AIDS/HIV infection - Definition, Description, Functions, Benefits, Precautions, Risks

Definition : Human immunodeficiency virus (HIV) infection is a complex illness caused by a retrovirus, which is a single-strand virus that replicates by using reverse transcription to produce copies of DNA that become incorporated within the genome of the host cell. The HIV virus destroys a type of white blood cell known as CD4þ T lymphocytes, or T helper cells. These cells are important in maintaining the various functions of the human immune system. When the level of CD4þ T cells in the bloodstream falls, the patient loses the ability to fight off bacteria, viruses, and fungi that would not cause disease in a person with a strong immune system. Infections that occur in people with weakened immune systems are called opportunistic infections.

Acquired immunodeficiency syndrome (AIDS) is an advanced form of HIV infection in which the patient has developed opportunistic infections or certain types of cancer and/or the CD4þ T cell count has dropped below 200/mL. According to the Centers for Disease Control and Prevention (CDC), an estimated 1,039,000 to 1,185,000 persons in the United States were living with HIV/AIDS at the end of 2003, with 24–27% undiagnosed and unaware that they are infected. More than 40 million persons around the world are infected with HIV as of 2007, with approximately 14,000 new infections every day. The disease causes 3 million deaths worldwide each year, 95% of them in developing countries.

Nutritional issues are common in patients with HIV infection. Some problems with diet and nutrition are caused by HIV infection directly while others are related to opportunistic infections or medication side effects. Maintaining adequate food intake and balanced nutrition in patients with HIV infection is complicated not only by the many ways in which the disease can affect the body—including the fact that the virus mutates rapidly—but also by frequent updating of treatment strategies for AIDS, including nutritional therapy. As a result, nutritional care of patients with AIDS must be tailored to each person and reviewed carefully every few months. In 2004, the American Dietetic Association (ADA) and the Dietitians of Canada (DC) issued a position statement on the care of persons with HIV infection that said, ‘‘Individualized nutrition care plans will be an essential feature of the medical management of persons with HIV infection and AIDS.’’ The ADA has a specialized dietetic practice group (DPG) for AIDS and HIV patients that can be contacted from the website listed below.

Origins : AIDS is a relative newcomer to the list of major infectious diseases. According to the National Institutes of Health (NIH), researchers think that HIV originated in a species of chimpanzees native to west equatorial Africa and jumped the species barrier into humans through hunters’ contact with the blood of infected chimpanzees—most likely somewhere in western Africa in the second half of the twentieth century. The earliest known case of HIV infection was found in a blood sample collected from a man in Kinshasa in the Congo in 1959.

The first cases of AIDS were not diagnosed in the United States until June 1981, when the CDC reported a cluster of five cases of an opportunistic lung infection among homosexual men in Los Angeles. In the first 15 years of the epidemic, there were no effective treatments for HIV infection (there is still no cure as of 2007). As a result, many patients turned to alternative dietary treatments to help them manage the nausea, weight loss, and other symptoms associated with the infection. Alternative food-related therapies that were used in this period included:

• Herbal compounds used in traditional Chinese medicine (TCM) for the treatment of fevers or energy deficiency, particularly medicines containing astragalus (Astragalus membranaceus).
• Western herbal preparations recommended by naturopaths, including goldenseal (Hydrastis canadensis), licorice (Glycyrrhiza glabra), osha root (Ligusticum porteri), and echinacea.
• Detoxification diets, including the Master Cleanser lemon juice diet.
• Juice fasts, often taken together with laxatives or colonics.
• Nutritional supplements, particularly blue-green algae, zinc, vitamin C, beta-carotene, and catechin (an antioxidant).
• Vegetarian and raw food diets.

Prior to 1996, nutritional management of AIDS patients focused largely on weight loss and wasting, sometimes called the ‘‘slim disease.’’ After the introduction of highly active antiretroviral therapy (HAART) in 1996, however, nutritionists were confronted with a range of other dietary problems related either to the new drugs or to prolonged survival itself. HAART is not one drug but a combination of various antiretroviral agents given to patients to prevent the virus from replicating and to discourage mutations of the virus. The drugs must be taken in combination because no medication by itself is able to suppress HIV for very long. One early problem with HAART was the complicated dosing schedules of the different drugs prescribed for an individual patient. To encourage adherence to treatment schedules (which must be at least 98% complete to protect the patient from developing a strain of the virus resistant to HAART), some pharmaceutical companies developed fixed-dose combinations. A fixed-dose combination is a medication in which several antiretroviral drugs that

are known to work well together are combined in a single pill.

Guidelines for offering HAART treatment to patients were published in the late 1990s because the drugs have so many adverse effects (including hair loss, muscle cramps and pains, kidney or liver failure, insomnia, inflammation of the pancreas, dizziness and mental confusion, headache, nausea and vomiting, and numbness in hands or feet) that many patients were not compliant with dosage schedules and developed drug-resistant mutations of the HIV virus. Recommendations for HAART have been revised several times by the U.S. Department of Health and Human Services. The following is the most recent set of standards, issued in October 2005:

• All patients with history of an AIDS-defining illness or severe symptoms of HIV infection should receive antiretroviral therapy regardless of CD4þ T cell count.
• Antiretroviral treatment is recommended for asymptomatic patients with less than 200 CD4þ T cells/mL.
• Asymptomatic patients with CD4þ T cell counts of 201—350 cells/mL should be offered antiretroviral treatment.
• For asymptomatic patients with CD4þ T cell of greater than 350 cells/mL and plasma HIV RNA greater than 100,000 copies/ml, most experienced clinicians defer therapy but some clinicians may consider initiating antiretroviral treatment.
• Antiretroviral therapy should be deferred for patients with CD4þ T cell counts of greater than 350 cells/mL and plasma HIV RNA less than 100,000 copies/ml.

It is this set of guidelines for HAART that nutritionists currently work with when planning healthful diets for patients with HIV infection and AIDS.

Description : While there is no standard ‘‘HIV diet’’ or ‘‘AIDS diet’’ because patients’ symptoms, medication regimens, and corresponding nutritional needs vary so widely, there are general practices followed by registered dietitians who work with doctors and other health care professionals to care for these patients.

Dietetics consultation and follow-up

Patients with HIV infection should consult a registered dietitian (RD) as soon as possible after diagnosis, because good nutrition is essential to maintaining a normal level of activity and self-care as well as supporting the patient’s immune system. RDs use several screening questionnaires to evaluate patients for potential nutritional problems. On the patient’s first visit, he or she is given a quick nutrition screen or QNS to fill out. The QNS identifies such problems as unintentional weight loss, nausea, difficulty swallowing, and diarrhea. The dietitian then measures the patient’s height, weight, skinfold thickness, and the circumference of the muscles on the patient’s midarm. These last two measurements are needed in order to monitor changes in body fat distribution and muscle wasting that often accompany HIV infection.

The next step in the initial assessment the patient’s completion of a food intake record (FIR). The patient is asked to record everything he or she eats or drinks in a 24-hour period, including snacks and alcoholic beverages. If possible, the patient will fill out two FIRs, one for a working day and one for a weekend day or holiday. The FIR allows the dietitian to evaluate the patient’s usual eating habits, portion sizes, food preferences, and average calorie intake. It also establishes a baseline for the individual patient, so that loss of appetite later on or other nutritional problems can be detected as quickly as possible.

Follow-up visits to the dietitian are scheduled according to the degree of the patient’s nutritional risk. The American Dietetic Association and the Los Angeles County Commission on HIV Health Services use the following timelines for HIV patients at nutritional risk:

• Low risk: The patient’s weight is stable, with a balanced and adequate food intake; normal blood levels of cholesterol, triglycerides, and glucose; no evidence of kidney or liver disorders; regular physical exercise; and low levels of psychosocial stress. Low-risk patients are evaluated by the RD as needed, but at least once a year.
• Moderate risk: The patient is obese or suffers from changing patterns of body fat distribution; has high blood cholesterol levels or high blood pressure; has developed an eating disorder, nausea, vomiting, or diarrhea; has been recently diagnosed with type 2 diabetes or food allergies; is in recovery from substance abuse; or is under psychosocial stress. Moderate-risk patients should be seen by the RD within a month.
• High risk: The patient is pregnant; suffers from poorly controlled diabetes; has lost 10% of body weight over the previous 4–6 months; has lost 5% of body weight in the previous 4 weeks; has dental problems, involvement of the central nervous system, severe nausea or vomiting, severe pain on swallowing, or chronic diarrhea; has one or more opportunistic infections; or is under severe psychosocial stress. These patients should be seen by an RD within one week.

In addition to assessment of the patient’s nutritional needs, RDs also evaluate his or her living situation and other issues that may affect receiving adequate nutrition.

Specific issues in nutritional care

of HIV patients

NAUSEA, VOMITING, AND DIARRHEA. Nausea and vomiting are common symptoms of HIV infection as well as side effects of HAART. They can lead to long term damage to the esophagus and dental problems as well as weight loss and inability to take needed medications. About 30% of patients develop nausea and vomiting within 1 to 4 weeks following infection as part of a condition called acute retroviral syndrome or ARS, which resembles influenza or mononucleosis. Most patients, however, develop nausea, vomiting, and diarrhea later on in the course of the disease as side effects of HAART or from opportunistic infections of the gastrointestinal system. Patients with HIV infection are highly susceptible to such diseases as giardiasis, cryptosporidiosis, listeriosis, Campylobacter infections, and Salmonella infections.

Treatment of nausea, vomiting, and diarrhea in patients with HIV infections may require a number of diagnostic tests and imaging studies as well as evaluation of the patient’s medications in order to determine the cause(s) of the symptoms.

LIPODYSTROPHY. Lipodystrophy is the medical term for the redistribution of body fat that sometimes occurs in patients with HIV infection as a result of HAART, genetic factors, the length of time a person has been HIV-positive, and the severity of the disease. It is not completely understood as of the early 2000s why antiretroviral drugs and other factors have this effect. The patient may notice new deposits of fat at the back of the neck (sometimes called ‘‘buffalo humps’’) and around the abdomen. Conversely, fat may be lost under the skin of the face, resulting in sunken cheeks, or lost under the skin of the buttocks, arms, or legs. Lipodystrophy is not necessarily associated with weight loss.

Lipodystrophy may be accompanied by other changes in the patient’s metabolism, particularly insulin resistance and higher levels of blood cholesterol and triglycerides. One recommendation nutritionists often give to patients with lipodystrophy and metabolic changes is to follow the Mediterranean diet, which is high in fiber-rich whole grains and vegetables and low in saturated fats. Another recommendation is to maintain a schedule of regular physical exercise (particularly weight training), which has been shown to lower insulin resistance and decrease abdominal fat deposits.

WASTING. Wasting refers to rapid unintentional weight loss (usually defined as 5% of body weight over a period of 6 months) combined with changes in the composition of body tissue. Specifically, the patient is losing lean muscle tissue and replacing it with fat. The patient’s outward appearance may not be a reliable guide to wasting, particularly if he or she also has lipodystrophy. Weight loss associated with wasting may result from nausea and vomiting related to opportunistic infections of the digestive tract as well as from reactions to medication.

Nutrition is the first line of defense against wasting. To help the patient maintain weight, nutritionists recommend raising the daily calorie intake from 17–20 calories per pound of body weight (a guideline used for patients whose weight has been stable) to 25 calories per pound. Patients with wasting syndrome may require as much as 3500 calories per day to maintain their weight. Nutrient ratios should be 15–20% protein, 50–60% carbohydrates, and 25% fats to protect the body’s muscle tissue. Patients who need more calories or protein may benefit from adding such supplements as Ensure or Instant Breakfast to their daily diet. In addition, weight training or other forms of regular exercise help to maintain muscle tissue.

Other treatments for wasting include the use of appetite stimulants to increase food intake and hormonal treatments to build lean muscle tissue, particularly in male patients.

MEDICATION INTERACTIONS. Most medications used in HAART have the potential to cause nausea and vomiting. Some antiretroviral medications should be taken with food to minimize these side effects. Digestive disturbances are the single most common reason given by patients for discontinuing antiretroviral therapy. In some cases, switching to a different combination of drugs helps to relieve nausea, vomiting, or diarrhea.

Function : The function of nutritional education and dietary management in patients with HIV infection and AIDS is to maintain the patient’s energy level and ability to carry out normal activities of daily life; lower the risk of opportunistic infections of the digestive system; and minimize the side effects of HAART on the patient’s ability to eat and enjoy food.

Benefits : The benefits of good nutritional care of patients with HIV infection are prolonged survival, improved quality of life, and fewer or less severe side effects from medical treatment.

Precautions : 

Food safety issues

Food safety is an important concern for patients with HIV infection because their immune systems have difficulty fighting off food- or water-borne disease organisms. While most people can get food poisoning or parasitic infections of the digestive tract if they drink contaminated water or do not prepare food properly, patients with HIV infection can get severely ill as a result of these diseases. Food-borne illnesses are also much more difficult to treat in persons with AIDS or HIV infection, and may lead to malabsorption syndrome, a condition in which the body cannot absorb and make use of needed nutrients in food. The CDC and NIH have brochures with detailed instructions for patients about safety issues in purchasing and preparing foods, particularly when traveling abroad. Basic safeguards include the following:

• Wash hands repeatedly in warm soapy water before and after preparing or eating food. Instant hand sanitizers should be used when away from home.
• Cook all meats, fish, and poultry to the well-done stage; do not eat sushi, raw oysters, or raw meat in any form.
• Do not use unpasteurized milk or dairy products.
• Do not eat raw, soft-boiled, or ‘‘wet’’ scrambled eggs, or Caesar salad made with raw egg in the dressing. Hard-boiled or hard-scrambled eggs are safe.
• Rinse all fruits and vegetables carefully in clean, safe water, and clean all cutting boards and knives that touch chicken and meat with soap and hot water before using these utensils with other food items.
• Keep all refrigerated foods below 40F; check expiration dates on food packaging.
• Completely reheat leftovers before eating, and do not eat leftovers that have been stored in the refrigerator for longer than 3 days.
• Do not drink water that comes directly from lakes, streams, rivers, or springs, and ask for drinks without ice in restaurants.

HIV patients with special needs

Patients with special needs include those with limited food budgets or without access to a kitchen for preparing their own food. Advice regarding community resources and other forms of assistance can be found on the website of the Tufts University School of Medicine Nutrition/Infection Unit at the URLs listed under ‘‘Other’’ below. 

CAM dietary treatments

In general, multivitamins, other dietary supplements, or herbal teas prepared by reliable manufacturers and approved by the patient’s physician are useful complementary treatments for HIV patients. Traditional Chinese medicines made outside the United States, however, should be used with great caution as their purity cannot be guaranteed.

Patients interested in a vegetarian diet should consult their physician and nutritionist before starting one; raw-food vegetarian diets should be avoided because of the increased risk of contracting foodborne diseases. Detoxification diets and colonics are risky practices for HIV patients and should not be used.

Risks : There are no known risks to nutritional management of patients with HIV infection by qualified professionals working with the patient’s physicians and nurses. There are few risks to the use of naturopathic dietary supplements or herbal formulas provided that the patient reports the use of alternative therapies to the medical care team and does not use them as substitutes for HAART or other mainstream medications.

Research and general acceptance : Research in the field of nutrition for HIV patients is ongoing and can be expected to produce revised guidelines for dietary management every few years for the foreseeable future. These changes will result as much from mutations in the disease organism as from discoveries of new drugs and other forms of treatment for HIV infection.