Type 1 diabetes

Type 1 diabetes, also called diabetes mellitus type 1, is an autoimmune disease that results in high blood sugar. This is because the body cannot create enough of the hormone insulin. People with type 1 diabetes need to take insulin injections to stay healthy. If they do not get enough insulin, they can become very sick or even die. People with type 1 diabetes have an higher risk of developing neuropathy (nerve pain), kidney disease, retinopathy (which affects sight), depression as well as diseases involving blood vessels such as stroke, heart disease or gangrene. 

There are many types of diabetes, about 5-10% of people with diabetes have type 1.

 Cause 
Type 1 diabetes is a condition caused by a lack of insulin in the body. Insulin is a hormone produced by cells in the pancreas. Insulin is responsible for moving sugars out of the blood and into cells to be used by the body for energy. If insulin is not made, the body will search for other ways to get the sugars needed to feed the body's cells, including breaking down muscle and fat, leading to a loss of weight and the producion of ketones, which can cause ketoacidosis (see below).Type 1 Diabetes, NHS Choices, http://www.nhs.uk/Conditions/Diabetes-type1/pages/introduction.aspx . Accessed 09/11/2015

Insulin not produced in the pancreas due to an autoimmune condition attacking its cells. The body's immune system attacks the cells responsible for producing insulin in the pancreas, the beta cells. The beta cells are damaged in a way that prevents them from producing more insulin. As more and more of these cells are damaged, less insulin is produced in the body. This means that more sugar remains in the bloodstream rather than being moved into cells. This high blood sugar causes the symptoms seen in type 1 diabetes.Daneman D (2006). Type 1 diabetes. The Lancet 367(9513): 847-858 http://www.sciencedirect.com/science/article/pii/S0140673606683414

The disease is thought to be strongly linked to genetic factors, but the trigger that starts the autoimmune disease is not currently known.

 Epidemiology 
In the past, type 1 diabetes was generally thought to be a disorder in children and teenagers. However, it's now been found that adults can be diagnosed with the disease.Atkinson MA et al. Type 1 Diabetes. The Lancet 2014; 383(9911): 69-82

Although type 1 diabetes can now be diagnosed at any age, it is one of the most common chronic conditions in children and young adults. Being diagnosed at ages 5–7 or at the start of puberty is particularly common.Harjutsalo V, Sjoberg L, Tuomilehto J. Time trends in the incidence of type 1 diabetes in Finnish children: a cohort study. Lancet 2008 ;371: 1777–82 Type 1 diabetes is also slightly more common in boys.

Cases of type 1 diabetes have been increasing across the world for several decades. Approximately 1 in 300 people are diagnosed with type 1 diabetes by the age of 18 in the United States.Maahs DM et al. Chapter 1: Epidemiology of Type 1 Diabetes. Endocrinol Metab Clin North Am 2010; 39(3): 481-497

 Symptoms 
In type 1 diabetes, symptoms generally develop over a few days or weeks, though may take longer in adults. The main symptoms are:Type 1 Diabetes - Symptoms, NHS Choices, http://www.nhs.uk/Conditions/Diabetes-type1/Pages/Symptoms.aspx . Accessed 09/11/2015
 Feeling very thirsty
 Urinating more often than normal
 Exhaustion
 Loss of weight
 Bedwetting (especially in children)
 Blurring of sight
 Slow healing of wounds and grazes

Nausea, vomiting and heavy breathing are more serious symptoms that occur at a later stage in the disease.

 Complications 
People with type 1 diabetes may have to deal with both short-term and long-term complications, particularly if the disease is not well managed.

 Short-term complications 

 Hypoglycaemia 
Hypoglycaemia is when blood sugar levels decrease to below normal. This is most commonly due to overuse of medications for diabetes type 1 like insulin, poor diet control, and rigorous exercise. The risk of suffering from low blood sugar is increased by drinking alcohol.Hypoglycemia. National Institute of Diabetes and Digestive and Kidney Diseases. October 2008. http://www.niddk.nih.gov/health-information/health-topics/Diabetes/hypoglycemia/Pages/index.aspx .  Retrieved 9 November 2015 This may lead to various other symptoms, including confusion, loss of consciousness, clumsiness, seizures or death.

 Diabetic ketoacidosis 
Diabetic ketoacidosis (DKA) is a very serious complication of type 1 diabetes. It is a medical emergency and requires rapid medical attention to prevent further damage to a patient, if left untreated it can potentially lead to death. DKA occurs when there is not enough insulin in the body to supply sugars to the body's cells. In order to give its cells enough energy to survive, the body begins to produce acidic ketone bodies which are then used to feed energy to the cells.Diabetes Complications - Diabetic Ketoacidosis, Diabetes UK, http://www.diabetes.co.uk/diabetes-complications/diabetic-ketoacidosis.html. Accessed 09/11/2015

If too many ketone bodies build up the blood becomes acidic, damaging the body and leading to the symptoms:
 Vomiting
 Dehydration
 Difficult breathing
 Fast heartbeat
 Confusion
 Coma

Treatment induced neuropathy in diabetes (TIND)

Another short-term complication is treatment induced neuropathy in diabetes (TIND). This leads to painful nerve pain and retinopathy, both of which persist for a few months to years. The cause is known to be a sudden drop in HbA1c, at least 3 percentage points within 3 months. This means that slowly reducing high long term blood sugar values (measured by HbA1c) is important.

 Long-term complications 

If diabetes is not treated, even mildly raised blood sugar levels can damage nerves, organs and blood vessels in the body.

 Small blood vessel complicationsDiabetes Type 1 - Complications, NHS Choices, http://www.nhs.uk/conditions/Diabetes-type1/Pages/Complications.aspx . Accessed 09/11/2015 
 Diabetic retinopathy, damage to the blood vessels prevent enough blood from reaching the eye. This can lead the eye's retina being damaged, resulting in loss of vision or blindness.
 Diabetic neuropathy, damage to blood vessels near nerves can result in reduced blood flow. This can damage the nerves, leading to a loss in the sense of touch, normally starting from the hands or feet, before spreading up the body.
 Diabetic nephropathy, blood vessels in the kidney become damaged, making the kidney work less effectively. In severe cases. this can result in kidney failure.
 Sexual dysfunction

 Large blood vessel complicationsFowler MJ. Microvascular and Macrovascular Complications of Diabetes. Clinical Diabetes 2008; 26(2): 77-82 
 Increased risk of heart disease and stroke
 Narrowing of blood vessels (peripheral arterial disease).
 Diabetic foot, narrowing of blood vessels reduces sensitivity and slows wound healing in the foot. If not managed appropriately, can lead to ulceration and gangrene in the foot. In very severe cases, amputation may be required.

 Management 
There is no known cure for diabetes. Instead, treatment is designed to help keep blood sugar levels normal in order to reduce the chances of complications developing as the disease progresses. There are two main method that are combined to manage diabetes type 1:

 LifestyleDiabetes Type 1 - Living With, NHS Choices, http://www.nhs.uk/Conditions/Diabetes-type1/Pages/living-with.aspx . Accessed 09/11/2015 
 Healthy eating: eating a diet focused on fruit and vegetables, whilst limiting fats salt and sugar helps keep blood sugar levels in check.
 Exercise: regular physical activity helps to lower your blood sugar level. A good goal to aim for is 150 minutes of exercise a week.
 Stopping smoking: smoking further increases the risk of heart disease, peripheral arterial disease and stroke. Stopping or reducing smoking will reduce the risk of these complications.
 Reducing alcohol: alcohol can either raise or lower blood sugar, and makes it difficult to monitor your own blood sugar levels. Drinking less alcohol can reduce these risks.

 Insulin injections 
Type 1 diabetes occurs due to the bodies inability to produce its own insulin. To counter this, insulin can be injected into the blood manually. When diabetes is first diagnosed, a plan should be made for insulin treatment in order to not under or overdose, which can lead to serious complications. A diabetic should monitor their own blood sugar levels continuously to know whether they need a dose of insulin to lower their blood sugar.Diabetes Type 1 - Treatment, NhS Choices, http://www.nhs.uk/Conditions/Diabetes-type1/Pages/Treatment.aspx . Accessed 09/11/2015

There are different kinds of insulin that can be taken:Patient Information: Diabetes mellitus type 1: Insulin treatment (Beyond the Basics), UpToDate, http://www.uptodate.com/contents/diabetes-mellitus-type-1-insulin-treatment-beyond-the-basics. Accessed 09/11/2015 
 Rapid-acting insulin and short-acting insulin get insulin into the bloodstream very quickly. They are typically taken before a meal to prepare for the rise in blood sugar that follows eating food.
 Long acting insulin provides insulin in the system for up to 24 hours. It is generally taken once a day

 References 

Category:Diabetes mellitus
Category:Autoimmune diseases