a normal life; I just have to monitor her blood glucose levels throughout our daily lives which has become our top priority!"
People should report anything abnormal to their doctor. This can help people to prevent hyperglycemia as well as receive early treatment and prevent long-term complications.