Weight Loss and Wasting Remain Common Complications in Individuals Infected with Human Immunodeficiency Virus in the Era of Highly Active Antiretroviral Therapy

Weight loss and/or wasting were among the most frequently occurring AIDS-defining conditions in the era before the use of highly active antiretroviral therapy (HAART). The wasting syndrome accounted for ∼18% of the new diagnoses of AIDS in the early 1990s [1]. Since the advent of protease inhibitors in combination with other antiretroviral agents, many of the AIDS-defining, opportunistic illnesses have decreased in frequency [2]. It was assumed that more-effective treatment of HIV infection would also radically reduce the problem of weight loss in this population. However, data from studies that have addressed this issue have not clearly demonstrated that there is an association between suppression of HIV and either maintenance of nutritional status or the return of nutritional status to a normal level [3, 4]. In an attempt to resolve this issue, we have examined baseline and prospective data from a large cohort of HIV-infected individuals for the incidence of weight loss and wasting during a time when the majority of these patients were using HAART.

Subjects are HIV-positive men and women who are enrolled in a longitudinal study (Nutrition for Healthy Living) that began in 1995. The study participants undergo nutritional and health assessments at baseline and at study visits that occur every 6 months. During these assessments, data on weight, height, anthropometry, bioelectrical impedence analysis (BIA), intercurrent medical and medication history, and laboratory parameters of HIV infection, including CD4 cell count and HIV RNA, are collected. In addition, each month, data on current weight, change in medications, and health status were obtained during a telephone interview with each subject. The study was approved by the Human Investigation Review Committee (New England Medical Center, Boston, MA), and patients provided written informed consent.

Any individual who had a loss of >10% of body weight since the baseline visit or who had a body mass index that had fallen to <20 kg/m² since the last clinic visit was considered to have wasting. An additional definition of wasting was a loss of >5% of body weight during a 6-month period between clinic visits, with the loss sustained for ≥1 year. At study visits every 6 months, height and weight were measured on a calibrated scale by trained study personnel.

Height (to the nearest 0.1 cm) was determined by use of a stadiometer, and weight (to the nearest 0.1 kg) was determined by use of a standardized standing beam balance. Body composition was obtained by BIA, which was performed using a Quantum Hand Held Analyzer (RJL Systems, Clinton, MI).

The cohort has enrolled 633 participants; of these, 466 have sufficient follow-up data available for the purpose of defining wasting. Of the group for whom follow-up data were available, 27% were women, 38% were ethnic minorities, 41% had less than a high school education, 48% earned <$10,000 (US) per year, and 56% were living below the federal poverty level. The full spectrum of HIV infection was represented in the cohort: 30% of the participants had CD4 cell counts <200 cells/mm³, 46% had CD4 cell counts of 200–500 cells/mm³, and 24% had >500 cells/mm³. The cohort is fully described elsewhere [3; J. E. Forrester, D. Speigelman, M. Woods, T. A. Knox, J. M. Fauntleroy, and S. L. Gorbach, unpublished data].

Of the 633 individuals enrolled, 88 (13.9%) reported wasting at the time of their enrollment. These individuals with self-reported wasting at baseline are not included in further analysis.

Of the 466 individuals in the cohort, 84 (18%) had lost >10% of body weight since their initial (baseline) study visit (table 1). Ninety-nine patients (21%) lost >5% of their usual body weight in 6 months, and this weight loss was sustained for ≥1 year. Thirty-nine patients (8%) were found to have a body mass index <20 kg/m² since their last study visit. A total of 156 patients (33.6%) in the cohort met at least 1 of the criteria for wasting. (Some individuals have met more than 1 definition of wasting and are included in each individual group.)

View larger version:

• In this window
• In a new window

• Download as PowerPoint Slide

Table 1

Incidence of wasting in the 466 HIV-infected subjects in the Nutrition for Healthy Living cohort.

In a separate analysis of 497 patients in the cohort, a total of 289 patients (58% of the cohort; 221 males and 68 females) lost >1.5 kg between any 2 study visits made every 6 months (table 2). A cutoff of 1.5 kg was used to ensure that true weight loss, rather than routine scale variation, would be recorded. The mean weight loss in this group of patients was 4.0 kg; of this weight loss, a mean of 1.3 kg was fat-free mass and 2.7 kg was fat mass.

View larger version:

• In this window
• In a new window

• Download as PowerPoint Slide

Table 2

Weight loss in subjects in the Nutrition for Healthy Living cohort (n = 497).

Of the 633 enrollees in the entire cohort, 211 have never used HAART (33%), and 422 have used HAART at some point in time (table 3). Sixteen of the enrollees who have never used HAART (7.5%) reported wasting at the time of enrollment; an additional 37 (17%) do not have sufficient follow-up data to determine wasting. Of the remaining 158 individuals who have never used HAART, 41 (25.9%) met at least 1 of the definitions of wasting during the course of the study. Of the 422 individuals in the total cohort who have used HAART at some point in time, 72 (17.2%) reported wasting at the time of study entry, and 22 do not have sufficient follow-up data to determine wasting. Of the 328 remaining individuals, 95 (28.9%) met at least 1 of the definitions of wasting during the course of the study. Of the 64 individuals who were not taking HAART when they entered the study and who met at least 1 of the definitions of wasting during the course of the study, 31 (48.4%) met at least 1 of the definitions of wasting after HAART therapy was begun. It appears that the use of HAART has no influence on the development of wasting.

View larger version:

• In this window
• In a new window

• Download as PowerPoint Slide

Table 3

Findings on wasting and the use of highly active antiretroviral therapy (HAART) among 633 HIV-infected subjects in the Nutrition for Healthy Living cohort.

It has been presumed that the problem of weight loss or malnutrition in HIV-infected patients would be eliminated in the era of HAART. Studies that have examined this assumption have found conflicting results.

Studies performed by our group and others have attempted to examine the impact of HAART on the weight loss and body composition of patients who are infected with HIV, and they have found HAART to have varying levels of benefit [3, 4]. However, these studies have not attempted to address the incidence or prevalence of either weight loss or wasting in the HIV-infected population in the current clinical era.

The definition of wasting, developed by the Centers for Disease Control and Prevention (CDC) in 1987, required an involuntary weight loss of >10% of baseline body weight plus either diarrhea, fever, or weakness for >30 days [5]. Most investigators have dropped the comorbid conditions and have simply used weight loss >10% as the definition of HIV-associated wasting. In this CDC definition, “baseline weight” is not further defined, nor is any time frame for the weight loss specified. Some investigators are using a definition of wasting that requires a weight loss >5% in a 6-month period and that the weight loss be sustained. Wheeler et al. [6] have shown that this level of weight loss can predict mortality and infectious complications in individuals with AIDS. Reduction in a body mass index to <20 kg/m² in a 6-month period is also an index of wasting. Because of the current uncertainty as to which of these definitions should be the standard definition of wasting, we have presented data using all 3 criteria.

Nearly 14% of the individuals in our cohort reported wasting, according to the CDC definition (loss of >10% of usual body weight), at the time of enrollment. Although this is self-reported wasting, the prevalence of wasting in this group correlates well with the prevalence of wasting in the population with HIV as a whole [7]. More importantly, a substantial number of participants in the cohort continued to lose weight (58%) or met 1 of the definitions of HIV-associated wasting (33%) during the course of our study, at a time when HAART was in common use.

These data strongly suggest that weight loss and wasting continue to be common problems for individuals infected with HIV. In addition, these complications continue to occur in patients treated with HAART as well as in those for whom HAART has failed or those who cannot tolerate the HAART regimens.

• © 2000 by the Infectious Diseases Society of America