Bone health

Bone health

In recent years, low bone mass and density, called osteopenia or osteoporosis, has become a widespread problem among people with HIV. Osteopenia is an early stage of bone mineral loss in which the bones become less dense and weaker. This condition does not cause pain or limit movement and is usually treated with diet and exercise rather than medications. Osteoporosis, the more advanced form of the disease, results in fragile bones that can fracture easily. The fracture causes pain, limits movement and reduces quality of life. Osteoporosis is sometimes treated with medications as well as diet and exercise. Note that osteoporosis medications may not be suitable for all people, especially women of childbearing age.

It is still not clear whether bone problems are caused by HAART or by the virus itself. However, many other factors are well known to increase the risk of developing osteopenia or osteoporosis. These include genetics (e.g. your mother had osteoporosis); getting older; low physical activity; being underweight; malnutrition; not enough calcium, vitamin D or protein; poor absorption of nutrients; diseases of the liver, gut or kidneys; and low levels of hormones such as estrogen or testosterone.

Getting enough calcium, vitamin D and protein helps to keep your bones healthy.

Some doctors recommend that people with HIV should have their bone density measured every two years by a special X-ray technique called a DEXA scan. The DEXA compares bone density to standards called T-scores. If the T-score is -1.0 to -2.5, it is considered osteopenia; if it’s below -2.5 (for example, -3.2), it is considered osteoporosis.

Nutrition is always the first line of treatment for osteopenia or osteoporosis, and studies have shown that increasing calcium and vitamin D can restore some bone mineralization.

Mitochondria are often called the “power plants” of human cells

Mitochondria are often called the “power plants” of human cells. All cells contain these microscopic structures, which produce energy for the cell to do its work and stay healthy. Mitochondria convert fats and carbohydrates into a molecule called ATP, the basic fuel for cells. Some cells, like nerve, heart and muscle cells, need a lot of ATP, so they have a lot of mitochondria.

One of the most troublesome toxicities of anti-HIV drugs is that they can damage mitochondria. Some anti-HIV drugs damage the DNA so that the cell can’t produce new mitochondria. When cells get low on mitochondria, they can’t make enough energy to function properly. This condition is called mitochondrial toxicity. It wreaks havoc throughout the body and is thought to contribute to nerve damage (neuropathy), muscle damage (myopathy), heart muscle damage (cardiomyopathy), fat wasting (lipoatrophy) and other health problems. Two anti-HIV drugs associated with the highest risk of mitochondrial toxicity—d4T (stavudine, Zerit) and ddI (didanosine)—are used much less frequently now that we have newer, safer drugs that are less likely to cause this effect.

People experiencing mitochondrial toxicity often have elevated levels of lactate (lactic acid) in the blood. High lactate levels can cause nausea, headaches and fatigue and can make you feel full on a small amount of food (early satiety). Very high lactate levels, called lactic acidosis, can be fatal. If lactic acidosis has occurred or is suspected by your doctor, HAART must be stopped temporarily. Once the acidosis subsides, you may restart HAART with a different combination of anti-HIV drugs.

There are no specific nutrition guidelines for treating mitochondrial toxicity, but some small studies have shown a benefit from B vitamins and L-carnitine supplementation. As well, treatment options for children born with defective mitochondria may provide some guidance. In these children, experts often recommend supplementation with all the cofactors that help the mitochondria function properly (see below). Although there is no scientific evidence that this strategy works for mitochondrial toxicity in HIV, it may offer benefits in terms of feeling better and being able to stay on medications.