Tamsin A Knox

University of Illinois at Chicago, Chicago, Illinois, United States

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Publications (38)213.64 Total impact

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    ABSTRACT: Abstract We examined the association between metabolic syndrome (MS) and its individual defining criteria on all-cause mortality in human immunodeficiency virus (HIV)-infected persons. We used data from 567 HIV-infected participants of the Nutrition for Healthy Living study with study visits between 9/1/2000 and 1/31/2004 and determined mortality through 12/31/2006. MS was defined using modified National Cholesterol Education Program guidelines. Cox proportional hazards for all-cause mortality were estimated for baseline MS status and for its individual defining criteria. There were 83 deaths with median follow-up of 63 months. Baseline characteristics associated with increased risk of mortality were: older age in years (univariate hazard ratio [HR] 1.04, p<0.01), current smoking (HR 1.99, p=0.02), current heroin use (HR 1.97, p=0.02), living in poverty (HR 2.0, p<0.01), higher mean HIV viral load (HR 1.81, p<0.01), and having a BMI <18 (HR 5.84, p<0.01). For MS and its criteria, only low HDL was associated with increased risk of mortality on univariate analysis (HR 1.84, p=0.01). However, metabolic syndrome (adjusted HR 2.31, p=0.02) and high triglycerides (adjusted HR 3.97, p<0.01) were significantly associated with mortality beyond 36 months follow-up. MS, low HDL, and high triglycerides are associated with an increased risk of mortality in HIV-infected individuals.
    AIDS patient care and STDs 05/2013; 27(5):266-71. · 2.68 Impact Factor
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    ABSTRACT: This study assessed the association of HIV RNA with indirect markers of liver injury including FIB-4 index, liver enzymes and platelet counts in a high-risk Hispanic population. The data were derived from a prospective study that included 138 HIV/hepatitis C (HCV)-coinfected and 68 HIV-infected participants without hepatitis C or B co-infection (mono-infected). In unadjusted analyses, detectable HIV viral load (vs undetectable, <400 copies/mL) was associated with a 40% greater odds (OR 1.4, 95% CI: 1.1-1.9, P = 0.016) of FIB-4 > 1.45 in the HIV/HCV-coinfected group and 70% greater odds of FIB-4 > 1.45 (OR 1.7, 95% CI: 1.0-2.8; P = 0.046) in the HIV-mono-infected group. In multivariable analyses, a 1 log(10) increase in HIV RNA was associated with a median increase in FIB-4 of 12% in the HIV/HCV-coinfected group and 11% in the HIV-mono-infected group (P < 0.0001). Among the HIV/HCV-coinfected group, the elevating effect of HIV RNA on FIB-4 was strongest at low CD4 counts (P = 0.0037). Among the HIV-mono-infected group, the association between HIV RNA and FIB-4 was independent of CD4 cell counts. HIV RNA was associated with alterations in both liver enzymes and platelet counts. HIV antiretroviral therapy was not associated with any measure of liver injury examined. This study suggests that HIV may have direct, injurious effects on the liver and that HIV viral load should be considered when these indirect markers are used to assess liver function.
    Journal of Viral Hepatitis 02/2012; 19(2):e202-11. · 3.08 Impact Factor
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    ABSTRACT: Elevated serum triglyceride and low HDL-cholesterol concentrations have been reported in persons with HIV. The effect of a dietary intervention plus n-3 (omega-3) fatty acid supplementation on serum triglycerides and markers of insulin sensitivity was investigated. Fifty-four persons with HIV and elevated serum triglycerides (>150 mg/dL) and/or abnormal Quantitative Insulin Sensitivity Check Index values (<0.35 but >0.30) were recruited for a dietary intervention in which total fat, type of fat, fiber, and glycemic load were controlled along with supplementation with n-3 fatty acids to achieve an intake of 6 g/d. The subjects were randomly assigned to an intervention or control group, and serum lipids, markers of insulin sensitivity, and serum phospholipid fatty acids were measured in both groups at baseline, 3 wk, and 13 wk. Triglycerides in the intervention group decreased from a median of 180 mg/dL (interquartile range: 141, 396) to 114 mg/dL (interquartile range: 84, 169) from baseline to 3 wk, whereas they remained stable in the control group (P = 0.003). Serum phospholipid fatty acids indicated a decrease in de novo lipogenesis and a decrease in arachidonic acid (% nmol; P <or= 0.001) in the intervention group. At 3 wk, the insulin area under the curve decreased but not significantly. Diet and n-3 fatty acid supplementation dramatically reduced serum triglycerides, decreased arachidonic acid in the phospholipids fraction, and appeared to decrease the de novo lipogenesis associated with the metabolic syndrome in the intervention group.
    American Journal of Clinical Nutrition 10/2009; 90(6):1566-78. · 6.50 Impact Factor
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    ABSTRACT: The effects of hepatitis and drug use on nutritional problems in HIV infection have rarely been examined despite the importance of drug use in the global HIV pandemic. We examined the effects of HIV, hepatitis C, and drug use on serum micronutrients in 300 US Hispanic adults. Chronic hepatitis C infection was associated with lower serum retinol (-8.2 microg/dl, P < 0.0001), alpha-tocopherol (-0.10 ln microg/dl, P = 0.024), and carotenoids (-19.8 microg/dl, P < 0.0001). HIV infection was associated with lower selenium (-6.1 microg/l, P = 0.028). Elevated triglycerides in HIV infection were associated with higher serum retinol and alpha-tocopherol. Drug use was not independently associated with micronutrient alterations. We conclude that hepatitis C is an important determinant of low serum micronutrients, and should be considered in any nutritional assessment of HIV infected populations. As the safety of micronutrient supplementation is not established, policy for appropriate HIV clinical care should distinguish between populations with and without hepatitis coinfection.
    Journal of Public Health Policy 09/2009; 30(3):285-99. · 1.48 Impact Factor
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    ABSTRACT: Ritonavir is a powerful inhibitor of cytochrome P450 3A (CYP3A) that metabolizes many antiretrovirals. We examined the effect of ritonavir and of chronic viral hepatitis (CVH) status on CYP3A activity. Twenty-six HIV-positive men (13 with CVH, 16 on chronic ritonavir-based highly active antiretroviral therapy) received oral and intravenous midazolam, a probe for CYP3A phenotypic activity. CYP3A activity was expressed as oral clearance of the midazolam probe. In HIV-positive subjects not on ritonavir, CYP3A activity (mean +/- SD) did not differ between subjects by CVH (no CVH, controls: 28.5 +/- 9.0 vs. CVH+: 23.2 +/- 6.2 mL/min/kg, not significant). In those on ritonavir (R), CYP3A activity was 7% of controls (R: 2.1 +/- 0.8 vs. no R 28.5 +/- 9.0 mL/min/kg, P < 0.0004). CYP3A activity in subjects on ritonavir and with CVH was further reduced to 4% of controls (no CVH, R+ 2.1 +/- 0.8 vs. R+, CVH+ 1.0 +/- 0.4 mL/min/kg, P < 0.006). Ritonavir markedly decreases CYP3A activity. In the presence of CVH, ritonavir-based therapy further reduces CYP3A activity by half. Coinfection with CVH impairs CYP3A activity in the presence of the CYP3A inhibitor ritonavir.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 12/2008; 49(4):358-68. · 4.65 Impact Factor
  • Rita Isaac, Reginald G Alex, Tamsin A Knox
    Tropical Doctor 07/2008; 38(3):133-4. · 0.61 Impact Factor
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    ABSTRACT: Human immunodeficiency virus (HIV)-infected persons have an increased risk of chronic kidney disease (CKD). Serum creatinine level may underestimate the prevalence of CKD in subjects with decreased lean body mass or liver disease. Level of serum cystatin C, an alternative kidney function marker, is independent of lean body mass. Cross-sectional. 250 HIV-infected subjects on highly active antiretroviral therapy in the Nutrition for Healthy Living (NFHL) cohort; 2,628 National Health and Nutrition Examination Survey (NHANES) 2001-2002 subjects. Comparison of serum creatinine levels in NFHL to those in NHANES subjects; comparison of CKD in NFHL subjects ascertained using serum creatinine versus cystatin C levels. Standardized serum creatinine, serum cystatin C, glomerular filtration rate (GFR) estimated from serum creatinine and cystatin C levels. Creatinine levels were lower in NFHL than NHANES subjects despite greater rates of hepatitis, diabetes, and drug use (mean difference, -0.18 mg/dL; P < 0.001 adjusted for age, sex, and race). Of NFHL subjects, only 2.4% had a creatinine-based estimated GFR less than 60 mL/min/1.73 m(2), but 15.2% had a cystatin-based estimated GFR less than 60 mL/min/1.73 m(2). GFR was estimated rather than measured. Other factors in addition to GFR may affect creatinine and cystatin C levels. Measurements of proteinuria were not available. Serum creatinine levels may overestimate GFRs in HIV-infected subjects. Kidney disease prevalence may be greater than previously appreciated.
    American Journal of Kidney Diseases 06/2008; 51(6):914-24. · 5.29 Impact Factor
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    ABSTRACT: The effect of depression on dietary intake has not, to our knowledge, been examined in persons with HIV infection. We conducted a longitudinal analysis of participants in the Nutrition for Healthy Living Study (NFHL). We measured changes in dietary macronutrient intake in participants who developed depression and, using multiple regression analysis, compared the changes with a control group of patients who did not become depressed. Ninety patients developed depression during the observation period, and we compared these with 152 non-depressed controls. The two groups had similar age and body mass index (BMI) at baseline, but those who developed depression were more likely to be female, less educated and had lower incomes. After adjustment, compared with non-depressed participants, those who developed depression had significantly greater decreases in the following daily intakes: total energy (-341 kcal, P = 0.006), protein (-12.3 g, P = 0.02), total fat (-18.5 g, P = 0.008), carbohydrate (-36.8 g, P = 0.02), total fibre (-4.3 g, P = 0.001) and saturated fat (-6.7 g, P = 0.01). There were no significant differences in the daily intakes of simple sugars and long-chain n-3 fatty acids, or BMI. Depression is associated with decreases in total daily energy intake and in six of the eight dietary components we measured. Clinicians should be aware that depression-associated nutritional deficiencies may complicate the care of persons with HIV.
    Public Health Nutrition 03/2008; 11(2):124-31. · 2.25 Impact Factor
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    ABSTRACT: Studies of the progression liver fibrosis in human immunodeficiency virus (HIV) and hepatitis C virus-coinfected patients suggest that cirrhosis is associated with immunosuppression, as measured by low absolute CD4(+) T cell counts. However, we hypothesized that, in patients with advanced liver disease, low CD4(+) T cell counts may occur secondary to portal hypertension and splenic sequestration, regardless of the presence or absence of HIV infection. Sixty HIV-seronegative outpatients with cirrhosis were enrolled during the period 2001-2003 in a prospective, cross-sectional study of the association between liver disease and CD4(+) T cell counts and percentages. Demographic characteristics, liver disease-related characteristics, and laboratory results--including CD4(+) T cell parameters--were collected. A total of 39 patients (65%) had a low CD4(+) T cell count; 26 patients (43%) and 4 patients (7%) had CD4(+) T cell counts <350 and <200 cells/mm(3), respectively. Abnormal CD4(+) T cell counts were associated with splenomegaly (P=.03), thrombocytopenia (P=.002), and leukopenia (P<.001). The percentage of CD4(+) T cells was normal in 95% of patients who had a low absolute CD4(+) T cell count. CD4(+) T cell counts were significantly lower among cirrhotic patients than among 7638 HIV-seronegative historic control subjects without liver disease. Cirrhosis is associated with low CD4(+) T cell counts in the absence of HIV infection. Discordance between low absolute CD4(+) T cell counts and normal CD4(+) T cell percentages may be attributable to portal hypertension and splenic sequestration. Our findings have significant implications for the use and interpretation of absolute CD4(+) T cell counts in HIV-infected patients with advanced liver disease.
    Clinical Infectious Diseases 03/2007; 44(3):431-7. · 9.37 Impact Factor
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    ABSTRACT: Low serum micronutrient levels were common before widespread use of highly active antiretroviral therapy (HAART) and were associated with adverse outcomes. Few data are available on micronutrient levels in subjects taking HAART. To determine the prevalence of low serum retinol, alpha-tocopherol, zinc, and selenium in HIV-infected subjects taking HAART and to assess the association of micronutrient levels with HIV disease status. Cross-sectional. Nutrition for Healthy Living (NFHL) study. HIV-infected subjects on HAART. Retinol, alpha-tocopherol, zinc, and selenium were determined in frozen serum samples from 171 men and 117 women. Low serum levels were defined as retinol <30 microg/dL, selenium <85 microg/L, alpha-tocopherol <500 microg/dL, and zinc <670 microg/L. Association of micronutrient quartiles with CD4 cell count, CD4 count <200 cells/mm, HIV viral load (VL), and undetectable VL was assessed using adjusted multivariate regression. Five percent of men and 14% of women had low retinol, 8% of men and 3% of women had low selenium, and 7% of men and no women had low alpha-tocopherol. Forty percent of men and 36% of women had low zinc, however. Subjects in the upper quartiles of zinc had lower log VL levels than those in the lowest quartile (significant for women). Subjects in the upper quartiles of selenium also tended to have lower VL levels compared with those in the lowest quartile. Surprisingly, women in the upper quartiles of retinol had higher log VLs than those in the lowest quartile. There was no significant association of any micronutrient with CD4 cell count or likelihood of CD4 count <200 cells/mm. The level of CD4 cell count influenced the association of retinol with log VL in men, however. In men with CD4 counts >350 cells/mm, those with higher retinol had higher log VLs compared with the lowest quartile, whereas in men with CD4 counts <350, those with higher retinol levels had lower log VLs compared with the lowest quartile. Low retinol, alpha-tocopherol, and selenium are uncommon in HIV-infected subjects on HAART. Zinc deficiency remains common, however. Decreased retinol levels in women and in men with CD4 counts >350 cells/mm and increased zinc and selenium levels in both genders may be associated with improved virologic control.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 12/2006; 43(4):475-82. · 4.65 Impact Factor
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    ABSTRACT: 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). 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. 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. 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.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 10/2005; 40(2):202-11. · 4.65 Impact Factor
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    ABSTRACT: Although the incidence of most AIDS-defining opportunistic infections, including HIV wasting syndrome, has dramatically decreased since the introduction of highly active antiretroviral therapy (HAART), previous studies have shown that weight loss and wasting are still common in HIV-infected persons. We examined the 6-month risk and determinants of > or =5% weight loss during the period when the use of combination antiretroviral therapy and HAART was commonplace among 713 participants enrolled in the Nutrition for Healthy Living cohort in Boston, Massachusetts between 1995 and 2003. There was a significant 50% increase in the 6-month risk of > or =5% weight loss in the later HAART years (1998-2003) compared with the early HAART years (1995-1997) among most of the participants who reported they were not trying to lose weight (P = 0.002). In addition to calendar time, several other variables were significantly independently associated with risk of > or =5% weight loss, including use of injection drugs; living below the federal poverty level; higher body mass index (BMI; > or =25 kg/m(2)); lower CD4 cell count; higher HIV viral load; and presence of diarrhea, nausea, or fever. The characteristics of weight loss in the later HAART years did not differ from the early HAART years with respect to initial body composition (eg, weight, BMI, triceps skinfold thickness) or changes in body composition during the periods of weight loss. In summary, we have found that the risk of > or =5% unintentional weight loss over 6-month intervals is on the rise in our cohort of HIV-infected participants, despite better control of HIV infection in recent years. Although we still do not know the exact cause of this increase, the fact that it exists indicates the need for clinicians who take care of HIV-infected patients to continue to pay attention to weight loss among particular segments of their patient population. This is particularly important because recent studies have shown that even a 5% weight loss in 6 months markedly increases the risk of death.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 09/2005; 40(1):70-6. · 4.65 Impact Factor
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    ABSTRACT: In this prospective cohort study, we determined the relationship between human immunodeficiency virus (HIV) RNA load and body weight in patients with HIV infection. 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. 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). 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.
    Clinical Infectious Diseases 02/2005; 40(1):167-73. · 9.37 Impact Factor
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    ABSTRACT: This review examines the relationship among malabsorption, diarrhea, dietary intake, and body composition in an outpatient cohort of individuals with HIV infection. Twenty-three percent of the participants had malabsorption, which was not associated with the presence of current or chronic diarrhea. In this "outpatient" HIV cohort with a mean body-mass index (BMI) of 25 kg/m2, the presence of malabsorption did not have adverse nutritional outcomes in terms of body weight, lean body mass, hemoglobin, or albumin. The diets of those with or without malabsorption did not meet the goals of the Dietary Guidelines for Americans. Median dietary intake was high in percentage of total fat and saturated fat and low in total fiber intake and some key micronutrients.
    Nutrition in Clinical Care 01/2005; 8(1):37-43.
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    ABSTRACT: In human immunodeficiency virus (HIV) disease, symptoms of underlying illness may promote weight loss through decreased caloric intake, increased metabolic needs, or nutrient malabsorption. We evaluated disease symptoms as predictors of acute weight loss (i.e., loss of > or =5% of weight). HIV-infected men and women (n=415) were telephoned every 5 weeks to obtain information about weight and recent symptoms. Weight change between each pair of consecutive calls (telephone intervals, 2814) was calculated. Acute weight loss occurred across 4.5% of intervals and among 24% of individuals. Patients reported > or =1 symptom before 58% of telephone intervals. The most common symptoms or symptom complexes before intervals were diarrhea (21% of patients), anorexia (17%), upper respiratory symptoms (16%), skin symptoms (12%), and abdominal pain (12%). Trouble swallowing (6%) and oral symptoms (7%) were less common. Risk of acute weight loss was significantly increased when oral symptoms or trouble swallowing were present, and it was decreased when highly active antiretroviral therapy (HAART) was used or when diarrhea was not present. Even when HAART is being administered, clinicians should remain vigilant regarding weight loss, oral symptoms, and trouble swallowing.
    Clinical Infectious Diseases 12/2003; 37(10):1349-56. · 9.37 Impact Factor
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    ABSTRACT: Nutritional status should be assessed at regular intervals as part of management of human immunodeficiency virus (HIV) infection. The simplest approach to assessment is serial weight measurement. A comprehensive nutritional assessment includes (1) anthropometric measurements of body composition; (2) biochemical measurements of serum protein, micronutrients, and metabolic parameters; (3) clinical assessment of altered nutritional requirements and social or psychological issues that may preclude adequate intake; and (4) measurement of dietary intake. Techniques for measuring body composition of fat and lean body mass include anthropometry and bioelectric impedance analysis. Other techniques, including dual X-ray absorptiometry (DXA), hydrodensitometry, total body potassium measurement, and cross-sectional computed tomography or magnetic resonance imaging are available in research centers. Anthropometry, including waist-hip ratios, regional DXA, and cross-sectional imaging, is best for detecting morphologic changes associated with fat redistribution syndrome. Nutritional assessment and intervention in children with HIV can help to prevent stunted growth and development.
    Clinical Infectious Diseases 05/2003; 36(Suppl 2):S63-8. · 9.37 Impact Factor
  • Hepatology 01/2003; 38:429-429. · 12.00 Impact Factor
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    ABSTRACT: To evaluate the contribution of acquired immune deficiency syndrome-defining conditions (ADCs) in human immunodeficiency virus (HIV)-associated wasting, we analyzed longitudinal data from 671 participants in a nutrition and HIV cohort study. Data on ADCs, height, and weight were collected at baseline and during 6 monthly study visits. The frequency of ADCs decreased over time, but the relative risk (RR) of wasting (decrease in body mass index [BMI] to <20 kg/m(2)) increased with a history of >1 ADC; the RR of wasting increased 1.3-fold with each additional historical ADC. Any ADC during the 6 months prior to a study visit was associated with a decrease in BMI to <20 kg/m(2). The risk of wasting increased 2.7-fold with each additional recent ADC. These risks were not altered when adjusted for socioeconomic status, CD4 cell count, energy intake, or baseline BMI. Although ADCs contribute to the development of wasting, their contribution is relatively small.
    Clinical Infectious Diseases 01/2003; 37 Suppl 2:S81-4. · 9.37 Impact Factor
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    ABSTRACT: The dietary intake of micronutrients and serum micronutrient status have been topics of concern in relation to human immunodeficiency virus (HIV) progression. Most data, however, were collected prior to the introduction of protease inhibitors (PIs). We analyzed dietary intake and serum values of vitamin B(12), including the effect of PIs, in a cohort of persons with HIV infection. During intervals with no PI use, each 1 microg/day increase in B(12) intake was associated with a 1.06 pg/mL increase in serum B(12) levels. However, during intervals with PI use, each 1 microg/day increase in intake was associated with only a 0.12 increase in serum B(12) levels. Adequate serum B(12) levels (>350 pg/mL) cannot be assumed even in the presence of PIs, and dietary supplementation may not be adequate to significantly increase serum B(12) levels. Serum B(12) levels should be determined yearly in persons with HIV infection, regardless of whether they are receiving PI treatment.
    Clinical Infectious Diseases 01/2003; 37 Suppl 2:S124-31. · 9.37 Impact Factor
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    ABSTRACT: The nature of body-composition changes in HIV-associated weight loss is unclear. We examined the relation between the initial percentage of body fat and the composition of weight loss in men and women with HIV infection. HIV-positive adults were seen at semiannual clinic visits, at which time weight, fat, and fat-free mass were determined. The unit of analysis was the person-interval. Five hundred fifty-one persons contributed 2266 intervals of data, of which 311 (14%) were intervals in which weight loss was >/= 5% of initial (start of interval) weight. Of these, 208 (67%) intervals met the criteria for analysis (123 from men and 85 from women). Loss of fat-free mass was dependent on the initial percentage of body fat in the men with < 32% body fat. A plot of the initial percentage of body fat compared with loss of fat-free mass (kg) suggested a nonlinear relation over the range of body fat examined. There was no clear relation between the initial percentage of body fat and loss of fat-free mass in the women. In men with HIV-associated weight loss, the weight lost as fat-free mass depends on the initial percentage of body fat at low levels of body fat but appears to be independent of initial percentage of body fat at high levels of body fat. In women with HIV-associated weight loss who have normal-to-high body fat stores, loss of fat-free mass is independent of the initial percentage of body fat.
    American Journal of Clinical Nutrition 01/2003; 76(6):1428-34. · 6.50 Impact Factor

Publication Stats

900 Citations
213.64 Total Impact Points


  • 2013
    • University of Illinois at Chicago
      Chicago, Illinois, United States
  • 2000–2007
    • Tufts Medical Center
      • • Division of Geographic Medicine and Infectious Diseases
      • • Division of Gastroenterology and Hepatology
      Boston, MA, United States
  • 2000–2002
    • Tufts University
      • • Clinical Research Division
      • • Department of Public Health and Community Medicine
      Boston, GA, United States
  • 2000–2001
    • New England Baptist Hospital
      Boston, Massachusetts, United States