Type 2 Diabetes
This animation describes insulin resistance, an underlying cause of type 2 diabetes. It explains the roles of glucose and the hormone insulin in our body. Symptoms of diabetes are reviewed and various health complications that type 2 diabetes can lead to if left untreated.
What are the other Names for this Condition? (Also known as/Synonyms)
- Adult-Onset Diabetes
- Diabetes - Type 2
- Noninsulin-Dependent Diabetes
What is Type 2 Diabetes? (Definition/Background Information)
- Type 2 Diabetes is a chronic disease in which the blood contains high levels of glucose (sugar), the body’s main source of fuel.
- With this disorder, the body either resists the effects of insulin, a hormone, responsible for regulating sugar in cells or does not produce sufficient amounts to have a normal glucose blood level.
- Type 2 Diabetes is the most common type of Diabetes.
- There is no cure for this condition; however, it can be managed by eating well, exercising, and by maintaining a healthy body weight.
Who gets Type 2 Diabetes? (Age and Sex Distribution)
- Type 2 Diabetes affects men and women equally, occurring mostly in individuals over 45 years old.
- Type 2 Diabetes is seen to be increasingly affecting children, due to the increasing prevalence of child obesity.
- Certain ethnic groups, including African-Americans, Hispanic Americans, Asian Americans, and Native Americans are at a higher risk for developing Diabetes.
What are the Risk Factors for Type 2 Diabetes? (Predisposing Factors)
The risk factors for Type 2 Diabetes include:
- Family history of Diabetes: One's risk for Type 2 Diabetes increases, if a parent or sibling has the condition
- Race: Several races including Afro-Americans, Hispanics, American Indians, and Asian-Americans are more likely to suffer from the condition
- Age greater than 45 years, with risk increasing significantly after 65 years of age
- Diabetes during a previous pregnancy
- Women who have given birth to a baby weighing over 9 pounds
- HDL cholesterol under 35 mg/dL
- High blood levels of triglycerides, about 250 mg/dL or above
- High blood pressure, greater or equal to 140/90 mmHg
- Lessened glucose tolerance
- Having gestational diabetes when pregnant, can increase ones risk of developing Type 2 Diabetes in the future
- High alcohol intake
- Low activity levels: Physical activity aids in controlling weight. It uses up glucose for energy, helping to lower and maintain blood glucose levels
- Metabolic syndrome
- Polycystic ovarian syndrome
- Poor diet of high fat and high calories
- Fat distribution: Having an excess amount of fat stored primarily in the abdominal region, increases the risk for Type 2 Diabetes
- Excess body weight: The more fatty tissues an individual has, the more resistant their cells become to insulin
- A condition called acanthosis nigricans, which causes dark, thickened skin around the neck and armpits
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Type 2 Diabetes? (Etiology)
- The most common causes of Type 2 Diabetes are obesity and a lack of physical activity. It is responsible for nearly 95% of all Diabetes cases in the United States.
- Type 2 Diabetes is a complex result of the way the body produces or utilizes insulin. Insulin is necessary to move blood sugar into the cells, where it is stored for later energy use. Individuals with Type 2 Diabetes do produce insulin; however, the pancreas either secretes not enough insulin or the body has trouble in properly identifying the insulin, in order to utilize it properly.
- A Type 2 Diabetes individual’s liver, fat, and muscle cells do not respond correctly to insulin. This is known as insulin resistance. Therefore, the blood glucose (sugar) does not properly get stored into these cells for later energy use.
- Without sugar integrating into these cells, high levels of glucose build up in the bloodstream, called hyperglycemia.
- The Type 2 diabetic condition often occurs gradually, over time. The majority of people diagnosed with the disease are overweight. An increased amount of body fat makes it difficult for the body to utilize insulin properly.
- However, Type 2 Diabetes may also develop in thin people, most commonly in the elderly adults.
What are the Signs and Symptoms of Type 2 Diabetes?
In most cases, individuals with Type 2 Diabetes have no initial symptoms. This could last for several years.The early signs of Type 2 Diabetes due to high blood sugar may include:
- Bladder, kidney, skin, or other infections that are more frequent,and/or heal slowly
- Increased hunger and thirst
- Increased urination
- Blurred vision: If blood sugar becomes too high, it is possible for fluid to be pulled from the lenses of the eyes, affecting one’s ability to focus clearly
- Erectile dysfunction
- Unexplainable weight loss
- Pain or numbing of the feet and hands
- Loss of consciousness (rare)
Other symptoms of Type 2 Diabetes may include:
- Slow-healing of sores
- Itchy skin, usually around vaginal or groin area
- Frequent yeast infections
- Recent weight gain
- Velvety dark skin changes of neck, armpit, and groin, known as acanthosis nigricans
- Numbness and tingling of hands or feet
How is Type 2 Diabetes Diagnosed?
A physician may suspect an individual has Diabetes when their blood sugar level exceeds 200 mg/dL. Type 2 Diabetes is diagnosed with the following blood tests:
- Fasting blood glucose level:If higher than 126 mg/dL, two times
- Oral glucose tolerance test: If the glucose level exceeds 200 mg/dL after 2 hours
Hemoglobin A1c test, with values as noted below:
- Normal: Below 5.7%
- Pre-diabetes: Between 5.7% and 6.4%
- Diabetes: 6.5% or above
A physician can perform several examinations in order to monitor the state of Diabetes and prevent medical issues associated with Diabetes, such as:
- Check the skin and bones on the feet and legs; check feet to see if they are becoming numb.
- Examine the eyes with a unique lighted instrument, called an ophthalmoscope.
- Check blood pressure at least annually, which should be 130/80 mm/Hg or below.
- Have hemoglobin A1c test (HbA1c) completed bi-yearly, if diabetes is well-controlled, or otherwise every three months.
- Have cholesterol and triglyceride levels checked annually; a desirable level for LDL cholesterol levels is below 70-100 mg/dL.
- Have yearly tests to examine kidney function, which include micro-albuminuria and serum creatinine.
- Have eyes checked at least annually for signs of diabetic eye disease.
- Visit a dentist bi-yearly, for a thorough dental exam and cleaning.
Type 2 Diabetes screening is recommended for:
- Children, starting at age 10, who are overweight and have risk factors for developing Diabetes
- Overweight adults with risk factors
- Adults over 45 years of age
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Type 2 Diabetes?
After several years, Diabetes can lead to serious complications, such as:
- Eye problems, which include lessened eyesight, particularly at night, and sensitivity to light. Diabetic retinopathy, a condition in which blood vessels of the retina are damaged, is caused by Type 2 Diabetes. This condition could potentially cause blindness. Type 2 Diabetes also increases the risk for other vision disorders, such as cataract and glaucoma.
- Nerve damage, also known as neuropathy, is a common complication with Type 2 Diabetes. Excess sugar builds up in the blood vessels causing pain, tingling, and loss of feeling to the affected limbs.
- Nerve damage in the feet increases the risk of certain food complications. Feet and skin can acquire sores and infections, causing pain and itching. In severe cases, the foot or leg may need to be removed.
- Nerve damage can cause weakness or problems with urination. It may also make it more difficult for men to have an erection.
- Diabetes makes it difficult for one to control their blood pressure and cholesterol, leading to possible heart attacks, stroke, and other complications.
- Diabetes may cause one’s bone mineral density to lower, increasing the risk for developing osteoporosis.
- Alzheimer’s disease can be caused by Type 2 Diabetes.
- Elevated blood sugar has the potential to lead to kidney damage, also known as nephropathy. It can damage the filtering system of the kidneys, leading to kidney failure or kidney disease.
- Infections of skin, female genital tract, and urinary tract are more common.
- When an individual has Diabetes, their risk of heart attack is equivalent to an individual who has already experienced a heart attack. Both women and men with Diabetes are at equal risk.
How is Type 2 Diabetes Treated?
The objective of the treatment is to first lower high blood glucose levels. The long-term objective of treatment is to prevent medical problems associated with Diabetes. The management measures include:
- The principal treatment for Type 2 Diabetes is diet and exercise.
- It is recommended that after diagnosis, an individual should have a check-up each week, until a steady control of blood sugar is established. Physicians routinely suggest home blood sugar monitoring and urine testing.
Any individual with Type 2 Diabetes should be aware of the following ways to help manage their diabetic condition:
- How to identify and treat low blood sugar (or hypoglycemia)
- How to identify and treat high blood sugar (or hyperglycemia)
- Meal planning for diabetes
- Insulin administration
- How to take medications, if necessary
- How to alter amounts of insulin through food and exercises
- How to deal with sick days
- Where to purchase diabetes (medical) equipment and their proper storage and handling
Drugs may be prescribed to lower blood sugar levels, if they are not maintained at near-normal levels. These drugs help lower blood sugar levels in different ways;therefore, physicians may prescribe more than one.
Some medications, taken orally or intravenously, include:
- Alpha-glucosidase inhibitors (acarbose)
- Biguanides (metformin)
- Injectable medicines (comprising of exenatide, mitiglinide, pramlintide, sitagliptin, and saxagliptin
- Meglitinides (including repaglinide and nateglinide)
- Sulfonylureas (like glimepiride, glyburide, and tolazamide)
- Thiazolidinediones (including rosiglitazone and pioglitazone)
These drugs may be administered in conjunction with insulin, or insulin may be used solely on its own.
Diet and exercise:
- Consult a physician on how much fat, protein, and carbohydrates, are necessary in the diet
- Managing weight and eating healthy are vital for individuals with Type 2 Diabetes.
- Severely overweight patients whose diabetes is undermanaged may consider bariatric (weight-loss) surgery, such as gastric bypass surgery and laparoscopic gastric banding.
- Constant and consistent exercising is recommended to control blood sugar, as well as burn extra calories and fat, in order to maintain a healthy weight. When the heart beats faster during exercise, individuals will breathe faster, further lowering the blood sugar level, without requiring the use of medication.
- Exercise can be advantageous for health by improving blood flow and blood pressure. It also has the ability to increase the body’s energy levels, decrease tension, and improve stress handling abilities.
Blood sugar management:
- Monitoring blood sugar levels at home and keeping a record of the results is indicative of how an individual is managing Type 2 Diabetes. A physician will provide information on how frequently one should check their blood glucose levels.
- A glucometer device can be used to read blood sugar levels. In most cases, a small droplet of blood is produced by pricking ones finger with a small needle or lancet, which is then placed on a test strip, which is transferred to the device. Most results are recorded in 30-45 seconds.
Physicians recommend keeping a record of blood sugar levels. A target goal for blood sugar levels should be set at different times throughout the day. A plan should be set in place for what to do when blood sugar exceeds, or drops below normal levels:
- Individuals with Type 2 Diabetes should check their blood sugar once or twice a day.
- If blood sugar levels are under control, it may be necessary to only check a few times a week.
- One may test themselves when they wake up, before meals, and at bedtime.
- More frequent testing may be needed if individuals are sick or under stress.
Diabetes damages the nerves and blood vessels, making it difficult to feel pressure on ones feet. Often, a foot injury may go unnoticed, until a severe infection sets in.Type 2 Diabetes decreases the body’s ability to fight off infection. Small infections can worsen and cause the death of skin, and other tissues.
In order to prevent problems of the feet, one should:
- Stop smoking.
- Improve regulation of blood sugar.
- Get bi-yearly foot exams.
- Check feet each day, especially if there is a known episode of nerve or blood vessel damage.
- Wear proper shoes.
Weight-loss surgery: Increasingly, weight-loss surgery has been used as a tool to manage Type 2 Diabetes.
- Bariatric surgery is a weight-loss surgery that has been shown to improve Type 2 diabetic condition
- Weight loss surgery is effective in two ways: It restricts the amount of food the stomach can take in, and it decreases the absorption of food in the intestines.
- The two types of surgery available are gastric banding and gastric bypass. Gastric banding is a procedure in which an adjustable band is placed around the upper stomach to form a small pouch in the upper stomach. This band controls how quickly food can pass through. Gastric bypass restricts stomach volume and decreases calorie absorption. During this procedure, a portion of the stomach is surgically removed.
How can Type 2 Diabetes be Prevented?
- Type 2 Diabetes can be prevented by maintaining a healthy body weight and by having an active lifestyle
- Even if an individual has a family history of Diabetes, he or she can help prevent the condition by exercising regularly and eating healthy foods. Foods should be low in fat and calories, with an emphasis on fruits, vegetables, and whole grains. One should aim to exercise for about 30 minutes a day
- If an individual is overweight, losing between 5-10% of the body weight can help reduce the risk of developing Diabetes
What is the Prognosis of Type 2 Diabetes? (Outcomes/Resolutions)
- The outcome for patients with Diabetes varies from one individual to another and is dependent upon many factors and health issues
- After several years, Type 2 Diabetes can lead to complications with eyes, kidneys, nerves, heart, blood vessels, and other areas in the body
- When blood sugar and blood pressure is properly maintained, one can reduce the risk of death, stroke, heart failure, and other problems associated with Diabetes
- Some individuals with Type 2 Diabetes no longer need medication, if they lose weight and maintain a higher (physical) activity level. When an ideal weight is reached, the body’s own insulin and the diet consumed have the ability to maintain optimal blood sugar levels
Additional and Relevant Useful Information for Type 2 Diabetes:
There are voluntary organizations and support groups for Type 2 Diabetes that provides counsel, help, and understanding, to the affected individuals.
What are some Useful Resources for Additional Information?
American Diabetes Association
1701 North Beauregard Street, Alexandria, VA 22311
Phone: 1 (800) 342-2383
National Diabetes Education Program (NDEP)
1 Diabetes Way Bethesda, MD 20814–9692
Phone: 1 (888) 693–6337
TTY: 1 (866) 569–1162
Fax: (703) 738–4929
National Institute of Diabetes and Digestive and Kidney Disorders (NIDDK)
Office of Communications and Public Liaison Building 31
Room 9A04 Center Drive, MSC 2560
Phone: (301) 496-3583
Fax: (410) 689-3998
References and Information Sources used for the Article:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001356/ (accessed on 04/06/2013)
http://www.mayoclinic.com/health/type-2-diabetes/DS00585/DSECTION=prevention (accessed on 04/06/2013)
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