High residual inflammation despite HIV viral suppression: Lessons learned from real-time adherence monitoring among people with HIV in Africa

Intersectional Stigma, Fear of Negative Evaluation, Depression, and ART Adherence Among Women Living with HIV Who Engage in Substance Use: A Latent Class Serial Mediation Analysis

Women Living with HIV (WLHIV) who use substances face stigma related to HIV and substance use (SU). The relationship between the intersection of these stigmas and adherence to antiretroviral therapy (ART), as well as the underlying mechanisms, remains poorly understood. This study aimed to examine the association between intersectional HIV and SU stigma and ART adherence, while also exploring the potential role of depression and fear of negative evaluation (FNE) by other people in explaining this association. We analyzed data from 409 WLHIV collected between April 2016 and April 2017, Using Multidimensional Latent Class Item Response Theory analysis. We identified five subgroups (i.e., latent classes [C]) of WLHIV with different combinations of experienced SU and HIV stigma levels: (C1) low HIV and SU stigma; (C2) moderate SU stigma; (C3) higher HIV and lower SU stigma; (C4) moderate HIV and high SU stigma; and (C5) high HIV and moderate SU stigma. Medication adherence differed significantly among these classes. Women in the class with moderate HIV and high SU stigma had lower adherence than other classes. A serial mediation analysis suggested that FNE and depression symptoms are mechanisms that contribute to explaining the differences in ART adherence among WLHIV who experience different combinations of intersectional HIV and SU stigma. We suggest that FNE is a key intervention target to attenuate the effect of intersectional stigma on depression symptoms and ART adherence, and ultimately improve health outcomes among WLHIV.

Accelerated aging in people living with HIV: The neuroimmune feedback model

People living with HIV (PLWH) experience earlier onset of aging-related comorbidities compared to their counterparts without HIV. This paper lays out a theoretical model to explain why PLWH experience accelerated aging. Briefly, the model is structured as follows. PLWH experience disproportionately heavy burdens of psychosocial stress across the life course. This psychosocial stress increases risks for depressive symptoms and problematic substance use. Depressive symptoms and problematic substance use interfere with long-term adherence to antiretroviral therapy (ART). Lower ART adherence, in turn, exacerbates the elevated systemic inflammation stemming from HIV infection. This inflammation increases risks for aging-related comorbidities. Systemic inflammation also reduces connectivity in the brain's central executive network (CEN), a large-scale brain network that is critical for coping with stressful circumstances. This reduced capacity for coping with stress leads to further increases in depressive symptoms and problematic substance use. Together, these changes form a neuroimmune feedback loop that amplifies the impact of psychosocial stress on aging-related comorbidities. In this paper, I review the existing evidence relevant to this model and highlight directions for future research.

Tenofovir diphosphate in dried blood spots and HIV-1 resistance in South Africa

BACKGROUND

Suboptimal antiretroviral (ART) adherence can lead to virologic failure with consequent HIV-1 resistance. Tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a powerful biomarker of cumulative adherence, predictive of future viremia. It has been associated with resistance in Persons With HIV (PWH) in South Africa and the US. We explored the relationship of TFV-DP concentrations with antiretroviral drug resistance at the time of treatment failure in SA.

METHODS

Adult PWH from health clinics in Cape Town, South Africa on efavirenz-based first-line ART containing tenofovir disoproxil fumarate (TDF) with an undetectable (< 50 copies/mL) HIV-1 viral load (VL) were prospectively enrolled in an observational cohort for 12 months. Monthly study visits included blood collection for HIV-1 VL and DBS for TFV-DP. The first confirmed viral breakthrough (VB) > 400 copies/mL triggered HIV-1 genotyping at the subsequent visit. An electronic adherence (EA) device monitored ART adherence in real-time, estimated as a percent for the 30-days prior to VB. Wilcoxon rank sum test was used to compare median [IQR] TFV-DP by genotype outcome.

RESULTS

Of 250 individuals, (n = 195, 78% women), 21 experienced VB, with a median of 5 [4;7] months on study, and a median EA of 33.3 [13.3;53.3]%. Demographic characteristics between those with and without VB were similar. Median VL at VB was 4.0 [3.2;4.5] log copies/mL. TFV-DP concentrations trended down towards the VB visit. Median TFV-DP concentrations were significantly higher in those HIV-1 genotype did not amplify due to being virally suppressed at the subsequent visit (n = 10; 380 [227-661] fmol/punch, p = 0.035; EA 45 [24.9; 59.2]%); than in those who were successfully genotyped with evidence of drug resistance (n = 5, 241 [150-247] fmol/punch, EA 20 [6.7;36.7]%) and in individuals who did not have resistance (n = 3, 39.9 [16.6; 93.9] fmol/punch; EA 33.3 [16-38]%). Three genotype collections were not done. Only non-nucleoside reverse transcriptase inhibitor-associated mutations were identified on resistance testing. (K103N, E138K, Y118H).

CONCLUSION

TFV-DP in DBS showed a step-wise inverse relationship with VB and drug resistance, with evidence of low cumulative ART adherence in PWH who developed antiretroviral resistance. Monitoring TFV-DP concentrations could be a valuable tool for predicting future VB and future resistance.

Comparing Predictive Ability of Two Objective Adherence Measures in a Community-Based Cohort on Antiretroviral Therapy in South Africa: Tenofovir Diphosphate Concentrations and Electronic Adherence Monitors

BACKGROUND

Electronic adherence (EA) and tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) are objective measures of antiretroviral therapy (ART) adherence. We characterized the association between these measures in a prospective cohort of persons with HIV (PWH) on ART.

SETTING

Four primary health clinics in Cape Town, South Africa.

METHODS

We enrolled 250 virally suppressed PWH receiving tenofovir-based ART. We collected EA data, monthly viral load, and TFV-DP in DBS for 12 months. We used logistic regression to estimate the adjusted odds ratio (aOR) and 95% confidence intervals (CIs) for future viral breakthrough (VB) (>400 copies/mL) for each adherence measure. Receiver operating characteristics (ROCs) provided the predictive power of these measures.

RESULTS

Participants had a median (IQR) age of 34 (27-42); 78% were women. Twenty-one (8%) developed VB. Logistic regression showed that when percent EA and TFV-DP concentrations increased, the odds of VB decreased. This relationship was consistent at the time of VB (aOR of 0.41 [95% CI: 0.25 to 0.66] for TFV-DP and aOR of 0.64 [95% CI: 0.54 to 0.76] for EA) and for up to 2 months before VB. Both adherence measures predicted future VB at both 1 month and 2 months before viral load measurement.

CONCLUSION

We established that 2 objective adherence measures, EA and TFV-DP in DBS, have a positive association with, and are both strongly predictive of, VB in a community-based South African cohort on ART. Future research is needed to determine the feasibility of implementing these adherence measures in resource-limited settings to facilitate adherence interventions.

Sex-specific associations between plasma interleukin-6 and depression in persons with and without HIV

Background

Persons with HIV (PWH) have both more frequent depression and higher levels of plasma inflammatory biomarkers compared to persons without HIV (PWoH). Inflammation and depressive symptoms are linked, including in PWH; however, it is unclear whether these associations differ by HIV serostatus and biological sex.

Methods

Six plasma inflammatory biomarkers were assessed using samples from PWH and PWoH who participated in six NIH-funded studies through the UCSD HIV Neurobehavioral Research Program (HNRP) from 2011 to 2019. Factor analysis was performed to identify intercorrelated groups of biomarkers. Factors and their components were then examined for relationships with Beck Depression Inventory-II (BDI-II) and modifying effects of sex or HIV serostatus using multivariable linear regression, adjusting for demographics, substance use diagnoses, and relevant co-morbidities.

Results

Participants included 150 PWH (age = 48.3 ± 13.1 yr; 88% biologically male) and 138 PWoH (age = 46.3 ± 15.9; 56% male). Two inflammatory factors were identified: Factor 1 loaded on interleukin-6 (IL-6), C-reactive protein (CRP), and D-dimer; Factor 2 loaded on interleukin-8, chemokine C-C ligand 2 (CCL2), and chemokine C-X-C ligand 10 (CXCL10). Sex modified the effect of Factor 1 on BDI-II, with a more positive association for men than women (p = 0.04). No significant association between Factor 2 and BDI-II was found. Of the biomarkers in Factor 1, only IL-6 was significantly associated with BDI-II and was modified by sex (p = 0.003). In sex-stratified analysis, a positive association was found for men (β = 5.42; 95% confidence interval = [1.32, 9.52]) but not women (β = -3.88; 95% C.I. = [-11.02, 3.26]). No HIV-related interactions were detected.

Interpretation

We identified a depression-associated inflammatory factor present in both PWH and PWoH, consistent with prior studies of PWH only. The association was driven by a correlation between IL-6 and depression exclusively in men, suggesting that the depression-inflammation link differs by sex. Future studies of depression etiology or treatment, including those on persons with HIV, should consider the impact of biological sex in both design and analysis.

Beyond Undetectable: Modeling the Clinical Benefit of Improved Antiretroviral Adherence in Persons With Human Immunodeficiency Virus With Virologic Suppression

Background

Incomplete antiretroviral therapy (ART) adherence has been linked to deleterious immunologic, inflammatory, and clinical consequences, even among virally suppressed (<50 copies/mL) persons with human immunodeficiency virus (PWH). The impact of improving adherence in the risk of severe non-AIDS events (SNAEs) and death in this population is unknown.

Methods

We estimated the reduction in the risk of SNAEs or death resulting from an increase in ART adherence by (1) applying existing data on the association between adherence with high residual inflammation/coagulopathy in virally suppressed PWH, and (2) using a Cox proportional hazards model derived from changes in plasma interleukin 6 (IL-6) and D-dimer from 3 randomized clinical trials. Comparatively, assuming 100% ART adherence in a PWH who achieves viral suppression, we estimated the number of persons in whom a decrease in adherence to <100% would need to be observed for an additional SNAE or death event to occur during 3- and 5-year follow-up.

Results

Increasing ART adherence to 100% in PWH who are suppressed on ART despite imperfect adherence translated into a 6%-37% reduction in the risk of SNAEs or death. Comparatively, based on an anticipated 12% increase in IL-6, 254 and 165 PWH would need to decrease their adherence from 100% to <100% for an additional event to occur over 3- and 5-year follow-up, respectively.

Conclusions

Modest gains in ART adherence could have clinical benefits beyond virologic suppression. Increasing ART adherence (eg, via an intervention or switch to long-acting ART) in PWH who remain virally suppressed despite incomplete adherence should be evaluated.