This blog will provide general advice about type two diabetes. There is another blog on my website describing how we manage diabetic patients in the perioperative period.
There are two types of diabetes: type I occurs when the insulin producing cells in the pancreas are destroyed. The reason is unknown although viral infections and abnormalities of the immune system have been implicated. Type I diabetes tends to occur early in life. Type II diabetes is also called maturity onset diabetes. Insulin is still produced by the pancreas; indeed in the early stages the pancreas produces more insulin than normal but the body becomes resistant. The pancreas then becomes exhausted and is unable to provide adequate insulin so the blood sugar rises.
Genetics plays a significant part in type II diabetes as does age, diabetes during pregnancy and polycystic ovary syndrome. However most type II diabetes is related to lifestyle choices such as diet and lack of exercise as well as obesity. Type II diabetics have an increased risk of heart disease, kidney disease, eye problems and problems with the peripheral circulation. They can develop nerve problems including problems with the gastrointestinal tract, depression and dementia.
Diabetes is often first detected by finding sugar in the urine. A fingerprint test will give a quick measurement of the current blood sugar but the definitive test is haemoglobin A1c (HbA1c). Historically we have regarded someone as diabetic when their blood sugar is over 5.4 to 5.6 (depending on the machine) and the HbA1c is over 48mmol/mol or 6.8%. However, it is dangerous to consider these numbers are strict cut-off points and in practice both the blood sugar and the HbA1c will rise over time so that we can consider patients with ‘high normal’ readings as prediabetic who will eventually become diabetic without intervention.
Prevention of type 2 diabetes is about controlling weight, maintaining a healthy diet and exercise. Choosing your parents to reduce genetic risk would be marvelous but is impractical! In terms of diet it is carbohydrate and not sugar which is the culprit. Refined carbohydrates found in white bread, potatoes, pasta and rice are called glycaemic and require large amounts of insulin to be metabolised. Carbohydrates found in wholemeal bread, sweet potatoes, and brown rice are absorbed more slowly and do not produce this problem. Roughage in terms of green vegetables and grains also appears to reduce the risk.
Exercise has a direct effect on reducing diabetes and there appears to be no top limit. Sadly in my opinion this has led to quite daft recommendations which are unachievable for many people living a busy life. In practical terms exercise which increases your heart rate and/or makes you sweat for 20 minutes twice a week provides a significant benefit.
The good news is that prediabetes can be reversed and even some patients with diabetes itself can reverse the problem by losing weight, eating healthily and increasing the amount of exercise they take. For those patients who remained diabetic the treatment is normally tablets. Historically we have tended to avoid medication where possible but metformin, the commonest drug used for type II diabetes, may well dramatically reduce heart disease as well as cancer and even dementia so there is an argument for its early introduction. There is more about metformin on my blog about prophylactic drugs.