Diabetes Type 2 Part I

Diabetes mellitus type 2 or Type 2 Diabetes is a metabolic disorder that is usually characterized by insulin resistance, relative insulin deficiency and hyperglycemia and weight gain.


Let's clarify our terms before we go any further. When you eat any sweets ( candies, sodas, juices ) or any starches ( anything that contains grains such as bread, rice, potatoes,pasta, pastries, cookies and crakers ) or even fruits and some veggies, what you are actually eating is a carbohydrate that will break down in the end to a sugar called glucose. Glucose gets absorbed to your blood. Part of the glucose load can get easily to inside your cells ( cells need glucose to make energy ), but most of it cannot get inside. It needs a hormone made by your pancreas called insulin, which binds to cell receptos "telling " the receptors to "make it easy" for the glucose to come into the cell. On a normal person, pancreas makes sufficient insulin so that glucose can get efficiently inside the cell. When people gain weight, becoming obese, they become insulin resistant. This means that with the same amount of insulin, they cannot make sufficient glucose to go into the cells. At some point, the pancreas beggins to make more insulin to "make up" for this resistance... the problem then is temporarily solved as the same amount of glucose goes into the cell... except you need more and more insulin for your body to be able to do it... so the problem grows bigger and bigger and you grow more and more resistant to insulin.

Video that illustrates the normal role of insulin




Diabetes Mellitus type 2 is often managed by engaging in exercise and modifying one's diet ( excersice will make the glucose to go into the muscles with ease, modifying diet means eating less carbohydrates, so less glucose, thus reducing the insulin amount required, and decreasing insulin resistance ). It is rapidly increasing in the developed world, and there is some evidence that this pattern will be followed in much of the rest of the world in coming years. The CDC has characterized the increase as an epidemic in the USA. In addition, whereas this disease used to be seen primarily in adults over age 40 it is now increasingly seen in children and adolescents, an increase thought to be linked to rising rates of obesity in this age group.


Pathophysiology

Insulin resistance means that body cells do not respond appropriately when insulin is present.

Other important contributing factors are the following:

Increased hepatic glucose production (e.g., from glycogen degradation), especially at inappropriate times ... How come? Well, when glucose cannot get into the cells due to resistance to insulin, cells start starving... they make chemicals that travel to the liver and tell the liver that it needs to make more glucose ( the cells do not sense that outside, in the blood, they have got a lot of glucose... for them there is none ). t his certainly worsens the problem.

Decreased insulin-mediated glucose transport in (primarily) muscle and adipose tissues (receptor and post-receptor defects)... meaning that glucose is unable to get into muscles and fat.

Impaired beta-cell function—loss of early phase of insulin release. This is due to the massive amounts of glucose that come into the body.

Video that shows what happens in diabetes. It however, neglects to mention that for years and years of poor eating, your insulin levels get impressively high before your pancreas stops making enough of it




Type 2 diabetes may go unnoticed for years in a patient before diagnosis, since the symptoms are typically milder and can be sporadic. However, severe complications can result from improperly managed Type 2 diabetes, including renal failure, blindness, wounds that are slow to heal (including surgical incision), and arterial disease ( may lead to limb amputation ), including coronary artery disease ( and heart attacks ). The onset of Type 2 is most common in middle age and later life, although is being more frequently seen in adolescents and young adults due to the increasing prevalence of obesity in these groups.

About 90–95% of all North American cases of diabetes are type 2, and about 20% of the population over the age of 65 has diabetes mellitus type 2. The fraction of type 2 diabetics in other parts of the world varies substantially, almost certainly for environmental and lifestyle reasons, though these are not known in detail. Diabetes affects over 150 million people worldwide and this number is expected to double by 2025. About 55 percent of type 2 are obese —chronic obesity leads to increased insulin resistance that can develop into diabetes, most likely because adipose tissue is a (recently identified) source of several chemical signals to other tissues (hormones and cytokines). Other research shows that type 2 diabetes causes obesity.

Diabetes mellitus type 2 is often associated with obesity, hypertension, elevated cholesterol (combined hyperlipidemia), and with the condition often termed Metabolic syndrome (it is also known as Syndrome X, Reavan's syndrome, or CHAOS). Additional factors found to increase risk of type 2 diabetes include again, high-fat diets and a less active lifestyle.


Symptoms of Diabetes



Are polyuria ( increased urination ), polydypsia ( increased thirst ) and polyphagia ( increased appetite ), plus at times others such as blurred vision, fatigue. the real danger, however is that some times, when the blood glucose values increase slowly, the disease may present with no symptoms.







Diagnosis

The World Health Organization definition of diabetes is for a single raised glucose reading with symptoms, otherwise raised values on two occasions, of either:

Fasting plasma glucose ≥ 126 mg/dl
or
With a Glucose tolerance test, two hours after the oral dose a plasma glucose ≥ 200 mg/dl


Screening and prevention

Interest has arisen in preventing diabetes due to research on the benefits of treating patients before overt diabetes. The U.S. Preventive Services Task Force (USPSTF) USPSTF does recommend screening for diabetics in adults with hypertension or hyperlipidemia (grade B recommendation).

In 2005, an evidence report by the Agency for Healthcare Research and Quality concluded that "there is evidence that combined diet and exercise, as well as drug therapy (metformin, acarbose), may be effective at preventing progression to DM in IGT subjects".


Accuracy of tests for early detection

If a 2-hour postload glucose level of at least ≥ 200 mg/dL is used as the reference standard, the fasting plasma glucose >126 mg/dL diagnoses current diabetes with:

sensitivity about 50%
specificity greater than 95%