High variance in quantification of Mycobacterium tuberculosis at low bacterial loads and with differentially detectable mycobacteria.

We examined the correlation between three different methods of Mycobacterium tuberculosis quantification: time to positivity (TTP), log10 CFU, and an assay to detect differentially detectable M. tuberculosis (DD Mtb) from three different prospective studies. Participants with DD Mtb have significantly more variation in the CFU/TTP correlation than participants with no DD Mtb (P < 0.001). This may impact the design of early bactericidal activity studies that use TTP as the primary outcome.

Spectrum of prevalent cardiovascular diseases in urban Port-au-Prince, Haiti: a population-based cross-sectional study.

Background: Eighty percent of global cardiovascular disease (CVD) is projected to occur in low- and middle -income countries (LMICs), yet local epidemiological data are scarce. We provide the first population-based, adjudicated CVD prevalence estimates in Port-au-Prince, Haiti to describe the spectrum of heart disease and investigate associated risk factors. Methods: Demographic, medical history, clinical, imaging and laboratory data were collected among adults recruited using multistage random sampling from 2019 to 2021. Prevalent CVD (heart failure, stroke, ischemic disease) were adjudicated using epidemiological criteria similar to international cohorts. Multivariable Poisson regressions assessed relationships between risk factors and prevalent CVD. Findings: Among 3003 participants, median age was 40 years, 58.1% were female, 70.2% reported income <1 USD/day, and all identified as Black Haitian. CVD age-adjusted prevalence was 14.7% (95% CI 13.3%, 16.5%), including heart failure (11.9% [95% CI 10.5%, 13.5%]), stroke (2.4% [95% CI 1.9%, 3.3%]), angina (2.1% [95% CI 1.6%, 2.9%]), myocardial infarction (1.0% [95% CI 0.6%, 1.8%]), and transient ischemic attack (0.4% [95% CI 0.2%, 1.0%]). Among participants with heart failure, median age was 57 years and 68.5% of cases were among women. The most common subtype was heart failure with preserved ejection fraction (80.4%). Heart failure was associated with hypertension, obesity, chronic kidney disease, depression, and stress. Interpretation: Early-onset heart failure prevalence is alarmingly high in urban Haiti and challenge modelling assumptions that ischemic heart disease and stroke dominate CVDs in LMICs. These data underscore the importance of local population-based epidemiologic data within LMICs to expedite the selection and implementation of evidence-based cardiovascular health policies targeting each country's spectrum of heart disease. Funding: This study was funded by NIH grants R01HL143788, D43TW011972, and K24HL163393, clinicaltrials.govNCT03892265.

Linkage Case Management and Posthospitalization Outcomes in People With HIV: The Daraja Randomized Clinical Trial.

Importance: Despite the widespread availability of antiretroviral therapy (ART), people with HIV still experience high mortality after hospital admission. Objective: To determine whether a linkage case management intervention (named "Daraja" ["bridge" in Kiswahili]) that was designed to address barriers to HIV care engagement could improve posthospital outcomes. Design, Setting, and Participants: Single-blind, individually randomized clinical trial to evaluate the effectiveness of the Daraja intervention. The study was conducted in 20 hospitals in Northwestern Tanzania. Five hundred people with HIV who were either not treated (ART-naive) or had discontinued ART and were hospitalized for any reason were enrolled between March 2019 and February 2022. Participants were randomly assigned 1:1 to receive either the Daraja intervention or enhanced standard care and were followed up for 12 months through March 2023. Intervention: The Daraja intervention group (n = 250) received up to 5 sessions conducted by a social worker at the hospital, in the home, and in the HIV clinic over a 3-month period. The enhanced standard care group (n = 250) received predischarge HIV counseling and assistance in scheduling an HIV clinic appointment. Main Outcomes and Measures: The primary outcome was all-cause mortality at 12 months after enrollment. Secondary outcomes related to HIV clinic attendance, ART use, and viral load suppression were extracted from HIV medical records. Antiretroviral therapy adherence was self-reported and pharmacy records confirmed perfect adherence. Results: The mean age was 37 (SD, 12) years, 76.8% were female, 35.0% had CD4 cell counts of less than 100/µL, and 80.4% were ART-naive. Intervention fidelity and uptake were high. A total of 85 participants (17.0%) died (43 in the intervention group; 42 in the enhanced standard care group); mortality did not differ by trial group (17.2% with intervention vs 16.8% with standard care; hazard ratio [HR], 1.01; 95% CI, 0.66-1.55; P = .96). The intervention, compared with enhanced standard care, reduced time to HIV clinic linkage (HR, 1.50; 95% CI, 1.24-1.82; P < .001) and ART initiation (HR, 1.56; 95% CI, 1.28-1.89; P < .001). Intervention participants also achieved higher rates of HIV clinic retention (87.4% vs 76.3%; P = .005), ART adherence (81.1% vs 67.6%; P = .002), and HIV viral load suppression (78.6% vs 67.1%; P = .01) at 12 months. The mean cost of the Daraja intervention was about US $22 per participant including startup costs. Conclusions and Relevance: Among hospitalized people with HIV, a linkage case management intervention did not reduce 12-month mortality outcomes. These findings may help inform decisions about the potential role of linkage case management among hospitalized people with HIV. Trial Registration: ClinicalTrials.gov Identifier: NCT03858998.

Circulating CD4+ T cells in people with HIV and history of pulmonary tuberculosis have more intact HIV DNA.

Background: The primary barrier to curing HIV infection is the pool of intact HIV proviruses integrated into host cell DNA throughout the bodies of people living with HIV (PLHIV), called the HIV reservoir. Reservoir size is impacted by the duration of HIV infection, delay in starting antiretroviral therapy (ART), and breakthrough viremia during ART. The leading infectious cause of death worldwide for PLHIV is TB, but we don't know how TB impacts the HIV reservoir. Methods: We designed a case-control study to compare HIV provirus-containing CD4 in PLHIV with vs. without a history of active TB disease. Study participants in the pilot and confirmatory cohort were enrolled at GHESKIO Centers in Port au Prince, Haiti. Intact and non-intact proviral DNA were quantified using droplet digital PCR of PBMC-derived CD4 cells. For a subset, Th1 and Th2 cytokines were assayed in plasma. Kruskal-Wallis tests were used to compare medians with tobit regression for censoring. Results: In the pilot cohort, we found that PLHIV with history of active pulmonary TB (n=20) had higher intact provirus than PLHIV without history of active TB (n=47) (794 vs 117 copies per million CD4, respectively; p<0.0001). In the confirmatory cohort, the quantity of intact provirus was higher in the TB group (n=13) compared with the non-TB group (n=18) (median 102 vs. 0 intact provirus per million CD4, respectively p=0.03). Additionally, we found that the frequencies of CD4+ T cells with any detectable proviral fragment was directly proportional to the levels of IL1B (p= 0.0025) and IL2 (p=0.0002). Conclusions: This is the first assessment of HIV provirus using IPDA in a clinical cohort from a resource limited setting, and the finding of larger reservoir in PLHIV with history of TB has significant implications for our understanding of TB-HIV coinfection and HIV cure efforts in TB-endemic settings.

The FLRT3-UNC5B checkpoint pathway inhibits T cell-based cancer immunotherapies.

Cancers exploit coinhibitory receptors on T cells to escape tumor immunity, and targeting such mechanisms has shown remarkable clinical benefit, but in a limited subset of patients. We hypothesized that cancer cells mimic noncanonical mechanisms of early development such as axon guidance pathways to evade T cell immunity. Using gain-of-function genetic screens, we profiled axon guidance proteins on human T cells and their cognate ligands and identified fibronectin leucine-rich transmembrane protein 3 (FLRT3) as a ligand that inhibits T cell activity. We demonstrated that FLRT3 inhibits T cells through UNC5B, an axon guidance receptor that is up-regulated on activated human T cells. FLRT3 expressed in human cancers favored tumor growth and inhibited CAR-T and BiTE + T cell killing and infiltration in humanized cancer models. An FLRT3 monoclonal antibody that blocked FLRT3-UNC5B interactions reversed these effects in an immune-dependent manner. This study supports the concept that axon guidance proteins mimic T cell checkpoints and can be targeted for cancer immunotherapy.

Commensal antimicrobial resistance mediates microbiome resilience to antibiotic disruption.

Despite their therapeutic benefits, antibiotics exert collateral damage on the microbiome and promote antimicrobial resistance. However, the mechanisms governing microbiome recovery from antibiotics are poorly understood. Treatment of Mycobacterium tuberculosis, the world's most common infection, represents the longest antimicrobial exposure in humans. Here, we investigate gut microbiome dynamics over 20 months of multidrug-resistant tuberculosis (TB) and 6 months of drug-sensitive TB treatment in humans. We find that gut microbiome dynamics and TB clearance are shared predictive cofactors of the resolution of TB-driven inflammation. The initial severe taxonomic and functional microbiome disruption, pathobiont domination, and enhancement of antibiotic resistance that initially accompanied long-term antibiotics were countered by later recovery of commensals. This resilience was driven by the competing evolution of antimicrobial resistance mutations in pathobionts and commensals, with commensal strains with resistance mutations reestablishing dominance. Fecal-microbiota transplantation of the antibiotic-resistant commensal microbiome in mice recapitulated resistance to further antibiotic disruption. These findings demonstrate that antimicrobial resistance mutations in commensals can have paradoxically beneficial effects by promoting microbiome resilience to antimicrobials and identify microbiome dynamics as a predictor of disease resolution in antibiotic therapy of a chronic infection.

A bedaquiline, pyrazinamide, levofloxacin, linezolid, clofazimine second line regimen for tuberculosis displays similar early bactericidal activity as the standard rifampin based first line regimen.

BACKGROUND: In 2018 the World Health Organization (WHO) recommended a switch to an all oral bedaquiline based second line regimen for treatment of drug resistant (DR) tuberculosis (TB). How these new second line regimens fare in comparison to first line regimens for treatment of drug sensitive (DS) tuberculosis is not well known. METHODS: In this study, we contemporaneously enrolled subjects with DS (n = 31) and DR (n = 23) TB and assessed their response to therapy with first-line (rifampin, isoniazid, ethambutol, pyrazinamide) or second-line (bedaquiline, pyrazinamide, levofloxacin, linezolid, clofazimine) regimens, respectively. RESULTS: We found that the early bactericidal activity of first and second line regimens was similar during the first two weeks of therapy as determined by BACTEC MGIT, colony forming units (CFU), and a liquid limiting dilution (LD) assays capable of detecting differentially detectable/culturable Mtb (DD Mtb). Further, an identical percentage (77.8%) of subjects from the DS and DR cohorts converted to culture negative after two months of therapy. CONCLUSIONS: Despite presenting with more advanced disease at time of treatment, subjects with DR TB receiving an all oral bedaquiline based second line treatment regimen displayed a similar microbiological response to therapy as subjects with DS TB receiving a first-line treatment regimen.

Prevalence and Severity of Chronic Kidney Disease in Haiti.

BACKGROUND: CKD is a major cause of morbidity and mortality in lower-income countries. However, population-based studies characterizing the epidemiology of CKD in these settings are lacking. The study objective was to describe the epidemiology of CKD in a population-based cohort in urban Haiti, including estimates of the prevalence by CKD stage, the magnitude of associated factors with CKD, and the proportion on guideline-recommended treatment. METHODS: We assessed the prevalence of CKD and associated risk factors in the population-based Haiti Cardiovascular Disease Cohort. We analyzed cross-sectional data from 2424 adults who completed a clinical examination, risk factor surveys, and laboratory measurements for serum creatinine, urinary albumin, and urinary creatinine. We compared our results with US estimates from the National Health and Nutrition Examination Survey. CKD was defined as either a reduced eGFR <60 ml/min per 1.73 m 2 or urinary albumin-to-creatinine ratio ≥30 mg/g according to the Kidney Disease Improving Global Outcomes guidelines. Multivariable logistic regression identified associated factors with CKD. RESULTS: The mean age was 42 years, 57% of participants were female, and 69% lived in extreme poverty on ≤1 US dollar per day. The age-standardized prevalence of CKD was 14% (95% confidence interval [CI], 12% to 15%). The age-standardized prevalence of reduced eGFR and elevated urinary albumin-to-creatinine ratio was 3% (95% CI, 2% to 4%) and 11% (95% CI, 10% to 13%), respectively. Diabetes (adjusted odds ratio, 4.1; 95% CI, 2.7 to 6.2) and hypertension (adjusted odds ratio, 2.9; 95% CI, 2.0 to 4.2) were significantly associated with CKD. Only 12% of participants with CKD and albuminuria were on guideline-recommended agents, such as angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers. CONCLUSIONS: In a large population-based cohort of Haitian adults, CKD was highly associated with both diabetes and hypertension. The proportion of participants with CKD on treatment was low, underscoring the need for strengthening clinical management and nephrology care health infrastructure in Haiti. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: A Longitudinal Cohort Study to Evaluate Cardiovascular Risk Factors and Disease in Haiti, NCT03892265 .

"Mobilizing our leaders": A multi-country qualitative study to increase the representation of women in global health leadership.

INTRODUCTION: Women play an essential role in health care delivery, and it is vital that they have equal representation in health leadership for equity, innovation, and the strengthening of health systems globally. Yet women remain vastly underrepresented in global health leadership positions, providing a clear example of the deeply rooted power imbalances that are central to the calls to decolonize global health. We conducted a multi-country study in Haiti, Tanzania, India, and the USA to examine gender-based challenges to career advancement for women in the global health workforce. Quantitative data on the type and prevalence of gender-based challenges has been previously reported. In this study, we analyze qualitative data collected through focus group discussions and in-depth interviews to understand women's experiences of gender-based obstacles to career advancement, their perceptions of underlying drivers, and perspectives on effective solutions. Guided by an adaptation of the Social Action Theory, we conducted focus group discussions and in-depth interviews with women at 4 major academic centers for clinical care and research in Haiti, India, Tanzania, and the United States. In total, 85 women participated in focus groups and 15 also participated in in-depth interviews. Discussions and interviews were conducted in the local language, by an experienced local facilitator unaffiliated with the participating institution, between 2017 and 2018. Discussions were recorded, transcribed, and translated. Data were analyzed by interpretive phenomenological methods for emergent themes. Three transcendent themes on gender-based challenges were identified: 1) cultural power imbalance, referring to the prevailing norms and engrained assumptions that women are less capable than men and that women's primary responsibility should be to their families; 2) institutional power imbalance, referring to the systematic gender bias upheld by existing leadership and power structures, and ranging from exclusion from career development opportunities to sexual harassment and assault; and 3) restricted agency, referring to women's limited ability to change their circumstances because of unequal cultural and institutional structures. Participants also described local, actionable solutions to address these barriers. These included: 1) formal reporting systems for sexual harassment and assault; 2) peer support and mentorship; and 3) accessible leadership training and mandatory gender equity training. Participants proposed feasible strategies to address gender-based challenges that could improve women's retention in health careers and foster their rise to leadership. Increasing the representation of women in global health leadership positions responds directly to efforts to decolonize global health and is integral to strengthening health systems and improving health outcomes for women and children worldwide.

High Dietary Sodium, Measured Using Spot Urine Samples, is Associated with Higher Blood Pressure among Young Adults in Haiti.

Background: Hypertension (HTN) is the leading cardiovascular disease (CVD) risk factor in Haiti and is likely driven by poverty-related social and dietary factors. Salt consumption in Haiti is hypothesized to be high but has never been rigorously quantified. Methods: We used spot urine samples from a subset of participants in the population-based Haiti Cardiovascular Disease Cohort to estimate population mean daily sodium intake. We compared three previously validated formulas for estimating dietary sodium intake using urine sodium, urine creatinine, age, sex, height, and weight. We explored the association between dietary sodium intake and blood pressure, stratified by age group. Results: A total of 1,240 participants had spot urine samples. Median age was 38 years (range 18-93), and 48% were female. The mean dietary sodium intake was 3.5-5.0 g/day across the three estimation methods, with 94.2%-97.9% of participants consuming above the World Health Organization (WHO) recommended maximum of 2 g/day of sodium. Among young adults aged 18-29, increasing salt intake from the lowest quartile of consumption (<3.73 g/day) to the highest quartile (>5.88 g/day) was associated with a mean 8.71 mmHg higher systolic blood pressure (SBP) (95% confidence interval: 3.35, 14.07; p = 0.001). An association was not seen in older age groups. Among participants under age 40, those with SBP ≥120 mmHg consumed 0.5 g/day more sodium than those with SBP <120 mmHg (95% confidence interval: 0.08, 0.69; p = 0.012). Conclusions: Nine out of 10 Haitian adults in our study population consumed more than the WHO recommended maximum for daily sodium intake. In young adults, higher sodium consumption was associated with higher SBP. This represents an inflection point for increased HTN risk early in the life course and points to dietary salt intake as a potential modifiable risk factor for primordial and primary CVD prevention in young adults.

Population-Based Epidemiology of Heart Failure in a Low-Income Country: The Haiti Cardiovascular Disease Cohort.

BACKGROUND: Cardiovascular disease disproportionately affects persons living in low- and middle-income countries and heart failure (HF) is thought to be a leading cause. Population-based studies characterizing the epidemiology of HF in these settings are lacking. We describe the age-standardized prevalence, survival, subtypes, risk factors, and 1-year mortality of HF in the population-based Haiti Cardiovascular Disease Cohort. METHODS: Participants were recruited using multistage cluster-area random sampling in Port-au-Prince, Haiti. A total of 2981 completed standardized history and exam, laboratory measures, and cardiac imaging. Clinical HF was defined by Framingham criteria. Kaplan-Meier and Cox proportional hazard regression assessed mortality among participants with and without HF; logistic regression identified associated factors. RESULTS: Among all participants, the median age was 40 years (interquartile range, 27-55), and 58.2% were female. Median follow-up was 15.4 months (interquartile range, 9-22). The age-standardized HF prevalence was 3.2% (93/2981 [95% CI, 2.6-3.9]). The average age of participants with HF was 57 years (interquartile range, 45-65), and 67.7% were female. The first significant increase in HF prevalence occurred between 30 to 39 and 40 to 49 years (1.1% versus 3.7%, P=0.003). HF with preserved ejection fraction was the most common HF subtype (71.0%). Age (adjusted odds ratio, 1.36 [1.12-1.66] per 10-year increase), hypertension (2.14 [1.26-3.66]), obesity (3.35 [95% CI, 1.99-5.62]), poverty (2.10 [1.18-3.72]), and renal dysfunction (5.42 [2.94-9.98]) were associated with HF. One-year HF mortality was 6.6% versus 0.8% (hazard ratio, 7.7 [95% CI, 2.9-20.6]; P<0.0001). CONCLUSIONS: The age-standardized prevalence of HF in this low-income setting was alarmingly high at 3.2%-5-fold higher than modeling estimates for low- and middle-income countries. Adults with HF were two decades younger and 7.7× more likely to die at 1 year compared with those in the community without HF. Further research characterizing the population burden of HF in low- and middle-income countries can guide resource allocation and development of pragmatic HF prevention and treatment interventions, ultimately reducing global cardiovascular disease health disparities. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03892265.

Transcriptional Biomarkers of Differentially Detectable Mycobacterium tuberculosis in Patient Sputum.

Certain populations of Mycobacterium tuberculosis go undetected by standard diagnostics but can be enumerated using limiting dilution assays. These differentially detectable M. tuberculosis (DD M. tuberculosis) populations may have relevance for persistence due to their drug tolerance. It is unclear how well DD M. tuberculosis from patients is modeled by a recently developed in vitro model in which M. tuberculosis starved in phosphate-buffered saline is incubated with rifampin to produce DD M. tuberculosis (the PBS-RIF model). This study attempted to answer this question. We selected 14 genes that displayed differential expression in the PBS-RIF model and evaluated their expression in patient sputa containing various proportions of DD M. tuberculosis. The expression of 12/14 genes correlated with the relative abundance of DD M. tuberculosis in patient sputa. Culture filtrate (CF), which promotes recovery of DD M. tuberculosis from certain patient sputa, improved these correlations in most cases. The gene whose reduced expression relative to M. tuberculosis 16S rRNA showed the greatest association with the presence and relative abundance of DD M. tuberculosis in patient sputa, icl1, was recently shown to play a functional role in restraining DD M. tuberculosis formation in the PBS-RIF model. Expression of icl1, combined with two additional DD M. tuberculosis-related genes, showed strong performance for predicting the presence or absence of DD M. tuberculosis in patient sputa (receiver operating characteristic [ROC] area under the curve [AUC] = 0.88). Thus, the in vitro DD M. tuberculosis model developed by Saito et al. (K. Saito, T. Warrier, S. Somersan-Karakaya, L. Kaminski, et al., Proc Natl Acad Sci U S A 114:E4832-E4840, 2017, https://doi.org/10.1073/pnas.1705385114) bears a resemblance to DD M. tuberculosis found in tuberculosis (TB) patients, and DD M. tuberculosis transcriptional profiles may be useful for monitoring DD M. tuberculosis populations in patient sputum. IMPORTANCE Differentially detectable M. tuberculosis (DD M. tuberculosis), which is detectable by limiting dilution assays but not by CFU, is present and enriched for in TB patient sputum after initiation of first-line therapy. These cryptic cells may play a role in disease persistence due to their phenotypic tolerance to anti-TB drugs. A recently developed in vitro model of DD M. tuberculosis (the PBS-RIF model) has expanded our understanding of these cells, though how well it translates to DD M. tuberculosis in patients is currently unknown. To answer this question, we selected 14 genes that displayed differential expression in the PBS-RIF model and evaluated their expression in TB patient sputa. We found that 12/14 of these genes showed a similar expression profile in patient sputa that correlated with the relative abundance of DD M. tuberculosis. Further, the expression of three of these genes showed strong performance for predicting the presence or absence of DD M. tuberculosis in patient sputa. The use of DD M. tuberculosis transcriptional profiles may allow for easier monitoring of DD M. tuberculosis populations in patient sputum in comparison to limiting dilution assays.

Extreme Food Insecurity and Malnutrition in Haiti: Findings from a Population-Based Cohort in Port-au-Prince, Haiti.

Haiti is one of the most food-insecure (FIS) nations in the world, with increasing rates of overweight and obesity. This study aimed to characterize FIS among households in urban Haiti and assess the relationship between FIS and body mass index (BMI) using enrollment data from the Haiti Cardiovascular Disease Cohort Study. FIS was characterized as no/low, moderate/high, and extreme based on the Household Food Security Scale. Multinomial logistic generalized estimating equations were used to evaluate the association between FIS categories and BMI, with obesity defined as BMI ≥ 30 kg/m2. Among 2972 participants, the prevalence of moderate/high FIS was 40.1% and extreme FIS was 43.7%. Those with extreme FIS had higher median age (41 vs. 38 years) and were less educated (secondary education: 11.6% vs. 20.3%) compared to those with no/low FIS. Although all FIS categories had high obesity prevalence, those with extreme FIS compared to no/low FIS (15.3% vs. 21.6%) had the lowest prevalence. Multivariable models showed an inverse relationship between FIS and obesity: moderate/high FIS (OR: 0.77, 95% CI: 0.56, 1.08) and extreme FIS (OR: 0.58, 95% CI: 0.42, 0.81) versus no/low FIS were associated with lower adjusted odds of obesity. We found high prevalence of extreme FIS in urban Haiti in a transitioning nutrition setting. The inverse relationship between extreme FIS and obesity needs to be further studied to reduce both FIS and obesity in this population.

The free fatty acid-binding pocket is a conserved hallmark in pathogenic ß-coronavirus spike proteins from SARS-CoV to Omicron.

As coronavirus disease 2019 (COVID-19) persists, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) emerge, accumulating spike (S) glycoprotein mutations. S receptor binding domain (RBD) comprises a free fatty acid (FFA)-binding pocket. FFA binding stabilizes a locked S conformation, interfering with virus infectivity. We provide evidence that the pocket is conserved in pathogenic ß-coronaviruses (ß-CoVs) infecting humans. SARS-CoV, MERS-CoV, SARS-CoV-2, and VOCs bind the essential FFA linoleic acid (LA), while binding is abolished by one mutation in common cold-causing HCoV-HKU1. In the SARS-CoV S structure, LA stabilizes the locked conformation, while the open, infectious conformation is devoid of LA. Electron tomography of SARS-CoV-2-infected cells reveals that LA treatment inhibits viral replication, resulting in fewer deformed virions. Our results establish FFA binding as a hallmark of pathogenic ß-CoV infection and replication, setting the stage for FFA-based antiviral strategies to overcome COVID-19.

High prevalence of obesity among women in urban Haiti: Findings from a population-based cohort.

Introduction: Obesity is associated with increased risk of non-communicable diseases and death and is increasing rapidly in low- and middle-income countries, including Haiti. There is limited population-based data on body mass index (BMI) and waist circumference (WC) and associated risk factors in Haiti. This study describes BMI and WC, and factors associated with obesity using a population-based cohort from Port-au-Prince. Methods: Baseline sociodemographic and clinical data were collected from participants in the Haiti CVD Cohort Study between March 2019 and August 2021. Weight was categorized by BMI (kg/m2) with obesity defined as ≥30 kg/m2. Abdominal obesity was defined using WC cutoffs of ≥80 cm for women and ≥94 cm for men based on WHO guidelines. Sociodemographic and behavioral risk factors, including age, sex, educational attainment, income, smoking status, physical activity, fat/oil use, daily fruit/vegetable consumption, and frequency of fried food intake were assessed for their association with obesity using a Poisson multivariable regression. Results: Among 2,966 participants, median age was 41 years (IQR: 28-55) and 57.6% were women. Median BMI was 24.0 kg/m2 (IQR: 20.9-28.1) and 508 (17.1%) participants were obese. Women represented 89.2% of the population with BMI ≥30 kg/m2. A total of 1,167 (68.3%) women had WC ≥80 cm and 144 (11.4%) men had WC ≥94 cm. BMI ≥30 kg/m2 was significantly more prevalent among women than men [PR 5.7; 95% CI: (4.3-7.6)], those 40-49 years compared to 18-29 years [PR 3.3; 95% CI: (2.4-4.6)], and those with income >10 USD per day compared to ≤1 USD [PR 1.3; 95% CI: (1.0-1.6)]. There were no significant associations with other health and behavioral risk factors. Discussion: In Haiti, women have an alarming 6-fold higher obesity prevalence compared to men (26.5 vs. 4.3%) and 89.2% of participants with obesity were women. Abdominal obesity was high, at 44.3%. Haiti faces a paradox of an ongoing national food insecurity crises and a burgeoning obesity epidemic. Individual, social, and environmental drivers of obesity, especially among women, need to be identified.

An optimized method for purifying, detecting and quantifying Mycobacterium tuberculosis RNA from sputum for monitoring treatment response in TB patients.

Diagnostics that more accurately detect and quantify viable Mycobacterium tuberculosis (Mtb) in the sputum of patients undergoing therapy are needed. Current culture- and molecular-based tests have shown limited efficacy for monitoring treatment response in TB patients, either due to the presence of viable sub-populations of Mtb which fail to grow under standard culture conditions (termed differentially detectable/culturable Mtb, DD Mtb) or the prolonged half-life of Mtb DNA in sputum. Here, we report an optimized RNA-based method for detecting and quantifying viable Mtb from patient sputum during the course of therapy. We first empirically derived a novel RNA extraction protocol from sputum that improves recovery of Mtb RNA while almost completely eliminating contamination from Mtb DNA and host nucleic acids. Next, we identified five Mtb 16S rRNA primer sets with varying limits of detection that were capable of distinguishing between live versus dead H37Rv Mtb. This combined protocol was then tested on sputa from a longitudinal cohort of patients receiving therapy for drug sensitive (DS) or drug resistant (DR) TB with first-line or second-line regimens, respectively. Results were compared with that of culture, including CFU, BACTEC MGIT, and a limiting dilution assay capable of detecting DD Mtb. The five 16S rRNA primer sets positively identified nearly all (range 94-100%) culture positive sputa, and a portion (19-37%) of culture negative sputa. In comparison, ten highly expressed Mtb mRNAs showed positivity in 72-86% of culture positive sputa, and in 0-13% of culture negative sputa. Two of the five 16S rRNA primer sets were able to positively identify 100% of culture positive sputa, and when tested on culture negative sputa from the DS cohort at 2 months post-initiation of therapy, identified 40% of samples as positive; a percentage that is in line with expected treatment failure rates when first-line therapy is discontinued early. These two primer sets also detected 16S rRNA in 13-20% of sputa at 6 months post-initiation of therapy in the DR cohort. Cycle threshold values for 16S rRNA showed a strong correlation with Mtb numbers as determined by culture (R > 0.87), including as Mtb numbers declined during the course of treatment with first-line and second-line regimens. The optimized molecular assay outlined here may have utility for monitoring treatment response in TB patients.

The Association of Gestational Diabetes with HIV Infection and Tuberculosis in Indian Women.

Infection of HIV is associated with an increased diabetes risk, which also increases tuberculosis risk. It is unknown if similar associations exist with gestational diabetes (GDM). We screened pregnant women living with and without HIV for GDM using oral glucose tolerance testing. In a subgroup of women with latent tuberculosis (positive interferon-gamma [IFN-γ] release assay), we used supernatants from tuberculosis antigen tubes to compare cytokine levels from women with and without GDM, matched by age and HIV status. Of 234 women, 21 (9%) had GDM, 13.9% living with HIV, and 6.5% without HIV (P = 0.06). Compared with women without GDM, women with GDM had lower median IFN-γ (19.1 versus 141.9 pg/mL, P = 0.03) and interleukin-2 (18.7 versus 249 pg/mL, P < 0.01). Our study suggests that HIV infection is associated with an increased risk of GDM, which is associated with decreased Mycobacterium tuberculosis immune responses. Gestational diabetes screening should be prioritized in tuberculosis-endemic countries, especially in women living with HIV.

Dietary Risk Factors for Cardiovascular Disease among Low-Income Haitian Adults: Findings from a Population-Based Cohort.

Poor diets are responsible for a large burden of noncommunicable disease (NCD). The prevalence of modifiable dietary risk factors is rising in lower-income countries such as Haiti, along with increasing urbanization and shifts to diets high in sugar, salt, and fat. We describe self-reported dietary patterns (intake of fruits, vegetables, fried food, sugar-sweetened beverages, and added salt and oil) among a population-based cohort of low-income adults in Port-au-Prince and assess for associated sociodemographic factors (age, sex, income, education, body mass index). Among 2989 participants, the median age was 40 years, and 58.0% were women. Less than 1% met the World Health Organization recommendation of at least five servings/day of fruits and vegetables. Participants consumed fried food on average 1.6 days/week and sugar-sweetened beverages on average 4.7 days/week; young males of low socioeconomic status were the most likely to consume these dietary risk factors. The vast majority of participants reported usually or often consuming salt (87.1%) and oil (86.5%) added to their meals eaten at home. Our findings underscore the need for public health campaigns, particularly those targeting young males and household cooks preparing family meals at home, to improve dietary patterns in Haiti in order to address the growing NCD burden.

Single-Cell Transcriptional Profiling Reveals Signatures of Helper, Effector, and Regulatory MAIT Cells during Homeostasis and Activation.

Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that recognize microbial vitamin B metabolites and have emerging roles in infectious disease, autoimmunity, and cancer. Although MAIT cells are identified by a semi-invariant TCR, their phenotypic and functional heterogeneity is not well understood. Here we present an integrated single cell transcriptomic analysis of over 76,000 human MAIT cells during early and prolonged Ag-specific activation with the MR1 ligand 5-OP-RU and nonspecific TCR stimulation. We show that MAIT cells span a broad range of homeostatic, effector, helper, tissue-infiltrating, regulatory, and exhausted phenotypes, with distinct gene expression programs associated with CD4+ or CD8+ coexpression. During early activation, MAIT cells rapidly adopt a cytotoxic phenotype characterized by high expression of GZMB, IFNG and TNF In contrast, prolonged stimulation induces heterogeneous states defined by proliferation, cytotoxicity, immune modulation, and exhaustion. We further demonstrate a FOXP3 expressing MAIT cell subset that phenotypically resembles conventional regulatory T cells. Moreover, scRNAseq-defined MAIT cell subpopulations were also detected in individuals recently exposed to Mycobacterium tuberculosis, confirming their presence during human infection. To our knowledge, our study provides the first comprehensive atlas of human MAIT cells in activation conditions and defines substantial functional heterogeneity, suggesting complex roles in health and disease.

Estimated blood pressure trajectories and hypertension patterns among pregnant women living with HIV, Haiti, 2007-2017.

Hypertension in pregnancy is a key driver of mortality and morbidity among Haitian women. HIV infection and treatment may worsen hypertension and increase cardiovascular disease risk. The authors examined blood pressure and hypertension patterns among 1965 women (2306 pregnancies ending in live births) in a prevention of maternal-to-child transmission (PMTCT) program in Port-au-Prince, Haiti, between 2007 and 2017. Hypertension was defined as blood pressure ≥140/90 mm Hg on two consecutive visits. Latent class analysis assessed trajectories of mean arterial pressure (MAP) and multinomial ordinal logistic regression examined factors associated with higher trajectories. Between 2007-2009 and 2013-2016, hypertension at PMTCT entry increased from 1.3% to 3.8% (p = .005), while incidence at any time during PMTCT follow-up increased from 5.0 to 16.1 per 100 person-years (p < .001). Hypertension detected ≤20 weeks and > 20 weeks of gestation (possible gestational hypertension) increased from 1.1% to 3.5% (p = .003) and from 2.3% to 6.9% (p < .001), respectively. Five MAP trajectories ranged from low-stable to high-increasing. In multivariable analysis controlling for history of antiretroviral therapy, age, parity, and weight, program entry in more recent years was associated with greater odds of higher MAP trajectory (adjusted odds ratio for 2013-2016 vs. 2007-2009 = 3.1, 95% confidence interval: 1.7-5.6). The increasing prevalence and incidence of hypertension highlight a need for screening and management prior to PMTCT entry and during follow-up. In a population with limited access to chronic disease care, and where many deliveries occur outside of a clinical setting, the period of PMTCT follow-up represents an opportunity to diagnose and initiate management of preexisting and pregnancy-related hypertension.