Differences in neutralizing antibody sensitivities and envelope characteristics indicate distinct antigenic properties of Nigerian HIV-1 subtype G and CRF02_AG.

The magnitude of the HIV-1 epidemic in Nigeria is second only to the subtype C epidemic in South Africa, yet the subtypes prevalent in Nigeria require further characterization. A panel of 50 subtype G and 18 CRF02_AG Nigerian HIV-1 pseudoviruses (PSV) was developed and envelope coreceptor usage, neutralization sensitivity and cross-clade reactivity were characterized. These PSV were neutralized by some antibodies targeting major neutralizing determinants, but potentially important differences were observed in specific sensitivities (eg. to sCD4, MPER and V2/V3 monoclonal antibodies), as well as in properties such as variable loop lengths, number of potential N-linked glycans and charge, demonstrating distinct antigenic characteristics of CRF02_AG and subtype G. There was preferential neutralization of the matched CRF/subtype when PSV from subtype G or CRF02_AG were tested using pooled plasma. These novel Nigerian PSV will be useful to study HIV-1 CRF- or subtype-specific humoral immune responses for subtype G and CRF02_AG.

Limited emergence of resistance to integrase strand transfer inhibitors (INSTIs) in ART-experienced participants failing dolutegravir-based antiretroviral therapy: a cross-sectional analysis of a Northeast Nigerian cohort.

BACKGROUND: Due to the high prevalence of resistance to NNRTI-based ART since 2018, consolidated recommendations from the WHO have indicated dolutegravir as the preferred drug of choice for HIV treatment globally. There is a paucity of resistance outcome data from HIV-1 non-B subtypes circulating across West Africa. AIMS: We characterized the mutational profiles of persons living with HIV from a cross-sectional cohort in North-East Nigeria failing a dolutegravir-based ART regimen. METHODS: WGS of plasma samples collected from 61 HIV-1-infected participants following virological failure of dolutegravir-based ART were sequenced using the Illumina platform. Sequencing was successfully completed for samples from 55 participants. Following quality control, 33 full genomes were analysed from participants with a median age of 40 years and median time on ART of 9 years. HIV-1 subtyping was performed using SNAPPy. RESULTS: Most participants had mutational profiles reflective of exposure to previous first- and second-line ART regimens comprised NRTIs and NNRTIs. More than half of participants had one or more drug resistance-associated mutations (DRMs) affecting susceptibility to NRTIs (17/33; 52%) and NNRTIs (24/33; 73%). Almost a quarter of participants (8/33; 24.4%) had one or more DRMs affecting tenofovir susceptibility. Only one participant, infected with HIV-1 subtype G, had evidence of DRMs affecting dolutegravir susceptibility-this was characterized by the T66A, G118R, E138K and R263K mutations. CONCLUSIONS: This study found a low prevalence of resistance to dolutegravir; the data are therefore supportive of the continual rollout of dolutegravir as the primary first-line regimen for ART-naive participants and the preferred switch to second-line ART across the region. However, population-level, longer-term data collection on dolutegravir outcomes are required to further guide implementation and policy action across the region.

Determinants of Preexposure Prophylaxis Cascade Among Sexual and Gender Minorities in Nigeria.

BACKGROUND: Preexposure prophylaxis (PrEP) is effective in preventing human immunodeficiency virus (HIV) infection among sexual and gender minorities (SGMs). We evaluated the characteristics associated with engagement in 7 steps of the PrEP cascade among SGMs in Nigeria. METHODS: Sexual and gender minorities without HIV from the Abuja site of TRUST/RV368 cohort who were surveyed on awareness of and willingness to use PrEP were approached for PrEP initiation upon availability of oral daily PrEP. To understand gaps in the uptake of oral daily PrEP, we categorized the HIV PrEP cascade as (i) education about PrEP, (ii) interest in PrEP, (iii) successful contact, (iv) appointment scheduled, (v) appointment attendance, (vi) PrEP initiation, and (vii) plasma protective levels of tenofovir disoproxil fumarate. Multivariable logistic regression models were used to determine factors associated with each of the 7 steps in the HIV PrEP cascade. RESULTS: Of 788 participants, 718 (91.1%) showed interest in taking oral daily PrEP every day and/or after a sexual act, 542 (68.8%) were successfully contacted, 433 (54.9%) scheduled an appointment, 409 (51.9%) attended a scheduled appointment, 400 (50.8%) initiated oral daily PrEP, and 59 (7.4%) had protective levels of tenofovir disoproxil fumarate. Of initiators of PrEP, 23 (5.8%) seroconverted at a rate of 13.9 cases/100 person-years. Better social support, larger network density, and higher education were associated with engagement in 4 to 5 components of the cascade. CONCLUSIONS: Our data highlight a gap between willingness and actual PrEP use. Despite PrEP's effectiveness in preventing HIV, the optimal impact of PrEP for SGMs in sub-Saharan Africa will require multifaceted approaches that combine social support, education, and destigmatization.

The quality of life among men who have sex with men (MSM) living with and those not living with HIV in Abuja Nigeria.

Our objective was to assess factors associated with health-related quality of life (HRQoL) among men who have sex with men (MSM) living with or those not living with HIV in Nigeria. A cross-sectional subset of adult MSM in the ongoing TRUST/RV368 HIV prevention and treatment study were recruited and completed the World Health Organization quality of life in HIV infection (WHOQOL-BREF) questionnaire. The tool comprises physical health, psychological health, social relationships and environmental health domains from which scores were extracted. T-tests were used to compare mean HRQoL scores between participants living with or those not living with HIV and among persons living with HIV who had been on antiretroviral therapy for ≥1 year or <1 year. Of 322 study participants, 186 (57.8%) were living with HIV. The mean scores were significantly lower for participants living with HIV as compared to those not living with HIV in physical health, psychological health and social relationship domains. Among persons living with HIV and taking ART, scores were significantly lower for those whose duration was <1 year as compared to ≥1 year regarding physical health and psychological health. Strategies to improve HIV prevention and early detection and linkage to HIV care may improve HRQoL.

Prevalence and characteristics of metabolic syndrome and its components among adults living with and without HIV in Nigeria: a single-center study.

BACKGROUND: Persons living with HIV (PLHIV) now live longer due to effective combination antiretroviral therapy. However, emerging evidence indicates that they may be at increased risk for some cardiometabolic disorders. We compared the prevalence of metabolic syndrome (MetS) and its component disorders between persons living with and without HIV in Nigeria. METHODS: This was a cross-sectional analysis of baseline data from a prospective cohort study of non-communicable diseases among PLHIV along with age- and sex-matched persons without HIV (PWoH) at the University of Abuja Teaching Hospital Nigeria. We collected sociodemographic and clinical data, including anthropometric measures and results of relevant laboratory tests. MetS was defined using a modification of the third report of the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III) criteria. RESULTS: Of the 440 PLHIV and 232 PWoH, women constituted 50.5% and 51.3% respectively. The median age of the PLHIV was 45 years while that of the PWoH was 40 years. The prevalence of MetS was 30.7% (95% CI: 26.4%, 35.2%) and 22.8% (95% CI: 17.6%, 28.8%) among the PLHIV and PWoH respectively (P = 0.026). Independent associations were found for older age (P < 0.001), female sex (P < 0.001), family history of diabetes (P < 0.001), family history of hypertension (P = 0.013) and alcohol use (P = 0.015). The prevalence of component disorders for PLHIV versus PWoH were as follows: high blood pressure (22.3% vs 20.3%), prediabetes (33.8% vs 21.1%), diabetes (20.5% vs 8.2%), high triglycerides (24.5% vs 17.2%), low HDL-Cholesterol (51.1% vs 41.4%), and abdominal obesity (38.4% vs 37.1%). Adjusting for age and sex, prediabetes, diabetes, and low HDL-Cholesterol were significantly associated with HIV status. Duration on antiretroviral therapy, protease inhibitor-based regimen, CD4 count, and viral load were associated with some of the disorders mostly in unadjusted analyses. CONCLUSION: We found a high burden of MetS and its component disorders, with significantly higher prevalence of dysglycemia and dyslipidemia among PLHIV as compared to PWoH. Integration of strategies for the prevention and management of MetS disorders is needed in HIV treatment settings.

Prevalence of depression among people living with HIV in rural hospitals in South-Western Nigeria-Association with clinico-demographic factors.

Major depression is the most common neuropsychiatric disorder among people living with HIV (PLWH) and is predictive of high morbidity and mortality among them. This study estimated the prevalence and explored factors associated with depression among PLWH in two rural secondary health facilities providing anti-retroviral therapy (ART) services in Southwestern Nigeria between September and December 2020. The Patient Health Questionnaire-9 (PHQ-9) was used to screen and identify PLWH aged 18 years or older with depression. Descriptive statistics, bivariate and multivariate analyses were performed with SPSS version 23. A total of 172 respondents were screened. The prevalence of depression was 16.3% (95% CI 11.1%, 22.7%). Mild, moderate, and moderately severe depression was identified in 17 (9.9%), 8(4.7%) and 3(1.7%) of the participants, respectively. One (0.6%) respondent had suicidal ideation. Of PLWH with any depression, 20/28(71.4%) were within the 40-59 years of age range. None of the participants was on antidepressants. The factor most associated with depression was hypertension, with adjusted odd ratios of 9.8(95% CI 3.5-27.3, p < 0.0001). The study highlights the importance of screening for the severity of depression among PLWH in rural hospitals providing ART services in Africa. PLWH with comorbid hypertension were more likely to suffer from some form of depression.

Deep sequencing of HIV-1 reveals extensive subtype variation and drug resistance after failure of first-line antiretroviral regimens in Nigeria.

BACKGROUND: Deep sequencing could improve understanding of HIV treatment failure and viral population dynamics. However, this tool is often inaccessible in low- and middle-income countries. OBJECTIVES: To determine the genetic patterns of resistance emerging in West African HIV-1 subtypes during first-line virological failure, and the implications for future antiretroviral options. PATIENTS AND METHODS: Participants were selected from a Nigerian cohort of people living with HIV who had failed first-line ART and subsequently switched to second-line therapy. Whole HIV-1 genome sequences were generated from first-line virological failure samples with Illumina MiSeq. Mutations detected at ≥2% frequency were analysed and compared by subtype. RESULTS: HIV-1 sequences were obtained from 101 participants (65% female, median age 30 years, median 32.9 months of nevirapine- or efavirenz-based ART). Thymidine analogue mutations (TAMs) were detected in 61%, other core NRTI mutations in 92% and NNRTI mutations in 99%. Minority variants (<20% frequency) comprised 18% of all mutations. K65R was more prevalent in CRF02_AG than G subtypes (33% versus 7%; P = 0.002), and ≥3 TAMs were more common in G than CRF02_AG (52% versus 24%; P = 0.004). Subtype G viruses also contained more RT cleavage site mutations. Cross-resistance to at least one of the newer NNRTIs, doravirine, etravirine or rilpivirine, was predicted in 81% of participants. CONCLUSIONS: Extensive drug resistance had accumulated in people with West African HIV-1 subtypes, prior to second-line ART. Deep sequencing significantly increased the detection of resistance-associated mutations. Caution should be used if considering newer-generation NNRTI agents in this setting.

Individual and partnership characteristics associated with consistent condom use in a cohort of cisgender men who have sex with men and transgender women in Nigeria.

BACKGROUND: This study reports on the individual and partnership characteristics that influence consistent condom use in cisgender men who have sex with men (MSM) and transgender women (TGW) attending trusted community centers that provide HIV prevention and treatment services in Nigeria. METHODS: Adults assigned male at birth who reported anal sex with male partners who enrolled between March 2013-2019 and had information about at least one male sexual partner were included in these analyses. At enrollment and follow-up visits every 3 months for up to 18 months, participants were administered detailed questionnaires that collected information about demographics, sexual practices, HIV risk behaviors, and characteristics and behaviors of their partners in the previous year (at enrollment) or the preceding 3 to 6-months (at follow-up visits). Logistic regression models with generalized estimating equations were used to assess the odds ratio (OR) and 95% confidence intervals (CI) of individual, partner, and partnership characteristics associated with consistent condom use (CCU). A participant was defined as consistently using condom if they reported always using condoms all the time they had insertive, receptive or both types of anal sex with a male partner. RESULTS: At the individual level, CCU was positively associated with higher education, disclosure of key population status to a healthcare worker and negatively associated with poor access to condoms. At the partner and partnership level, CCU was associated with partners with higher education (aOR: 1.36; 95% CI: 1.07-1.72), casual relationships (aOR: 1.22; 95% CI: 1.11-1.34) and relationships in which partners encouraged the participant to use condoms with other partners (aOR: 1.14; 95% CI: 1.02-1.28). Relationships in which the partner was married to a woman and/or the partner's HIV status positive or unknown were negatively associated with CCU. CONCLUSIONS: These findings suggest that individuals in relationships where partners were more open and encouraged safer sex were more likely to consistently use condoms. HIV prevention programs should consider leveraging communication to sexual partners to encourage condom use as this may support condom use with other sexual partners. Given sustained and growing HIV and STI epidemics among MSM and TGW, even with pre-exposure prophylaxis scale-up, it is crucial to continue to study optimal implementation strategies to increase condom use.

Mycoplasma promotes malignant transformation in vivo, and its DnaK, a bacterial chaperone protein, has broad oncogenic properties.

We isolated a strain of human mycoplasma that promotes lymphomagenesis in SCID mice, pointing to a p53-dependent mechanism similar to lymphomagenesis in uninfected p53-/- SCID mice. Additionally, mycoplasma infection in vitro reduces p53 activity. Immunoprecipitation of p53 in mycoplasma-infected cells identified several mycoplasma proteins, including DnaK, a member of the Hsp70 chaperon family. We focused on DnaK because of its ability to interact with proteins. We demonstrate that mycoplasma DnaK interacts with and reduces the activities of human proteins involved in critical cellular pathways, including DNA-PK and PARP1, which are required for efficient DNA repair, and binds to USP10 (a key p53 regulator), impairing p53-dependent anticancer functions. This also reduced the efficacy of anticancer drugs that depend on p53 to exert their effect. mycoplasma was detected early in the infected mice, but only low copy numbers of mycoplasma DnaK DNA sequences were found in some primary and secondary tumors, pointing toward a hit-and-run/hide mechanism of transformation. Uninfected bystander cells took up exogenous DnaK, suggesting a possible paracrine function in promoting malignant transformation, over and above cells infected with the mycoplasma. Phylogenetic amino acid analysis shows that other bacteria associated with human cancers have similar DnaKs, consistent with a common mechanism of cellular transformation mediated through disruption of DNA-repair mechanisms, as well as p53 dysregulation, that also results in cancer-drug resistance. This suggests that the oncogenic properties of certain bacteria are DnaK-mediated.

Metabolic Changes in Chronic Hepatitis C Patients Who Carry IFNL4-ΔG and Achieve Sustained Virologic Response With Direct-Acting Antiviral Therapy.

BACKGROUND: Clearance of hepatitis C virus (HCV) results in rapid changes in metabolic parameters early in direct-acting antiviral (DAA) therapy. Long-term changes after sustained virologic response (SVR) remain unknown. METHODS: We investigated longitudinal changes in metabolic and inflammatory outcomes in chronic hepatitis C (CHC) patients: low-density lipoprotein (LDL), high-density lipoprotein, triglycerides, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) using a general linear model for repeated measurements at 5 clinical time points and by human immunodeficiency virus (HIV) coinfection and IFNL4 genotype. RESULTS: The mean LDL increased markedly during DAA therapy (pre-DAA, 86.6 to DAA, 107.4 mg/dL; P < .0001), but then it decreased to 97.7 mg/dL by post-SVR year 1 (P < .001 compared with DAA; P = .0013 compared with SVR). In patients who carry the IFNL4-ΔG allele, mean LDL increased during treatment, then decreased at post-SVR year 1; however, in patients with TT/TT, genotype did not change during and after DAA treatment. The mean ALT and AST normalized rapidly between pre-DAA and DAA, whereas only mean ALT continued to decrease until post-SVR. Metabolic and inflammatory outcomes were similar by HIV-coinfection status. CONCLUSIONS: Changes in LDL among CHC patients who achieved SVR differed by IFNL4 genotype, which implicates the interferon-λ4 protein in metabolic changes observed in HCV-infected patients.

Characterizing Cross-Culturally Relevant Metrics of Stigma Among Men Who Have Sex With Men Across 8 Sub-Saharan African Countries and the United States.

Overcoming stigma affecting gay, bisexual, and other men who have sex with men (MSM) is a foundational element of an effective response to the human immunodeficiency virus (HIV) pandemic. Quantifying the impact of stigma mitigation interventions necessitates improved measurement of stigma for MSM around the world. In this study, we explored the underlying factor structure and psychometric properties of 13 sexual behavior stigma items among 10,396 MSM across 8 sub-Saharan African countries and the United States using cross-sectional data collected between 2012 and 2016. Exploratory factor analyses were used to examine the number and composition of underlying stigma factors. A 3-factor model was found to be an adequate fit in all countries (root mean square error of approximation = 0.02-0.05; comparative fit index/Tucker-Lewis index = 0.97-1.00/0.94-1.00; standardized root mean square residual = 0.04-0.08), consisting of "stigma from family and friends," "anticipated health-care stigma," and "general social stigma," with internal consistency estimates across countries of α = 0.36-0.80, α = 0.72-0.93, and α = 0.51-0.79, respectively. The 3-factor model of sexual behavior stigma cut across social contexts among MSM in the 9 countries. These findings indicate commonalities in sexual behavior stigma affecting MSM across sub-Saharan Africa and the United States, which can facilitate efforts to track progress on global stigma mitigation interventions.

High prevalence of integrase mutation L74I in West African HIV-1 subtypes prior to integrase inhibitor treatment.

OBJECTIVES: HIV-1 integrase inhibitors are recommended as first-line therapy by WHO, though efficacy and resistance data for non-B subtypes are limited. Two recent trials have identified the integrase L74I mutation to be associated with integrase inhibitor treatment failure in HIV-1 non-B subtypes. We sought to define the prevalence of integrase resistance mutations, including L74I, in West Africa. METHODS: We studied a Nigerian cohort of recipients prior to and during receipt of second-line PI-based therapy, who were integrase inhibitor-naive. Illumina next-generation sequencing with target enrichment was used on stored plasma samples. Drug resistance was interpreted using the Stanford Resistance Database and the IAS-USA 2019 mutation lists. RESULTS: Of 115 individuals, 59.1% harboured CRF02_AG HIV-1 and 40.9% harboured subtype G HIV-1. Four participants had major IAS-USA integrase resistance-associated mutations detected at low levels (2%-5% frequency). Two had Q148K minority variants and two had R263K (one of whom also had L74I). L74I was detected in plasma samples at over 2% frequency in 40% (46/115). Twelve (26.1%) had low-level minority variants of between 2% and 20% of the viral population sampled. The remaining 34 (73.9%) had L74I present at >20% frequency. L74I was more common among those with subtype G infection (55.3%, 26/47) than those with CRF02_AG infection (29.4%, 20/68) (P = 0.005). CONCLUSIONS: HIV-1 subtypes circulating in West Africa appear to have very low prevalence of major integrase mutations, but significant prevalence of L74I. A combination of in vitro and clinical studies is warranted to understand the potential implications.

Cognitive Function Among Antiretroviral Treatment-Naive Individuals Infected With Human Immunodeficiency Virus Type 1 Subtype G Versus CRF02_AG in Nigeria.

Background: Human immunodeficiency virus type 1 (HIV-1) subtype has been shown to be associated with disease progression. We compared cognitive function between individuals infected with HIV-1 subtype G and CRF02_AG in Nigeria. Methods: For this cross-sectional study, samples were analyzed from 146 antiretroviral-naive participants. Genotypic analysis of plasma HIV RNA was performed by nested polymerase chain reaction of protease and reverse transcriptase genes, and sequences were aligned with curated HIV-1 subtype references. Cognitive status was determined using demographically adjusted T scores and global deficit score (GDS) obtained from a comprehensive neuropsychological test battery. Results: A total of 76 (52.1%) participants were infected with CRF02_AG, 48 (32.8%) with subtype G, and 22 (15.1%) with other HIV-1 strains. In a multivariable linear regression adjusting for plasma HIV RNA, CD4 count, and depression score, mean global T score was lower among subtype G-infected compared with CRF02_AG-infected participants (mean difference, -3.0 [95% confidence interval {CI}, -5.2, to -.7]; P = .011). Also, T scores were significantly lower among subtype G- than CRF02_AG-infected participants for the speed of information processing, executive function, and verbal fluency ability domains. Adjusting for similar variables in a logistic regression, the odds of global cognitive impairment (GDS ≥0.5) were 2.2 times higher among subtype G compared with CRF02_AG-infected participants (odds ratio, 2.2 [95% CI, .9-5.4]; P = .078). Conclusions: Cognitive performance was significantly worse among antiretroviral-naive individuals with HIV-1 subtype G vs CRF02_AG infection. Further studies are required to characterize the mechanistic basis for these differences.

Plasma HIV RNA level is associated with neurocognitive function among HIV-1-infected patients in Nigeria.

Plasma HIV RNA level has been shown to correlate with HIV disease progression, morbidity, and mortality. We examined the association between levels of plasma HIV RNA and cognitive function among patients in Nigeria. A total of 179 HIV-1-infected participants with available plasma HIV RNA results and followed longitudinally for up to 2 years were included in this study. Blood samples from participants were used for the measurement of plasma HIV RNA and CD4+ T cell count. Utilizing demographic and practice effect-adjusted T scores obtained from a seven-domain neuropsychological test battery, cognitive status was determined by the global deficit score (GDS) approach, with a GDS ≥ 0.5 indicating cognitive impairment. In a longitudinal multivariable linear regression analysis, adjusting for CD4 cell count, Beck's Depression Score, age, gender, years of education, and antiretroviral treatment status, global T scores decreased by 0.35 per log10 increase in plasma HIV RNA [p = 0.033]. Adjusting for the same variables in a multivariable logistic regression, the odds of neurocognitive impairment were 28% higher per log10 increase in plasma HIV RNA (OR 1.28 [95% CI 1.08, 1.51]; p = 0.005). There were statistically significant associations for the speed of information processing, executive, and verbal fluency domains in both linear and logistic regression analyses. We found a significant association between plasma HIV RNA levels and cognitive function in both baseline (cross-sectional) and longitudinal analyses. However, the latter was significantly attenuated due to weak association among antiretroviral-treated individuals.

The Synergistic Impact of Sexual Stigma and Psychosocial Well-Being on HIV Testing: A Mixed-Methods Study Among Nigerian Men who have Sex with Men.

Although sexual stigma has been linked to decreased HIV testing among men who have sex with men (MSM), mechanisms for this association are unclear. We evaluated the role of psychosocial well-being in connecting sexual stigma and HIV testing using an explanatory sequential mixed methods analysis of 25 qualitative and 1480 quantitative interviews with MSM enrolled in a prospective cohort study in Nigeria from March/2013-February/2016. Utilizing structural equation modeling, we found a synergistic negative association between sexual stigma and suicidal ideation on HIV testing. Qualitatively, prior stigma experiences often generated psychological distress and perceptions of feeling unsafe, which decreased willingness to seek services at general health facilities. MSM reported feeling safe at the MSM-friendly study clinic but still described a need for psychosocial support services. Addressing stigma and unmet mental health needs among Nigerian MSM has the potential to improve HIV testing uptake.

Sexual Stigma Patterns Among Nigerian Men Who Have Sex with Men and Their Link to HIV and Sexually Transmitted Infection Prevalence.

Sexual stigma facilitates the spread of HIV and sexually transmitted infections (STIs) but little is known about stigma affecting Nigerian men who have sex with men (MSM). We assessed patterns of sexual stigma across Nigerian MSM and their relationship to HIV and STIs. Data were collected from the TRUST/RV368 Study, a prospective cohort of 1480 Nigerian MSM enrolled from March 2013 to February 2016 using respondent driven sampling. Structural equation modeling was utilized to assess the association between stigma classes and HIV and STI prevalence, adjusting for participants' characteristics. A dose-response association was found between stigma class and HIV prevalence (27, 40, 55%, overall χ2 p < 0.001) and STI prevalence (15, 21, 24%, overall χ2 p = 0.011). These data suggest that stigma mitigation strategies, combined with increased engagement of MSM and retention in the HIV care continuum, need to be a component of interventions focused on reducing HIV transmission risks among MSM in Nigeria.

Peripheral blood lymphocyte HIV DNA levels correlate with HIV associated neurocognitive disorders in Nigeria.

Mononuclear cells play key roles in the pathogenic mechanisms leading to HIV-associated neurocognitive disorders (HANDs). We examined the association between HIV DNA within peripheral blood mononuclear cell (PBMC) subsets and HAND in Nigeria. PBMCs were collected at baseline from 36 antiretroviral naive participants. CD14+ cells and T&B lymphocyte fractions were isolated by, respectively, positive and negative magnetic bead separation. Total HIV DNA within CD14+ and T&B cells were separately quantified using real-time PCR assay targeting HIV LTR-gag and cell input numbers determined by CCR5 copies/sample. Utilizing demographically adjusted T scores obtained from a 7-domain neuropsychological test battery, cognitive status was determined by the global deficit score (GDS) approach, with a GDS of ≥0.5 indicating cognitive impairment. In a linear regression adjusting for plasma HIV RNA, CD4 and lymphocyte count, Beck's depression score, and years of education, there was 0.04 lower log10 HIV DNA copies within T&B lymphocytes per unit increase in global T score (p = 0.02). Adjusting for the same variables in a logistic regression, the odds of cognitive impairment were 6.2 times greater per log10 increase in HIV DNA within T&B lymphocytes (p = 0.048). The association between cognitive impairment and HIV DNA within CD14+ monocytes did not reach statistical significance. In this pretreatment cohort with mild cognitive dysfunction, we found a strong association between levels of HIV DNA within the lymphocyte subset and HAND independent of plasma HIV RNA. These findings likely reflect the neurologic impact of a larger HIV reservoir and active viral replication.

Sexual partner characteristics and incident rectal Neisseria gonorrhoeae and Chlamydia trachomatis infections among gay men and other men who have sex with men (MSM): a prospective cohort in Abuja and Lagos, Nigeria.

BACKGROUND: STIs including Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) potentiate HIV acquisition and transmission especially among gay men and other men who have sex with men (MSM). We investigated the influence of sexual network composition on incident rectal NG and/or CT infections among Nigerian MSM. METHODS: TRUST/RV368 is a cohort of MSM recruited using respondent-driven sampling at trusted community centres in Abuja and Lagos, Nigeria. MSM respondents (egos) provided STI risk factors and demographic information for up to five of their most recent sexual partners (alters) within their sexual networks. Egos were tested for HIV, NG and CT every 3 months. Log-binomial regression was used to assess associations between alter characteristics and incident NG and/or CT. RESULTS: Between March 2013 and October 2015, 492 MSM were longitudinally screened for STIs, of which 28.0% (n=138) were positive for incident rectal STI (61 NG only, 42 CT only and 35 NG and CT). Among egos, condom use was associated with STIs (half of the time vs never (adjusted risk ratio (aRR) 0.5; 95% CI 0.3 to 0.8), always/almost always vs never (aRR 0.7; 95% CI 0.5 to 1.0)). Incident STIs were associated with having a younger alter ≤19 versus 30 years (aRR 0.6; 95% CI 0.4 to 1.0), HIV infection (aRR 1.5; 95% CI 1.1 to 2.0) and engaging in sex under the influence of alcohol (aRR 1.4 95% CI 1.1 to 1.7) among regular alters and age ≤19 versus 30 years (aRR 0.3; 95% CI 0.2 to 0.6), HIV infection (aRR 1.4; 95% CI 1.1 to 1.8) and engaging in sex under the influence of alcohol (aRR 1.2 95% CI 1.0 to 1.4) among casual alters. CONCLUSIONS: Given the centrality of sexual partner characteristics as risks for incident STIs among Nigerian MSM, there is a need to move beyond individual interventions and syndromic surveillance and get 'out there' in the STI management.

Serosorting and Sexual Risk for HIV Infection at the Ego-Alter Dyadic Level: An Egocentric Sexual Network Study Among MSM in Nigeria.

The objective of this egocentric network study was to investigate engagement in serosorting by HIV status and risk for HIV between seroconcordant and serodiscordant ego-alter dyads. Respondent-driving sampling was used to recruit 433 Nigerian men who have sex with men (MSM) from 2013 to 2014. Participant (ego) characteristics and that of five sex partners (alters) were collected. Seroconcordancy was assessed at the ego level and for each dyad. Among 433 egos, 18 % were seroconcordant with all partners. Among 880 dyads where participants knew their HIV status, 226 (25.7 %) were seroconcordant, with 11.7 % of HIV positive dyads seroconcordant and 37.0 % of HIV negative dyads seroconcordant. Seroconcordant dyads reported fewer casual sex partners, less partner concurrency, and partners who had ever injected drugs, but condom use did not differ significantly. Serosorting may be a viable risk reduction strategy among Nigerian MSM, but awareness of and communication about HIV status should be increased. Future studies should assess serosorting on a partner-by-partner basis.

Elevated homocysteine levels may moderate and mediate the association between HIV and cognitive impairment among middle-aged and older adults in an underserved population in Baltimore, Maryland.

Background: In the antiretroviral therapy (ART) era, HIV-associated neurocognitive disorders (HAND) remain a considerable challenge for people with HIV, yet not all such disorders can be attributed to HIV alone. This study aimed to: (1) identify factors influencing neurocognitive impairment (NCI) utilizing the NIH Toolbox Cognition Battery (NIHTB-CB) as per the revised research criteria for HAND; (2) ascertain the moderating role of high homocysteine levels in the association between NCI and HIV; and (3) assess the mediating effect of elevated homocysteine levels on this association.Methods: We analyzed data from 788 adults (≥45 years) participating in a study on HIV-related comorbidities in underserved Baltimore communities, using NIHTB-CB to gauge neurocognitive performance. Special attention was given to results from the Dimensional Change Card Sort (DCCS) test within the executive function domain during causal mediation analysis.Results: Overall, HIV was not associated with NCI presence. However, HIV was associated with NCI among individuals with homocysteine >14 µmol/L. Furthermore, HIV was both directly and indirectly associated with NCI in DCCS test scores. Notably, the mediating role of elevated homocysteine in DCCS scores was only observable among individuals who had never used cocaine or had used it for ≤ 10 years, suggesting that extended cocaine use may have a substantial influence on cognitive performance.Conclusions: The findings from this study suggest elevated homocysteine levels may moderate and mediate the association between HIV and neurocognitive impairment.