Energy expenditure and wasting in human immunodeficiency virus infection

Differential metabolic response in AIDS-related chronic protozoal diarrhoea

OBJECTIVE

As the pro-inflammatory cytokine tumour necrosis factor-alpha is greater in microsporidiosis than cryptosporidiosis, there may be a distinct metabolic response between the two organisms.

DESIGN

Male HIV seropositive subjects with an untreated AIDS-defining diagnosis of microsporidiosis or cryptosporidiosis had measurement of oxygen consumption and carbon dioxide production by indirect calorimetry and body composition analysis to express resting energy expenditure (REE) and substrate oxidation per kilogram of metabolically active tissue.

METHODS

Resting energy expenditure (REE), non-protein respiratory quotient (NPRQ), fat and carbohydrate oxidation were calculated from respiratory gas analysis. Fat, fat-free and appendicular muscle masses were measured by dual-energy X-ray absorptiometry. Subjects with protozoal diarrhoea were compared to other newly diagnosed, active opportunistic infections. Controls were asymptomatic HIV-seropositive men matched by peripheral CD4 count.

RESULTS

Seven subjects with microsporidiosis and six with cryptosporidiosis were compared with 24 subjects with other AIDS-defining diagnosis (Pneumocystis carinii pneumonia, cytomegalovirus enteritis and Mycobacterium avium-intracellulare) and 10 controls free from secondary infection. Subjects with cryptosporidiosis had a decreased REE, a significantly increased NPRQ (P< 0.05), decreased fat oxidation (P < 0.05) and increased carbohydrate oxidation compared to microsporidiosis. Subjects with other AIDS diagnoses had an increased REE (P < 0.01) and fat oxidation and decreased carbohydrate oxidation compared to cryptosporidiosis, and a similar metabolic response to microsporidiosis.

CONCLUSIONS

The metabolic response to cryptosporidiosis differs from microsporidiosis and associated weight loss may be mediated by different mechanisms. Metabolism in other AIDS diagnoses, including microsporidiosis, is compatible with a cachectic response.

Determinants of energy intake and energy expenditure in HIV and AIDS

To determine the relative importance of various factors in the causation of wasting related to human immunodeficiency virus (HIV), quantitative analysis and linear structural modeling was performed on energy metabolism data collected longitudinally and prospectively from 33 men positive for the human immunodeficiency virus at 105 time points over a 3-y period before the era of highly active antiretroviral therapy. Measured variables included energy intake, total energy expenditure, resting energy expenditure, rate of change in weight, CD4 count, clinical status, appetite, and mood. Derived variables included energy balance, activity-related energy expenditure, and physical activity level. Relative contributions were assessed by linear structural modeling based on multiple regression expressing results as path coefficients for individual relationships. The primary determinant of energy balance was energy intake (r = 0.80). Total energy expenditure made a very minor contribution to energy balance (r = -0.04). Total energy expenditure was primarily determined by activity level (r = 0.91), which itself was negatively related to the presence of opportunistic infection and CD4 count. Energy intake was related to activity level (r = 0.28) and appetite (r = 0.30), which were closely interrelated (r = 0.59). Such linear structural models allow quantitative importance to be apportioned to factors determining weight change in those infected with HIV and represent a powerful tool for future metabolic studies.

Nutritional supplements combined with dietary counselling diminish whole body protein catabolism in HIV-infected patients

BACKGROUND

Weight loss and protein malnutrition are frequent complications in HIV-infected patients. The effect of an oral nutritional supplement combined with nutritional counselling on whole body protein metabolism was assessed.

MATERIALS AND METHODS

HIV-infected individuals with a body mass index < 21 kg m-2 or CD4-T cells < 500 micro L-1 in stable clinical condition were randomly allocated to [1] receive either oral nutritional supplements (containing 2510 kJ, complete macro- and micronutrients) and dietary counselling (n = 8), or [2] identical monitoring but no supplements or specific nutritional advice (controls, n = 7). Whole body leucine kinetics and leucine oxidation rate were determined by [1-13C]-leucine infusions and lean and fat mass were measured before and 12 weeks after intervention.

RESULTS

Leucine oxidation (protein catabolism) decreased in the group receiving nutritional intervention from 0.33 +/- 0.02 to 0.26 +/- 0.02 micromol kg-1 min-1 after 12 weeks (P < 0.05; P < 0.05 vs. control group) but remained unchanged in the control group. Whole body leucine flux showed a tendency to decrease in the intervention group from 1.92 +/- 0.19 to 1.73 +/- 0.14 micromol kg-1 min-1 (P = 0.07) and remained unchanged in the control group (2.21 +/- 0.16 and 2.27 +/- 0.14 micromol kg-1 min-1, respectively). Lean body mass determined by bioelectrical impedance analysis increased in the nutritional intervention group from 84 +/- 2 to 86 +/- 2 per cent (P < 0.05) and fat mass decreased from 17 +/- 2 to 14 +/- 2 per cent (P < 0.05) of total body weight whereas neither mass changed in the control group. Nutritional intervention had no significant effect on lymphocyte CD4 counts, on plasma TNFR 55, TNFR 75 and ILR 2 concentrations and on quality of life.

CONCLUSIONS

The data demonstrate an anticatabolic effect of nutritional supplements combined with dietary counselling in HIV-infected subjects. They suggest that diminished whole body protein catabolism resulted in a change of body composition (increased lean mass, decreased fat mass).

Beneficial effects of protease inhibitors on body composition and energy expenditure: a comparison between HIV-infected and AIDS patients

OBJECTIVES

(i) To investigate whether protease inhibitor (PI) (nelfinavir)-containing highly active antiretroviral therapy (HAART) affects body composition differently in HIV-infected and AIDS patients without wasting syndrome. (ii) To delineate the changes in resting energy expenditure (REE) under PI therapy, and to determine whether sustained reductions in HIV RNA would decrease REE.

DESIGN

Prospective longitudinal cohort study with individually matched healthy controls.

SETTING

Tertiary care centre at a University Hospital.

METHODS

HIV-seropositive (n = 20) and AIDS patients (n = 17) with a plasma viral load of at least 10000 copies/ml and 37 healthy volunteers were enrolled. All participants were weight stable, free of acute opportunistic infections, and naive to PI therapy. Patients underwent testing of bioelectrical impedance analysis (BIA), indirect calorimetry and food intake, shortly before the initiation of HAART and 24 weeks thereafter.

RESULTS

Both patient groups gained weight, body mass index (BMI), and fat-free mass (FFM) (P < 0.05 versus baseline), whereas only AIDS patients gained fat mass. Increases were more pronounced in the AIDS group. REE was elevated compared with corresponding controls at baseline, and decreased similarly in HIV and in AIDS patients during PI therapy (P < 0.05). The reduction in the viral burden preceded the decrease in REE by several weeks.

CONCLUSION

Body composition and metabolic parameters improved during PI therapy in HIV-infected and AIDS patients without wasting. Although an early reduction in viral load as a result of HAART does not seem to influence REE directly, sustained viral load suppression may promote a decrease in energy expenditure.

Oral supplements as adjunctive treatment to nutritional counseling in malnourished HIV-infected patients: randomized controlled trial

AIMS

To compare nutritional counseling with and without oral supplements in HIV-infected patients with recent weight loss.

DESIGN

Randomized non-blinded controlled trial, stratified for change in antiretroviral treatment at baseline.

PATIENTS

HIV-infected patients with recent weight loss (> 5% of total, and >3% in the last month).

INTERVENTION

Nutritional counseling to increase dietary intake by 600 kcal/day over 8 weeks; in group A (n=24) by normal food, and in group B (n=26) by a range of fortified drink supplements with a calorific value of 0.6 to 1.5 kcal/ml.

METHODS

Body composition by bioelectrical impedance analysis, dietary intake by 24 h recall.

RESULTS

Fat free mass increased from baseline to week 8 (P<0.05) with no difference between groups A and B (P=0.97). Body cell mass and weight gain were not significant and equal between groups. Assessed at weeks 2 and 4, group B patients consumed 11 +/- 6 kcal/kg as supplements, and their total energy intake was 6 kcal/kg higher than in group A (P<0.01). Total energy intake was not different between groups at weeks 6 and 8.

DISCUSSION

Nutritional counseling and oral supplements are both feasible methods to restore food energy intake in malnourished HIV-infected patients. Although normal food intake is partially replaced, oral supplements may improve the adherence to a weight gain regimen.

Use of growth hormone and other anabolic agents in AIDS wasting

Body wasting and loss of lean body mass (LBM) have been associated with increased mortality and disease progression, and reduced quality of life, in patients with human immunodeficiency virus (HIV) infection. The failure of nutritional therapies and, more recently, of effective viral suppression, to consistently restore LBM has prompted investigation of the pharmacologic use of a number of specific protein anabolic agents, including recombinant human growth hormone (rhGH), insulin-like growth factor I (rhIGF-I), and synthetic testosterone derivatives, such as nandrolone decanoate, oxandrolone, and oxymetholone. In a placebo-controlled trial, treatment with rhGH resulted in a significant and sustained increase in weight that was accompanied by an even greater increase in LBM and a decrease in fat, and improvement in treadmill work output. Preliminary data suggest that short-term rhGH treatment may be effective in mitigating weight loss in patients with secondary infections. Open-label studies of nandrolone decanoate suggest that this injectable agent also can increase weight and LBM. Two oral agents, oxandrolone and oxymetholone, can increase weight, but their effects on LBM in placebo-controlled trials have not been reported. Taken together, these studies demonstrate that HIV-infected individuals can regain weight and LBM under the proper therapeutic circumstances. The effects of reversal of wasting on survival and disease progression, long-term safety, and the potential value of these therapies in the treatment of fat redistribution remain to be determined.

Energy expenditure in wasting diseases: current concepts and measurement techniques

Weight loss occurs secondary to many acute and chronic disease states. The measurement of energy balance is crucial to understanding disease-related changes in body composition. This review considers various techniques for measuring energy expenditure in wasting diseases and the current concepts regarding the effect of disease on energy expenditure.

Randomized, controlled trial of caloric supplements in HIV infection. Terry Beirn Community Programs for Clinical Research on AIDS

OBJECTIVE

To compare the efficacy of three nutritional regimens in the prevention of weight loss.

DESIGN

A three-arm randomized controlled trial with primary outcome measure percent change in weight over four months.

PATIENTS

A total of 536 patients with CD4 count <200 cells/mm3 and stable weight, defined as <5% weight loss as determined by a weight measurement 3 to 6 months before randomization were recruited at fourteen administrative units in the United States, each unit consisting of multiple primary care sites.

INTERVENTION

The three arms were 500 kcal daily of caloric supplement with peptides and medium-chain triglycerides plus a multivitamin and mineral supplement, 500 kcal of a caloric supplement with whole protein and long-chain triglycerides plus a multivitamin and mineral supplement, and a multivitamin and mineral supplement only.

RESULTS

There were no significant differences among the three regimens in the percent change in weight (p = .74) and body cell mass (p = .63). On average, 65% of the recommended 500 kcal/day of caloric supplements containing peptides with medium-chain triglycerides and 82% of the 500 kcal/day of the caloric supplement containing whole protein and long-chain triglycerides were consumed.

CONCLUSIONS

Caloric supplements do not promote increases in average weight or body cell mass in weight-stable, HIV-infected adults beyond that offered by a multivitamin and mineral supplement.

Survival and failure to thrive in the SIV-infected juvenile rhesus monkey

In AIDS patients, wasting in adults and failure to thrive in children are common and devastating problems. Weight loss in rhesus macaques infected with simian immunodeficiency virus (SIV) has not been well characterized. The purpose of this study was to determine growth curves in SIV-infected juvenile macaques to determine the effects of SIV infection on body weight and growth. Medical records of seven juvenile male SIV-infected macaques were retrospectively reviewed to determine body weights, survival time, CD4 count, and viral load. Mean age and body weight at the time of inoculation were 63.3 weeks and 2.4 kg, respectively. Mean survival was 73.7 weeks, and mean body weight at the time of death was 3.0 kg, whereas the published mean body weight for this age of male rhesus macaque is 4.1 kg. Compared with the linear growth pattern of normal animals, the growth pattern for the SIV-infected animals exhibited strong nonlinearity with an inflection point at the mean survival of 74 weeks. After this time point, the discrepancy between growth curves for infected and healthy animals increased at a greater rate. Body weight correlated inversely with viral load (r = -0.368; p = .003) but there was no correlation between body weight and CD4 count. The results of this study suggest that failure to thrive is a consequence of SIV infection and may be related to severity of infection.

Palliative care and AIDS: 2 – Gastrointestinal symptoms

With the use of more intensive antiretroviral therapies (highly-active antiretroviral therapy, HAART) particularly in first world countries, reductions in the mortality and morbidity of HIV infection are being seen. However, though the prevalence of symptoms may change, symptom control does continue to be a problem for many people with HIV, particularly as their disease progresses. This is the second of 2 CME articles about palliative care and HIV infection. The first gave a background to palliative care, and covered symptom control of pain1. This article gives suggestions for the treatment of common gastrointestinal symptoms in HIV infection; nausea and vomiting, cachexia and anorexia and chronic diarrhoea.

Syndrome of body fat redistribution in HIV-1-infected patients: relationships to cortisol and catecholamines

OBJECTIVE

Alterations of body fat distribution have been recently reported in HIV-infected patients. We aimed to investigate whether the hormones modulating adipose tissue metabolism could be implicated.

SUBJECTS

We investigated twenty-eight HIV-infected patients who had developed abdominal fat, combined with peripheral lipodystrophy in 25 cases and 'buffalo hump' in 2 cases, but who had otherwise improved on antiretroviral therapies. Twelve patients with no change in body fat, matched for age, disease control and treatment, were studied as controls.

MEASUREMENTS

Body composition was assessed by bioelectrical impedance analysis. Subcutaneous (SAT) and visceral (VAT) compartments of total abdominal adipose tissue (TAT) were measured by computed tomography. Resting metabolic rate (RMR) was assessed by indirect calorimetry. Endocrine investigations included plasma thyroid hormones, cortisol, testosterone, oestradiol and 24-hour urinary free cortisol (UFC) and catecholamines.

RESULTS

Despite similar body mass index, the patients with body fat alterations showed significantly larger VAT and higher VAT:TAT ratio than controls (P = 0.002 and 0.0001, respectively). In these patients, RMR was significantly higher than estimated according to the Harris-Benedict formula (+ 19.7 +/- 11.6 %, P = 0.0001) and correlated with VAT (r = 0.58, P = 0.003) and 24-hour urinary output of catecholamines (r = 0.67, P = 0.002), that was significantly increased in comparison with controls (1737 +/- 1228 vs 476 +/- 292 nmol, P = 0.013). We also found a significant correlation between VAT and UFC (r = 0.41, P = 0.042) that was absent in controls, although levels of UFC were similar in the two groups.

CONCLUSIONS

Our data suggest that body fat redistribution may involve cortisol and catecholamine actions. While high release of catecholamines may enhance RMR through increased lipolysis, cortisol may promote central fat storage. These effects might be related both to persistent hormonal responses to stress becoming inappropriate while disease control improved and to an increased sensitivity of visceral adipose tissue to cortisol in affected patients.

Nutrition and immune function in human immunodeficiency virus infection

The triad of human immunodeficiency virus (HIV) infection, nutritional status and immune function are intimately related, each factor having effects on the others. The dominant effect in this three-way relationship is the effect of HIV infection on nutritional status, an effect which, until the advent of potent anti-retroviral drugs, has been manifest primarily as wasting. Recently, more complex metabolic abnormalities have become apparent, particularly fat redistribution syndromes, hyperlipidaemia and hypercholesterolaemia. For the converse effect, the effect of nutritional state on HIV disease progression, there is good evidence that clinical outcome is poorer in individuals with compromised nutrition. However, the beneficial effects of nutritional support have been more difficult to demonstrate. For macronutrients, effective macronutrient supply improves survival in severely-malnourished individuals and may have beneficial effects in less-severely-affected individuals. Micronutrient deficiencies appear to be involved in modifying clinical HIV disease and may also be associated with enhanced mother-to-child transmission of virus, particularly in developing countries. Intervention trials in this setting are currently under way. In conclusion, the interaction of HIV infection and nutrition is of great importance not just because of the major impact that HIV infection has on nutritional state, but also because strategies to improve nutritional status, both quantitatively and qualitatively, may have a beneficial effect on the clinical and immunological course of the disease.

Elevated resting energy expenditure among HIV-seropositive persons receiving highly active antiretroviral therapy

OBJECTIVES

To ascertain the relationships between resting energy expenditure (REE), HIV RNA in plasma, and highly active antiretroviral therapy (HAART).

DESIGN

Cross-sectional analysis using data of a large cohort study of nutrition in relation to HIV disease.

METHODS

HIV RNA in plasma, REE, fat-free mass (FFM), and medication regimens were assessed at 530 visits among 372 participants in a cohort study of HIV-seropositive men and women.

RESULTS

HIV RNA in plasma was directly correlated with REE. After adjustment for FFM, age, CD4 cell count and HAART use, there was an increase in REE of 90 kJ/day per log10 copies/ml increase in HIV RNA [95% confidence interval (CI) 16-164; P = 0.02). HAART use had an independent effect on REE. In patients reporting HAART use, adjusted REE was 339 kJ/day higher than in those not reporting HAART use (95% CI 177-501; P = 0.0001).

CONCLUSIONS

Viral load and HAART appear to exert independent effects on REE. Although HAART may decrease metabolic rate by lowering viral burden, it appears to increase metabolic demands through some mechanism(s) independent of its effect on viral burden. This may result in elevated REE despite control of viral replication.

Malnutrition in tuberculosis

Tuberculosis has a dramatic effect on nutritional state and this has been borne out in all the studies that have investigated body composition in affected patients. I have included some of the key studies in this review; those I have not cited generally reach the same conclusions. Such malnutrition undoubtedly contributes to the morbidity of the disease and may also contribute to mortality, particularly in resource-poor settings where nutritional state, even in the "healthy," may be parlous. The extent to which such malnutrition also contributes to pathology remains unclear. Certainly, in other models, nutritional depletion has a major impact on immune function (Chandra, 1997) and depression of lymphocyte function cannot be a desirable commodity in an individual fighting invasive mycobacterial infection. Considering the reverse relationship, there is good evidence, both at the population level and at the clinical level, for the effect of primary malnutrition on tuberculosis, both to increase frequency of occurrence and to exacerbate clinical manifestations. It has not been possible to explore this relationship within the context of this paper but it is clearly an important aspect of the bi-directional relationship between tuberculosis and malnutrition. There is still more to be understood about the pathophysiology of the wasting seen in chronic infections such as tuberculosis but it is clear that, in addition to good anti-tuberculous therapy, such patients need a good supply of nutrition during the treatment/recovery phase. In the developed world, this may include medical measures to achieve nutritional support whereas in resource-poor settings, nutritional intake may have more to do with equitable resource distribution and community involvement in health care.

Childhood leukaemia: a model of pre-obesity

The prevalence of obesity in children, as in adults, is increasing dramatically. The extent to which this is due to reduced energy expenditure, increased energy intake, or both, is unclear at present. This in part reflects the limitations of existing models of the pre-obese state. In childhood acute lymphoblastic leukaemia (ALL), patients typically gain weight excessively during and after 2 years of therapy, and are at high risk of becoming obese. Previous studies have failed to identify the cause of obesity in these patients. We have tested the hypothesis that excess weight gain in ALL is due to reduced total energy expenditure (TEE), measured using the doubly-labelled water method, and have identified risk factors for excess weight gain in ALL. Pre-obese children with ALL in the dynamic phase of weight gain are less physically active than their peers, with a reduced TEE of approximately 1.2 (95% CI 0.2, 2.2) MJ/d. While other factors might contribute to excess weight gain, lifestyle (i.e. reduced habitual physical activity) plays a central role in ALL. Several considerations suggest that ALL might be a useful model of the pre-obese state: lifestyle is critical to development of obesity in ALL; ALL is relatively common; approximately 70% of patients survive; patients are readily accessible during the 2 years of therapy and beyond.

Tuberculosis, human immunodeficiency virus infection, and malnutrition in Burundi

In order to compare the nutritional status of tuberculosis (TB) patients who were human immunodeficiency virus (HIV)-seropositive with those who were seronegative, we carried out a cross-sectional anthropometric and biochemical assessment, together with bioelectrical impedance analysis (BIA) of the nutritional status of TB patients hospitalized in the Department of Internal Medicine, Bujumbura University Hospital, Burundi, East Africa. Of the 65 TB patients (33 pulmonary, 6 extrapulmonary, and 26 disseminated TB), 50 (76.9%) were HIV-seropositive (HIV+). When assessed according to anthropometric, BIA, and biochemical variables, HIV+ TB patients had more pronounced malnutrition than HIV- patients. Similar results were obtained when the comparison was restricted to patients with only pulmonary TB: HIV+ patients were more malnourished than HIV- patients. The results according to anthropometric measurements were: weight loss (13.5% of HIV- patients versus 26.4% of HIV+ patients, P = 0.005), body mass index (18.6 versus 15.1, P = 0.003), fat free mass (FFM) (13.9 versus 11.9, P < 0.01), and body fat (BF) (4.55 versus 3.71, P = 0.03) expressed per unit height2. BIA showed that the difference in FFM between HIV- and HIV+ TB pulmonary patients was mostly due to a decrease in body cellular mass. Measurements of albumin, prealbumin, and transferrin showed a marked decrease in all three markers in HIV+ TB pulmonary patients. The nutritional status of HIV+ patients with disseminated versus pulmonary TB was similar. The nutritional status of HIV+ TB patients is far worse than that of HIV- TB patients. In such patients, anthropometry underestimates the degree of malnutrition because it does not account for the water component of FFM. Nutritional status should be assessed and nutritional intervention should be provided in an attempt to improve the prognosis of TB patients, especially those who are infected by HIV.

Impact of tuberculosis on the body composition of HIV-infected men in Brazil

OBJECTIVE

Tuberculosis (TB) is the commonest HIV-related opportunistic infection in many developing countries and is thought to be a frequent underlying cause of HIV-associated wasting. We have used reference water dilution methods to examine the body composition changes associated with TB and to assess the severity and pattern of wasting.

METHODS

The study was conducted at a charitable support house for poor and homeless HIV-infected people in Rio de Janeiro, Brazil. Male patients who were HIV-positive and receiving treatment for active TB (HIVTB+) and HIV-infected controls without TB (HIVTB-) were studied. Total body water (TBW) and extracellular water (ECW) were measured by giving oral doses of deuterium oxide and sodium bromide, respectively, and determining enrichment in plasma after 4 hours. Intracellular water (ICW), body cell mass (BCM), lean body mass (LBM) and fat mass were calculated from these parameters using standard equations.

RESULTS

HIVTB+ (n = 11) and HIVTB- (n = 12) groups were similar in age, height, CD4 count and HIV risk factors. HIVTB+ men had significantly lower mean ICW (13.2 versus 16.6 kg; p = .02) and BCM (18.4 versus 23.0 kg; p = .02), a relative expansion of ECW (35.0 versus 30.0 L/kg body weight; p = .04), and small and nonsignificant reductions in total body weight (58.0 versus 62.1 kg; p = .26), LBM (45.5 versus 47.7 kg; p = .33) and fat mass (12.5 versus 14.4 kg; p = .51) compared with HIVTB- controls. BCM in the HIVTB+ group was similar to reference values for severe malnutrition. The relative depletion of BCM appeared excessive in comparison with reference values for uncomplicated starvation.

CONCLUSION

The nutritional status of HIVTB+ patients was significantly worse than HIVTB- patients. Body weight and LBM underestimated the nutritional deficit, and measurement of BCM is therefore necessary to appreciate the extent of malnutrition in such patients. Malnutrition in HIVTB+ patients is severe and may therefore contribute to decreased survival. Hypermetabolism appears to play a role in the wasting process in patients coinfected with HIV and TB.

Megestrol acetate: promises and pitfalls

Recent reports suggest that effective antiretroviral therapy, resulting in a plasma HIV load that has been reduced to undetectable levels, may itself prevent HIV- and opportunistic infection-associated weight loss and lead to substantial weight gain. Although these data are encouraging, it is clear that a significant proportion of patients will require, in addition, specific treatment for HIV-associated wasting. Megestrol acetate, in the dosage range of 400 to 800 mg/day, is a useful appetite stimulant for the prevention and treatment of HIV-associated wasting, particularly in women. Patients need to be advised of possible adverse effects and monitored closely. Megestrol acetate stimulates weight gain mostly through an increase in body fat and is therefore most effective in combination with a muscle-building exercise program, where appropriate, and an anabolic agent (steroid or growth hormone) to maintain or increase lean body mass.

Infections in adults undergoing unrelated donor bone marrow transplantation

This study retrospectively reviews infections over a 7-year period in 60 consecutive adults (median age 25 years) undergoing their first unrelated donor bone marrow transplant (UD-BMT). T-cell depletion was employed in 93%. More than half the patients had one or more severe, potentially life-threatening, infections. There was a high incidence of invasive fungal infections (Aspergillus 17, Candida four), despite the use of itraconazole or amphotericin prophylaxis. Ten Aspergillus infections occurred beyond 100 d. Two patients (11%) with invasive aspergillosis survived. Clustering of infections was noted, with invasive fungal infections significantly associated with bacteraemias (OR 3.73, P=0.06) and multiple viral infections (OR 4.25, P=0.05). There were 21 severe viral infections in 16 patients, with CMV disease occurring in four patients only; viral pneumonitis was predominantly due to 'community respiratory' viruses. Most early bacteraemias (68%) were due to Gram-positive organisms. The majority of episodes of Gram-negative sepsis were caused by non-fastidious non-fermentative bacteria, such as Pseudomonas spp. and Acinetobacter spp., historically regarded as organisms of low pathogenicity. In patients with successful engraftment and minimal graft-versus-host disease, late infections suggestive of continued immune dysfunction (shingles, recurrent lower respiratory infections, Salmonella enteritis and extensive warts) were common.

Relative influences of sex, race, environment, and HIV infection on body composition in adults

BACKGROUND

The factors that control body composition in disease are uncertain.

OBJECTIVE

We planned to compare the relative influences of HIV infection, sex, race, and environment on body composition.

METHODS

We analyzed results of body composition studies performed by bioelectrical impedance analysis in 1415 adults from 2 cohorts: white and African American men and women from the United States, and African men and women (279 HIV-infected and 1136 control). The effects of sex and HIV infection on weight, body cell mass, and fat-free mass were analyzed by using both unadjusted and age-, weight-, and height-adjusted data.

RESULTS

Control men weighed more and had more body cell mass and fat-free mass than did control women, although control women had more fat. The strongest correlates with body composition were height and weight, followed by sex. HIV infection, age, environment, and race. Control men and women weighed more and had more body cell mass, fat-free mass, and fat than did HIV-infected men. However, differences in body composition between HIV-infected and control groups were strongly influenced by sex. Of the differences in weight between HIV-infected and uninfected subjects, fat-free mass accounted for 51% in men but only 18% in women, in whom the remainder was fat. Sex effects were similar in African and American groups.

CONCLUSIONS

Sex has a marked effect on the changes in body composition during HIV infection, with women losing disproportionately more fat than men. Sex-related differences in body composition were narrower in the HIV-infected groups. Race and environment had smaller effects than sex and HIV infection.

Short-term progressive resistance training increases strength and lean body mass in adults infected with human immunodeficiency virus

BACKGROUND

To assess the efficacy of progressive resistance training (PRT) in increasing strength and lean body mass (LBM) in HIV-infected adults.

METHODS

Twenty-five adults with HIV infection were trained using a highly intensive PRT regimen for 8 weeks, followed by an additional 8 weeks of observation under ad libitum physical activity conditions.

RESULTS

Twenty-four of the 25 patients completed the first phase of the study. They had significant increases in strength on all four exercises tested (P < 0.0001), and an increase in LBM of 1.75 +/- 1.94 kg (mean +/- SD, P < 0.0002), with a concomitant decline in fat of 0.92 +/- 2.22 kg (P < 0.05), and no significant change in weight or bone mineral content. Twenty-one of the patients returned for follow-up 8 weeks after completing the PRT. Compared with their baseline values, their mean lean mass remained 1.40 +/- 1.8 kg higher (P < 0.003). Among those who continued to train to some extent, lean mass increased by a mean of 1.1 +/- 1.6 kg (n = 9, P < 0.05 versus end of PRT), whereas those who did no further training showed an increase in lean mass of 0.28 +/- 1.4 kg (n = 12, P = NS versus end of PRT). The difference between the two groups was not, however, significant (P = 0.25). Among six patients with AIDS wasting, the increase in LBM was larger than among non-wasted patients (2.8 versus 1.4 kg, P < 0.06), and there was an increase in both weight (+3.9 versus -0.2 kg, P < 0.002) and fat mass (+ 0.95 versus -1.5 kg, P < 0.002) at 8 weeks, which persisted at 16 weeks (weight: +4.0 versus -1.6 kg, P < 0.0002; fat: +1.6 versus -1.9 kg, P < 0.01).

CONCLUSION

This preliminary study suggests that short-term, high intensity PRT can significantly increase LBM and strength in HIV infection, and may be used as an alternative or adjunct to pharmacological anabolic treatments in this disease.

The effect of inactivity on dietary intake and energy homeostasis

Reduced physical activity commonly occurs in patients with disease or chronic disabilities, in the elderly, and in certain patients with obesity. Surprisingly, information on the effect of inactivity on energy homeostasis is scarce and often difficult to interpret. In models of reduced physical activity, such as space flights, bed-rest and confinement, subjects frequently lose weight (< 5%), predominantly in the form of fat-free mass. In some cases this is compensated by an increase in fat mass, which means that changes in weight are poor indicators of energy balance. The extent to which spontaneous reduction in energy intake (in most studies energy intake is fixed) compensates or overcompensates for the reduction in energy expenditure (mainly physical activity and to a small extent in BMR, typically < 6%) is largely underexamined. Preliminary observations suggesting that there is a preferential selection of low-energy-dense foods (low in fat) require confirmation under carefully controlled experimental conditions. It is concluded that a comprehensive and systematic evaluation is needed to address the effects and relevance of various degrees of physical inactivity to energy homeostasis, in relation to disease and space medicine.

The pathophysiology of wasting in the elderly

Aging is associated with changes in body composition and energy and protein metabolism that are due both to the direct effects of aging and to the effect of age-related diseases. We have recently differentiated these changes under three categories: wasting, cachexia, and sarcopenia. We have defined wasting as unintentional loss of weight, including both fat and fat-free compartments. Experience in the HIV epidemic suggests that wasting is driven largely by inadequate dietary intake. Cachexia, on the other hand, refers to loss of fat-free mass, and especially body cell mass, but with little or no weight loss. The metabolic hallmarks of cachexia are hypermetabolism and hypercatabolism, driven by inflammatory cytokine-mediated acute phase responses. Finally, sarcopenia refers to loss of muscle mass specifically, and seems to be an intrinsic age-related condition. In the elderly, wasting as defined here is at the extreme end of the spectrum, but generally develops in the setting of pre-existing sarcopenia and cachexia. The challenges before us now are to better define these conditions, establish guidelines for their recognition, and develop better methods for intervening when appropriate.

Wasting in HIV infection and AIDS

AIDS wasting is not characterized by a single pathophysiological process but by a variety of processes that operate at different times. Acute wasting tends to be associated with secondary infections; chronic wasting is associated with gastrointestinal disease. Although resting energy expenditure is increased, total energy expenditure is reduced in individuals who are losing weight and it is usually reduced intake that commonly drives wasting. However, reduced intake is not an adequate explanation for the metabolic abnormalities that are seen in HIV infection. In particular, protein metabolism and lipid metabolism are abnormal, possibly representing inappropriate utilization of substrates. The response to nutrition may be impaired, particularly in terms of accrual of lean tissue but nutritional support may prolong survival. The impact of protease inhibitors on wasting in HIV infection is yet to be fully ascertained but despite antiviral therapy it seems that wasting is likely to remain a problem at least in some patients.

Metabolic aspects of HIV: associated wasting

Despite recent progress in the treatment of human immunodeficiency virus (HIV) infection, wasting syndrome (WS) is now one of the major aspects of acquired immunodeficiency syndrome (AIDS). Malnutrition in HIV infected patients is characterised by a predominant loss of body cell mass (BCM), the amount of functional protoplasm in non-adipose tissue. This loss of BCM is correlated with a higher risk of AIDS events and a greater risk of mortality. If anorexia plays a major role in the development of the WS, some abnormalities in the metabolism drive the predominant loss of BCM. In the stable state, the resting energy expenditure (REE) is increased by about 10%. The REE is significantly correlated with the whole body protein turn over as measured by C13 leucine. This particular and only metabolic situation is associated with an increased insulin sensitivity and a high level in de novo hepatic lipogenesis. During periods of secondary infections, patients had a striking average weight loss, resulting from the combination of anorexia and dramatic elevated REE.

Organization of the human myostatin gene and expression in healthy men and HIV-infected men with muscle wasting

Myostatin, a member of the transforming growth factor-beta superfamily, is a genetic determinant of skeletal muscle growth. Mice and cattle with inactivating mutations of myostatin have marked muscle hypertrophy. However, it is not known whether myostatin regulates skeletal muscle growth in adult men and whether increased myostatin expression contributes to wasting in chronic illness. We examined the hypothesis that myostatin expression correlates inversely with fat-free mass in humans and that increased expression of the myostatin gene is associated with weight loss in men with AIDS wasting syndrome. We therefore cloned the human myostatin gene and cDNA and examined the gene's expression in the skeletal muscle and serum of healthy and HIV-infected men. The myostatin gene comprises three exons and two introns, maps to chromosomal region 2q33.2, has three putative transcription initiation sites, and is transcribed as a 3.1-kb mRNA species that encodes a 375-aa precursor protein. Myostatin is expressed uniquely in the human skeletal muscle as a 26-kDa mature glycoprotein (myostatin-immunoreactive protein) and secreted into the plasma. Myostatin immunoreactivity is detectable in human skeletal muscle in both type 1 and 2 fibers. The serum and intramuscular concentrations of myostatin-immunoreactive protein are increased in HIV-infected men with weight loss compared with healthy men and correlate inversely with fat-free mass index. These data support the hypothesis that myostatin is an attenuator of skeletal muscle growth in adult men and contributes to muscle wasting in HIV-infected men.

Fatigue in HIV illness: relationship to depression, physical limitations, and disability

OBJECTIVE

This study was conducted to investigate the prevalence of clinical fatigue reported by gay/bisexual men at all HIV illness stages, and whether fatigue, while associated with depression, independently contributes to limitations in physical function and disability.

METHOD

HIV- men, HIV+ men with CD4 counts >500, HIV+ men with CD4 counts 200 to 500, and men with AIDS were compared on prevalence of clinical fatigue, as defined by a standardized instrument. Among HIV+ men, the relationships among fatigue, depressed mood, major depressive disorder, HIV illness markers (including CD4 count and HIV RNA viral load), physical limitations, and disability were assessed at baseline and after 1 year.

RESULTS

The prevalence of clinical fatigue in men with CD4 counts <500 was 14%, significantly higher than HIV- men and HIV+ men with CD4 counts >500. However, fatigue was not directly correlated with CD4 count or HIV RNA. Fatigue was a chronic symptom that was associated with depressed mood, major depressive disorder, physical limitations, and disability. After 1 year, an increase in depressive symptoms predicted a small amount of variance in fatigue; however, depressive symptoms were not associated with physical limitations or disability after controlling for fatigue.

CONCLUSION

Fatigue is a chronic symptom that is more prevalent in advanced HIV illness, and which, although associated with depression, does not seem to be merely a symptom of depression. Because fatigue contributes independently to physical limitations and disability, it should be assessed and treated.

Role of cytokines in AIDS wasting

There is now a large literature implicating cytokines in the development of wasting and cachexia commonly observed in a variety of pathophysiologic conditions. In the acquired immunodeficiency syndrome (AIDS), cytokines elicited by primary and secondary infections seem to exert subtle and sustained effects on behavioral, hormonal, and metabolic axes, and their combined effects on appetite and metabolism have been postulated to drive wasting. However, correlations of increased blood levels of a particular cytokine with wasting in AIDS have not been consistent observations, perhaps because cytokines act principally as paracrine and autocrine hormones, as well as indirectly by activating other systems. A better understanding of the mechanisms underlying the catabolic effects of cytokines in clearly needed if more efficacious strategies are to be developed for the prevention and treatment of wasting in AIDS. In this review we first examine the interacting factors contributing to the AIDS wasting syndrome. We then analyze the complex and overlapping role of cytokines in the pathophysiology of this condition, and put forward a number of hypotheses to explain some of the most important features of this syndrome.

Effect of malabsorption on nutritional status and resting energy expenditure in HIV-infected patients

OBJECTIVE

To assess the influence of malabsorption on nutritional status and energy expenditure in patients at different stages of HIV infection.

DESIGN AND METHODS

Fifty HIV patients were classified into three groups: Group 1, HIV asymptomatic patients (n=17); Group 2, AIDS without opportunistic infection (n=16); Group 3, AIDS patients with active infection (n=17). Clinically-healthy subjects (n=19) were used as controls. Parameters measured were: anthropometry, body composition by tetrapolar bioelectrical impedance; resting energy expenditure (REE) by open-circuit indirect calorimetry; malabsoption by D-xylose absorption and triolein breath tests.

RESULTS

Malabsorption (defined as abnormality of xylose and/or fat absorption test) was found in 34 (68%) of patients: 9 (53%) Group 1; 11 (69%) Group 2; 14 (82%) Group 3. Twenty-seven (54%) had sugar malabsorption and 21 (42%) fat malabsorption. A significant relationship was observed between malabsorption and weight loss. REE measured was significantly lower in malabsorptive patients than in non-malabsorptive patients and controls (6006.3+/-846.5 versus 6443.4 + 985.5 versus 6802.1+/-862.7 kJ/day, respectively; P < 0.05). The REE adjusted for fat-free mass was lower in malabsorptive than in non-malabsorptive patients and slightly higher than in controls, although the differences were not statistically significant.

CONCLUSIONS

The results suggest that malabsorption is a frequent feature in HIV infection and is related to the HIV-related weight loss. Hypermetabolism is not a constant phenomenon in HIV infection since, in the presence of malabsorption, our patients show an appropriate metabolic response with a compensatory decrease in REE.

Resting energy expenditure and body composition in children with HIV infection

The purpose of this study was to determine whether alterations in body composition, resting energy expenditure (REE), and dietary energy intake are associated with growth retardation in HIV-positive children. Body composition (deuterium oxide dilution, skinfold measurements), REE (indirect calorimetry), and energy intake (24-hour weighed food intake) were evaluated in three groups: HIV-positive with growth retardation (HIV+Gr), HIV-positive with normal growth (HIV+); and HIV-uninfected with normal growth (HIV-). Children were between 2 and 11 years of age, afebrile, and free from acute infection. Forty-two children (13 HIV+Gr, 19 HIV+, 10 HIV-) were studied. Lean body mass was significantly reduced in HIV+Gr compared with HIV- (p < .05), and fat mass was significantly reduced in HIV+Gr and HIV+ compared with HIV- (p < .05). The percentages of lean and fat mass were not significantly different between groups, suggesting that differences in lean and fat mass were proportional to differences in body size. Consistent with reduced lean body mass, mean REE was significantly lower in HIV+Gr compared with HIV- (p < .05). Differences in mean REE/kg of body weight or lean body mass between groups were not statistically significant. A significant negative correlation was found between REE (kcal/kg/day) and weight-for-age (p = .04), and a trend with height-for-age Z-score (p = .07). Mean energy intake was not significantly different between groups. This study suggests that lean and fat mass are proportionately reduced in HIV-positive children with growth retardation. Further studies are necessary to delineate the relationship between energy balance and growth in children with HIV infection.

Effect of indinavir on HIV-related wasting

OBJECTIVE

To study the effect of the protease inhibitor indinavir on body weight and body composition of subjects with HIV-related wasting.

DESIGN

Prospective measurement of body weight in patients who had wasting and were treated with indinavir. A subgroup of 16 representative patients also underwent a metabolic study that included measurements of body composition (skinfolds and bioelectrical impedance) and food intake. Seven from this subgroup who did not have chronic diarrhoea also underwent indirect calorimetry for measurement of resting energy expenditure; the nine patients with wasting and chronic diarrhoea had measurements of faecal losses and intestinal permeability using the lactulose-mannitol test.

SETTING

A tertiary care university hospital.

PATIENTS

Two hundred and fourteen HIV-infected patients with wasting (less than 95% of usual body weight) had their body weight measured at day 0; 186 patients had a second body weight measurement within the first 100 days of treatment, and 160 patients were weighed a third time, at a median of 176 days.

RESULTS

Body weight increased significantly (P < 0.0001) during treatment, whatever the degree of weight loss at baseline. After a median of 176 days on treatment, body weight had increased in 119 out of the 160 patients followed (74.4%; mean weight gain, 6.3+/-SD 3.8 kg; range, 1-18 kg), had not changed in 13 (8.1%) and had fallen in 28 (17.5%; mean weight loss, 4.2+/-3.0 kg; range, 1-12 kg), relative to baseline. Overall, 119 out of the 214 patients (55.6%) from the initial population gained weight. Fat mass, fat-free mass and body cell mass increased significantly in the 16 patients who underwent metabolic studies, together with energy, protein and lipid intake. In the patients with chronic diarrhoea, intestinal permeability improved but there was no change in intestinal losses. In patients who had wasting but not chronic diarrhoea, resting energy expenditure did not change significantly. Body weight changes correlated with changes in the CD4+ cell count (r = 0.882; P = 0.00001) and, to a lesser extent, with changes in the viral load (r = -0.466; P = 0.047).

CONCLUSION

Indinavir significantly improved the nutritional status of these patients with HIV-related wasting.

Reduced energy expenditure in preobese children treated for acute lymphoblastic leukemia

Children with acute lymphoblastic leukaemia (ALL) typically gain weight at excessive rates during and after therapy, and a high proportion of young adult survivors are obese. Previous studies have failed to identify the abnormalities in energy balance that predispose these children to obesity. The aim of this study was to determine the cause of excess weight gain in children treated for ALL by testing the hypothesis that energy expenditure is reduced in these patients. Twenty children [9 boys, 11 girls; mean age 10.9 (3.2) y] treated for ALL who had shown excess weight gain, but were not obese [mean body mass index SD score 0.70 (1.04)], were closely and individually matched with 20 healthy control children [9 boys, 11 girls; mean age 10.7 (3.0) y; mean body mass index SD score 0.27 (0.91)]. In each child we measured total energy expenditure by doubly-labeled water method, resting energy expenditure, energy expended on habitual physical activity, and energy intake. Total energy expenditure was significantly higher in control subjects than in patients: mean paired difference 1185 kJ/d (282 kcal/d), 95% confidence interval (CI) 218-2152. This difference was largely due to reduced energy expended on habitual physical activity in the patients. Resting energy expenditure was lower in the patients: mean paired difference 321 kJ/d (76 kcal/d), 95% CI 100-541. Energy intake was also lower in the patients: mean paired difference 1001 kJ/d (238 kcal/d), 95% CI 93-1909. Children treated for ALL are predisposed to excess weight gain, and subsequently obesity, by reduced total energy expenditure secondary to reduced habitual physical activity. Prevention of obesity in ALL should focus on modest increases in habitual physical activity, modest restriction of dietary intake, and monitoring of excess weight gain.

Factors of weight loss in patients with HIV and chronic diarrhea

Weight loss is significant in patients with HIV and chronic diarrhea. The aim of our study was to test for the links between weight loss, the level of food intake, and the severity of diarrhea and nutrient malabsorption. One hundred and sixteen patients with HIV and chronic diarrhea underwent a standardized gastrointestinal and nutritional evaluation, which included a questionnaire on diarrhea, a prospective estimation of food intake, a measurement of blood parameters and fecal lipid and nitrogen outputs, a stool examination for bacteria and parasites, and upper and lower digestive tract endoscopy. Diarrhea resulted from an infection by Cryptosporidia, Microsporida, or other pathogens in 22%, 20%, and 13% of the patients, respectively. Diarrhea appeared idiopathic in 45% of the patients. A significant negative correlation existed between the severity of weight loss and the levels of nutrient intake (p < .005), and a significant positive correlation between the severity of weight loss and stool frequency (p < .01). Multiple linear regression identified low caloric intake and high stool frequency as predictive of weight loss. No significant correlation was found between weight loss and the parameters of malabsorption, either by bivariate study or multiple regression. These results suggest that, in patients with HIV and chronic diarrhea, the degree of wasting is significantly related to the levels of dietary intake and the clinical severity of diarrhea, but not to the extent of nutrient malabsorption.

HIV infection and malnutrition

Weight loss, anorexia, metabolic disorder and malabsorption are leading symptoms of HIV infection. Recent data help us to understand wasting as being intrinsically linked to immunodysregulation and enteropathy. In therapy, the role played by anabolic steroids and growth hormone has been newly defined. The new antiviral drugs may efficiently prevent clinical progression, including wasting. New metabolic side effects have, however, been encountered.

Testosterone as a treatment for fatigue in HIV+ men

This study assessed correlates of fatigue and the efficacy of testosterone therapy as a treatment for fatigue in men with symptomatic HIV and clinical hypogonadism. We conducted a 12-week open trial of testosterone for HIV+ men with clinical hypogonadism (low libido plus at least one of the associated symptoms of depressed mood, fatigue, and weight loss), CD4 count below 400 cells/cu.mm, and serum testosterone level below 500 ng/dl. 108 men entered the trial; 50% were nonwhite and 72% had an AIDS diagnosis. Baseline correlates of fatigue, as measured by the self-report Chalder Fatigue Scale (CFS), included elevated laboratory values (hematocrit, hemoglobin), lower overall physical functioning, greater psychological distress, and reduced quality of life. Sixty-six of 72 men who presented with fatigue completed the trial, with 52 (79%) rated as responders (much improved energy level) by the study doctor. Fatigue declined significantly among responders, but not nonresponders.

Comparison of total parenteral nutrition and an oral, semielemental diet on body composition, physical function, and nutrition-related costs in patients with malabsorption due to acquired immunodeficiency syndrome

BACKGROUND

The nutrition management of patients with malabsorption syndromes due to acquired immunodeficiency syndrome (AIDS) is problematic. The aim of this study was to compare the effects of total parenteral nutrition (TPN) and an oral, semielemental diet (SED) on body weight, body composition, quality of life, survival, and medical costs in AIDS patients with malabsorption.

METHODS

This was a prospective, randomized, open-label study performed in outpatients. Twenty-three AIDS subjects (TPN group, 12; SED group, 11) with cryptosporidiosis, microsporidiosis, or malabsorption of unknown cause were randomized and followed. Subjects were prescribed equivalent amounts of formulas of similar composition for 3 months. Monthly estimations of caloric intake, body weight, body composition by bioimpedance analysis, and quality of life were recorded. Nutritional variables were analyzed by repeated-measures analysis of covariance, with the baseline measure as the covariate. Nutrition-related medical costs, survival, and indices of absorptive and immune function were compared,

RESULTS

Subjects had lost an average of 1.5 and 1.0 kg body wt/mo for TPN and SED during the 6 months before study entry (p < not significant). The TPN group consumed more total calories than the SED group (p < .05). Weight change during therapy was significantly different from pretreatment in both groups (p < .01 for TPN, p = .023 for SED). The TPN group gained more weight than the SED group (p = .057) and significantly more fat (p = .02), but the changes in body cell mass were similar in the two groups. Changes in weight and body composition correlated with caloric intake but not the mode of feeding. The SED group scored significantly better than the TPN group on a physical functioning subscale of quality of life (p < .01). Survival was similar in the two groups. TPN therapy cost almost four times more than SED. Peripheral blood CD4+ lymphocyte numbers were unaffected by either therapy. Intestinal function was not affected by either therapy.

CONCLUSIONS

An oral SED may reverse weight loss and wasting in AIDS patients with malabsorption.

Levels of HIV RNA are quantitatively related to prior weight loss in HIV-associated wasting

Thirty-three patients referred to a wasting clinic were evaluated to assess whether levels of HIV RNA were related to the magnitude of prior weight loss. Their median RNA level was 46,887 gene copies/ml (range, <200-510,070 gene copies/ml) at the time of referral. Patients had lost 10.5 +/- 6.4 kg over 461 +/- 304 days. RNA levels were correlated with the absolute amount and percentage of weight lost as well as the difference in body mass index (BMI) at the prior maximal and minimal recorded weights (r = 0.7, 0.67, 0.69; p = .0001 for the comparisons). The magnitude of these changes increased across strata of HIV RNA levels (p < or = .004), previously defined as associated with increasing risk for disease progression. The other parameter that could be associated with weight loss was the CD4 lymphocyte count (r = -0.43; p = .01). Low levels of testosterone and measures of body cell mass, fat free mass, or fat mass within 6 weeks of the RNA level could not be related to weight loss, change in BMI, or RNA levels. Thirty-two of the patients had chronic, relentless weight loss; in 15 of these subjects, no apparent secondary opportunistic complications were associated with weight loss or gastrointestinal symptoms to impair energy intake. Levels of HIV replication appear to be causally related to the magnitude of weight loss in some patients with wasting.

HIV wasting syndrome: treatment update

OBJECTIVE

To review the pathophysiology and treatment of HIV wasting syndrome.

DATA SOURCES AND STUDY SELECTION

MEDLINE searches (January 1987-September 1997) of the English-language medical literature were conducted. Bibliographies were also selected during a manual review.

DATA SYNTHESIS

HIV-related weight loss, often referred to as HIV wasting syndrome, is a common manifestation of advanced HIV infection. Wasting in HIV involves the preferential loss of lean body mass with a paradoxical preservation of body fat. The etiology of wasting appears to be the result of many factors, which may include decreased caloric intake, malabsorption, alterations in energy expenditure and metabolism, cytokine effects, and endocrine dysfunction. Pharmacologic treatment options include appetite stimulants (e.g., dronabinol, megestrol acetate), cytokine inhibitors (e.g., thalidomide, cyproheptadine, ketotifen, pentoxifylline, fish oil, N-acetylcysteine), and anabolic agents (e.g., testosterone, nandrolone, oxandrolone, recombinant human growth hormone).

CONCLUSIONS

Wasting associated with HIV has a high morbidity and mortality rate if not adequately managed. Therapeutic strategies include appetite stimulants, cytokine inhibitors, and growth-promoting agents. Selection of the appropriate agent(s) depends on the underlying cause for weight loss, adverse effects, and cost of therapy.

Percutaneous endoscopic gastrostomy feeding in AIDS

Reduced energy intake is the most important reason for weight loss in advanced human immunodeficiency virus (HIV) infection. From January 1989 to August 1995 enteral feeding via a percutaneous endoscopic gastrostomy tube (PEG) was offered to all human immunodeficiency virus(HIV)/AIDS patients attending Fairfield Hospital, Melbourne who were unable to maintain 85% ideal body weight. A total of 71 patients received enteral feeding (1000-2000 kcal/day) for a median period of 161 days (range 4-644 days). Fifty-one (72%) patients gained 5.8 +/- 4.4kg (range 0.4-19.2 kg). Nine gained 10 kg or more. The median time to maximum weight was 74 days after PEG insertion. Those who gained weight had a longer median survival, but this difference was not statistically significant (210 vs 109 days, P = 0.07). The only predictor of weight gain was a CD4 count greater than 100/microL. Patients who gained weight reported improved quality of life and increased independence. However, early complications, especially wound infection, were common. Although these data have been gathered retrospectively, our experience suggests that enteral feeding can maintain or improve nutritional status and may improve quality of life in advanced HIV infection.