Grace A. McComsey

Bone Mineral Density and Fractures in Antiretroviral-Naive Persons Randomized to Receive Abacavir-Lamivudine or Tenofovir Disoproxil Fumarate-Emtricitabine Along With Efavirenz or Atazanavir-Ritonavir: AIDS Clinical Trials Group A5224s, a Substudy of ACTG A5202

BACKGROUND Long-term effects of abacavir (ABC)-lamivudine (3TC), compared with tenofovir (TDF)-emtricitabine (FTC) with efavirenz (EFV) or atazanavir plus ritonavir (ATV/r), on bone mineral density (BMD) have not been analyzed. METHODS A5224s was a substudy of A5202, in which HIV-infected treatment-naive participants were randomized and blinded to receive ABC-3TC or TDF-FTC with open-label EFV or ATV/r. Primary bone end points included Dual-emission X-ray absorbtiometry (DXA)-measured percent changes in spine and hip BMD at week 96. Primary analyses were intent-to-treat. Statistical tests used the factorial design and included linear regression, 2-sample t, log-rank, and Fishers exact tests. RESULTS Two hundred sixty-nine persons randomized to 4 arms of ABC-3TC or TDF-FTC with EFV or ATV/r. At baseline, 85% were male, and 47% were white non-Hispanic; the median HIV-1 RNA load was 4.6 log(10) copies/mL, the median age was 38 years, the median weight was 76 kg, and the median CD4 cell count was 233 cells/μL. At week 96, the mean percentage changes from baseline in spine and hip BMD for ABC-3TC versus TDF-FTC were -1.3% and -3.3% (P = .004) and -2.6% and -4.0% (P = .024), respectively; and for EFV versus ATV/r were -1.7% and -3.1% (P = .035) and -3.1% and -3.4% (P = .61), respectively. Bone fracture was observed in 5.6% of participants. The probability of bone fractures and time to first fracture were not different across components. CONCLUSIONS Compared with ABC-3TC, TDF-FTC-treated participants had significantly greater decreases in spine and hip BMD, whereas ATV/r led to more significant losses in spine, but not hip, BMD than EFV. Clinical Trials Registration. NCT00118898.

Bone Disease in HIV Infection: A Practical Review and Recommendations for HIV Care Providers

Low bone mineral density (BMD) is prevalent in human immunodeficiency virus (HIV)-infected subjects. Initiation of antiretroviral therapy is associated with a 2%-6% decrease in BMD over the first 2 years, a decrease that is similar in magnitude to that sustained during the first 2 years of menopause. Recent studies have also described increased fracture rates in the HIV-infected population. The causes of low BMD in individuals with HIV infection appear to be multifactorial and likely represent a complex interaction between HIV infection, traditional osteoporosis risk factors, and antiretroviral-related factors. In this review, we make the point that HIV infection should be considered as a risk factor for bone disease. We recommend screening patients with fragility fractures, all HIV-infected post-menopausal women, and all HIV-infected men ⩾50 years of age. We also discuss the importance of considering secondary causes of osteoporosis. Finally, we discuss treatment of the more severe cases of bone disease, while outlining the caveats and gaps in our knowledge.

Loss of bone mineral density after antiretroviral therapy initiation, independent of antiretroviral regimen

Background:Decreased bone mineral density (BMD) has been described in HIV-infected patients initiating antiretroviral therapy (ART), but the contributions of ART and immunologic and/or virologic factors remain unclear. Methods:We compared total BMD changes over 96 weeks in 106 ART-naive HIV-infected subjects who were randomized to receive efavirenz (EFV) + zidovudine/lamivudine (n = 32) or lopinavir/ritonavir (LPV/r) + zidovudine/lamivudine induction (n = 74) for 24-48 weeks followed by LPV/r monotherapy. We also sought to identify factors associated with BMD loss, including markers of systemic inflammation [soluble tumor necrosis factor-α receptors (sTNFR I and II)]. Results:After 96 weeks, the mean percent change from baseline in total BMD was −2.5% (LPV/r) and −2.3% (EFV) (P < 0.01 for within-group changes in either arm; P = 0.86 for between-group differences). No alteration in the rate of BMD change was observed upon simplification to LPV/r monotherapy. Although soluble tumor necrosis factor-α receptor II concentrations at baseline and 24 weeks were at least marginally associated with subsequent changes in BMD (P = 0.06 and P = 0.028, respectively), these associations were no longer significant after adjustment for CD4+ T cell count. Subjects with lower baseline CD4+ T cell count, non-black race, and higher baseline glucose demonstrated a higher risk for >5% decrease in BMD. Conclusions:Similar decreases in BMD over 96 weeks occurred in ART-naive subjects receiving either EFV-based regimen or LPV/r-based regimen, which was not altered by simplification to LPV/r monotherapy and was unrelated to markers of tumor necrosis factor-α activity.

Immunologic Failure Despite Suppressive Antiretroviral Therapy Is Related to Activation and Turnover of Memory CD4 Cells

BACKGROUND Failure to normalize CD4(+) T-cell numbers despite effective antiretroviral therapy is an important problem in human immunodeficiency virus (HIV) infection. METHODS To evaluate potential determinants of immune failure in this setting, we performed a comprehensive immunophenotypic characterization of patients with immune failure despite HIV suppression, persons who experienced CD4(+) T-cell restoration with therapy, and healthy controls. RESULTS Profound depletion of all CD4(+) T-cell maturation subsets and depletion of naive CD8(+) T cells was found in immune failure, implying failure of T-cell production/expansion. In immune failure, both CD4(+) and CD8(+) cells were activated but only memory CD4(+) cells were cycling at increased frequency. This may be the consequence of inflammation induced by in vivo exposure to microbial products, as soluble levels of the endotoxin receptor CD14(+) and interleukin 6 were elevated in immune failure. In multivariate analyses, naive T-cell depletion, phenotypic activation (CD38(+) and HLA-DR expression), cycling of memory CD4(+) T cells, and levels of soluble CD14 (sCD14) distinguished immune failure from immune success, even when adjusted for CD4(+) T-cell nadir, age at treatment initiation, and other clinical indices. CONCLUSIONS Immune activation that appears related to exposure to microbial elements distinguishes immune failure from immune success in treated HIV infection.

Relationship between Inflammatory Markers, Endothelial Activation Markers, and Carotid Intima-Media Thickness in HIV-Infected Patients Receiving Antiretroviral Therapy

BACKGROUND Human immunodeficiency virus (HIV)-infected patients are at increased risk of cardiovascular disease, which may be related to chronic inflammation and endothelial dysfunction despite virological control with antiretroviral therapy. The relationship between carotid intima-media thickness (IMT), a surrogate marker for cardiovascular disease, proinflammatory cytokines, and endothelial activation markers has not been fully explored in HIV-infected patients who are receiving antiretroviral therapy. METHODS We conducted a prospective, cross-sectional, observational study of treated HIV-infected patients and healthy control subjects to evaluate the relationship between carotid IMT, proinflammatory cytokines, endothelial activation biomarkers, and metabolic parameters in treated HIV-infected patients, compared with healthy control subjects. RESULTS We enrolled 73 HIV-infected patients and 21 control subjects. Common carotid artery and internal carotid artery IMT measurements, as well as tumor necrosis factor-alpha, high-sensitivity C-reactive protein, interleukin-6, myeloperoxidase, and soluble vascular cell adhesion molecule-1 levels were higher in the HIV-infected group. High-sensitivity C-reactive protein was the only biomarker that was positively correlated with carotid IMT in both groups. In the HIV-infected group, soluble vascular cell adhesion molecule-1 was positively correlated with all inflammatory cytokine levels. In multiple regression analysis, soluble vascular cell adhesion molecule-1, myeloperoxidase, and tumor necrosis factor-alpha levels were all associated with internal carotid artery IMT in the HIV-infected group, whereas age was associated with both common carotid artery and internal carotid artery IMT. CONCLUSIONS Enhanced endothelial activation, inflammation, and increased carotid IMT occur in HIV-infected patients despite antiretroviral therapy. Inflammatory markers are associated with endothelial activation, and both are associated with internal carotid artery IMT, supporting a potential role of inflammation in endothelial activation and cardiovascular disease in HIV infection.

Improvements in lipoatrophy, mitochondrial Dna levels and fat apoptosis after replacing stavudine with abacavir or zidovudine

Objective:To determine if stavudine (α4T)-associated mitochondrial toxicity could be reversed by substitution with another nucleoside reverse transcriptase inhibitor. As apoptosis and dysfunction of electron transport chain (ETC) activities may underlie mitochondrial toxicity, these parameters were also evaluated. Design:The 16 participants (on d4T for >3 years; with lipoatrophy and/or hyperlactatemia) substituted abacavir or zidovudine for stavudine in their antiretroviral regimen. Key parameters including dual-energy X-ray absorptiometry (DEXA) scans, fat apoptosis, mitochondrial DNA (mtDNA) content in peripheral blood mononuclear cells (PBMC), skeletal muscle and fat, as well as skeletal muscle mitochondrial ETC activities were evaluated at study entry and at 48 weeks after the substitution. Methods:Quantitative PCR was used to evaluate mtDNA levels and the presence of deletions/rearrangements; CLIA-validated methods for ETC activities; terminal deoxynucleotidyl transferase dUTP-digoxigenin nick-end labeling assays to evaluate adipocyte apoptosis; and DEXA scans to measure changes in body fat. Results:MtDNA was depleted at study entry in muscle, adipose tissue and PBMC but levels rebounded with respective mean increases of 141%, 146%, and 369% at week 48. Corresponding fat improvements were noted with DEXA increases of 21%, 11%, and 16% in arm, leg, and trunk, respectively. Quantitative adipocyte apoptosis were significantly increased at baseline (P < 0.01 versus HIV-negative controls), with a significant reduction at week 48 (P < 0.05 versus baseline). Mean values for seven mitochondrial enzyme activities assays at entry indicated substantial loss of function (48% to 85% of controls) with significant improvement of complex I activity by week 48. Conclusions:Substitution of stavudine with abacavir or zidovudine improves mitochondrial indices and fat apoptosis in the setting of lipoatrophy.

Association between initiation of antiretroviral therapy with efavirenz and decreases in 25-hydroxyvitamin D.

BACKGROUND We aimed to determine whether antiretroviral therapy (ART) initiation with efavirenz (EFV) is associated with decreases in 25-hydroxyvitamin D (25[OH]D) compared with non-EFV regimens. METHODS 25(OH)D was measured from stored plasma samples in 87 ART-naive HIV-positive patients prior to ART initiation with EFV-containing (n=51) or non-EFV-containing (89% with protease inhibitors; n=36) regimens from a single clinic in Cleveland (OH, USA). A repeat measurement was made 6-12 months after ART initiation. The change in 25(OH)D after ART initiation and the prevalence of patients with hypovitaminosis D (< or = 37.5 nmol/l [15 ng/ml]) after ART initiation was compared in those who initiated ART with and without EFV using multivariable linear and modified Poisson regression, respectively. RESULTS Prior to ART initiation, the median (interquartile range [IQR]) 25(OH)D concentration was 52.7 nmol/l (IQR 32.2-72.1), with 33% prevalence of hypovitaminosis D. After 6-12 months of ART, 25(OH)D decreased by a mean +/-se of -12.7 +/-3.7 nmol/l in the EFV group relative to the non-EFV group (P=0.001) after adjustment for baseline 25(OH)D concentration, race and season (non-summer versus summer) at the visit 6-12 months after ART initiation. Similarly, after multivariable adjustment, the risk of hypovitaminosis D after ART initiation was significantly higher in the EFV group compared with the non-EFV group (prevalence ratio 1.8 [95% confidence interval 1.2-2.8]; P=0.007). CONCLUSIONS ART initiation with EFV is associated with significant decreases in 25(OH)D and an increased risk of hypovitaminosis D compared with non-EFV regimens.

Alendronate with calcium and vitamin D supplementation is safe and effective for the treatment of decreased bone mineral density in HIV

Background:Decreased bone mineral density (BMD) is prevalent in HIV-infected patients. Bisphosphonates are currently the mainstay of treatment for postmenopausal and male osteoporosis in HIV-uninfected individuals; however, their efficacy and safety in HIV-infected patients remains unclear. Methods:In this prospective, randomized, placebo-controlled multicenter trial, we studied the effectiveness of calcium and vitamin D supplementation with or without alendronate in improving BMD in HIV-infected subjects receiving stable antiretroviral therapy. Subjects with secondary causes of osteoporosis were excluded. The study was powered to detect differences of 3.5% between arms and to detect a moderate sex effect in percentage change in lumbar spine BMD. All dual-energy X-ray absorptiometry scans were analysed centrally, blinded by arm. Results:The 82 subjects enrolled were 71% men, 77% white, with a baseline median age of 48 years, CD4 cell count of 469 cells/μl, and lumbar spine t-score of less than 2.1; 91% had HIV-RNA levels less than 400 copies/ml, and 99% were taking antiretroviral drugs. Compared with calcium/vitamin D alone, alendronate plus calcium/vitamin D resulted in significant improvements in BMD at the lumbar spine, total hip, and trochanter, but not at the femoral neck, compared with baseline. There were trends towards significant increases in BMD values in the calcium/vitamin D group at the lumbar spine, total hip, and femoral neck. There were no apparent sex differences in the responses to therapy. Alendronate was well tolerated, without significant adverse events. Conclusion:Once-weekly alendronate is safe and effective in the treatment of decreased BMD in HIV-infected patients.

Current Concepts in the Diagnosis and Management of Metabolic Complications of HIV Infection and Its Therapy

Changes in fat distribution, dyslipidemia, disordered glucose metabolism, and lactic acidosis have emerged as significant challenges to the treatment of human immunodeficiency virus (HIV) infection. Over the past decade, numerous investigations have been conducted to better define these conditions, identify risk factors associated with their development, and test potential therapeutic interventions. The lack of standardized diagnostic criteria, as well as disparate study populations and research methods, have led to conflicting data regarding the diagnosis and treatment of metabolic and body shape disorders associated with HIV infection. On the basis of a review of the medical literature published and/or data presented before April 2006, we have prepared a guide to assist the clinician in the detection and management of these complications.

Association Between Systemic Inflammation and Incident Diabetes in HIV-Infected Patients After Initiation of Antiretroviral Therapy

OBJECTIVE To determine whether systemic inflammation after initiation of HIV-antiretroviral therapy (ART) is associated with the development of diabetes. RESEARCH DESIGN AND METHODS We conducted a nested case-control study, comparing 55 previously ART-naive individuals who developed diabetes 48 weeks after ART initiation (case subjects) with 55 individuals who did not develop diabetes during a comparable follow-up (control subjects), matched on baseline BMI and race/ethnicity. Stored plasma samples at treatment initiation (week 0) and 1 year later (week 48) were assayed for levels of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and the soluble receptors of tumor necrosis factor-α (sTNFR1 and sTNFR2). RESULTS Case subjects were older than control subjects (median age 41 vs. 37 years, P = 0.001), but the groups were otherwise comparable. Median levels for all markers, except hs-CRP, decreased from week 0 to week 48. Subjects with higher levels of hs-CRP, sTNFR1, and sTNFR2 at 48 weeks had an increased odds of subsequent diabetes, after adjustment for baseline marker level, age, BMI at week 48, CD4 count at week 48 (< vs. >200 cells/mm3), and indinavir use (all Ptrend ≤ 0.05). After further adjustment for week 48 glucose, effects were attenuated and only sTNFR1 remained significant (odds ratio, highest quartile vs. lowest 23.2 [95% CI 1.28–423], P = 0.03). CONCLUSIONS Inflammatory markers 48 weeks after ART initiation were associated with increased risk of diabetes. These findings suggest that systemic inflammation may contribute to diabetes pathogenesis among HIV-infected patients.