What is HIV-Associated Lipodystrophy?
HIV-associated lipodystrophy refers to an unwanted side effect of antiretroviral therapy (ART), a type of treatment for HIV. This occurs due to changes in how the body stores fat, first observed in 1997 among people undergoing ART.
Lipodystrophy can show up in two distinct ways: lipohypertrophy, where fat accumulates and lipoatrophy, where fat is lost. Some patients may experience both conditions simultaneously.
Lipoatrophy tends to happen on the face, buttocks, arms, and legs, while lipohypertrophy often appears in the central parts of the body like the abdomen, resulting in belly obesity, an enlarged breast region, additional fat on the neck, or fatty lumps called lipomas.
These changes in someone’s physical appearance, particularly facial fat loss, can lead to anxiety problems, lowered self-confidence, dysfunction of sexual behaviors, and feelings of social isolation. These changes can significantly affect a person’s quality of life, including their willingness to stick to their ART treatment.
Lipodystrophy can also lead to health complications including insulin resistance (a precursor to diabetes), high levels of fats in the blood (hyperlipidemia), and dysfunction of the endothelium, the inner lining of blood vessels, which can increase the chances of developing heart disease. Therefore, identifying and managing HIV-associated lipodystrophy promptly is vital to patient health.
What Causes HIV-Associated Lipodystrophy?
The precise cause of lipodystrophy, a disorder that affects the way the body uses and stores fat, is still unclear. The use of specific antiviral drugs, namely ‘Nucleoside Reverse Transcriptase Inhibitors’ (NRTIs) like zidovudine and stavudine, has been associated with the development of lipoatrophy, a type of lipodystrophy where fat is lost from certain areas of the body. Using newer drugs like abacavir or tenofovir could prevent this condition from progressing. On the other hand, another type, called Lipohypertrophy, which is characterized by the abnormal gain of fat in some body parts, can sometimes happen when using drugs known as ‘Protease Inhibitors’ (PIs). Unfortunately, stopping or switching these medications doesn’t seem to reverse this fat gain.
When we talk about lipodystrophy, it’s important to separate these two types – lipoatrophy and lipohypertrophy – to better understand what causes them.
In regards to lipoatrophy, NRTIs have been identified as a significant risk factor. Especially stavudine and zidovudine are notorious for causing this condition. One study suggested that only 5% of patients on abacavir developed lipoatrophy, compared to 38% on stavudine. Another study found that none of the patients on tenofovir developed lipoatrophy even after almost three years, while half of the patients on stavudine did. Other types of antiretroviral drugs, used to treat HIV, can also cause lipoatrophy, especially when used alongside NRTIs. However, it’s firmly established that PIs alone do not cause lipoatrophy. Other risk factors include older age, co-infection with hepatitis C, higher amounts of HIV virus in the body and lower counts of CD4 cells, the immune system’s key defenders, at the start of HIV treatment.
Contrary to lipoatrophy, lipohypertrophy tends to be influenced by factors related to the patient, including older age, being female, and having a higher percentage of body fat. Lifestyle choices such as a high-calorie diet leading to high baseline levels of triglycerides also pose a risk. On the other hand, a diet rich in fiber and protein may help prevent fat buildup.
There’s no clear evidence indicating that specific antiretroviral drugs lead to fat accumulation, although there’s some indication that antiretroviral therapy (ART), especially when it includes PIs, may be linked to central fat accumulation. Despite this, studies haven’t been able to definitively establish a link between ART, especially PI use, and fat accumulation in individuals with HIV.
Risk Factors and Frequency for HIV-Associated Lipodystrophy
HIV-associated lipodystrophy, a condition affecting the body’s fat stores, is hard to measure accurately due to varying definitions. However, experts believe that anywhere from 10% to 80% of all people living with HIV worldwide may have the condition. Thankfully, newer HIV drugs are thought to be less likely to cause lipodystrophy compared to older treatments.
In a 2005 study of 452 patients, the following percentages were observed in those living with HIV:
- 35% showed signs of fat loss (atrophy)
- 44% showed signs of fat buildup, specifically in the belly area (central adiposity)
- 14% showed signs of both fat loss and fat buildup
Interestingly, the prevalence of these conditions seems to change over time. After a year, for example:
- 22% of the patients developed new fat loss
- 16% of the patients who initially had fat loss no longer had it
- 23% of the patients developed new fat buildup
- 15% of the patients who initially had fat buildup no longer had it
Signs and Symptoms of HIV-Associated Lipodystrophy
When assessing patients potentially suffering from side effects related to antiretroviral therapy, doctors take into account several important details. This includes changes in the patient’s physical appearance associated with antiretroviral use, the specific medications used, and the duration of treatment. An evaluation for existing medical conditions like diabetes, high cholesterol, high blood pressure, and heart disease is also crucial. Furthermore, their lifestyle choices such as diet, exercise routine, smoking habits, alcohol and illicit drug use, and reports of sleep issues need reviewing. The emotional well-being of patients, including possible anxiety, depression, and feelings of low self-worth, should be addressed, as these might interfere with adherence to their prescribed regimens.
During the physical examination, the practitioner measures the patient’s body mass index, waist circumference, and blood pressure, and checks for clinical signs of lipodystrophy (abnormal body fat changes). Doctors also examine patients for lipoatrophy, shown by a loss of fat in specific body areas, including the arms, legs, face, and buttocks. Certain signs, like thin limbs with visible veins, sunken cheeks, or hollow-looking eyes, may suggest this condition. Lipohypertrophy, on the other hand, is the abnormal accumulation of fat in certain areas like the abdomen, back of the neck (resulting in a “buffalo hump”), breasts, front neck, and jaw area. This condition might also cause fatty lumps (lipomas) to form.
Lipoatrophy or loss of fat tissues are represented by the following physical signs:
- Loss of fat in face, arms, legs, abdomen, or buttocks
- Bony appearance due to visible veins and muscles
- Sunken eyes and cheeks
Central lipoatrophy, which denotes loss of fat in the abdominal area, reveals scant pinchable fat but an increased waist circumference due to more fat inside the abdomen.
Lipohypertrophy or excessive fat accumulation, on the other hand, is characterized by:
- Expansion of abdominal girth
- Buffalo hump in the back of the neck
However, to diagnose lipohypertrophy, it’s important to differentiate it from general obesity. It can be distinguished from obesity by an absence of subcutaneous (under the skin) fat. Over time, fat may also accumulate in liver tissue and muscles.
Testing for HIV-Associated Lipodystrophy
If you’re undergoing Antiretroviral Therapy (ART) for HIV, your doctor will routinely check for lipodystrophy. Lipodystrophy is a condition that can cause unusual fat buildup or loss. Checking your belly size, hip size, and the distance around the middle of your upper arm is a way to monitor for lipodystrophy. Keeping track of your weight and body mass index (BMI) is also important and can help in spotting any changes early on, as addressing fat accumulation early is usually more successful than trying to reverse it later.
Lipodystrophy associated with HIV is often identified based on physical changes in your appearance. Since people suffering from HIV-associated lipodystrophy often encounter metabolic issues, tests for lipid profile (fats in the blood) and glucose tolerance should be done preferably before starting ART, and repeated every six months. A test known as Hemoglobin A1c might be used, but it might not accurately reflect high blood sugar levels due to faster red blood cell replacement in people with HIV. Regular liver and kidney function tests are also necessary.
Accumulation or loss of fat can also be monitored via scans such as computed tomography (a type of X-ray), dual-energy X-ray absorptiometry, or magnetic resonance imaging (MRI). However, these tests aren’t more reliable than your own observations or physical examinations and are costlier. It’s more beneficial to regularly measure body proportions, although different observers may record slightly different results, making them a little less dependable.
For those with HIV-associated lipodystrophy, here are some recommended checks:
- Waist Measurement: For men, belly circumference more than 102 cm and for women, more than 88 cm is abnormal. This may indicate built-up fat and needs further investigation.
- Weight and Body Mass Index (BMI): Regular checks and comparisons with waist size can be informative.
- Fasting Lipid Profile: Both lipoatrophy (fat loss) and lipohypertrophy (excess fat) are accompanied by high triglycerides (a type of fat) and low good cholesterol. Before starting with ART, a fasting lipid profile should be checked and then yearly.
- Glucose Metabolism Test: This should be done routinely to check your body’s ability to process sugar.
Treatment Options for HIV-Associated Lipodystrophy
Treating HIV-related lipodystrophy depends on the particular symptoms the patient is showing. This disease has two types. Lipoatrophy, which is a loss of fat, and lipohypertrophy, which is an unusual increase in body fat.
Lipoatrophy treatment primary consists of altering the particular treatment the patient is receiving for their HIV. Certain types of HIV medications, known as stavudine and zidovudine, may need to be switched out for others like tenofovir or abacavir. This approach has shown to improve lipoatrophy symptoms in numerous clinical research studies. Another possibility is to switch to medicines that don’t contain a class of drugs called nucleoside reverse transcriptase inhibitors (NRTIs) and instead contain protease inhibitors. This has shown to increase body fat in limbs but could potentially increase cholesterol and triglyceride levels in the blood.
However, it’s important that the patient’s overall health and the effectiveness of their current HIV treatment are considered before making any changes. Switching from a protease inhibitor to another type of drug may not yield any benefits. Some medications, for instance, thiazolidinediones, might be considered, but their benefits are not proven and are still under investigation. If insulin resistance is suspected, a medication called pioglitazone may be tried.
Finally, do note that although these changes could improve lipoatrophy in limbs, they have little effect on facial lipoatrophy. For the face, plastic surgery might be the only effective treatment. This could involve injecting fillers or transplanting fat from another part of the body.
When dealing with lipohypertrophy, lifestyle changes are the key. This includes diet and exercise, and in cases of glucose intolerance or diabetes, the addition of a medication called metformin might be beneficial. In order to reduce excessive belly fat, a medication called tesamorelin, a growth hormone-releasing hormone analog, may be used but only with caution due to its documented side effects and temporary benefits. Surgical means like liposuction could be considered as a last resort, but these have varied success rates and carry a high likelihood of recurrence.
Patients may also need treatment for high cholesterol or other lipid abnormalities, typically managed with a class of drugs called statins, fibrates, or ezetimibe, but they each come with potential drawbacks, including unfavorable interactions with some HIV treatments. Therefore, they should be used carefully, considering other medications the patient is taking.
What else can HIV-Associated Lipodystrophy be?
When trying to diagnose lipoatrophy, doctors will need to rule out the following potential conditions:
- Malnutrition
- Hyperthyroidism
- AIDS-wasting syndrome
- Anorexia nervosa
- Cachexia (general physical wasting and malnutrition)
Similarly, if the diagnosis is lipohypertrophy, doctors will consider other possible conditions such as:
- Cushing syndrome
- Excessive use of glucocorticoids (types of steroids)
- Simple obesity
What to expect with HIV-Associated Lipodystrophy
Lipodystrophy associated with HIV, a condition where abnormal fat distribution occurs, can get worse if treatments involving protease inhibitors and a type of medicine called thymidine analog NRTI continue. When this happens, changes in the person’s physical appearance and self-confidence may lead to them not following their HIV treatment regimen as directed, which can ultimately lead to the treatment not working.
Additionally, these conditions can also lead to changes in blood lipid levels and alterations in how the body manages glucose (sugar), both of which increase the risk of developing heart disease in these patients. Detecting and managing these metabolic complications associated with HIV early can prevent these conditions from worsening and, in some cases, may even help reverse the effects of lipodystrophy.
Possible Complications When Diagnosed with HIV-Associated Lipodystrophy
HIV-associated lipodystrophy can cause a great deal of emotional stress, often leading to feelings of depression, low self-esteem, and social isolation. Some people may avoid regular medical care because they fear this condition could make their HIV diagnosis more evident to others.
This condition can also cause various health problems, including high cholesterol and insulin resistance. These complications can increase the risk of heart disease caused by the buildup of fatty deposits in the arteries. Neck enlargement is another effect of the condition and can lead to neck pain and sleep apnea.
Furthermore, lipodystrophy can significantly increase belly fat, leading to feelings of discomfort and swelling in the abdomen. It may also cause gastroesophageal reflux, a condition typified by stomach acid flowing back into the esophagus.
Main Concerns:
- Emotional distress, including depression, low self-esteem, and social isolation
- Fear of revealing HIV status due to visible symptoms caused by lipodystrophy
- Increased risk of heart disease due to high cholesterol and insulin resistance
- Neck enlargement leading to neck pain and sleep apnea
- Increased belly fat, causing abdominal discomfort and bloating
- Gastroesophageal reflux caused by increased abdominal girth
Preventing HIV-Associated Lipodystrophy
Teaching patients about their treatment is crucial for identifying possible side effects and understanding the course of their treatment, especially when beginning medication for HIV. Drugs like stavudine and zidovudine, which are known to potentially cause fat distribution changes in the body (a condition called lipodystrophy), should be avoided to lower the risk of getting this disease. Today, these drugs aren’t the primary treatment for HIV anymore. If a patient is already using these medicine, they should consider swapping to a different type.
Preventing too much fat from accumulating in the body involves promoting a healthy lifestyle. This lifestyle includes regular physical activity, a diet rich in fiber and protein, and closely following any changes in weight. Along with exercise, it’s also important to avoid harmful habits such as smoking. Maintaining such a healthy lifestyle is beneficial and should be strongly suggested to patients with HIV to lower the risk of developing long-term heart disease related to lipodystrophy.
