Some people with HIV have a higher risk of developing Type 2 diabetes. According to one recent study, men with HIV on treatments are more than four times more likely to develop diabetes than HIV negative men. Another study suggested that HIV positive women on a protease inhibitor are three times more likely to develop diabetes than women on other drugs and HIV negative women. If that wasn’t enough to worry about, having a CD4 count below 300 at some point also appears linked to the development of the condition.
Several studies show diabetes may be associated with HIV infection itself, and not only HIV treatments, and that its incidence may increase with longer exposure to treatment.
Diabetes is caused by a reduction in the body’s ability to control blood sugar levels. As we age and gain weight we are all more likely to develop diabetes, so everyone, regardless of HIV status, should be regularly screened for hyperglycaemia (high blood sugar). This is when too much glucose circulates in the blood. A measurement of over 11mmol/l (or 7mmol/l while fasting) is usually considered a diagnosis of hyperglycaemia and therefore diabetes.
There are two main types of diabetes:
Type 1 Often diagnosed in childhood, is caused by the body’s failure to produce enough insulin, preventing cells from using glucose properly.
Type 2 is caused by the body failing to respond to insulin. It’s more common than Type 1 and can be caused by being overweight and a lack of exercise. It develops as we get older and may also occur as a side effect of some antiretroviral drugs.
How does diabetes develop?
Our cells need glucose for energy. Over time, they may be less able to take up the glucose that builds up in the bloodstream after a meal. When this happens, people are said to be ‘insulin resistant’ as they require more insulin to maintain glucose levels within the normal range. As insulin resistance increases, our fat cells release fatty acids to supply our livers with more raw materials to make glucose, but this fails to restore normal glucose levels.
Eventually glucose levels rise to a point where they trigger physical symptoms of hyperglycaemia such as tiredness, frequent urination, constant thirst due to loss of fluid, blurred vision and weight loss. In Type 2 diabetes, more serious problems can arise such as lesions in the retina of the eye, kidney disorders, nerve damage (especially in the legs), impotence, bacterial or fungal skin infections and heart disease (angina, stroke or heart attack).
HIV drugs and Type 2 diabetes
Studies suggest between two and ten per cent of people taking HIV medications develop Type 2 diabetes and the prevalence may be growing as people spend longer on treatment. In the D:A:D (Data Collection of adverse events of anti-HIV drugs) study of 25,000 people living with HIV, researchers found PI use was associated with a six per cent increase in diabetes for each year on that class of drug.
If you are on HIV treatments you should have your glucose levels monitored regularly so steps can be taken to reduce rising glucose levels before diabetes develops.
Type 2 diabetes may emerge rapidly after beginning a new drug combination. Extra weight around our middles predisposes us to Type 2 diabetes because fat surrounding organs is highly insulin resistant.
Increased heart disease risk
Developing diabetes may put us at greater risk of heart disease in future. When large amounts of glucose are present in our blood, the sugar becomes attached to low-density lipoprotein (LDL) or ‘bad’ cholesterol. This causes cholesterol to be oxidised more easily. It’s taken up into the wall of blood vessels where it forms plaques that contribute to hardening of the arteries and heart disease.
When sugar attaches to high density lipoprotein (HDL) or ‘good’ cholesterol, the liver finds it less easy to remove this cholesterol from the bloodstream. High glucose levels also increase blood clotting and reduce the flexibility of blood vessels. These factors contribute to heart problems.
Hep C coinfection
Being coinfected with hepatitis C appears to further increase the risk of developing diabetes and hyperglycaemia, especially for those of us over 40 or with a previous history of pancreatitis.
Fitness factors
We can help to normalise glucose levels by increasing the amount of daily exercise we do. Ideally we should try to raise our heart rate above normal levels for at least 20 minutes each day. Brisk walking, swimming, cycling, jogging or aerobics are good for this.
Fat factors
People with diabetes should also eat more fibre, choosing wholegrains, beans, and fresh fruit and vegetables and cutting back on saturated fats (butter and cream), trans- fatty acids (margarine) and hydrogenated fats (in prepared foods such as cakes, biscuits and pizza).
We should also eat more polyunsaturated fats like cornflower, sunflower or safflower oil and soya beans. You should consult a dietitian with specialist knowledge of HIV before you start a diet designed to deal with diabetes.
Drug treatments for Type 2 diabetes
If dietary and exercise changes are insufficient to bring your glucose levels back to normal, and you have limited antiretroviral options to switch to, you may need additional drugs to treat diabetes. People starting drugs for diabetes should continue to exercise and stick with dietary changes, to help lower blood sugar.
Drug therapy for diabetes aims to lower the peak in glucose levels after we eat, since a rise in glucose levels after eating plays an important role in stimulating insulin resistance and developing complications such as retinal, nerve or kidney damage.
Oral therapy
Therapy may also include insulin injections, or a combination of oral tablets to normalise glucose levels. Insulin therapy is usually reserved for severe cases of Type 2 diabetes, although some experts believe that if it could be used earlier, remission of Type 2 diabetes might be achieved more frequently.
A question of age
As we live longer with HIV, it’s natural we may have to deal with other age-related health problems. This makes staying healthy through diet, exercise and choosing drug therapy even more important. If you are concerned that you are at risk of developing diabetes, discuss your concerns with your GP.
This is an edited version of an article by Robert Fieldhouse which first appeared in Positive Nation