Type 2 Diabetes
Type 2 diabetes is the most common form of diabetes, accounting for 90 – 95% of cases. Type 2 diabetes was formerly known as non-insulin-dependent or adult-onset diabetes due to its occurrence mainly in people over 40. In type 2 diabetes, the body does not respond properly to insulin, this is known as insulin resistance. There are three stages in the progress of this condition:
The first stage in type 2 diabetes is when resistance to insulin develops. Normally insulin attaches to receptors on liver and muscle cells and facilitates the movement of blood sugar into the cells. In type 2 certain mechanisms prevent insulin from moving blood sugar into these cells. Most patients with type 2 diabetes produce variable, even normal or high, amounts of insulin. In the beginning, this amount is usually enough to overcome such resistance.
Owing to the progression of the disease, over time, the pancreas becomes unable to produce enough insulin to overcome resistance. In type 2 , the initial effect of this stage is usually an abnormal rise in blood sugar after a meal (called postprandial hyperglycaemia).
Eventually, the cycle of elevated glucose further damages beta cells, thereby drastically reducing insulin production and causing full-blown diabetes. This is made evident by fasting hyperglycaemia, in which glucose levels are high most of the time. Type 2 diabetes occurs when the body doesn’t produce enough insulin to function properly, or the body’s cells don’t react to insulin. This means that glucose stays in the blood and isn’t used as fuel for energy. Type 2 diabetes mellitus is a metabolic disorder that results in hyperglycemia (high blood glucose levels)
Type 2 diabetes therefore develops due to the body:
- Being ineffective at using the insulin it has produced; also known as insulin resistance and/or
- Being unable to produce enough insulin
Risk factors for type 2 diabetes
Five of the main risk factors for developing the condition are:
The risk of developing type 2 diabetes increases with age. This may be because people tend to gain weight and exercise less as they get older. Maintaining a healthy weight by eating a healthy, balanced diet and exercising regularly are ways of preventing and managing diabetes. Caucasians over the age of 40 have an increased risk of developing type 2. People of South Asian, Chinese, African-Caribbean and black African descent have an increased risk of developing type 2 diabetes at a much earlier age. Despite increasing age being a risk factor for type 2 diabetes, over recent years younger people from all ethnic groups have been developing the condition. It’s also becoming more common for children, in some cases as young as seven, to develop type 2 diabetes.
Genetics is one of the main risk factors for type 2 diabetes. The risk of developing the condition is increased if you have a close relative – such as a parent, brother or sister – who has the condition. The closer the relative, the greater the risk. A child who has a parent with type 2 diabetes has about a one in three chance of also developing it.
Being overweight or obese
You’re more likely to develop type 2 diabetes if you’re overweight or obese (with a body mass index (BMI) of 30 or more). In particular, fat around your tummy (abdomen) increases your risk. This is because it releases chemicals that can upset the body’s cardiovascular and metabolic systems. This increases your risk of developing a number of serious conditions, including coronary heart disease, stroke and some types of cancer. Measuring your waist is a quick way of assessing your diabetes risk. This is a measure of abdominal obesity, which is a particularly high-risk form of obesity. Women have a higher risk of developing type 2 diabetes if their waist measures 80cm (31.5 inches) or more. Asian men with a waist size of 89cm (35 inches) or over have a higher risk, as do white or black men with a waist size of 94cm (37 inches) or over. Use the BMI calculator to find out if you’re a healthy weight for your height. Exercising regularly and reducing your body weight by about 5% could reduce your risk of getting diabetes by more than 50%.
People of south Asian, Chinese, African-Caribbean and black African are more likely to develop type 2 diabetes. Type 2 diabetes is up to six times more common in south Asian communities than in the general UK population, and it’s three times more common among people of African and African-Caribbean origin. People of south Asian and African-Caribbean origin also have an increased risk of developing complications of diabetes, such as heart disease, at a younger age than the rest of the population.
The risk of developing type 2 diabetes is also increased if your blood glucose level is higher than normal, but not yet high enough to be diagnosed with diabetes. This is sometimes called “pre-diabetes” – doctors sometimes call it impaired fasting glycaemia (IFG) or impaired glucose tolerance (IGT). Pre-diabetes can progress to type 2 diabetes if you don’t take preventative steps, such as making lifestyle changes. These include eating healthily, losing weight (if you’re overweight) and taking plenty of regular exercise.
Women who have had gestational diabetes during pregnancy also have a greater risk of developing diabetes in later life.
People with other health conditions may also be at increased risk. This includes people with cardiovascular disease (those who have had myocardial infarction or a stroke) or polycystic ovary syndrome or have a history of gestational diabetes.
People with mental health conditions or learning disabilities also appear to be at greater risk.
People taking certain medication such as steroids, anti-retrovirals and some antipsychotic drug
The main symptoms of type 2 diabetes, are:
1. Urinating more often than usual, particularly at night
2. Feeling very thirsty
3. Feeling very tired
4. Unexplained weight loss
5. Itching around the penis or vagina, or frequent episodes of thrush
6. Velvety dark skin changes of the neck, armpit and groin, called Acanthosis Nigricans
7. Numbness and tingling of the hands and feet
8. Sexual dysfunction, such as erectile dysfunction in men.
9. Slow-healing sores or cuts
10. Blurred vision
The signs and symptoms of type 1 diabetes are usually obvious and develop very quickly, often over a few weeks. The signs and symptoms of type 2 diabetes aren’t always as obvious, and it’s often diagnosed during a routine check-up. This is because the symptoms are often mild and develop gradually over a number of years.
This means that you may have type 2 diabetes for many years without realising it.
Complications of Type 2 diabetes
The complications of Type 2 diabetes can be grouped as Macrovascular or Microvascular.
People who have type 2 diabetes are at greater risk of developing cardiovascular diseases such as heart attack, stroke or problems with circulation in their legs and feet (peripheral artery disease). These are the “macrovascular” complications of diabetes. “Macrovascular” means that these complications affect the larger blood vessels. This risk is especially high in people who also have high blood pressure.
If there is too much sugar in the blood for years at a time, the smaller blood vessels in the eyes, nerves and kidneys can be damaged. These are called the microvascular complications of diabetes. “Microvascular” means that the smaller blood vessels are affected. The medical names for these kinds of complications are retinopathy (damage to the retina), neuropathy (nerve damage), and nephropathy (kidney damage). The later someone develops type 2 diabetes, the less likely it is that they will develop these kinds of problemsHowever, type 2 diabetes is now becoming more common in young adults, teens and children and accounts for roughly 90% of all diabetes cases worldwide.