The renal-bone axis in older people living with HIV on stable antiretroviral therapy: A sub-analysis of the GS-US-104-0423 study.

BACKGROUND: Data on low bone mineral density (BMD) in people living with HIV (PLWH) are mainly derived from younger adults; little is known about how antiretroviral therapy (ART) and alterations in the renal-bone axis relate to BMD in older PLWH. METHODS: Cross-sectional study of men > 50 years and post-menopausal women with HIV. Antiretroviral therapy exposure was stratified into four groups based on use of tenofovir disoproxil fumarate (TDF) and protease inhibitors (PI): non-TDF/non-PI, non-TDF/PI, TDF/non-PI, and TDF/PI. Bone mineral density was measured by dual X-ray absorptiometry (DXA). Bone turnover/regulatory markers and renal tubular function were analysed in stored plasma and urine samples. The association of ART exposure and bone/renal biomarkers on BMD was explored using logistic regression models. RESULTS: 247 individuals (median [IQR] age 57 [53, 65] years; 47% female; 13% of Black ethnicity; CD4 count 643 [473, 811] cells/mm3; and 98% with HIV RNA < 200 copies/mL) were included. Bone turnover and renal tubular function differed significantly by ART exposure. In analyses adjusted for demographic and traditional renal/bone risk factors, exposure to TDF and PI was associated with a fourfold greater risk of low BMD at the femoral neck and exposure to TDF and/or PI with a threefold greater risk of low BMD at the lumbar spine. The relationship between ART and low BMD was not altered by further adjustment for bone turnover or renal tubular function markers. CONCLUSIONS: The associations between low BMD and ART exposure (TDF vs. non-TDF and boosted vs. unboosted third agents) were minimally affected by adjustments for bone and kidney biomarkers.

Polypharmacy and drug-drug interactions in older and younger people living with HIV: the POPPY study.

BACKGROUND: Polypharmacy (use of ≥ five medications) increases the risk of drug-drug interactions and can lead to negative health outcomes. This study aimed to review the medications of people living with HIV (PLWH) and HIV-negative controls in the POPPY study and evaluate the frequency of polypharmacy and potential drug-drug interactions (PDDIs). METHODS: PDDIs between non-antiretroviral (ARV) drugs were analysed using the Lexicomp® database, and PDDIs between non-ARV and ARV drugs using the Liverpool drug interaction database. Between-group differences were assessed using χ2, Mann-Whitney U and Kruskal-Wallis tests. RESULTS: This analysis included 698 PLWH ≥50 years, 374 PLWH <50 years and 304 HIV-negative controls ≥50 years. The prevalence of polypharmacy was 65.8% in older PLWH, 48.1% in younger PLWH and 13.2% in the HIV-negative group. When ARVs were excluded, 29.8% of older PLWH and 14.2% of younger PLWH had polypharmacy. The prevalence of ≥1 PDDI involving non-ARV drugs was 36.1%, 20.3% and 16.4%, respectively, in older PLWH, younger PLWH and HIV-negative controls. In PLWH the prevalence of ≥1 PDDI involving ARV and non-ARV drugs was 57.3% in older PLWH and 32.4% in younger PLWH. CONCLUSIONS: Polypharmacy and PDDIs involving non-ARV/ARV drugs and non-ARV/non-ARV drugs were common among older PLWH, highlighting the need for increased awareness and additional research on all types of PDDI.

Fractures and the gut microbiome.

PURPOSE OF REVIEW: The role of the gut microbiome in the pathogenesis of several inflammatory, non-AIDS comorbidities, such as cardiovascular disease, cognitive impairment and liver disease has become a focus of recent research. Low bone mineral density (BMD) and increased fracture incidence in people living with HIV (PLWH) is also widely reported, however, the relationship between alterations in the gut microbiome and bone disease in PLWH has not been previously reviewed. RECENT FINDINGS: Murine models that manipulate the gut microbiome, either through breeding of 'germ-free' mice or antibiotic-depleted gut microbiome, show differences in bone mineral density and bone mass in those with altered gut microbiome. This effect is reported to be driven via changes in the gut-immune-skeletal axis, with changes favouring bone resorption. Several inflammatory conditions wherever bone loss is a prominent feature, such as rheumatoid arthritis and inflammatory bowel disease, have also reported alterations in the gut microbiome, which are associated with bone loss, again through changes in the gut-immune-skeletal axis. SUMMARY: The interplay between the gut microbiome and the immune-skeletal axis in HIV represents a complex relationship. Alterations in the gut microbiome, which induce an activated immune phenotype and inflammatory milieu are associated with non-AIDS comorbidities in PLWH and bone loss in several other conditions characterized by chronic immune activation and inflammation. It is, therefore, likely that there are comparable effects between altered gut microbiome and bone loss in HIV, however, further research is required to better define this relationship in populations of PLWH.

Metabolic profiles of individuals switched to second-line antiretroviral therapy after failing standard first-line therapy for treatment of HIV-1 infection in a randomized, controlled trial.

BACKGROUND: To investigate metabolic changes associated with second-line antiretroviral therapy (ART) following virological failure of first-line ART. METHODS: SECOND-LINE was an open-label randomized controlled trial. Participants were randomized 1:1 to receive ritonavir-boosted lopinavir (LPV/r) with 2-3 nucleoside/nucleotide reverse transcriptase inhibitors (N[t]RTI group) or raltegravir (RAL group). 210 participants had a dual energy X-ray absorptiometry (DXA)-scan at baseline, week 48 and 96. We categorized participants according to second-line ART backbone: thymidine analogue (ta-NRTI) + lamivudine/emtricitabine (3[F]TC; ta-NRTI group); tenofovir (TDF)+3(F)TC (TDF group); TDF+ta-NRTI ±3(F)TC (TDF+ta-NRTI group); RAL. Changes in fasted total cholesterol (TC), low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, TC/HDL-cholesterol ratio, triglycerides and glucose from baseline to week 96 were examined. We explored the association between metabolic and DXA-assessed soft-tissue changes. Linear regression methods were used. RESULTS: We analysed 454 participants. Participants in RAL group had greater TC increases, TC (adjusted mean difference [aMD]=0.65, 95% CI 0.33, 0.96), LDL-c (aMD=0.38, 95% CI 0.15, 0.61) and glucose (aMD=0.47, 95% CI -0.01, 0.92) compared to TDF group, and had greater increases in TC (aMD=0.65, 95% CI 0.28, 1.03), HDL-c (aMD=0.12, 95% CI 0.02, 0.23) and LDL-c (aMD=0.41, 95% CI 0.13, 0.69) compared to TDF+ta-NRTI group. TC/HDL ratio and triglycerides increased in all groups without significant differences between groups. A 1 kg increase in trunk fat mass was associated with an increase in TC. CONCLUSIONS: We observed metabolic changes of limited clinical significance in the relatively young population enrolled in this study. However, the metabolic changes observed may have greater clinical significance in older people living with HIV or those with other concomitant cardiovascular risks.

Experience of dolutegravir in HIV-infected treatment-naive patients from a tertiary care University Hospital in Ireland.

OBJECTIVE: Dolutegravir, an HIV integrase inhibitor, is a relatively new treatment option. To assess the tolerability, side effects, and time to viral decline to non-detectable in patients newly started on dolutegravir. METHODS: Retrospective health care record of 61 consecutive HIV treatment-naive patients started on dolutegravir was reviewed and analysed on SPSS. RESULTS: The mean initial viral load was 160826.05 copies/mL (range, 79-1,126,617 copies/mL). HIV viral load became non-detectable in 63.9% of patients on dolutegravir within 3 months. In all, 60.7% of patients reported no side effects on dolutegravir; 98.4% of the patients claimed full compliance to their antiretrovirals. CONCLUSION: Dolutegravir was found to be efficacious and well tolerated in HIV-infected treatment-naive patients.

Second European Round Table on the Future Management of HIV: 10-11 October 2014, Barcelona, Spain.

The Second European Round Table on the Future Management of HIV took place in Barcelona, 10-11 October 2014 and focused on the HIV-1 reservoir, strategies for HIV cure and primary HIV infection (PHI). Important issues in the HIV-1 reservoir research field are the validity of reservoir measurement techniques and the potential of new drugs to target latently infected cells. Current HIV-1 cure concepts are based on theoretical assumptions of biologically plausible mechanisms, supported by several clinical observations. Three main potential strategies are under investigation in order to achieve a sterilising cure or maintain HIV-1 remission: latency reversal resulting in antigen expression and viral cytolysis or immune targeted cell-death; immunological control of the reservoir; or replacement of the complete autologous haematopoietic and lymphoid stem-cell repertoire by transplantation. An interesting opportunity for restricting the size of the reservoir entails the early initiation of antiretroviral treatment (ART) during PHI. In terms of the reservoir, early treatment limits its size, alters its composition, and restricts the genetic variability of integrated proviral HIV-1 DNA. The challenges ahead involve the identification of patients undergoing seroconversion to HIV-1 and the prompt initiation of treatment. How the seemingly beneficial impact of early treatment will make cure more feasible, and whether the positive effects of the cure efforts outweigh the potentially negative impact of life-long ART, are important aspects of future collaborative research prospects.