If it gets complicated

Avoiding complications

The first thing that you need to know is that you will not inevitably develop complications simply because you have diabetes. Careful research has shown that, the better your blood glucose control, the less likely you are to experience any complications.
Large studies in the USA (the Diabetes Control and Complications Trial or DCCT) and the UK (UK Prospective Diabetes Study or UKPDS) have shown that any improvement in blood glucose control will reduce your risk of developing complications.
Knowing this motivates many people to work harder at controlling their diabetes when they’re tempted to let things slide a little.

Stop smoking

Along with good diabetic control, giving up (or not starting) smoking can reduce your chances of developing complications. Smoking and diabetes definitely don’t mix. All of the possible complications discussed below are more common in people who smoke, and anyone who has already developed any of them should stop smoking immediately. The importance of this can’t be overstressed, and knowing that may be the incentive that you need to help you give up if you are a smoker.

Your eyes

Diabetes can affect your eyes in various different ways.

Blurring

When you first start having insulin or tablet treatment, you may notice that your vision seems a bit blurred. This is because the lens in your eye becomes dehydrated when diabetes develops and, by rapidly lowering your blood glucose, the treatment brings about a fluid shift into your eye. This is what causes any blurring.
Fortunately, the problem is only temporary and should clear up in a few months without the need for treatment. If it happens to you, wait until the blurring has disappeared before getting a prescription for new spectacles if you need one. The result of your sight test may well be different once your diabetes has stabilised.

Cataracts

When you have had diabetes for a long time, you are more susceptible to cataracts because of a build-up of sugars in the lens of the eye. These make the lens of your eye opaque, interfering with the transmission of light to the back of your eye, and can be a particular nuisance in bright sunlight.
Fortunately, this problem can be treated quite easily with a simple operation to replace your damaged lens with a plastic one. It can often be done under a local anaesthetic, and you will normally be treated as a day patient. The results are generally excellent.

Retinopathy

Both types of diabetes can affect a highly specialised structure at the back of your eye called the retina. T

he central part (the macula) enables you to see colours and fine detail, whereas the outer (or peripheral) part picks up black and white and enables you to see in restricted light.
It’s the small blood vessels (called capillaries) supplying the retina that are affected by diabetes. This is probably because of a build-up of glucose and other sugars in the walls of the blood vessels, making them weaker.
Small blisters or microaneurysms can form and occasionally burst, resulting in tiny haemorrhages.
Sometimes, blood vessels may leak, allowing fluid to collect on the surface of the retina, which then forms what are called hard exudates. This leakiness is usually a sign that the blood supply to that part of the eye is not as good as it should be.
When retinopathy reaches an advanced stage, new blood vessels can grow as the eye tries to improve its blood supply. These new vessels are fragile and may
break and bleed extensively. This condition, known as a vitreous haemorrhage, can seriously affect sight.

Treating retinopathy

Fortunately, laser treatment can do a great deal to repair the damage caused by diabetic retinopathy. It’s normally directed at the peripheral part of the retina, well away from the macula, and can remove hard exudates and prevent new blood vessels from growing. The earlier the treatment is given, the more successful it is, which is why it is essential that you should have your eyes checked at least once a year. Eye checks can be done by an optician or optometrist, a specialist ophthalmologist or a doctor who is skilled at this type of examination. The National Service Framework (NSF) for Diabetes (see page 127) set a deadline for 2007 for an annual photographic eye check to be available for all people with diabetes in England and Wales (earlier for Scotland).

Maculopathy

Some people may develop a more serious form of retinopathy called maculopathy. This means that the blood supply to the central part of the eye is reduced, which can seriously affect the person’s ability to perceive colour and fine detail. Unfortunately, laser treatment is not so successful in treating this particular problem.

Laser treatment

If you need laser treatment, you will normally be asked to attend the outpatient clinic at a special eye unit.
First, drops are put into your eye to widen the pupil so that it’s easier to see the retina. You then rest your head in a special bracket to keep it still while the doctor uses a type of camera to examine your eye and identify which parts of the retina need treatment (see figure on page 14). The treatment itself is usually painless, but you’ll see brief flashes of bright light as the laser is used – sometimes several hundred in each treatment session.
You may need several of these sessions for each eye and, afterwards, your vision could be blurred for about 24 to 48 hours. Extensive laser treatment can reduce the width of vision or visual field and make it harder to see at night. Sometimes the reduction in visual field may have implications for driving.

Vitrectomy

Occasionally for advanced eye disease it is necessary to remove the vitreous humour and replace it with an oil-based liquid. This is called a vitrectomy and is only carried out in specialised vitreoretinal surgery units.

Others

There is intensive research into medical treatment of eye complications. Local injections of steroids into the macula can reduce swelling (oedema). Inhibitors of a growth factor called vascular endothelial growth factor (VEGF) may prevent new vessels from growing. These treatments are, however, still restricted to specialised units.

Your kidneys

One of the main tasks of the kidney is to excrete (get rid of) excess water and the natural chemical byproducts of everyday living via the urine. They do this by filtering the blood through a delicate network of very small vessels called capillaries (similar to those seen at the back of the eye).
As in the eye diabetes can damage these small blood vessels by an accumulation of glucose in the vessel walls. The effect is to allow chemicals and substances that would normally be retained in the blood to pass into the urine. It would be like making holes in a tea strainer larger, which would allow tea leaves to appear in the cup.
One of the substances that appears in the urine when the filters are damaged is protein, and a particular protein called albumin appears at a very early stage of diabetic kidney damage. Albumin in the urine is also called albuminuria and a test can detect the presence of very small amounts (microalbuminuria).
The availability of these tests is one reason why you will probably be asked to provide a urine sample at each of your diabetes clinic visits, even if you are normally performing blood tests for glucose. Sometimes you may get a positive result from the albumin test, which is in fact caused by a urinary infection. Your clinic will check your urine sample to exclude this.
Your doctor will want to keep a closer eye on you if albumin is detected in your urine because there is the possibility of more serious kidney damage and even kidney failure in the long term.
These check-ups are even more important if, like many people with albuminuria, you also have raised blood pressure. The two tend to go together because the kidneys also have a role in controlling blood pressure. Research has shown that careful control of blood pressure in people with diabetes reduces or even prevents kidney damage occurring.
At the moment, those people who developed kidney failure may need treatment either by dialysis (a kidney machine) or by transplantation, but there is a lot of current research into prevention of kidney damage that may one day make this unnecessary.

Your nerves

Diabetes can affect the nerves in two ways: as with the eyes and kidneys, their blood supply may be affected, or there can be direct damage to the nerves themselves as a result of high blood glucose.
Any kind of nerve damage is known medically as neuropathy. The consequences will depend on which of the three types of nerve is affected.

Motor (movement) nerves

These carry messages to the muscles from the brain, stimulating them to contract. Damage to this type of nerve is known as motor neuropathy and can lead to a loss of small muscle activity in the feet or hands. As a result, the toes can become clawed and stick upwards, and the fingers become weak. For more on diabetes and the foot, see page 119.

Sensory nerves

These detect pain, touch, heat and other sensations, and send messages back to the brain. Sensory neuropathy can make the feet very sensitive and even painful at first, but eventually they will become numb and unable to feel any kind of sensation, including pain.

Autonomic nerves

These are responsible for controlling automatic bodily functions such as bowel and bladder activity. Autonomic neuropathy is relatively uncommon, and its most troublesome effects are on the bladder and bowels.
It can result in constipation or diarrhoea that comes and goes, and occasionally the person may suffer from persistent vomiting. Men may also be troubled by a
reduction of their sexual potency. Most of these problems can be improved by drug treatment.

Male sexual potency

A man’s ability to have a normal erection depends upon a good supply of blood via the arteries leading to the penis, and also on an intact nerve supply. Blood enters the penis through the arteries, which are dilated (made wider) by nerve stimulation as a result of sexual arousal. The extra blood presses on the veins and is therefore trapped in the penis, leading to an erection. Diabetes can affect both the blood supply and the nervous control needed to maintain an erection.
It’s important to remember, however, that impotence can have psychological as well as physical causes, whether or not you have diabetes, so it’s very important to discuss any sexual problems openly and frankly with your medical advisers.
There are treatments available on prescription for sexual impotence (often called erectile dysfunction or ED) in men with diabetes. Please ask your diabetes care team for advice.

Your skin

A small minority of people with diabetes may have skin problems caused by damage to small blood vessels. When this occurs, it results in reddening and thinning of the skin over the lower shin bones – a condition known as necrobiosis lipoidica. Unfortunately, there is no effective treatment.

Your arteries

Diabetes leads to an increased risk of developing hardening and narrowing of the large blood vessels or arteries, which can lead to heart attacks and strokes, and poor circulation in the legs.
Both smoking and being overweight increase the risk still more, so it is really important that you stop smoking and try to lose weight. In any case, smoking is a known major risk factor for arterial disease even in people who don’t have diabetes.
Another factor that can cause arterial disease is a raised blood cholesterol level. Recent research has shown that lowering blood cholesterol with diet and/or medication can lower the risk of heart attacks and strokes.
High blood pressure can also cause hardening of your arteries. Lowering blood pressure has been shown to reduce the risk of heart attacks and strokes, as well as preventing kidney complications (see above).
Problems caused by hardening of the arteries are very common, and there are both medical and surgical treatments available. Narrowed portions of larger arteries can be bypassed by surgical operation, or widened by passing a balloon across them (angioplasty) or using an implanted metal stent. However, it is well worth doing everything that you can to prevent such problems developing in the first place.

Your feet

You need to be aware of changes to your feet that can arise because of your diabetes and what you can do to minimise the risk of damage. Most people with diabetes don’t get serious foot problems, but even those who do can prevent things getting worse by caring for their feet properly.
Healthy circulation to your feet will help to keep the tissues strong, and you can encourage this by eating the right kinds of foods, keeping good control of your diabetes and not smoking.
Ensure that your shoes fit well with enough room for your toes, and with a fastening to keep them in place without rubbing. In addition, there are specific things that you can do to look after your feet. These are designed to guard against four changes that can be caused by diabetes.
 

Poor blood supply to the foot

This results from narrowing of the blood vessels. When your circulation is restricted in this way, your foot is less able to cope with hazards such as cold weather, infection or injury, and is more susceptible to the other three changes
below. Keep your feet warm with good quality socks and stockings, but avoid overheating and be very careful of seams that can press and rub, causing blisters. Consider wearing socks inside out if the seams are prominent.

Caring for your feet

Good foot care is very important in preventing complications in diabetes and should form part of your hygiene routine. Feet should be washed and inspected daily.
• Wash your feet daily in warm water using a mild soap. Don’t soak them for a long time because it removes more of the precious oils from your skin. You may develop soggy areas between your toes which can split or increase the likelihood of soft corns

• Apply surgical spirit to any white, damp areas between your toes, unless there has been any bleeding. If there has, use dry dressings instead. Any signs of athlete’s foot can be treated with surgical spirit, but, if that doesn’t work, use an antifungal powder or spray from the chemist

• Your toenails should be cut or filed straight across, unless a state-registered chiropodist (also called a podiatrist) advises otherwise. Sharp corners can be filed over with a foot file or an emery board

• Corns and calluses (hard skin) are best left to the state-registered chiropodist/podiatrist who will either provide or recommend specific protection for the affected areas. Lint pads or cushion soles may be a useful temporary protection for affected areas if you can’t get to see the chiropodist/ podiatrist straight away

• Get medical advice immediately if you see any signs of ulceration or infection developing anywhere on your feet

Neuropathy in the feet

Neuropathy makes the foot less sensitive to pain and temperature. In its early stages, people often complain of pins and needles or a feeling that they are ‘walking on cotton wool or pebbles’.
When the ability of your foot to feel is reduced, you’re less likely to notice accidental injuries or infection, which will lead to increased damage if
nothing is done. In some cases, skin breaks down over a part of the foot that has experienced sustained pressure, because you don’t feel the discomfort that
would otherwise make you shift your position.
If you are suffering from some degree of neuropathy, you have to get into the habit of checking your feet every day for any cuts or wounds that didn’t
hurt at the time.
The easiest way is to make a regular foot care programme part of your daily routine. It is also important to check the water temperature with your
hand before getting into a bath, and to avoid ‘toasting your toes’ in front of the fire.

Dryness

Loss of elasticity or dryness in the skin of your feet can be associated with neuropathy and a poor blood supply, but it can develop even when you have good circulation and a normal amount of feeling.
You may notice that your skin is becoming dry even if you haven’t had diabetes for very long, and be inclined to dismiss it as just a minor nuisance. However, dry and flaky skin is much less supple because it is not protected by the sweat and natural oils from the everyday pressures and frictions of walking. When the skin on your feet is very dry, you’re more prone to the formation of calluses and corns, and also to splits around the edges (known as fissures).
You can help to replace some of the lost natural moisture by applying a good hand cream every day (to your feet) and using a foot file or pumice stone to remove dead skin. Do be gentle, though, and never, ever use chemicals designed to remove corns and calluses or try to cut them away with blades because you could easily injure yourself.

Changes in the shape of your feet

These can take place over a period of time as a result of neuropathy. The bones underneath may become more prominent as a results of changes in the fatty pad under the ball of your foot. The front part of your foot may spread and your toes may claw. When the tissues under your foot are strained, you may get pain in your heel.
Usually, these changes are a result of minor alterations in the shape of your foot, but don’t forget that they could still mean that you need new shoes to get a better fit.

Expert foot care

As a person with diabetes, you are eligible for treatment from a state-registered chiropodist/podiatrist on the NHS – your GP or health centre should have a list of local practitioners. Many people are perfectly able to look after their own feet, but anyone who has
a physical or visual disability or any of the complications listed above should have regular appointments with a state-registered chiropodist/podiatrist.

Preventing complications from occurring

You are probably feeling rather alarmed after reading about all these possible complications, so it’s worth emphasising again that they can all be prevented by careful attention to diabetes care and blood glucose control.
Remember that complications are not inevitable – and that you have an important role in prevention.

KEY POINTS

• Diabetes can affect the eyes by causing cataracts or damage the back of the eyes – called retinopathy

• Early detection and treatment of eye problems are very effective at preventing progression

• Kidney damage occurs in a minority of patients and can be detected early by a urine test for albumin

• Careful control of blood pressure is an essential part of treatment of diabetes and can protect against kidney complications and hardening of the arteries

• Nerves can also be damaged, and feet and hands need to be checked regularly

• Lowering blood cholesterol by diet and/or medication can reduce the risk of heart attacks and stroke

• Foot care is extremely important in preventing complications

• Feet should be inspected and washed daily, and nails should be cut straight across with sharp edges smoothed off with a file

• Moisturisers can help prevent skin dryness

• Feet should be checked once a year by a health-care professional