People who have diabetes often have short-term or long-term complications.
Short term complications include:
- Hypoglycaemia: low blood glucose levels – where medication and insulin injections aren’t balanced with food and activity. ‘Hypos’ can occur without warning and symptoms include feeling shaky, sweaty, hungry, tired, having blurred vision, problems concentrating, headaches, and feeling tearful. They can often be avoided by eating the right types of foods regularly and can be treated by having a sugary drink, glucose tablets or sweets
- Hyperglycaemia happens when medication and insulin injections aren’t correctly balanced with food and activity. Causes include missing out on a dose of insulin, or eating too much carbohydrate but it can also be as a result of stress or infection. Symptoms include urinating more often than normal, feeling thirsty, having a headache and feeling tired. They can be treated by taking extra insulin but you should always seek medical advice
- Diabetic ketoacidosis (DKA) is a life-threatening emergency that’s more common with Type 1 diabetes. It’s caused by a lack of insulin that stops the body being able to use glucose for energy; the body then starts to break down tissue to use for energy. A by-product of this process is ‘ketones’, poisonous chemicals which can build up and lead to the blood becoming acidic
DKA can often happen around the time that Type 1 diabetes is first diagnosed, and can also occur during an illness, at puberty, or if an insulin injection has been missed. It rapidly becomes worse over 24 hours, and it’s essential to get to hospital as fast as possible
- Hyperosmolar hyperglycaemic state (HHS) can be a life-threatening emergency affecting people who have Type 2 diabetes when they have high blood glucose levels. It can become worse over several weeks because of a combination of infection and becoming dehydrated. It can be caused by stopping medication during illness (for example, because of nausea or difficulty swallowing); or the illness itself can cause hormones to become unbalanced and glucose to rise in the bloodstream. Symptoms include frequent urination, feeling thirsty and/or sick, feeling disorientated and, if not treated, becoming unconscious
Long term complications include:
- Eye problems (retinopathy): this is damage to the retina and can lead to blindness. It’s caused by blockages in the blood vessels supplying the retina which can damage it and stop it working. Having high glucose levels in the blood can cause retinopathy and if you smoke, this can increase your risk.
- Heart problems (cardiovascular disease)
People with diabetes are more likely to develop cardiovascular disease – heart disease, stroke and other diseases of the heart and circulation. This is because blood vessels can be damaged by high blood glucose levels, as well as high blood pressure, smoking or high cholesterol levels. It’s very important for people who have diabetes to have a healthy diet, take regular exercise and reduce weight if necessary, as well as stopping smoking.
Heart problems include:
Macrovascular disease: damage to the arteries and veins that transport blood away from the heart. This includes damage to the tiny vessels (capillaries) where oxygen and carbon dioxide are exchanged.
Arteriosclerosis or atherosclerosis: when cholesterol and other fatty substances build up on the walls of blood vessels (this is known as plaque) they can narrow the arteries, restricting blood flow.
In some cases, the plaque can tear the artery walls and blood cells (platelets) attempt to repair any damage. However, this causes blood clots to form. As time goes on, blood vessel walls lose flexibility, which can be a factor in high blood pressure (hypertension), which further damages the blood vessels.
If the blood clot breaks away from the artery, it can travel until it reaches a narrow section which can become blocked, starving part of the body of oxygen; depending on which organ is served by the blocked artery, this can result in heart attack, stroke or peripheral vascular disease (PVD) which can cause pain and, in some cases, lead to the need for amputation of a limb.
- Kidney disease (nephropathy)
People with diabetes are more likely to have kidney disease – it affects around one in three people with diabetes – especially if they also have high blood pressure (hypertension).
As well as regulating the amount of fluid and salts and helping to control blood pressure, the kidneys also release hormones. Kidney disease of diabetes is caused by damage to the kidneys’ small blood vessels. It’s important for people with diabetes to regulate blood glucose levels to reduce this risk, as well as keeping blood pressure under control.
Kidney disease can develop slowly and is more likely if you’ve had diabetes for many years.
Your doctor will check your urine regularly for a protein known as ‘albumin’ which appears during the early stages of kidney disease. If it’s diagnosed early, kidney disease can be effectively managed.
- Nerve damage (neuropathy)
Nerves are responsible for carrying messages between the brain and other parts of the body. This allows us to see, hear, feel and move. As well as these signals, nerves also carry messages to the heart (affecting its rhythm) and the lungs. Damage to nerves can cause problems in many parts of the body. High blood glucose levels can damage tiny blood vessels supplying the nerves, stopping nutrients getting to the nerves and resulting in damage to them. There are three types of neuropathy:
This affects the sensations of touch, temperature, pain and other feelings. Although it can affect the arms and hands, it mainly affects the feet and legs, with symptoms including: tingling, numbness, inability to feel pain or temperature, burning or shooting pains and, in some cases, loss of coordination. If you lose feeling in your feet, this can be especially dangerous because you might not notice injuries caused, for example, by sharp objects, burns, or ill-fitting shoes. Charcot foot is when the structure of the foot collapses due to a combination of neuropathy and inflammation.
This affects the nerves carrying information to body organs and glands, which control functions that we don’t normally think about such as digestion, bowel control, heart beat and the function of sexual organs. Nerve damage can lead to digestive problems, incontinence, irregular heart beat (arrhythmia), problems with sweating and impotence (the inability to have or maintain an erection).
This affects the ability to move and can cause weakness and muscle wasting, as well as muscle twitching and cramps. The muscle weakness can, in turn, lead to falls or problems carrying out everyday tasks such as doing up buttons.