Glutathione, glutathione peroxidase, and selenium status in HIV-positive and HIV-negative adolescents and young adults.

BACKGROUND: Antioxidant nutrient deficiencies may hasten the progression of HIV disease by impairing antioxidant defenses. OBJECTIVE: The objective of the study was to determine whether HIV infection is associated with poor selenium status and low antioxidant protection by glutathione and glutathione peroxidase (GPX). DESIGN: In a cross-sectional study of 365 HIV-positive and HIV-negative adolescents and young adults, we examined the relation of plasma selenium, whole-blood glutathione, and whole-blood GPX to HIV status, disease severity, immune activation, and oxidative damage. RESULTS: Selenium deficiency (plasma selenium < 0.070 microg/mL) was not seen in any subjects, and plasma selenium in 244 HIV-positive subjects (0.120 +/- 0.0013 microg/mL) did not differ significantly (P = 0.071) from that in 121 HIV-negative subjects (0.125 +/- 0.0020 microg/mL) . However, multiple regression analysis after adjustment for covariates showed a significant (P = 0.002) negative association between HIV-associated immune activation (plasma neopterin) and plasma selenium concentrations. GPX activity was highest in HIV-positive subjects taking antiretroviral therapy (median: 14.2; 25th, 75th percentiles: 11.1, 18.7 U/mL; n = 130), intermediate in HIV-positive subjects not taking antiretroviral therapy (11.8; 9.4, 15.1 U/mL; n = 114), and lowest in HIV-negative subjects (10.6; 8.6, 12.7 U/mL; n = 121; P < 0.05 for all comparisons). GPX was also positively associated with malondialdehyde, a marker of oxidative damage. CONCLUSIONS: Subjects had adequate selenium status, although HIV-related immune activation was associated with lower plasma selenium concentrations. GPX activity appears to have been induced by the oxidative stress associated with HIV infection and use of antiretroviral therapy. Thus, young, well-nourished subjects can mount a compensatory antioxidant response to HIV infection.

Vitamin D status in adolescents and young adults with HIV infection.

BACKGROUND: Vitamin D status affects immune function and thus may affect the progress of HIV infection. OBJECTIVES: Our goals were to assess vitamin D intake and status in subjects with HIV infection and in matched control subjects and to determine whether HIV infection was associated with vitamin D insufficiency. DESIGN: Plasma 25-hydroxyvitamin D [25(OH)D] concentrations and vitamin D intake were measured in a cross-sectional study of members of the Reaching for Excellence in Adolescent Health (REACH) cohort. RESULTS: The subjects were aged 14-23 y; 74% were female, and 72% were black. Mean (+/-SE) vitamin D intake from food was 30% greater (P = 0.023) in HIV-positive subjects (295 +/- 18 IU/d; n = 237) than in HIV-negative subjects (227 +/- 26 IU/d; n = 121). The prevalence of vitamin D supplement use was 29% (104 of 358 subjects) and did not differ significantly by HIV status (P = 0.87). Mean plasma 25(OH)D did not differ significantly (P = 0.62) between the HIV-positive (20.3 +/- 1.1 nmol/L; n = 238) and HIV-negative (19.3 +/- 1.7 nmol/L; n = 121) subjects, nor was HIV status a significant predictor of plasma 25(OH)D when multiple regression analysis was used to adjust for other variables. The prevalence of vitamin D insufficiency [plasma 25(OH)D < or = 37.5 nmol/L] in the subjects was 87% (312 of 359 subjects). CONCLUSIONS: HIV infection did not influence vitamin D status. The prevalence of vitamin D insufficiency in both HIV-positive and HIV-negative REACH subjects was high, perhaps because these disadvantaged, largely urban youth have limited sun exposure.

Vitamins C and E in adolescents and young adults with HIV infection.

BACKGROUND: Oxidative stress during HIV infection may impair immune function, cause more rapid disease progression, and increase requirements for dietary antioxidants such as vitamins C and E. OBJECTIVES: The study had 2 principal objectives. The first was to ascertain whether HIV infection and immune activation were associated with lower plasma concentrations of ascorbate, urate, and alpha- and gamma-tocopherols and with total antioxidant status (TAS). The second objective was to ascertain whether these antioxidants were associated with protection against oxidative damage. DESIGN: This was a cross-sectional study involving 241 HIV-positive and 115 HIV-negative subjects aged 14-23 y. Subjects were primarily female (76%) and African American (70%), and 21% were Hispanic. RESULTS: Plasma ascorbate was significantly lower, but gamma-tocopherol and TAS were significantly higher in subjects with HIV infection when the analysis was adjusted for dietary intake and sex. Plasma alpha-tocopherol did not differ significantly by HIV status. Plasma gamma-tocopherol also was higher in subjects with oxidative damage than in those without such damage. More than 90% of subjects had adequate plasma concentrations for both ascorbate and alpha-tocopherol, although alpha-tocopherol concentrations were lower than expected on the basis of third National Health and Nutrition Examination Survey data. CONCLUSIONS: Low plasma ascorbate concentrations in HIV-positive subjects suggest that vitamin C requirements are significantly higher in those with HIV infection. Plasma tocopherol concentrations were not depressed by HIV infection and may be maintained by compensatory mechanisms such as the activity of alpha-tocopherol transfer protein.

HIV-infected US youth are at high risk of obesity and poor diet quality: a challenge for improving short- and long-term health outcomes.

OBJECTIVE: To examine the relationships among dietary quality, weight status, and human immunodeficiency virus (HIV) infection in US adolescents and young adults. DESIGN: This cross-sectional study was embedded in the Reaching for Excellence in Adolescent Care and Health cohort study of HIV-infected and HIV-uninfected, at-risk youth. Biochemical, clinical, and sociodemographic data were available. Dietary intake was collected using the Block Food Frequency Questionnaire and a modified Healthy Eating Index was calculated to measure diet quality. SUBJECTS/SETTING: Participants included 264 HIV-infected and 127 HIV-uninfected youth 13 to 23 years old (75.2% women, 67.3% African American/non-Hispanic, 20.5% Hispanic, 12.3% other) at 14 clinic sites. STATISTICAL ANALYSES PERFORMED: Determinants of obesity and the modified Healthy Eating Index were tested using logistic and generalized linear regression. RESULTS: About half (51.7%) of participants were overweight or obese. Obesity was positively associated with being a woman, living independently, watching television >or=3 hours per day, previous dieting, and being from the northeastern or southern United States. Youth who were HIV uninfected or HIV infected with CD4 + T cells >or=500 cells/microL had similar obesity rates; overweight (25%) and obesity (20%) was prevalent among women even with CD4 + T cells <200 cells/microL. The modified Healthy Eating Index score was 56.2+/-0.6, reflecting a diet needing improvement. HIV infection, watching television >or=3 hours/day, and being from the Chicago, IL, area were associated with a lower-quality diet. CONCLUSIONS: Obesity is a common nutrition problem for both HIV-infected and uninfected youth; however, HIV-infected youth are at increased risk of developing metabolic abnormalities. Culturally appropriate, client-focused nutrition education will help youth improve their diet and increase physical activity to reduce health consequences associated with both obesity and HIV infection.

US youths in the early stages of HIV disease have low intakes of some micronutrients important for optimal immune function.

OBJECTIVE: We examined the association between micronutrient intakes and human immunodeficiency virus (HIV) infection in youths who were at increased nutritional risk because of the demands of growth and disease as well as poor dietary habits. DESIGN: This was a cross-sectional study to collect dietary intake data using the Block Food Frequency Questionnaire (98.2). Anthropometric, biochemical, clinical, and sociodemographic data were available.Subjects/Setting Participants included 264 HIV-infected and 127 HIV-uninfected adolescents and young adults from the Reaching for Excellence in Adolescent Care and Health network, a multisite observational study on HIV progression. Statistical analyses CD4(+) T cells were stratified for HIV-infected youths: >/=500, 200 to 499, and <200 cells/microL. Micronutrient intakes were compared by presence of HIV infection, using two-sample Student's t tests. Categoric analyses used chi(2) test. Generalized linear regression determined predictors of vitamins A, C, and E; iron; and zinc intakes. RESULTS: Almost half (49.0%) of the HIV-infected participants had CD4(+) T cells >/=500 cells/microL. After controlling for other factors, HIV-infected participants with CD4(+) T cells >/=500 had decreased iron intake (P<.05) and tended to be associated with lower intakes of vitamins C and E (P<.10) compared with those with more advanced disease and HIV-uninfected youths. Among those youths with CD4(+) T cells between 200 and 499 cells/microL, a high anxiety score was associated with a sixfold increase in vitamin A intake as compared with those with a low score.Applications/conclusions Given the increased micronutrient requirements, nutrition counseling with HIV-infected youths should focus on early increase of intake of foods rich in micronutrients to improve growth, slow disease progression, and increase survival.

A preceptor focus group approach to evaluation of a dietetic internship.

Geographical dispersion of preceptors within dietetic internship programs creates educational challenges. Iowa State University's dietetic internship utilizes preceptors from more than 90 facilities statewide. Three preceptor focus groups were conducted to identify strengths and areas needing improvement in the internship, including preceptor and intern needs and expectations. Of the more than 90 preceptors representing medical nutrition therapy, foodservice management, and community nutrition, 36 were contacted and 18 preceptors participated, resulting in 5 to 7 participants per focus group. Emerging themes included effective feedback; preceptor networking; and communication between internship program/faculty, interns, and preceptors. Geographic isolation and minimal use of Internet-based resources may contribute to these themes. Whereas the majority of preceptors had access to the Internet, only 7 (38%) had accessed the Internet-based resources provided by the program. Preceptor suggestions can provide new perspectives for enhancing the learning environment. Regional workshops and e-mail list-serves can help facilitate communication and networking among preceptors.