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Sherwood L Gorbach

Publications and source records attributed to Sherwood L Gorbach.

At least 19 recordsLinked to original sources
PubMed2006

Incidence of metabolic syndrome in a cohort of HIV-infected adults and prevalence relative to the US population (National Health and Nutrition Examination Survey).

BACKGROUND: Metabolic syndrome increases the risk of cardiovascular outcomes and type II diabetes. Most of the metabolic abnormalities defining metabolic syndrome are observed in HIV. OBJECTIVE: To determine the incidence and risk factors for metabolic syndrome in HIV-infected adults in the Nutrition for Healthy Living (NFHL) study (2000-2003) and prevalence relative to the findings of the National Health and Nutrition Examination Survey (NHANES) (1999-2002). METHODS: Metabolic syndrome is > or =3 of the following: hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hypertension, abdominal obesity, and high serum glucose. The baseline prevalence of metabolic syndrome in the NFHL study (n = 477) was compared to that in the NHANES (n = 1876), adjusted for age, race, gender, poverty, exercise, and diet. RESULTS: Almost one quarter of NFHL subjects had metabolic syndrome. Most with metabolic syndrome (77%) had low HDL and hypertriglyceridemia plus > or =1 additional abnormality. The prevalence of metabolic syndrome was significantly lower in HAART and non-HAART users compared with NHANES participants unadjusted for body mass index (BMI). After adjustment for BMI, it was no longer significant but the trend remained. The incidence of metabolic syndrome in the NFHL study was higher with increasing viral load, higher BMI, higher trunk-to-limb fat ratio, and Kaletra (lopinavir/ritonavir) or didanosine (ddI) use and lower among college-educated persons. CONCLUSIONS: Metabolic syndrome is mostly diagnosed through low HDL and high triglycerides in HIV. The risk of developing the syndrome is related to HIV, specific medications, and body fat.

Adult↗
PubMed2006

Risk of cardiovascular disease in a cohort of HIV-infected adults: a study using carotid intima-media thickness and coronary artery calcium score.

BACKGROUND: There is concern that human immunodeficiency virus (HIV) infection and the use of highly active antiretroviral therapy lead to accelerated atherosclerosis and increased risk of cardiovascular disease. We measured 2 surrogate markers of subclinical atherosclerosis, carotid intima-media thickness (c-IMT) and coronary artery calcium (CAC) scores, in HIV-infected adults. METHODS: A cross-sectional analysis of 242 men and 85 women with HIV infection was used. Carotid ultrasonography and coronary computed tomography were performed, and their associations with cardiovascular risk factors were examined. RESULTS: Among men, the mean (+/- standard deviation [SD]) common c-IMT was 0.62+/-0.2 mm, the mean (+/-SD) internal c-IMT was 0.76+/-0.5 mm, and 136 patients (56.1%) had detectable CAC. Among women, the mean (+/-SD) common c-IMT was 0.59+/-0.2 mm, the mean (+/-SD) internal c-IMT was 0.66+/-0.4 mm, and 40 patients (47.1%) had detectable CAC. Neither the c-IMT nor the CAC score differed by antiretroviral therapy class or individual medications for either sex. For men, age and waist circumference independently predicted common c-IMT; age, systolic blood pressure, and high-sensitivity C-reactive protein level independently predicted internal c-IMT; and age, apolipoprotein B level, and high-sensitivity C-reactive protein level independently predicted CAC score. For women, age and body mass index independently predicted common c-IMT; age independently predicted internal c-IMT; and age and glucose level independently predicted CAC score. CONCLUSIONS: Our participants had more abnormal surrogate markers than expected at a relatively young age, but those were not associated with use of highly active antiretroviral therapy or protease inhibitors. At present, the positive associations were primarily with traditional and novel cardiovascular risk factors. Some HIV-specific (not treatment-specific) factors were observed; they may become more evident with prolonged HIV infection and treatment.

Adult↗
PubMed2006

Update on Clostridium difficile.

The most dramatic change in the past several years has been the increased incidence and severity of Clostridium difficile colitis reported from multiple countries. A number of factors have likely contributed to this. One major event has been the emergence of a fluoroquinolone-resistant clone of C. difficile with enhanced virulence properties that is associated with epidemic disease. Also noteworthy is the apparently decreasing effectiveness of the first-line agent metronidazole in treating this disease. Aggressive treatment of severe C. difficile colitis requires a multifaceted approach, including: 1) cessation of antibiotics where possible; 2) oral vancomycin; 3) if an ileus exists, intravenous administration of metronidazole and possibly intracolonic administration of vancomycin; 4) intravenous immunoglobulin if response to therapy is not rapid, or if there are signs of sepsis; and 5) early surgical consultation. Although it is likely that intravenous immunoglobulin contains antibodies against C. difficile toxins, its benefit remains unproven in rigorous clinical trials. Efforts to actively or passively immunize patients at risk are being explored to prevent the increasing morbidity and mortality associated with this disease. However, defining exactly who is at risk for severe C. difficile-associated disease is complex, as cases are being reported in populations not previously believed to be vulnerable.

Journal Article↗
PubMed2006

Probiotics: their role in the treatment and prevention of disease.

A probiotic is a "live microbial food ingredients that, when ingested in sufficient quantities, exerts health benefits on the consumer". Probiotics exert their benefits through several mechanisms; they prevent colonization, cellular adhesion and invasion by pathogenic organisms, they have direct antimicrobial activity and they modulate the host immune response. The strongest evidence for the clinical effectiveness of probiotics has been in their use for the prevention of symptoms of lactose intolerance, treatment of acute diarrhea, attenuation of antibiotic-associated gastrointestinal side effects and the prevention and treatment of allergy manifestations. More research needs to be carried out to clarify conflicting findings on the use of probiotics for prevention of travelers' diarrhea, infections in children in daycare and dental caries, and elimination of nasal colonization with potentially pathogenic bacteria. Promising ongoing research is being conducted on the use of probiotics for the treatment of Clostridium difficile colitis, treatment of Helicobacter pylori infection, treatment of inflammatory bowel disease and prevention of relapse, treatment of irritable bowel syndrome, treatment of intestinal inflammation in cystic fibrosis patients, and prevention of necrotizing enterocolitis in premature infants. Finally, areas of future research include the use of probiotics for the treatment of rheumatoid arthritis, prevention of cancer and the treatment of graft-versus-host disease in bone marrow transplant recipients.

Gastrointestinal Diseases↗
PubMed2005

Insulin resistance in HIV-infected men and women in the nutrition for healthy living cohort.

OBJECTIVE: We evaluated insulin resistance (IR) in an HIV-infected cohort and compared our results with those of the National Health and Nutrition Examination Survey III (NHANES III). METHODS: Using a cross-sectional study design, we determined the Quantitative Insulin Sensitivity Check Index (QUICKI) in 378 nondiabetic participants in the Nutrition for Healthy Living (NFHL) study and evaluated the association of the QUICKI with demographic, socioeconomic, body composition, lipid, liver function, HIV-associated factors (CD4 cell count, viral load, highly active antiretroviral therapy type, and years infected), and injection drug use. The prevalence of IR (QUICKI <0.350) and the mean QUICKI were ascertained for nondiabetic persons aged 25 to 65 years in the NHANES III and compared with those in the NFHL study. RESULTS: Protease inhibitor (PI) highly active antiretroviral therapy (HAART) and nonnucleoside reverse transcriptase inhibitor (NNRTI) HAART were associated with worse IR in HIV-infected men. Greater waist circumference, triglycerides, age, and alanine aminotransferase were associated with worse IR, and higher high-density lipoprotein, low-density lipoprotein, and smoking were associated with less IR in the NFHL study; CD4 cell count, viral load, and years HIV infected were not associated with IR. There was no significant difference in the prevalence of IR in the NFHL study versus the NHANES III (51% vs. 47%; P = 0.27). NFHL participants were not more IR than NHANES III participants. CONCLUSIONS: IR in the NFHL study was quite common but not significantly different than in the NHANES III and was associated with similar factors as in the general population. PI HAART and NNRTI HAART were associated with worse IR in men.

Antiretroviral Therapy, Highly Active↗
PubMed2005

The effect of micronutrient supplementation on disease progression and death in simian immunodeficiency virus-infected juvenile male rhesus macaques.

BACKGROUND: We investigated the impact that micronutrient supplementation has on the progression of simian acquired immunodeficiency syndrome (SAIDS). METHODS: Twenty-four simian immunodeficiency virus-infected juvenile male rhesus macaques were randomized into 2 groups. One group was given certified chow, and the other group was given chow and a supplement that contained 2-3 times the estimated nutritional requirement of micronutrients. Virological, immunological, and body composition measurements were taken every 4 weeks for 120 weeks. RESULTS: There was no difference between groups in weight gain, body mass index (BMI), crown-heel length, waist circumference, total tissue mass, lean mass, bone mineral content, or bone mineral density. The rhesus macaques on the supplemented diet had a higher death rate (hazard ratio, 2.39; P<.001) than those on the nonsupplemented diet; death in both groups was associated with a higher viral load set point during the early phase of infection. Additionally, higher body weight, BMI, crown-rump length, and lower viral load set point were protective from death in both groups. CONCLUSIONS: Micronutrient supplementation did not significantly alter the progression of SAIDS with respect to changes in body composition and immunological characteristics. A significantly higher rate of death was observed in rhesus macaques on the supplemented diet.

Animals↗
PubMed2005

Protease inhibitor-based HAART, HDL, and CHD-risk in HIV-infected patients.

OBJECTIVE: To study the effects of HIV-infection and protease inhibitor (PI)-based highly active anti-retroviral therapy (HAART) on the lipid and high-density lipoprotein (HDL) subpopulation profile and to relate the changes to coronary heart disease (CHD)-risk. METHODS AND DESIGN: The lipid and HDL subpopulation profiles of HIV-positive subjects (n = 48) were studied prospectively by comparing pre- and post-PI-HAART data as well as cross-section by comparing the profiles to HIV-negative subjects with (n = 96) and without CHD (n = 96). RESULTS: HIV-infected HAART-naïve subjects had lower concentrations of low-density lipoprotein cholesterol (LDL-C) and HDL-C and higher concentration of triglycerides (TG) than healthy controls. After receiving PI-based HAART, LDL-C and TG concentrations increased, while HDL-C concentrations remained unchanged. The HDL subpopulation profiles of HAART-naïve HIV-positive patients were significantly different from those of healthy controls and were similar to those with CHD. Moreover, the HDL subpopulation profile changed unfavorably after PI-based HAART, marked with increased concentrations of the small, lipid-poor pre-beta-1 HDL (32% or 3.9 mg/dl; p < 0.001), and decreased concentration of the large, cholesterol-rich alpha-1 HDL (9% or 1 mg/dl ns). CONCLUSION: An already unfavorable lipid and HDL subpopulation profile of HIV-positive HAART-naïve subjects further deteriorated after receiving PI-based treatment, which may cause increased CHD-risk in these subjects.

Adult↗
PubMed2005

Differences in serum sex hormone and plasma lipid levels in Caucasian and African-American premenopausal women.

CONTEXT: Risk of coronary heart disease is higher in African-American than in Caucasian women. OBJECTIVE: The aim of this study was to evaluate the contribution of sex hormone levels, race, and measures of body fat to the variation in plasma lipid levels, a well-established risk factor for coronary heart disease. DESIGN: This was a cross-sectional study. SETTING: The study was conducted in the general community. STUDY PARTICIPANTS: Sixty Caucasian and 117 African-American premenopausal women participated. MAIN OUTCOME MEASURES: Body weight, body mass index (BMI), and waist to hip circumference ratio (WHR), as well as plasma lipid and serum sex hormone levels, were assessed. RESULTS: Relative to Caucasian women, African-American women had significantly higher mean BMI (23.92 +/- 3.87 vs. 26.99 +/- 5.87 kg/m2, respectively; P < 0.001), and WHR (0.733 +/- 0.052 vs. 0.757 +/- 0.068; P < 0.03). Also, plasma triglyceride (TG) levels were significantly lower in African-American women (81 +/- 61 vs. 55 +/- 24 mg/dl; P < 0.0001). Serum estrone sulfate (556 +/- 323 vs. 442 +/- 332 pg/ml, Caucasian vs. African-American; P < 0.001), estradiol (E2) (55.1 +/- 43.6 vs. 35.8 +/- 17.7 pg/ml; P < 0.0001), androstenedione (2.6 +/- 0.9 vs. 1.6 +/- 0.7 ng/ml; P < 0.0001), and testosterone (0.36 +/- 0.12 vs. 0.31 +/- 0.19 ng/ml; P < 0.002) levels were significantly lower in African-American women than in Caucasian women. After correction for the effects of age, BMI, and WHR, serum E2 levels were significantly and positively associated with plasma high-density lipoprotein cholesterol levels in all women, and serum estrone sulfate levels with plasma total cholesterol and TG levels in African-American women. CONCLUSIONS: Our results indicate that race is an important determinant of plasma TG and serum sex hormone levels, even after adjustment for differences in body size. A significant association between endogenous E2 and high-density lipoprotein cholesterol levels exists in premenopausal women, independent of their race.

Adolescent↗
PubMed2005

A comparison of the clinical and cost-effectiveness of 3 intervention strategies for AIDS wasting.

OBJECTIVE: To compare oxandrolone (OX) or strength training with nutrition alone (NA) for AIDS wasting. SUBJECTS: Fifty patients with AIDS; 47 completing the study. INTERVENTIONS: Randomization to (1) NA with placebo pills, (2) nutrition with 10 mg of OX administered orally twice a day, or (3) nutrition with progressive resistance training (PRT) for 12 weeks. MAIN OUTCOME MEASURES: Midthigh cross-sectional muscle area (CSMA), physical functioning (PF), costs, and cost-effectiveness in dollars/quality-adjusted life-years (dollars/QALYs). RESULTS: The OX and PRT subjects had increases in CSMA (7.0% +/- 2.5%, P = 0.01; 5.0% +/- 2.0%, P = 0.04, respectively), although these increases did not differ significantly from the NA arm (NA: 1.0% +/- 1.0%; OX vs. NA: P = 0.09; PRT vs. NA: P = 0.26). Only PRT caused significant improvements in PF (mean +/- SE: 10.4 +/- 3.8 points on a 100-point scale) and 7 measures of strength (P values: 0.04 to <0.001). There were no overall differences between groups in PF change. Among patients with impaired baseline PF, however, OX was significantly less effective than NA and PRT was significantly better than NA. All treatments led to increases in protein intake and performance; NA and PRT also increased caloric intake. The institutional costs per subject in this trial were 983 dollars for NA, 3772 dollars for OX, and 3189 dollars for PRT. At a community-based level of intensity, the institutional costs per QALY were 45,000 dollars (range: 42,000 dollars-64,000 dollars) for NA, 147,000 dollars (range: 147,000 dollars-163,000 dollars) for OX, and 31,000 dollars (range: 21,000 dollars-44,000 dollars) for PRT. CONCLUSIONS: OX and PRT induce similar improvements in body composition, but PRT improves quality of life more than nutrition or OX, particularly among patients with impaired PF. PRT was the most cost-effective intervention, and OX was the least cost-effective intervention.

Adult↗
PubMed2005

The effect of drug abuse on body mass index in Hispanics with and without HIV infection.

OBJECTIVE: There is a widely held view that the lower weight of drug abusers is attributable to diet. However, many studies on the dietary intake of drug abusers have failed to find energy insufficiency, while non-dietary factors have rarely been examined. The purpose of this study was to examine non-dietary factors that could affect the weight of drug abusers with and without HIV infection. DESIGN: Participants were recruited into one of three groups: HIV-positive drug abusers (n=85), HIV-negative drug abusers (n=102) and HIV-positive persons who do not use drugs ('non-drug abusers', n=98). Non-dietary factors influencing weight included infection with HIV and/or hepatitis, malabsorption, resting energy expenditure and physical activity. SETTING: The baseline data from a prospective cohort study of the role of drug abuse in HIV/AIDS weight loss conducted in Boston, USA. SUBJECTS: The first 286 participants to enroll in the study. RESULTS: HIV-positive drug abusers had a body mass index (BMI) that was significantly lower than that of HIV-positive non-drug abusers. The differences in weight were principally differences in fat. In the men, cocaine abuse, either alone or mixed with opiates, was associated with lower BMI, while strict opiate abuse was not. Infection with HIV or hepatitis, intestinal malabsorption, resting energy expenditure and physical activity, as measured in this study, did not explain the observed differences in weight and BMI. CONCLUSIONS: Drug abuse, and especially cocaine abuse, was associated with lower weight in men. However, infection with HIV and/or hepatitis, malabsorption and resting energy expenditure do not explain these findings.

Adult↗
PubMed2005

Predictors of bone mineral density in human immunodeficiency virus-1 infected children.

OBJECTIVES: To compare bone mineral density (BMD) among human immunodeficiency virus (HIV)-infected children with population norms and to determine predictors of BMD in HIV-infected children. METHODS: Total body BMD was measured by dual energy x-ray absorptiometry in 37 HIV-infected children and nine sibling controls at baseline. Clinical, dietary and anthropometric data were obtained at the time of the dual energy x-ray absorptiometry examination. Age- and gender-adjusted z scores were calculated for BMD, body mass index, weight and height from population standards. Age-adjusted percentiles were determined for dietary intake of calcium and vitamin D. Differences in BMD z scores between HIV-infected children and sibling controls were determined and adjusted for height and weight, as were independent risk factors for lower BMD among infected children. Eighteen HIV-infected children and 5 controls had serial BMD measures. RESULTS: Compared with population norms, HIV-infected children had significantly lower BMD z scores (-0.51 SD, P = 0.004), in contrast with controls who had normal z scores (0.38 SD, P = 1.0). However, there was no difference in BMD z scores between HIV-infected children and the small number of sibling controls, adjusted for height and weight. Among HIV-infected children, lower BMD z scores were independently associated with lower weight z scores (P < 0.0001), lower height z scores (P = 0.01), advanced (stage B or C) HIV stage (P = 0.01) and age greater than 8 years (P < 0.0001). In the same model, multivitamin use (P = 0.009) and African American race (P = 0.001) were associated with better BMD z scores, with nevirapine use showing borderline positive effect (P = 0.06). All results were adjusted for Tanner stage. Change in BMD z score over time showed that there was no change or an increase in BMD in 100% of controls but in only 44% of the HIV-infected children (P = 0.09). CONCLUSION: When compared with population norms, HIV-infected children had lower than expected bone mass for their age and gender that may be attributable to delays in growth, sexual maturity, time (length of HIV infection), ethnicity and disease severity. Dietary intake of calcium and vitamin D were not associated with bone loss, but most children had suboptimal intake. However, multivitamin use was strongly associated with better bone mineral density.

Absorptiometry, Photon↗
PubMed2005

Predicting CD4 count using total lymphocyte count: a sustainable tool for clinical decisions during HAART use.

Understanding the total lymphocyte count (TLC)-CD4 count relationship could aide design predictive instruments for making clinical decisions during antiretroviral therapy, especially in underserved resource-poor settings. We performed multiple regression analyses to assess the prediction of CD4 count using TLC on 771 participants with 4,836 visits. In linear and logistic regression TLC, hemoglobin, gender, history of AIDS, and weight predicted CD4 count and CD4 < 200, respectively, before and after highly active antiretroviral therapy (HAART) use. On HAART, the adjusted odds ratios (OR) for TLC < 1500 (optimal TLC cutoff) were 5.1 (95%CI 4.0, 6.5; P < 0.001), and off HAART, 4.6 (95%CI 3.4, 6.2: P < 0.001) with high predictive power. TLC predicts CD4 count and CD4 < 200 cells/microL well during HAART. Including the additional factors improves performance. TLC is simple and inexpensive and can be used in many ways to develop clinical decision-making tools in underserved resource-poor settings during HAART therapy.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Understanding the role of HIV load in determining weight change in the era of highly active antiretroviral therapy.

BACKGROUND: In this prospective cohort study, we determined the relationship between human immunodeficiency virus (HIV) RNA load and body weight in patients with HIV infection. METHODS: Repeated-measures analysis was restricted to patients with >or=2 study visits, 4-9-month intervals between study visits, and complete data on virus load, resting energy expenditure (REE), and highly active antiretroviral therapy (HAART). The outcome was change in body weight across study intervals. The main predictor was virus load. Separate analyses were performed for weight change in patients receiving and patients not receiving HAART. RESULTS: The eligible sample consisted of 318 participants associated with 1886 study intervals. Sixty-one patients (19%) were women, and 173 (54%) were undergoing HAART at the time of enrollment. There was a significant interaction (P=.01) between virus load and HAART use. In the absence of HAART, each log(10) increase in virus load was associated with a 0.92-kg decrease in body weight (P=.003), but during HAART, virus load was not significantly associated with weight change. During HAART, a CD4(+) cell count decrease of 100 cells/mm(3), rather than a change in the virus load, was associated with a 0.35-kg decrease in body weight (P<.001). REE was independently associated with weight change in both models (P<.001). CONCLUSIONS: Patients with HIV infection who are losing weight and are not taking HAART should be considered for HAART. Patients who are already receiving HAART and have unsuppressed virus loads may benefit virologically from an intensified regimen, because such a regimen may lead to complete suppression if there is an accompanying increase in CD4(+) cell counts. Further research is needed to understand the strong independent effect of changes in REE among patients receiving and patients not receiving HAART.

Adult↗
PubMed2004

Body-composition changes in the simian immunodeficiency virus-infected juvenile rhesus macaque.

BACKGROUND: Body-composition changes are common in individuals infected with human immunodeficiency virus. The purpose of the present study was to measure, as a model of wasting in acquired immunodeficiency syndrome (AIDS), longitudinal body-composition changes in macaques infected with simian immunodeficiency virus (SIV). METHODS: Twelve juvenile macaques were inoculated with SIVmac239. Immunologic, virologic, somatometric, and dual-energy x-ray-absorptiometry measurements were performed prospectively every 4 weeks for 72 weeks and were compared to measurements taken from 8 uninfected control macaques. RESULTS: During the first 4 weeks, body-fat percentage decreased in the SIV-infected macaques while lean-tissue percentage increased; during weeks 4-72, these macaques lost a greater percentage of total fat tissue but had more subcutaneous-fat deposition than did the uninfected control macaques. Just prior to death, the SIV-infected macaques that died (n=7) had a greater loss in body-mass index, abdominal fat, fat tissue, and lean tissue, compared with that in SIV-infected macaques that survived (n=5). CONCLUSIONS: Body-composition changes in SIV-infected juvenile macaques exhibit 3 phases: during acute infection, loss of body weight from fat tissue; a compensation period during which macaques grow, but at a reduced rate; and a terminal phase, during which tissue is lost from all body compartments. The SIV-infected juvenile macaque provides a useful model for the investigation of wasting in AIDS, particularly for pediatric AIDS wasting.

Abdomen↗
PubMed2004

Dietary intake and body mass index in HIV-positive and HIV-negative drug abusers of Hispanic ethnicity.

OBJECTIVE: Malnutrition in drug abusers has been attributed to poor diet. However, previous studies are conflicting. Many studies have not considered possible concurrent HIV disease. The purpose of this study was to determine the relationship between drug abuse and dietary intake in Hispanic Americans with and without HIV infection. DESIGN: Dietary intake was measured using 3-day food records and 24-hour dietary recalls in three groups: HIV-positive drug abusers, HIV-negative drug abusers and HIV-positive persons who do not use drugs ('non-drug abusers'). SETTING: The baseline data from a prospective cohort study of the role of drug abuse in HIV/AIDS weight loss and malnutrition conducted in Boston, Massachusetts, USA. SUBJECTS: The first 284 participants to enroll in the study. RESULTS: HIV-positive drug abusers had a body mass index (BMI) that was significantly lower than that of HIV-positive non-drug abusers. Reported energy, fat and fibre intakes did not differ between groups. All groups had median reported intakes of vitamin A, vitamin B6, vitamin B12, selenium and zinc that were in excess of the dietary reference values (DRI). Intakes of alpha-tocopherol were below the DRI, but did not differ from intakes of the general US population. However, increasing levels of drug abuse were associated with lower reported intakes of vitamin B6, vitamin B12, selenium and zinc. CONCLUSIONS: Overall, this study does not support the notion that dietary intake can explain the lower BMI of HIV-positive drug abusers. Further studies examining non-dietary determinants of nutritional status in drug abusers are warranted.

Adult↗