The clinician should ensure that patients with human immunodeficiency virus (HIV)-associated weight loss are receiving effective antiretroviral (ARV) therapy.
Key Point:
Weight loss is a symptom that warrants a carefully executed diagnostic evaluation for correctable or treatable confounding conditions.
Assessment of Body Composition
The clinician should measure and record the weight of HIV-infected patients at each visit.
For the purposes of this guideline, the following definitions concerning body composition will be used:
- Body weight (BW) is the total mass constituting all cellular and non-cellular components and can be simply measured by an office scale.
- The body cell mass (BCM) includes all non-adipose cells as well as the aqueous compartments of the fat cells.
- The fat compartment (Fat) represents the non-aqueous component of adipocytes.
- The lean body mass (LBM) represents the BCM and extracellular material (EM) exclusive of fat.
The body composition compartments relate as follows:
BW = BCM + EM + Fat
LBM = BCM + EM
Key Point:
The clinician should be vigilant for HIV-associated malnutrition, even in patients who appear to be maintaining their usual body weight. Weighing the patient should not be the sole method used to detect nutritional deficiencies.
Refer to Table 1 in the original guideline document for information on clinical determination of changes in body composition.
Assessing Nutritional Status
A careful nutritional assessment should be conducted by a registered dietitian for any patient who has involuntary weight loss of at least 5% of the usual body weight (UBW), demonstrates clinical evidence of LBM loss, or follows a restrictive diet involving major food groups.
Key Point:
A thorough medical history and a focused physical examination are the most valuable tools in assessing nutritional status.
Energy Expenditure
Key Point:
Resting energy expenditure in all stages of HIV/acquired immunodeficiency syndrome (AIDS) may be increased by >10% when compared with non-HIV-infected individuals.
Weight Loss
Pathophysiology
Decreased Nutrient Intake
When patients present with dysphagia or odynophagia, the clinician should evaluate for causes of neoplasms, stomatitis, and/or esophagitis, especially when the patient's CD4 count is <200 cells/mm3.
After active opportunistic diseases have been excluded in patients with voluntary restricted caloric intake, clinicians should consult with or refer the patient to a dietitian, psychiatrist/psychologist, or social worker.
Key Point:
Dietary restrictions for some highly active antiretroviral therapy (HAART) regimens pose significant barriers to adequate caloric intake and good nutrition. It may be necessary to consider a change in HAART under these circumstances (see Table 2 in the original guideline document for manufacturer's guidelines combining antiretroviral medication and food).
Decreased Nutrient Absorption
For all patients with chronic diarrhea, the clinician should examine for and treat gastrointestinal opportunistic infections (Mycobacterium avium complex, bacterial pathogens such as Salmonella, Cryptosporidium, microsporidia, Isospora, Giardia, Entamoeba, Clostridium difficile), as well as assess for ARV-induced diarrhea.
The clinician should evaluate patients with chronic diarrhea in the setting of weight loss for malabsorption by 3-day fecal fat measurement, D-xylose absorption studies, and jejunal and/or colon biopsy.
Disturbances of Metabolism
The clinician should perform a comprehensive medical evaluation when rapid unintentional weight loss (≥10% of the UBW) occurs over weeks to months because it is frequently associated with a life-threatening opportunistic infection or neoplasm.
Clinicians should consider measuring total and free testosterone levels in all HIV-infected men with changes in libido, loss of LBM, or fatigue.
Key Point:
Because women lose a disproportionate amount of body fat at all stages of HIV infection, malnutrition should be suspected in women demonstrating fat loss.
Key Point:
When weight loss is associated with profound fatigue, postural hypotension, hyperkalemia and/or hyponatremia, clinicians should consider adrenal insufficiency, especially in cases of disseminated M. avium complex and cytomegalovirus (CMV) infection.
Management of Gradual HIV-Associated Weight Loss
Nutritional Supplementation
Although nutritional supplementation is indicated for all patients with weight loss, the clinician should not supplement caloric intake without first addressing reversible causes of weight loss.
Clinicians should recommend the use of "once daily" multivitamin supplements containing selenium (20 to 40 micrograms) for all HIV-infected patients experiencing weight loss.
Clinicians should not recommend high-dose vitamin therapy because this might exacerbate pre-existing gastrointestinal dysfunction and/or anorexia.
Clinicians should consider medical conditions, such as pancreatitis, diabetes mellitus, or renal insufficiency, in planning macronutrient balances.
Treatment of Anorexia
When patients present with anorexia, clinicians should perform a careful review of the medication list to determine whether the anorexia is medication-induced.
Treatment of Non-Infectious Diarrhea
When recalcitrant diarrhea occurs as a complication of HAART, clinicians should consider a change in therapy if suitable alternatives with a high likelihood of successful viral suppression are available (based on HIV resistance testing).
The Role of Exercise
Clinicians should advise patients to participate in a fitness program that uses progressive resistance exercise (PRE).
Anabolic Steroids
Clinicians should exclude specific endocrine abnormalities, such as hypothalamic hypogonadism and hyperthyroidism, before prescribing oxandrolone.
Clinicians should monitor for hypogonadism in eugonadal men who are receiving long-term nandrolone or oxandrolone.
Androgenic Anabolic Steroids
Clinicians should consider short-term (several months) testosterone therapy with supraphysiologic doses, in conjunction with PRE, to achieve BCM increase in selected male patients demonstrating a rapid rate of muscle loss.
Because androgenic anabolic steroids cause virilization, a general recommendation for their use in women cannot be made until further studies have been completed.
Because androgen enhances libido, clinicians should strongly reinforce safer sexual practices for patients receiving androgenic anabolic steroids.
Recombinant Human Growth Hormone
Clinicians should consider prescribing a 12-week course of recombinant human growth hormone (rhGH) after hypogonadism and active opportunistic diseases have been excluded.
Clinicians should discontinue rhGH treatment if no weight gain is observed after the initial 3 to 4 weeks of therapy.
If weight loss continues despite several weeks of rhGH therapy, the clinician should re-evaluate for co-existent opportunistic infections.
The Wasting Syndrome
Clinicians should perform a detailed evaluation for opportunistic infections or malignancies in all patients with wasting syndrome.
Nutritional Intervention in the Wasting Syndrome
The clinician should perform an immediate evaluation to determine the cause of the wasting syndrome.
For patients with conditions that prevent enteral feeding, total parenteral nutrition (TPN) may be indicated for short-term management.
The clinician should monitor supplementation with micronutrients by frequently assessing serum electrolytes and blood glucose in the first several weeks of re-feeding.
Fat Redistribution (Lipodystrophy) Syndromes
Key Point:
Clinicians should consider the possibility of concurrent lactic acidosis and/or hepatic dysfunction in patients with lipoatrophy.
