Proteinuria and endothelial dysfunction in stable HIV-infected patients. A pilot study

Carotid intima-media thickness, flow-mediated dilatation and proteinuria in patients of human immunodeficiency virus-positive patients: A case-control study

Introduction

Endothelium-dysfunction (ED) is a surrogate marker of coronary atherosclerotic disease. Carotid intima-media thickness (CIMT), flow-mediated dilatation (FMD), and proteinuria are surrogate markers of ED. Few studies have shown that patients with HIV have impaired endothelial function and are thus at risk of accelerated atherosclerosis.

Materials and Methods

The present study assessed ED in HIV patients by various biophysical parameters as brachial artery FMD, CIMT, and proteinuria. A total of 43 HIV-infected patients were compared with 25 healthy controls who were healthy.

Results

Mean age of patients with HIV was 33.84 ± 5.61 years while that of healthy controls was 31.48 ± 5.40 years. Male to female ratio among cases was 24:19 while among controls was 17:8. Mean CIMT was significantly higher among cases than control (0.513 ± 0.079, 0.452 ± 0.050 mm, respectively, P = 0.001). Percentage change in FMD was significantly lower among cases than control (3.27 ± 2.01, 6.96 ± 1.28, respectively, P = 0.001). Urine protein grading was significantly different between cases and controls (P = 0.007), with stable HIV cases having significantly higher urine protein grading compared to healthy controls. However, no correlation was seen between CIMT, FMD, and proteinuria overall among cases and controls.

Conclusions

HIV-infected patients have significant impairment of endothelial function, in the form of increased CIMT, impaired FMD, and more proteinuria as compared to healthy controls.

Worsening endothelial function with efavirenz compared to protease inhibitors: a 12-month prospective study

OBJECTIVE

Changes in endothelial function, measured as flow-mediated dilation (FMD) of the brachial artery, has not been systematically assessed beyond 6 months of initiation of antiretroviral therapy (ART) when drug-related effects might offset initial improvements with virologic control.

DESIGN

We assessed 6 and 12 month changes in FMD [presented as median (quartile 1, quartile 3)] and circulating HIV and cardiovascular biomarkers in 23 subjects initiating ART.

RESULTS

There were no significant changes in FMD at 6 or 12 months overall despite significant increases in CD4 cell count and HDL-C and reductions in HIV RNA level, MCP-1, IP-10, sVCAM-1, sTNFR2, and sCD14. However, there were significant differences (P = 0.04) in the changes in FMD between those receiving efavirenz [N = 12; -3.50% (-4.90%, 0.68%)] vs. protease inhibitors at 12 months [N = 11; 1.50% (-0.86%, 4.56%)]. The differences in changes in FMD between those receiving and not receiving emtricitabine/tenofovir/efavirenz were more pronounced and were significantly different at both 6 and 12 months (P<0.02 for both). Additional studies showed no significant differences in changes in 25-(OH)-vitamin D, PTH, FGF-23, of F2-isoprostane levels between efavirenz and PI use or between those receiving and not receiving emtricitabine/tenofovir/efavirenz.

CONCLUSION

Efavirenz use was associated with reduced FMD at 12 months compared to PI-based regimens while emtricitabine/tenofovir/efavirenz was associated with reduced FMD at both 6 and 12 months compared to those not receiving this combination. Long-term effects of antiretrovirals on endothelial function may play an important role in the risk of cardiovascular disease in HIV-infected patients.

Neither proteinuria nor albuminuria is associated with endothelial dysfunction in HIV-infected patients without diabetes or hypertension

It is unknown whether systemic endothelial dysfunction underlies the association between nephropathy and cardiovascular disease (CVD) in persons infected with human immunodeficiency virus (HIV). Spot urine protein to creatinine ratio, spot urine albumin to creatinine ratio, creatinine clearance, estimated glomerular filtration rate, and flow-mediated dilation (FMD) of the brachial artery were evaluated in 123 study participants infected with HIV (58 receiving antiretroviral therapy [ART] and 65 not receiving ART) with no history of diabetes or hypertension. None of the renal markers, modeled as either continuous or categorical variables, correlated with FMD. Contrary to expectations, endothelial dysfunction may not be the link between nephropathy and CVD in HIV.

Endothelial, inflammatory, coagulation, metabolic effects and safety of etravirine in HIV-uninfected volunteers

The innate proatherosclerotic properties of non-nucleoside reverse transcriptase inhibitors have not previously been examined. Therefore, we performed a pilot study of etravirine (ETR) in healthy volunteers over 28 days. This investigation also allowed us to evaluate the safety of ETR over a period commonly used for HIV postexposure prophylaxis. ETR 200 mg twice daily was given to 28 healthy HIV-uninfected volunteers over 28 days. Flow-mediated dilation (FMD) of the brachial artery and circulating markers of inflammation, coagulation, and metabolism were measured at entry and at day 28. These circulating markers were also measured at day 35. Of the initial 28 subjects, 23 completed both entry and day 28 procedures. Two subjects were discontinued due to development of rash. No other major toxicities developed. The change in FMD over 28 days was minimal and not significant (0.03 [-3.21, 0.97] %; p=0.36). The post hoc estimated detectable absolute change in FMD with the 23 subjects in our study was 2.26%, which is an effect size that has been associated with future cardiovascular event rates in the general population; thus our study had sufficient power to find clinically relevant changes in FMD. In addition, there were no significant changes in any of the circulating markers from entry to day 28 or from day 28 to day 35. ETR did not demonstrate any innate proatherosclerotic properties over 28 days in these HIV-uninfected volunteers. ETR was generally well tolerated. Larger studies are warranted to confirm that ETR can be used safely as part of HIV postexposure prophylaxis regimens.

Relationship of body composition, metabolic status, antiretroviral use, and HIV disease factors to endothelial dysfunction in HIV-infected subjects

Vascular endothelial dysfunction may contribute to the increase in cardiovascular events during HIV-1 infection and its treatment. Antiretroviral therapy (ART), metabolic factors, lipodystrophy, and HIV infection itself may be involved. Ninety-six HIV-infected subjects were evaluated for endothelial function by measurement of brachial artery flow-mediated dilation (FMD) by ultrasound, single-slice CT of the abdomen and mid-thigh, whole-body dual x-ray absorptiomety (DXA) scans, and metabolic evaluations in a cross-sectional study. The median age was 40 years; 28% were female, 38% black, 3% Hispanic, and 59% white. Forty-nine (51%) were receiving ART, which included a PI in 28 (57%) and was non-PI based in 21 (43%). FMD (+/-SD) in subjects not on ART was 5.5 +/- 4.3%, PI-ART 5.3 +/- 3.6%, and non-PI-ART 5.5 +/- 4.1% (p = 0.9). Age, race, CD4 cell count, and HIV RNA did not correlate significantly with FMD. Among ART-treated subjects in the lowest tertile of thigh subcutaneous fat area (range 3-31 cm(2)), FMD was 4.4 +/- 3.5% and in the highest tertile (range 67-237 cm(2)) FMD was 6.8 +/- 3.6% (p = 0.07, t-test). However, in multivariate analyses, no body composition measure showed a significant association with FMD for either the group as a whole or in ART-treated subjects. ART use, PI use, CD4 cell count, and HIV RNA levels were not associated with endothelial dysfunction by brachial FMD. A definitive association with measures of adiposity was not detected in multivariate analysis, suggesting that lipoatrophy may not be an important contributor to endothelial dysfunction in HIV-infected individuals on ART.

Differential effects of HIV type 1 clade B and clade C Tat protein on expression of proinflammatory and antiinflammatory cytokines by primary monocytes

The existence of multiple subtypes of HIV-1 worldwide has created new challenges to control HIV-1 infection and associated neuropathogenesis. Previous studies indicate a difference in neuropathogenic manifestations of HIV-1-associated neuroAIDS between clade B- and clade C-infected subjects with clade B being more neuropathogenic than clade C. However, the exact mechanism underlying the differences in the neuropathogenesis by both the subtypes remains elusive. Development of neuroAIDS is associated with a complex interplay between proinflammatory and antiinflammatory cytokines and chemokines. In the current study, we hypothesize that HIV-1 clade B and C Tat protein exert differential effects on human primary monocytes leading to differences in gene and protein expression of cytokines implicated in neuroAIDS. Primary human monocytes were treated with clade B and clade C Tat protein and quantitative real time PCR was performed to determine gene expression of proinflammatory cytokines (IL-6 and TNF-alpha) and antiinflammatory cytokines (IL-4 and IL-10). Further, cytokine secretion was measured in culture supernatants by ELISA, whereas intracellular cytokine expression was detected by flow cytometry. Results indicate that monocytes treated with Tat B showed significant upregulation of proinflammatory cytokines, IL-6 and TNF-alpha, as compared to Tat C-treated cultures. However, expression of antiinflammatory molecules and IL-4 and IL-10 was found to be higher in Tat C-treated compared to Tat B-treated cultures. Thus, our result shows for the first time that Tat B and Tat C differentially modulate expression of neuropathogenic molecules that may be correlated with the differences in neuroAIDS manifestation induced by clade-specific infections.