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Persons living with HIV in sero-discordant partnerships experience improved HIV care engagement compared with persons living with HIV in sero-concordant partnerships: a cross-sectional analysis of four African countries
Background
Persons living with HIV (PLWH) who are members of sero-discordant and sero-concordant relationships may experience psychological stressors or motivators that affect HIV care. We assessed the association between sero-discordance status, antiretroviral therapy (ART) uptake, and viral suppression in the African Cohort Study (AFRICOS).
Methods
AFRICOS enrolls PLWH and HIV-uninfected individuals at 12 sites in Uganda, Kenya, Tanzania, and Nigeria. At enrollment, we determined ART use through self-report. Viral suppression was defined as HIV RNA < 1000 copies/mL. We analyzed PLWH who were index participants within two types of sexual dyads: sero-discordant or sero-concordant. Binomial regression models were used to estimate prevalence ratios (PRs) and 95% confidence intervals (95% CIs) for factors associated with ART use and viral suppression at study enrollment.
Results
From January 2013 through March 2018, 223 index participants from sero-discordant dyads and 61 from sero-concordant dyads were enrolled. The majority of the indexes were aged 25–34 years (50.2%), female (53.4%), and married (96.5%). Sero-discordant indexes were more likely to disclose their status to partners compared with sero-concordant indexes (96.4% vs. 82.0%, p < 0.001). After adjustment, sero-discordant index participants were more likely to be on ART (aPR 2.8 [95% CI 1.1–6.8]), but no more likely to be virally suppressed. Results may be driven by unique psycho-social factors and global implementation of treatment as prevention.
Conclusions
PLWH in sero-discordant sexual partnerships demonstrated improved uptake of ART compared with those in sero-concordant partnerships. Interventions are needed to increase care engagement by individuals in sero-concordant relationships to improve HIV outcomes
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
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. 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. 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. 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.https://doi.org/10.1186/s12889-021-11275-
Evaluation of polygenic risk scores for breast and ovarian cancer risk prediction in BRCA1 and BRCA2 mutation carriers
Background: Genome-wide association studies (GWAS) have identified 94 common single-nucleotide polymorphisms (SNPs) associated with breast cancer (BC) risk and 18 associated with ovarian cancer (OC) risk. Several of these are also associated with risk of BC or OC for women who carry a pathogenic mutation in the high-risk BC and OC genes BRCA1 or BRCA2. The combined effects of these variants on BC or OC risk for BRCA1 and BRCA2 mutation carriers have not yet been assessed while their clinical management could benefit from improved personalized risk estimates.
Methods: We constructed polygenic risk scores (PRS) using BC and OC susceptibility SNPs identified through population-based GWAS: for BC (overall, estrogen receptor [ER]-positive, and ER-negative) and for OC. Using data from 15 252 female BRCA1 and 8211 BRCA2 carriers, the association of each PRS with BC or OC risk was evaluated using a weighted cohort approach, with time to diagnosis as the outcome and estimation of the hazard ratios (HRs) per standard deviation increase in the PRS.
Results: The PRS for ER-negative BC displayed the strongest association with BC risk in BRCA1 carriers (HR = 1.27, 95% confidence interval [CI] = 1.23 to 1.31, P = 8.2 x 10(53)). In BRCA2 carriers, the strongest association with BC risk was seen for the overall BC PRS (HR = 1.22, 95% CI = 1.17 to 1.28, P = 7.2 x 10(-20)). The OC PRS was strongly associated with OC risk for both BRCA1 and BRCA2 carriers. These translate to differences in absolute risks (more than 10% in each case) between the top and bottom deciles of the PRS distribution; for example, the OC risk was 6% by age 80 years for BRCA2 carriers at the 10th percentile of the OC PRS compared with 19% risk for those at the 90th percentile of PRS.
Conclusions: BC and OC PRS are predictive of cancer risk in BRCA1 and BRCA2 carriers. Incorporation of the PRS into risk prediction models has promise to better inform decisions on cancer risk management
BRCA2 polymorphic stop codon K3326X and the risk of breast, prostate, and ovarian cancers
Background: The K3326X variant in BRCA2 (BRCA2*c.9976A>T; p.Lys3326*; rs11571833) has been found to be associated with small increased risks of breast cancer. However, it is not clear to what extent linkage disequilibrium with fully pathogenic mutations might account for this association. There is scant information about the effect of K3326X in other hormone-related cancers.
Methods: Using weighted logistic regression, we analyzed data from the large iCOGS study including 76 637 cancer case patients and 83 796 control patients to estimate odds ratios (ORw) and 95% confidence intervals (CIs) for K3326X variant carriers in relation to breast, ovarian, and prostate cancer risks, with weights defined as probability of not having a pathogenic BRCA2 variant. Using Cox proportional hazards modeling, we also examined the associations of K3326X with breast and ovarian cancer risks among 7183 BRCA1 variant carriers. All statistical tests were two-sided.
Results: The K3326X variant was associated with breast (ORw = 1.28, 95% CI = 1.17 to 1.40, P = 5.9x10- 6) and invasive ovarian cancer (ORw = 1.26, 95% CI = 1.10 to 1.43, P = 3.8x10-3). These associations were stronger for serous ovarian cancer and for estrogen receptor–negative breast cancer (ORw = 1.46, 95% CI = 1.2 to 1.70, P = 3.4x10-5 and ORw = 1.50, 95% CI = 1.28 to 1.76, P = 4.1x10-5, respectively). For BRCA1 mutation carriers, there was a statistically significant inverse association of the K3326X variant with risk of ovarian cancer (HR = 0.43, 95% CI = 0.22 to 0.84, P = .013) but no association with breast cancer. No association with prostate cancer was observed.
Conclusions: Our study provides evidence that the K3326X variant is associated with risk of developing breast and ovarian cancers independent of other pathogenic variants in BRCA2. Further studies are needed to determine the biological mechanism of action responsible for these associations
Assessment of dietary diversity and nutritional support for children living with HIV in the IeDEA pediatric West African cohort: a non-comparative, feasibility study
BACKGROUND: Nutritional care is not optimally integrated into pediatric HIV care in sub-Saharan Africa. We assessed the 6-month effect of a nutritional support provided to children living with HIV, followed in a multicentric cohort in West Africa. METHODS: In 2014-2016, a nutritional intervention was carried out for children living with HIV, aged under 10 years, receiving antiretroviral therapy (ART) or not, in five HIV pediatric cohorts, in Benin, Togo and Côte d'Ivoire. Weight deficiency was assessed using two definitions: wasting (Weight for Height Z-score [WHZ] for children<5 years old or Body-Mass-Index for Age [BAZ] for ≥5 years) and underweight (Weight for Age Z-score [WAZ]) (WHO child growth standards). Combining these indicators, three categories of nutritional support were defined: 1/ children with severe malnutrition (WAZ and/or WHZ/BAZ <-3 Standard Deviations [SD]) were supported with Ready-To-Use Therapeutic Food (RUTF), 2/ those with moderate malnutrition (WAZ and/or WHZ/BAZ = [-3;-2[ SD) were supported with fortified blended flours produced locally in each country, 3/ those non malnourished (WAZ and WHZ/BAZ ≥-2 SD) received nutritional counselling only. Children were followed monthly over 6 months. Dietary Diversity Score (DDS) using a 24h recall was measured at the first and last visit of the intervention. RESULTS: Overall, 326 children were included, 48% were girls. At baseline, 66% were aged 5-10 years, 91% were on ART, and 17% were severely immunodeficient (CD4 <250 cells/mL or CD4%<15). Twenty-nine (9%) were severely malnourished, 63 (19%) moderately malnourished and 234 (72%) non-malnourished. After 6 months, 9/29 (31%) and 31/63 (48%) recovered from severe and moderate malnutrition respectively. The median DDS was 8 (IQR 7-9) in Côte d'Ivoire and Togo, 6 (IQR 6-7) in Benin. Mean DDS was 4.3/9 (sd 1.2) at first visit, with a lower score in Benin, but with no difference between first and last visit (p=0.907), nor by intervention groups (p-value=0.767). CONCLUSIONS: This intervention had a limited effect on nutritional recovery and dietary diversity improvement. Questions remain on determining appropriate nutritional products, in terms of adherence, proper use for families and adequate energy needs coverage for children living with HIV. TRIAL REGISTRATION: PACTR202001816232398 , June 01, 2020, retrospectively registered
Innate immune cell activation after HIV-1 vaccine administration is associated with increased antibody production
The RV144 Thai phase III clinical trial’s canarypox–protein HIV vaccine regimen showed modest efficacy in reducing infection. We therefore sought to determine the effects of vaccine administration on innate cell activation and subsequent associations with vaccine-induced immune responses. RV306 was a randomized, double-blind clinical trial in HIV-uninfected Thai adults that tested delayed boosting following the RV144 regimen. PBMC collected from RV306 participants prior to and 3 days after the last boost were used to investigate innate immune cell activation. Our analysis showed an increase in CD38+ mucosal associated invariant T (MAIT) cells, CD38+ invariant natural killer T (iNKT) cells, CD38+ γδ T cells, CD38+, CD69+ and HLA-DR+ NK cells 3 days after vaccine administration. An increase in CD14-CD16+ non-classical monocytes and CD14+CD16+ intermediate monocytes accompanied by a decrease in CD14+CD16- classical monocytes was also associated with vaccine administration. Inclusion of ALVAC-HIV in the boost did not further increase MAIT, iNKT, γδ T, and NK cell activation or increase the proportion of non-classical monocytes. Additionally, NK cell activation 3 days after vaccination was positively associated with antibody titers of HIV Env-specific total IgG and IgG1. Vδ1 T cell activation 3 days after vaccine administration was associated with HIV Env-specific IgG3 titers. Finally, we observed trending associations between MAIT cell activation and Env-specific IgG3 titers and between NK cell activation and TH023 pseudovirus neutralization titers. Our study identifies a potential role for innate cells, specifically NK, MAIT, and γδ T cells, in promoting antibody responses following HIV-1 vaccine administration
Safety, reactogenicity, and immunogenicity of a chimpanzee adenovirus vectored Ebola vaccine in adults in Africa: a randomised, observer-blind, placebo-controlled, phase 2 trial.
BACKGROUND: The 2014 Zaire Ebola virus disease epidemic accelerated vaccine development for the virus. We aimed to assess the safety, reactogenicity, and immunogenicity of one dose of monovalent, recombinant, chimpanzee adenovirus type-3 vectored Zaire Ebola glycoprotein vaccine (ChAd3-EBO-Z) in adults. METHODS: This phase 2, randomised, observer-blind, controlled trial was done in study centres in Cameroon, Mali, Nigeria, and Senegal. Healthy adults (≥18 years) were randomly assigned with a web-based system (1:1; minimisation procedure accounting for age, gender, centre) to receive ChAd3-EBO-Z (day 0), or saline placebo (day 0) and ChAd3-EBO-Z (month 6). The study was observer-blind until planned interim day 30 analysis, single-blind until month 6, and open-label after month 6 vaccination. Primary outcomes assessed in the total vaccinated cohort, which comprised all participants with at least one study dose administration documented, were serious adverse events (up to study end, month 12); and for a subcohort were solicited local or general adverse events (7 days post-vaccination), unsolicited adverse events (30 days post-vaccination), haematological or biochemical abnormalities, and clinical symptoms of thrombocytopenia (day 0-6). Secondary endpoints (subcohort; per-protocol cohort) evaluated anti-glycoprotein Ebola virus antibody titres (ELISA) pre-vaccination and 30 days post-vaccination. This study is registered with ClinicalTrials.gov, NCT02485301. FINDINGS: Between July 22, 2015, and Dec 10, 2015, 3030 adults were randomly assigned; 3013 were included in the total vaccinated cohort (1509 [50·1%] in the ChAd3-EBO-Z group and 1504 [49·9%] in the placebo/ChAd3-EBO-Z group), 17 were excluded because no vaccine was administered. The most common solicited injection site symptom was pain (356 [48%] of 748 in the ChAd3-EBO-Z group vs 57 [8%] of 751 in the placebo/ChAd3-EBO-Z group); the most common solicited general adverse event was headache (345 [46%] in the ChAd3-EBO-Z group vs 136 [18%] in the placebo/ChAd3-EBO-Z group). Unsolicited adverse events were reported by 123 (16%) of 749 in the ChAd3-EBO-Z group and 119 (16%) of 751 in the placebo/ChAd3-EBO-Z group. Serious adverse events were reported for 11 (1%) of 1509 adults in the ChAd3-EBO-Z group, and 18 (1%) of 1504 in the placebo/ChAd3-EBO-Z group; none were considered vaccination-related. No clinically meaningful thrombocytopenia was reported. At day 30, anti-glycoprotein Ebola virus antibody geometric mean concentration was 900 (95% CI 824-983) in the ChAd3-EBO-Z group. There were no treatment-related deaths. INTERPRETATION: ChAd3-EBO-Z was immunogenic and well tolerated in adults. Our findings provide a strong basis for future development steps, which should concentrate on multivalent approaches (including Sudan and Marburg strains). Additionally, prime-boost approaches should be a focus with a ChAd3-based vaccine for priming and boosted by a modified vaccinia Ankara-based vaccine. FUNDING: EU's Horizon 2020 research and innovation programme and GlaxoSmithKline Biologicals SA
Genome-wide association study identifies 32 novel breast cancer susceptibility loci from overall and subtype-specific analyses.
Breast cancer susceptibility variants frequently show heterogeneity in associations by tumor subtype1-3. To identify novel loci, we performed a genome-wide association study including 133,384 breast cancer cases and 113,789 controls, plus 18,908 BRCA1 mutation carriers (9,414 with breast cancer) of European ancestry, using both standard and novel methodologies that account for underlying tumor heterogeneity by estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status and tumor grade. We identified 32 novel susceptibility loci (P < 5.0 × 10-8), 15 of which showed evidence for associations with at least one tumor feature (false discovery rate < 0.05). Five loci showed associations (P < 0.05) in opposite directions between luminal and non-luminal subtypes. In silico analyses showed that these five loci contained cell-specific enhancers that differed between normal luminal and basal mammary cells. The genetic correlations between five intrinsic-like subtypes ranged from 0.35 to 0.80. The proportion of genome-wide chip heritability explained by all known susceptibility loci was 54.2% for luminal A-like disease and 37.6% for triple-negative disease. The odds ratios of polygenic risk scores, which included 330 variants, for the highest 1% of quantiles compared with middle quantiles were 5.63 and 3.02 for luminal A-like and triple-negative disease, respectively. These findings provide an improved understanding of genetic predisposition to breast cancer subtypes and will inform the development of subtype-specific polygenic risk scores
An original phylogenetic approach identified mitochondrial haplogroup T1a1 as inversely associated with breast cancer risk in BRCA2 mutation carriers
Introduction: Individuals carrying pathogenic mutations in the BRCA1 and BRCA2 genes have a high lifetime risk of breast cancer. BRCA1 and BRCA2 are involved in DNA double-strand break repair, DNA alterations that can be caused by exposure to reactive oxygen species, a main source of which are mitochondria. Mitochondrial genome variations affect electron transport chain efficiency and reactive oxygen species production. Individuals with different mitochondrial haplogroups differ in their metabolism and sensitivity to oxidative stress. Variability in mitochondrial genetic background can alter reactive oxygen species production, leading to cancer risk. In the present study, we tested the hypothesis that mitochondrial haplogroups modify breast cancer risk in BRCA1/2 mutation carriers. Methods: We genotyped 22,214 (11,421 affected, 10,793 unaffected) mutation carriers belonging to the Consortium of Investigators of Modifiers of BRCA1/2 for 129 mitochondrial polymorphisms using the iCOGS array. Haplogroup inference and association detection were performed using a phylogenetic approach. ALTree was applied to explore the reference mitochondrial evolutionary tree and detect subclades enriched in affected or unaffected individuals. Results: We discovered that subclade T1a1 was depleted in affected BRCA2 mutation carriers compared with the rest of clade T (hazard ratio (HR) = 0.55; 95% confidence interval (CI), 0.34 to 0.88; P = 0.01). Compared with the most frequent haplogroup in the general population (that is, H and T clades), the T1a1 haplogroup has a HR of 0.62 (95% CI, 0.40 to 0.95; P = 0.03). We also identified three potential susceptibility loci, including G13708A/rs28359178, which has demonstrated an inverse association with familial breast cancer risk. Conclusions: This study illustrates how original approaches such as the phylogeny-based method we used can empower classical molecular epidemiological studies aimed at identifying association or risk modification effects.Peer reviewe
Associations of common breast cancer susceptibility alleles with risk of breast cancer subtypes in BRCA1 and BRCA2 mutation carriers
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