HIV risk behaviour, viraemia, and transmission across HIV cascade stages including low-level viremia: Analysis of 14 cross-sectional population-based HIV Impact Assessment surveys in sub-Saharan Africa

As antiretroviral treatment (ART) coverage for people living with HIV (PLHIV) increases, HIV programmes require up-to-date information about evolving HIV risk behaviour and transmission risk, including those with low-level viremia (LLV; >50 to ≤1000 copies/mL), to guide prevention priorities. We aimed to assess differences in sexual risk behaviours, distribution of viral load (VL) and proportion of transmission across PLHIV subgroups. We analysed data from Population-based HIV Impact Assessment surveys in 14 sub-Saharan African countries during 2015-2019. We estimated adjusted prevalence ratios (aPR) of self-reported HIV high-risk behaviour (multiple partners and condomless sex) across cascade stages via generalised estimation equations. We modelled the proportions of transmission from each subgroup using relative self-reported sexual risk, a Hill function for transmission rate by VL, and proportions within cascade stages from surveys and UNAIDS country estimates for 2010-2020. Compared to PLHIV with undetectable VL (≤50 copies/mL), undiagnosed PLHIV (aPR women: 1.28 [95% CI: 1.08-1.52]; men: 1.61 [1.33-1.95]) and men diagnosed but untreated (2.06 [1.52-2.78]) were more likely to self-report high-risk sex. High-risk behaviour was not significantly associated with LLV. Mean VL was similar among undiagnosed, diagnosed but untreated, and on ART but non-suppressed sub-groups. Across surveys, undiagnosed and diagnosed but untreated contributed most to transmission (40-91% and 1-41%, respectively), with less than 1% from those with LLV. Between 2010 and 2020, the proportion of transmission from individuals on ART but non-suppressed increased. In settings with high ART coverage, effective HIV testing, ART linkage, and retention remain priorities to reduce HIV transmission. Persons with LLV are an increasing share of PLHIV but their contribution to HIV transmission was small. Improving suppression among PLHIV on ART with VL ≥1000 copies/mL will become increasingly important.

Brief Report: Self-Reported HIV-Positive Status but Subsequent HIV-Negative Test Results in Population-Based HIV Impact Assessment Survey Participants-11 Sub-Saharan African Countries, 2015-2018

BACKGROUND

HIV testing is a critical step to accessing antiretroviral therapy (ART) because early diagnosis can facilitate earlier initiation of ART. This study presents aggregated data of individuals who self-reported being HIV-positive but subsequently tested HIV-negative during nationally representative Population-Based HIV Impact Assessment surveys conducted in 11 countries from 2015 to 2018.

METHOD

Survey participants aged 15 years or older were interviewed by trained personnel using a standard questionnaire to determine HIV testing history and self-reported HIV status. Home-based HIV testing and counseling using rapid diagnostic tests with return of results were performed by survey staff according to the respective national HIV testing services algorithms on venous blood samples. Laboratory-based confirmatory HIV testing for all participants identified as HIV-positives and self-reported positives, irrespective of HIV testing results, was conducted and included Geenius HIV-1/2 and DNA polymerase chain reaction if Geenius was negative or indeterminate.

RESULTS

Of the 16,630 participants who self-reported as HIV-positive, 16,432 (98.6%) were confirmed as HIV-positive and 198 (1.4%) were HIV-negative by subsequent laboratory-based testing. Participants who self-reported as HIV-positive but tested HIV-negative were significantly younger than 30 years, less likely to have received ART, and less likely to have received a CD4 test compared with participants who self-reported as HIV-positive with laboratory-confirmed infection.

CONCLUSIONS

A small proportion of self-reported HIV-positive individuals could not be confirmed as positive, which could be due to initial misdiagnosis, deliberate wrong self-report, or misunderstanding of the questionnaire. As universal ART access is expanding, it is increasingly important to ensure quality of HIV testing and confirmation of HIV diagnosis before ART initiation.

Trends in HIV prevalence, incidence, and progress towards the UNAIDS 95-95-95 targets in Malawi among individuals aged 15-64 years: population-based HIV impact assessments, 2015-16 and 2020-21

BACKGROUND

In 2014, UNAIDS set the goal of ending the AIDS epidemic by 2030 through the achievement of testing and treatment cascade targets. To evaluate progress achieved and highlight persisting gaps in HIV epidemic control in Malawi, we aimed to compare key indicators (prevalence, incidence, viral load suppression, and UNAIDS 95-95-95 targets) from the 2015-16 and 2020-21 Malawi Population-based HIV Impact Assessment (PHIA) survey results.

METHODS

The Malawi PHIAs were nationally representative, cross-sectional surveys with a two-stage cluster sampling design. The first survey was conducted between Nov 27, 2015, and Aug 26, 2016; the second survey was conducted between Jan 15, 2020, and April 26, 2021. Our analysis included survey participants aged 15-64 years. Participants were interviewed and a 14 mL blood sample was collected and tested for HIV infection using the national rapid testing algorithm. For each survey, we estimated key HIV epidemic indicators and achievement of 95-95-95 targets. The risk ratio (RR) of the indicators between surveys were computed and considered significant at a confidence level of 0·05. All results were weighted, and self-reported awareness and treatment status were adjusted to account for detection of antiretrovirals.

FINDINGS

Our analysis included 17 187 participants aged 15-64 years in 2015-16 and 21 208 in 2020-21 who participated in the surveys and blood draw. In the 2020-21 survey, 88·4% (95% CI 86·7-90·0) of people living with HIV were aware of their HIV-positive status; of those aware, 97·8% (97·1-98·5) were on antiretroviral therapy; and of those on treatment, 96·9% (95·9-97·7) were virally suppressed. Between surveys, the national HIV prevalence decreased significantly from 10·6% (10·0-11·2) to 8·9% (8·4-9·5) with RR 0·85 (95% CI 0·78-0·92; p<0·0001). The annual HIV incidence decreased from 0·37% (0·20-0·53) to 0·22% (0·11-0·34) with RR 0·61 (95% CI 0·31-1·20; p=0·15). The population viral load suppression increased from 68·3% (66·0-70·7) in 2015-16 to 87·0% (85·3-88·5) in 2020-21 (RR 1·27 [95% CI 1·22-1·32]; p<0·0001).

INTERPRETATION

These results suggest that Malawi had already surpassed the UNAIDS viral load suppression target for 2030 (85·7%) by 2020-21. Through strategies and evidence-informed interventions implemented in the last half decade, especially scale-up of effective HIV treatment, Malawi has made tremendous progress, including decreasing HIV prevalence and incidence and achieving both the second and third 95 targets ahead of 2030. To address the first 95, efforts in HIV diagnosis should focus on males and younger age groups. There is a continued need for effective linkage to care, retention on antiretroviral therapy, and adherence support to maintain and build on progress.

FUNDING

US President's Emergency Plan for AIDS Relief through the US Centers for Disease Control and Prevention.

The epidemiology of HIV population viral load in twelve sub-Saharan African countries

BACKGROUND

We examined the epidemiology and transmission potential of HIV population viral load (VL) in 12 sub-Saharan African countries.

METHODS

We analyzed data from Population-based HIV Impact Assessments (PHIAs), large national household-based surveys conducted between 2015 and 2019 in Cameroon, Cote d'Ivoire, Eswatini, Kenya, Lesotho, Malawi, Namibia, Rwanda, Tanzania, Uganda, Zambia, and Zimbabwe. Blood-based biomarkers included HIV serology, recency of HIV infection, and VL. We estimated the number of people living with HIV (PLHIV) with suppressed viral load (<1,000 HIV-1 RNA copies/mL) and with unsuppressed viral load (viremic), the prevalence of unsuppressed HIV (population viremia), sex-specific HIV transmission ratios (number female incident HIV-1 infections/number unsuppressed male PLHIV per 100 persons-years [PY] and vice versa) and examined correlations between a variety of VL metrics and incident HIV. Country sample sizes ranged from 10,016 (Eswatini) to 30,637 (Rwanda); estimates were weighted and restricted to participants 15 years and older.

RESULTS

The proportion of female PLHIV with viral suppression was higher than that among males in all countries, however, the number of unsuppressed females outnumbered that of unsuppressed males in all countries due to higher overall female HIV prevalence, with ratios ranging from 1.08 to 2.10 (median: 1.43). The spatial distribution of HIV seroprevalence, viremia prevalence, and number of unsuppressed adults often differed substantially within the same countries. The 1% and 5% of PLHIV with the highest VL on average accounted for 34% and 66%, respectively, of countries' total VL. HIV transmission ratios varied widely across countries and were higher for male-to-female (range: 2.3-28.3/100 PY) than for female-to-male transmission (range: 1.5-10.6/100 PY). In all countries mean log10 VL among unsuppressed males was higher than that among females. Correlations between VL measures and incident HIV varied, were weaker for VL metrics among females compared to males and were strongest for the number of unsuppressed PLHIV per 100 HIV-negative adults (R2 = 0.92).

CONCLUSIONS

Despite higher proportions of viral suppression, female unsuppressed PLHIV outnumbered males in all countries examined. Unsuppressed male PLHIV have consistently higher VL and a higher risk of transmitting HIV than females. Just 5% of PLHIV account for almost two-thirds of countries' total VL. Population-level VL metrics help monitor the epidemic and highlight key programmatic gaps in these African countries.

Toward elimination of mother-to-child transmission of HIV in Malawi: Findings from the Malawi Population-based HIV Impact Assessment (2015–2016)

Background

Malawi spearheaded the development and implementation of Option B+ for prevention of mother-to-child transmission of HIV (PMTCT), providing life-long ART for all HIV-positive pregnant and breastfeeding women. We used data from the 2015–2016 Malawi Population-based HIV Impact Assessment (MPHIA) to estimate progress toward 90-90-90 targets (90% of those with HIV know their HIV-positive status; of these, 90% are receiving ART; and of these, 90% have viral load suppression [VLS]) for HIV-positive women reporting a live birth in the previous 3 years.

Methods

MPHIA was a nationally representative household survey; consenting eligible women aged 15–64 years were interviewed on pregnancies and outcomes, including HIV status during their most recent pregnancy, PMTCT uptake, and early infant diagnosis (EID) testing. Descriptive analyses were weighted to account for the complex survey design. Viral load (VL) results were categorized by VLS (<1,000 copies/mL) and undetectable VL (target not detected/below the limit of detection).

Results

Of the 3,153 women included in our analysis, 371 (10.1%, 95% confidence interval [CI]: 8.8%–11.3%) tested HIV positive in the survey. Most HIV-positive women (84.2%, 95% CI: 79.9%–88.6%) reported knowing their HIV-positive status; of these, 94.9% (95% CI: 91.7%–98.2%) were receiving ART; and of these, 91.2% (95% CI: 87.4%–95.0%) had VLS. Among the 371 HIV-positive women, 76.0% (95% CI: 70.4%–81.7%) had VLS and 66.5% (95% CI: 59.8%–73.2%) had undetectable VL. Among 262 HIV-exposed children, 50.8% (95% CI: 42.8%–58.8%) received EID testing within 2 months of birth, whereas 17.9% (95% CI: 11.9%–23.8%) did not receive EID testing. Of 190 HIV-exposed children with a reported HIV test result, 2.1% (95% CI: 0.0%–4.6%) had positive results.

Conclusions

MPHIA data demonstrate high PMTCT uptake at a population level. However, our results identify some gaps in VLS in postpartum women and EID testing.

HIV incidence and prevalence among adults aged 15-64 years in Rwanda: Results from the Rwanda Population-based HIV Impact Assessment (RPHIA) and District-level Modeling, 2019

OBJECTIVES

The 2018-2019 Rwanda Population-based HIV Impact Assessment (RPHIA) was conducted to measure national HIV incidence and prevalence. District-level estimates were modeled to inform resources allocation.

METHODS

RPHIA was a nationally representative cross-sectional household survey. Consenting adults were interviewed and tested for HIV using the national diagnostic algorithm followed by laboratory-based confirmation of HIV status and testing for viral load (VL), limiting antigen (LAg) avidity, and presence of antiretrovirals. Incidence was calculated using normalized optical density ≤ 1·5, VL ≥ 1,000 copies/mL, and undetectable antiretrovirals. Survey and programmatic data were used to model district-level HIV incidence and prevalence.

RESULTS

Of 31,028 eligible adults, 98·7% participated in RPHIA and 934 tested HIV positive. HIV prevalence among adults in Rwanda was 3·0% (95% CI:2·7-3·3). National HIV incidence was 0·08% (95% CI:0·02-0·14) and 0·11% (95% CI:0·00-0·26) in the City of Kigali (CoK). Based on district-level modeling, HIV incidence was greatest in the 3 CoK districts (0·11% to 0·15%) and varied across other districts (0·03% to 0·10%).

CONCLUSIONS

HIV prevalence among adults in Rwanda is 3.0%; HIV incidence is low at 0.08%. District-level modeling has identified disproportionately affected urban hotspots: areas to focus resources.

Prevalence of and factors associated with late diagnosis of HIV in Malawi, Zambia, and Zimbabwe: Results from population-based nationally representative surveys

INTRODUCTION

Late diagnosis of HIV (LD) increases the risk of morbidity, mortality, and HIV transmission. We used nationally representative data from population-based HIV impact assessment (PHIA) surveys in Malawi, Zambia, and Zimbabwe (2015-2016) to characterize adults at risk of LD and to examine associations between LD and presumed HIV transmission to cohabiting sexual partners.

METHODS

We estimated the prevalence of LD, defined as CD4 count <350 cells/μL, among adults newly diagnosed with HIV during the surveys and odds ratios for associated factors. We linked newly diagnosed adults (index cases) to their household sexual partners and calculated adjusted odds ratios for associations between LD of the index case, viral load of the index case, and duration of HIV exposure in the relationship, and the HIV status of the household sexual partner.

RESULTS

Of 1,804 adults who were newly diagnosed with HIV in the surveys, 49% (882) were diagnosed late. LD was associated with male sex, older age, and almost five times the odds of having an HIV-positive household sexual partner (adjusted odds ratio [aOR], 4.65 [95% confidence interval: 2.56-8.45]). Longer duration of HIV exposure in a relationship and higher viral load of the index case were both independently associated with higher odds of having HIV-positive household sexual partners. Individuals with HIV exposure of more than 5 years had more than three times (aOR 3.42 [95% CI: 1.63-7.18]) higher odds of being HIV positive than those with less than 2 years HIV exposure. The odds of being HIV positive were increased in individuals who were in a relationship with an index case with a viral load of 400-3499 copies/mL (aOR 4.06 [95% CI 0.45-36.46]), 3,500-9,999 copies/mL (aOR 11.32 [95% CI: 4.08-31.39]), 10,000-49,999 copies/mL (aOR 17.07 [95% CI: 9.18-31.72]), and ≥50,000 copies/mL (aOR 28.41 [95% CI: 12.18-66.28]) compared to individuals who were in a relationship with an index case with a viral load of <400 copies/mL.

CONCLUSIONS

LD remains a challenge in Southern Africa and is strongly associated with presumed HIV transmission to household sexual partners. Our study underscores the need for earlier HIV diagnosis, particularly among men and older adults, and the importance of index testing.

Opportunities for Closing the Gap in HIV Diagnosis, Treatment, and Viral Load Suppression in Children in Malawi: Results From a 2015-2016 Population-based HIV Impact Assessment Survey

BACKGROUND

Control of the pediatric HIV epidemic is hampered by gaps in diagnosis and linkage to effective treatment. The 2015-2016 Malawi Population-based HIV impact assessment data were analyzed to identify gaps in pediatric HIV diagnosis, treatment, and viral load suppression.

METHODS

In half of the surveyed households, children ages ≥18 months to <15 years were tested using the national HIV rapid test algorithm. Children ≤18 months reactive by the initial rapid test underwent HIV total nucleic acid polymerase chain reaction confirmatory testing. Blood from HIV-positive children was tested for viral load (VL) and presence of antiretroviral drugs. HIV diagnosis and antiretroviral treatment (ART) use were defined using guardian-reporting or antiretroviral detection.

RESULTS

Of the 6166 children tested, 99 were HIV-positive for a prevalence of 1.5% (95% confidence intervals [CI]: 1.1-1.9) and 8.0% (95% CI: 5.6-10.5) among HIV-exposed children. The prevalence of 1.5% was extrapolated to a national estimate of 119,501 (95% CI: 89,028-149,974) children living with HIV (CLHIV), of whom, 30.7% (95% CI: 20.3-41.1) were previously undiagnosed. Of the 69.3% diagnosed CLHIV, 86.1% (95% CI: 76.8-95.6) were on ART and 57.9% (95% CI: 41.4-74.4) of those on ART had suppressed VL (<1000 HIV RNA copies/mL). Among all CLHIV, irrespective of HIV diagnosis or ART use, 57.7% (95% CI: 45.0-70.5) had unsuppressed VL.

CONCLUSIONS

Critical gaps in HIV diagnosis in children persist in Malawi. The large proportion of CLHIV with unsuppressed VL reflects gaps in diagnosis and need for more effective first- and second-line ART regimens and adherence interventions.

Disease progression and mortality with untreated HIV infection: evidence synthesis of HIV seroconverter cohorts, antiretroviral treatment clinical cohorts and population-based survey data

Introduction

Model‐based estimates of key HIV indicators depend on past epidemic trends that are derived based on assumptions about HIV disease progression and mortality in the absence of antiretroviral treatment (ART). Population‐based HIV Impact Assessment (PHIA) household surveys conducted between 2015 and 2018 found substantial numbers of respondents living with untreated HIV infection. CD4 cell counts measured in these individuals provide novel information to estimate HIV disease progression and mortality rates off ART.

Methods

We used Bayesian multi‐parameter evidence synthesis to combine data on (1) cross‐sectional CD4 cell counts among untreated adults living with HIV from 10 PHIA surveys, (2) survival after HIV seroconversion in East African seroconverter cohorts, (3) post‐seroconversion CD4 counts and (4) mortality rates by CD4 count predominantly from European, North American and Australian seroconverter cohorts. We used incremental mixture importance sampling to estimate HIV natural history and ART uptake parameters used in the Spectrum software. We validated modelled trends in CD4 count at ART initiation against ART initiator cohorts in sub‐Saharan Africa.

Results

Median untreated HIV survival decreased with increasing age at seroconversion, from 12.5 years [95% credible interval (CrI): 12.1–12.7] at ages 15–24 to 7.2 years (95% CrI: 7.1–7.7) at ages 45–54. Older age was associated with lower initial CD4 counts, faster CD4 count decline and higher HIV‐related mortality rates. Our estimates suggested a weaker association between ART uptake and HIV‐related mortality rates than previously assumed in Spectrum. Modelled CD4 counts in untreated people living with HIV matched recent household survey data well, though some intercountry variation in frequencies of CD4 counts above 500 cells/mm³ was not explained. Trends in CD4 counts at ART initiation were comparable to data from ART initiator cohorts. An alternate model that stratified progression and mortality rates by sex did not improve model fit appreciably.

Conclusions

Synthesis of multiple data sources results in similar overall survival as previous Spectrum parameter assumptions but implies more rapid progression and longer survival in lower CD4 categories. New natural history parameter values improve consistency of model estimates with recent cross‐sectional CD4 data and trends in CD4 counts at ART initiation.

Population Viral Load, Viremia, and Recent HIV-1 Infections: Findings From Population-Based HIV Impact Assessments (PHIAs) in Zimbabwe, Malawi, and Zambia

BACKGROUND

HIV population viral load (PVL) can reflect antiretroviral therapy program effectiveness and transmission potential in a community. Using nationally representative data from household surveys conducted in Zimbabwe, Malawi, and Zambia in 2015-16, we examined the association between various VL measures and the probability of at least one recent HIV-1 infection in the community.

METHODS

We used limiting-antigen avidity enzyme immunoassay, viral load suppression (VLS) (HIV RNA <1000 copies/mL), and antiretrovirals in the blood to identify recent HIV-1 cases.

RESULTS

Among 1510 enumeration areas (EAs) across the 3 surveys, 52,036 adults aged 15-59 years resided in 1363 (90.3%) EAs with at least one HIV-positive adult consenting to interview and blood draw and whose VL was tested. Mean HIV prevalence across these EAs was 13.1% [95% confidence intervals (CI) 12.7 to 13.5]. Mean VLS prevalence across these EAs was 58.7% (95% CI: 57.3 to 60.0). In multivariable analysis, PVL was associated with a recent HIV-1 case in that EA (adjusted odds ratio: 1.4, 95% CI: 1.2 to 1.6, P = 0.001). VLS prevalence was inversely correlated with recent infections (adjusted odds ratio: 0.3, 95% CI: 0.1 to 0.6, P = 0.004). The 90-90-90 indicators, namely, the prevalence of HIV diagnosis, antiretroviral therapy coverage, and VLS at the EA level, were inversely correlated with HIV recency at the EA level.

CONCLUSIONS

We found a strong association between PVL and VLS prevalence and recent HIV-1 infection at the EA level across 3 southern African countries with generalized HIV epidemics. These results suggest that population-based measures of VLS in communities may serve as a proxy for epidemic control.

Population-Based HIV Impact Assessments Survey Methods, Response, and Quality in Zimbabwe, Malawi, and Zambia

BACKGROUND

The population-based HIV impact assessment (population-based HIV impact assessments) surveys are among the first to estimate national adult HIV incidence, subnational prevalence of viral load suppression, and pediatric HIV prevalence. We summarize the survey methods implemented in Zimbabwe, Malawi, and Zambia, as well as response rates and quality metrics.

METHODS

Each cross-sectional, household-based survey used a 2-stage cluster design. Survey preparations included sample design, questionnaire development, tablet programming for informed consent and data collection, community mobilization, establishing a network of satellite laboratories, and fieldworker training. Interviewers collected demographic, behavioral, and clinical information using tablets. Blood was collected for home-based HIV testing and counseling (HBTC) and point-of-care CD4+ T-cell enumeration with results immediately returned. HIV-positive blood samples underwent laboratory-based confirmatory testing, HIV incidence testing, RNA polymerase chain reaction (viral load), DNA polymerase chain reaction (early infant diagnosis), and serum antiretroviral drug detection. Data were weighted for survey design, and chi square automatic interaction detection-based methods were used to adjust for nonresponse.

RESULTS

Each survey recruited a nationally representative, household-based sample of children and adults over a 6-10-month period in 2015 and 2016. Most (84%-90%) of the 12,000-14,000 eligible households in each country participated in the survey, with 77%-81% of eligible adults completing an interview and providing blood for HIV testing. Among eligible children, 59%-73% completed HIV testing. Across the 3 surveys, 97.8% of interview data were complete and had no errors.

CONCLUSION

Conducting a national population-based HIV impact assessment with immediate return of HIV and other point-of-care test results was feasible, and data quality was high.

Screening for HIV Among Patients at Tuberculosis Clinics - Results from Population-Based HIV Impact Assessment Surveys, Malawi, Zambia, and Zimbabwe, 2015-2016

The World Health Organization and national guidelines recommend HIV testing and counseling at tuberculosis (TB) clinics for all patients, regardless of TB diagnosis (1). Population-based HIV Impact Assessment (PHIA) survey data for 2015-2016 in Malawi, Zambia, and Zimbabwe were analyzed to assess HIV screening at TB clinics among persons who had positive HIV test results in the survey. The analysis was stratified by history of TB diagnosis* (presumptive versus confirmed^†), awareness^§ of HIV-positive status, antiretroviral therapy (ART)^¶ status, and viral load suppression among HIV-positive adults, by history of TB clinic visit. The percentage of adults who reported having ever visited a TB clinic ranged from 4.7% to 9.7%. Among all TB clinic attendees, the percentage who reported that they had received HIV testing during a TB clinic visit ranged from 48.0% to 62.1% across the three countries. Among adults who received a positive HIV test result during PHIA and who did not receive a test for HIV at a previous TB clinic visit, 29.4% (Malawi), 21.9% (Zambia), and 16.2% (Zimbabwe) reported that they did not know their HIV status at the time of the TB clinic visit. These findings represent missed opportunities for HIV screening and linkage to HIV care. In all three countries, viral load suppression rates were significantly higher among those who reported ever visiting a TB clinic than among those who had not (p<0.001). National programs could strengthen HIV screening at TB clinics and leverage them as entry points into the HIV diagnosis and treatment cascade (i.e., testing, initiation of treatment, and viral load suppression).

Prevalence of nonsuppressed viral load and associated factors among HIV-positive adults receiving antiretroviral therapy in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe (2015 to 2017): results from population-based nationally representative surveys

INTRODUCTION

The global target for 2020 is that ≥90% of people living with HIV (PLHIV) receiving antiretroviral therapy (ART) will achieve viral load suppression (VLS). We examined VLS and its determinants among adults receiving ART for at least four months.

METHODS

We analysed data from the population-based HIV impact assessment (PHIA) surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe (2015 to 2017). PHIA surveys are nationally representative, cross-sectional household surveys. Data collection included structured interviews, home-based HIV testing and laboratory testing. Blood samples from PLHIV were analysed for HIV RNA, CD4 counts and recent exposure to antiretroviral drugs (ARVs). We calculated representative estimates for the prevalence of VLS (viral load <1000 copies/mL), nonsuppressed viral load (NVL; viral load ≥1000 copies/mL), virologic failure (VF; ARVs present and viral load ≥1000 copies/mL), interrupted ART (ARVs absent and viral load ≥1000 copies/mL) and rates of switching to second-line ART (protease inhibitors present) among PLHIV aged 15 to 59 years who participated in the PHIA surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe, initiated ART at least four months before the survey and were receiving ART at the time of the survey (according to self-report or ARV testing). We calculated odds ratios and incidence rate ratios for factors associated with NVL, VF, interrupted ART, and switching to second-line ART.

RESULTS

We included 9200 adults receiving ART of whom 88.8% had VLS and 11.2% had NVL including 8.2% who experienced VF and 3.0% who interrupted ART. Younger age, male sex, less education, suboptimal adherence, receiving nevirapine, HIV non-disclosure, never having married and residing in Zimbabwe, Lesotho or Zambia were associated with higher odds of NVL. Among people with NVL, marriage, female sex, shorter ART duration, higher CD4 count and alcohol use were associated with lower odds for VF and higher odds for interrupted ART. Many people with VF (44.8%) had CD4 counts <200 cells/µL, but few (0.31% per year) switched to second-line ART.

CONCLUSIONS

Countries are approaching global VLS targets for adults. Treatment support, in particular for younger adults, and people with higher CD4 counts, and switching of people to protease inhibitor- or integrase inhibitor-based regimens may further reduce NVL prevalence.

Low Protein Intake Irrespective of Source is Associated with Higher Mortality Among Older Community-dwelling Men

OBJECTIVES

Our aim was to determine the association between protein intake (overall and by source) and all-cause and cause-specific mortality among older men.

DESIGN

Prospective cohort study.

SETTING

5790 ambulatory community-dwelling older men from multicenter Osteoporotic Fractures in Men (MrOS) study.

MEASUREMENTS

Total energy and protein intake, and protein intake by source (dairy, non-dairy animal, plant) were assessed using a 69-item food frequency questionnaire. We included up to 10-year follow-up with adjudicated cardiovascular, cancer and other mortality outcomes. We used time-to-event analysis with protein exposures, mortality outcome, and adjusted for possible confounders including age, center, education, race, smoking, alcohol use, physical activity, weight, total energy intake (TEI), and comorbidities. Hazard ratios were expressed per each unit=2.9% TEI decrement for all protein intake variables.

RESULTS

The mean (SD) baseline age of 5790 men was 73.6 (5.8) y. There were 1611 deaths and 211 drop-outs prior to 10 years, and 3868 men who were alive at the 10-year follow-up. The mean (SD) total protein intake was 64.7 (25.8) g/d, while the mean (SD) intake expressed as percent of total energy intake (%TEI) was 16.1 (2.9) %TEI. Lower protein intake was associated with an increased risk of death, with unadjusted HR=1.11 (95% CI: 1.06, 1.17) and adjusted HR=1.09 (95% CI: 1.04, 1.14) and the associations for protein intake by source were similar. The adjusted HR for cancer mortality was HR=1.13 (95% CI: 1.03, 1.25) while the association for CVD mortality was HR=1.08 (95% CI: 0.99, 1.18).

CONCLUSIONS

Low protein intake, irrespective of source, was associated with a modest increase in risk of all-cause and cause-specific mortality among older men. Special consideration should be given to level of protein intake among older adults.

Association of Diabetes and Tuberculosis Disease among US-Bound Adult Refugees, 2009-2014

Diabetes is associated with an increased risk for active tuberculosis (TB) disease. We conducted a case-control study and found a significant association between diabetes and TB disease among US-bound refugees. These findings underscore the value of collaborative management of both diseases.

Incidence and correlates of tuberculosis IGRA conversion among HIV-infected postpartum women

SETTING

Prevention of maternal-to-child transmission program at a tertiary care hospital in Nairobi, Kenya. The risk of acquiring Mycobacterium tuberculosis infection among peripartum human immunodeficiency virus (HIV) infected women is poorly defined.

OBJECTIVE

To determine the incidence of and co-factors for interferon-gamma release assay (IGRA) conversion among postpartum HIV-infected women using T-SPOT.TB.

DESIGN

We used data and cryopreserved peripheral blood mononuclear cells from a historical cohort of HIV-infected women enrolled at 32 weeks' gestation and followed for 1 year postpartum between 1999 and 2005.

RESULTS

Of 89 women initially IGRA-negative during pregnancy, 11 (12.4%) became positive, 53 (59.5%) remained negative and 25 (28.1%) were indeterminate at 1 year postpartum. Mean interferon-gamma (IFN-γ) response among converters increased from ~1 to >50 spot-forming cells/well (P = 0.015). IGRA conversion was significantly associated with partner HIV infection, flush toilets, maternal illness and cough during follow-up, but not maternal CD4 count or HIV viral load.

CONCLUSION

The high rates of IGRA conversion seen among HIV-infected postpartum women in our study are similar to those of other groups at high risk for M. tuberculosis infection. This has important implications for M. tuberculosis infection screening strategies and provision of preventive therapy for the health of women and their infants.

Prognostic Performance of Current Stage III Oral Cancer Patients After Curative Intent Resection: Evidence to Support a Revision of the American Joint Committee on Cancer Staging System

BACKGROUND

The American Joint Committee on Cancer (AJCC) stage III classification of oral cavity squamous cell carcinoma (OCSCC) represents a heterogeneous group of patients with early local disease with regional metastases (T1N1 and T2N1) and advanced local disease with or without regional metastasis (T3N0 and T3N1).

OBJECTIVE

The aim of this study was to evaluate prognostic heterogeneity in the stage III category.

METHODS AND PATIENTS

An international retrospective multicenter study of 1815 patients who were treated for OCSCC from 2003 to 2011.

RESULTS

Kaplan-Meier survival analysis and multivariate models of stage III patients revealed better overall survival (OS; HR 2.12, 95 % CI 1.03-4.15; p = 0.01) and disease-specific survival (DSS; HR 1.7, 95 % CI 1.16-4.12; p = 0.04) rates for patients with T1-2N1/T3N0 disease than for patients with T3N1 disease. The outcomes of patients with T3N1 and stage IVa disease were similar (p = 0.89 and p = 0.78 for OS and DSS, respectively). Modifying stage classification by transferring the T3N1 category to the stage VIa group resulted in a better prognostic performance [Harrell's concordance index, C index 0.76; Akaike's Information Criterion (AIC) 4131.6] compared with the AJCC 7th edition staging system (C index 0.65; AIC 4144.9) for OS. When DSS was assessed, the suggested staging system remained the best performing model (C index 0.71; AIC 1061.3) compared with the current AJCC 7th edition staging (C index 0.64; AIC 1066.2).

CONCLUSIONS

The prognosis of T3N1 and stage IVa disease are similar in OCSCC, suggesting that these categories could be combined in future revisions of the nodal staging system to enhance prognostic accuracy.

Latent tuberculosis detection by interferon γ release assay during pregnancy predicts active tuberculosis and mortality in human immunodeficiency virus type 1-infected women and their children

BACKGROUND

We evaluated the prognostic usefulness of interferon γ release assays (IGRAs) for active tuberculosis and mortality in Kenyan human immunodeficiency virus type 1 (HIV-1)-infected women and their infants.

METHODS

Prevalence and correlates of Mycobacterium tuberculosis-specific T-SPOT.TB IGRA positivity were determined during pregnancy in a historical cohort of HIV-1-infected women. Hazard ratios, adjusted for baseline maternal CD4 cell count (aHR(CD4)), were calculated for associations between IGRA positivity and risk of active tuberculosis and mortality over 2-year postpartum follow-up among women and their infants.

RESULTS

Of 333 women tested, 52 (15.6%) had indeterminate IGRA results. Of the remaining 281 women, 120 (42.7%) had positive IGRA results, which were associated with a 4.5-fold increased risk of active tuberculosis (aHR(CD4), 4.5; 95% confidence interval [CI], 1.1-18.0; P = .030). For immunosuppressed women (CD4 cell count, <250 cells/μL), positive IGRA results were associated with increased risk of maternal mortality (aHR(CD4), 3.5; 95% CI, 1.02-12.1;), maternal active tuberculosis or mortality (aHR(CD4), 5.2; 95% CI, 1.7-15.6; P = .004), and infant active tuberculosis or mortality overall (aHR(CD4), 3.0; 95% CI, 1.0-8.9; P = .05) and among HIV-1-exposed uninfected infants (aHR(CD4), 7.3; 95% CI, 1.6-33.5; P = .01).

CONCLUSIONS

Positive IGRA results for HIV-1-infected pregnant women were associated with postpartum active tuberculosis and mortality among mothers and their infants.

The effect of coencapsulation of bovine insulin with cyclodextrins in ethylcellulose microcapsules

Polymeric microcapsules have been widely investigated for protein delivery. Common problems include: low stability, low encapsulation efficiency, lack of uniformity, and burst release. Cyclodextrins (CDs) are known to enhance stability and solubility of proteins in solution. This research examines the effect of alpha-, beta-, and gamma-CDs on: (1) stability, (2) encapsulation, and (3) release of insulin from ethylcellulose microcapsules. All CDs improved thermal stability of insulin by lowering the enthalpy of unfolding by 16-52%. alpha- and gamma-CDs also increased the encapsulation efficiency of insulin and improved uniformity of the microcapsule formulations. Two mathematical models were proposed to account for insulin release and consisted of multiple zero order and first order input processes, and a single first order output process. All CDs decreased the initial burst release of insulin by up to 30%. This research demonstrates the potential for CDs to improve stability, uniformity, and encapsulation of proteins in microcapsule formulations.

Comparison of white light and narrow band high definition images in predicting colon polyp histology, using standard colonoscopes without optical magnification

BACKGROUND AND STUDY AIMS

Narrow band imaging (NBI) with optical magnification is useful in predicting colon polyp histology. As magnifying endoscopes are not routinely available, we investigated the use of NBI and high definition white light imaging in determining polyp histology, using images obtained with colonoscopes without optical magnification.

PATIENTS AND METHODS

Images (white light and NBI) of colon polyps less than 10 mm in diameter were collected prospectively from patients undergoing screening colonoscopy and digitally stored. Two endoscopists later reviewed all images and predicted polyp histology as neoplastic or non-neoplastic using a modified Kudo classification. Comparison was made with histopathology.

RESULTS

Separate white light and NBI images of 80 polyps (49 neoplastic, 31 non-neoplastic) from 63 patients were recorded. Mean polyp size was 5.1 +/- 2.1 mm (5.4 +/- 2.2 neoplastic; 4.4 +/- 1.8 non-neoplastic; P = 0.02). In a pooled analysis, NBI correctly predicted neoplastic histology in 93 of 98 images (sensitivity 95 %, positive predictive value [PPV] 94 %) whereas white light did so in 58 of 98 images (sensitivity 59 %, PPV 79 %). NBI correctly predicted non-neoplastic histology in 56 of 62 images (specificity 90 %, negative predictive value [NPV] 92 %) whereas white light did so in 47 of 62 images (specificity 76 %, NPV 54 %).

CONCLUSIONS

NBI without optical magnification was more accurate in predicting colon polyp histology compared with white light imaging. Image quality and confidence in histology were significantly higher in the NBI group. NBI without optical magnification may be useful in predicting colon polyp histology.

The impact of endoscopic ultrasonography with fine needle aspiration (EUS-FNA) on esophageal cancer staging: a survey of thoracic surgeons and gastroenterologists

Accurate staging of esophageal cancer is critical to achieving optimal treatment outcomes. End-oscopic ultrasound with fine needle aspiration (EUS-FNA) has emerged as a valuable tool for locoregional staging. However, it is unclear how different physician specialties perceive the benefit of EUS-FNA for esophageal cancer staging, and thus utilize this modality in clinical practice. A survey regarding utilization of EUS-FNA in esophageal cancer was distributed to 211 thoracic surgeons and 251 EUS-capable gastroenterologists. Seventy-six thoracic surgeons (36%) and 78 gastroenterologists (31%) responded to the survey. Most surgeons (75%) use EUS to stage potentially resectable esophageal cancer 75% of the time. Surgeons using EUS less often are less likely to have access to high-quality EUS services than their peers. Fewer surgeons believe EUS is the most accurate test for T and N-staging (84% and 71%, respectively) as compared with gastroenterologists (97% and 96%, P < 0.01 for both). Most endosonographers (68%) decide whether to dilate a malignant esophageal stricture to complete the staging exam on a case-by-case basis. Surgeons disagree as to whether involvement of celiac lymph nodes should preclude esophagectomy in distal esophageal cancer. While most thoracic surgeons have embraced EUS-FNA as the most accurate locoregional staging modality in esophageal cancer, this attitude is not fully reflected in utilization patterns due to a lack of quality EUS services in some centers. Controversial areas that warrant further study include dilation of malignant strictures to facilitate EUS staging, and the implication of involved celiac lymph nodes on management.

Infant feeding practices of HIV-positive mothers in India

Exclusive breast-feeding is widely accepted and advocated in India; however, clinicians are now faced with advising women infected with human immunodeficiency virus (HIV) about the risks and benefits of other infant feeding options. This study assessed factors that influence the infant feeding decisions of HIV-infected mothers in Pune, India. From December 2000 to April 2002, HIV-positive (HIV(+)) pregnant women (n = 101) from a government hospital antenatal clinic were interviewed prepartum about infant feeding intention, feeding practice immediately postpartum and feeding after a minimum of 2 wk postpartum. Of the HIV(+) sample, the last 39 were interviewed more intensively to examine factors affecting feeding decision making. We found that an equal number of HIV(+) women intended to breast-feed (44%) or give top milk (44%) (diluted animal milk). Women who chose to top feed were also more likely to disclose their HIV status to family members. Mixed feeding occurred frequently in our sample (29%); however, for the majority of those (74%), it lasted only 3 d postpartum. The hospital counselor had an important role in assisting women in their intended feeding choice as well as actual practice. The time immediately after delivery was noted as critical for recounseling about infant feeding and further support of the woman's decision, thus lowering the risk of mixed feeding. Lack of funds, poor hygienic conditions and risk of social repercussions were more commonly noted as reasons to breast-feed. Top milk, the alternative for breast-milk used in this population, however, must be investigated further to assess its nutritional value and safety before it can be endorsed widely for infants of HIV(+) women.

Ornithine transcarbamylase deficiency unmasked because of gastrointestinal bleeding

Ornithine transcarbamylase (OTC) is a mitochondrial-matrix enzyme that catalyzes conversion of ornithine and carbamyl phosphate to citrulline, the second step in the urea cycle. The urea cycle is the most important pathway to detoxification of ammonia in human beings. Ornithine transcarbamylase deficiency (OTCD) is the most common urea cycle disorder, inherited as an X-linked disorder that can cause fatal hyperammonemia in male newborns. Women with OTCD have a variable expression of their disease, the variability being determined by lyonization (random inactivation) of the X chromosome. We report a case of a 28-year-old woman who presented with hyperammonemic encephalopathy that was precipitated by a gastrointestinal bleed unmasking OTCD.

Gallstones, from gallbladder to gut. Management options for diverse complications

Gallstones may be incidental and asymptomatic or painful and accompanied by life-threatening obstruction or infection. A thorough knowledge of potential complications is therefore critical, especially because some asymptomatic stones require prompt treatment. In this article, Drs Agrawal and Jonnalagadda provide valuable instructions for recognizing and treating the various manifestations of gallstone disease.

Lowering dietary saturated fat and total fat reduces the oxidative susceptibility of LDL in healthy men and women

The present study examined the effects of reducing dietary total fat and saturated fat (SFA) on LDL oxidative susceptibility in 27 healthy men and women (age 24-65 y). Each subject consumed each of three diets for 8 wk: an average American diet (AAD, 34% energy from fat, 15% from SFA), a Step-1 diet (29% fat, 9% SFA) and a very low SFA diet (Low-Sat, 25% fat, 6% SFA). In vitro LDL oxidation was assessed by copper-mediated oxidation, as measured by the kinetics of conjugated diene formation and lipid peroxide formation. Compared with the AAD, plasma LDL-cholesterol (LDL-C) and HDL cholesterol levels were 8% lower (P: = 0.16 and P: = 0.11, respectively), in subjects when they consumed the Step-1 diet and 11% (P: < 0.03) and 14% (P: < 0.057) lower, respectively, when they consumed the Low-Sat diet. Conjugated diene production and oxidation rate were 7% (P: < 0. 05) and 9% (P: < 0.05) lower, respectively. The reduction of lipid peroxide formation was 9% (P: < 0.05) in subjects when they consumed the Low-Sat diet vs. the AAD. In addition, lipid peroxide and conjugated diene formation were positively correlated with plasma total and LDL-C and apolipoprotein B (apo B) levels (r = 0.5-0.6, P: < 0.001), suggesting that quantity of LDL is an important determinant of oxidative modification. Furthermore, at the same level of apo B or LDL-C, LDL from subjects when they consumed either Step-1 or Low-Sat diets was less susceptible (P: < 0.05) to oxidation than those when they consumed the AAD, suggesting that qualitative changes also affect LDL oxidative susceptibility. Therefore, the benefits of lowering dietary SFA may extend beyond decreasing LDL-C levels and include favorable qualitative changes in LDL that further decrease risk of coronary heart disease.

Purification and characterization of flavokinase from Neurospora crassa

The ATP-dependent phosphorylation of riboflavin to FMN by flavokinase is the key step in flavin biosynthesis. Flavokinase has been purified from a fungal source for the first time. The enzyme purified from a cell wall lacking mutant of Neurospora crassa, slime, is a monomer of M(r) 35.5 kDa with maximal activity at alkaline pH and high temperature (55 degrees C). The K(m) for both substrates is the lowest reported for flavokinase from any source so far (120 nM for riboflavin and 210 nM for MgATP2-). The enzyme exhibits preference for Mg2+ over Zn2+ as the essential activator and is also significantly activated by several cations. Activation by orthophosphate may be physiologically relevant for the intracellular regulation of flavokinase.

Effects of the National Cholesterol Education Program's Step I and Step II dietary intervention programs on cardiovascular disease risk factors: a meta-analysis

BACKGROUND

Plasma lipid and lipoprotein responses have been variable in dietary intervention studies.

OBJECTIVE

The objective of this study was to evaluate the effects of the National Cholesterol Education Program's Step I and Step II dietary interventions on major cardiovascular disease risk factors using meta-analysis.

DESIGN

MEDLINE was used to select 37 dietary intervention studies in free-living subjects published from 1981 to 1997.

RESULTS

Step I and Step II dietary interventions significantly decreased plasma lipids and lipoproteins. Plasma total cholesterol (TC), LDL cholesterol, triacylglycerol, and TC:HDL cholesterol decreased by 0.63 mmol/L (10%), 0.49 mmol/L (12%), 0.17 mmol/L (8%), and 0.50 (10%), respectively, in Step I intervention studies, and by 0.81 mmol/L (13%), 0.65 mmol/L (16%), 0.19 mmol/L (8%), and 0.34 (7%), respectively, in Step II intervention studies (P < 0.01 for all). HDL cholesterol decreased by 7% (P = 0.05) in response to Step II but not to Step I dietary interventions. Positive correlations between changes in dietary total and saturated fatty acids and changes in TC and LDL and HDL cholesterol were observed (r = 0.59, 0.61, and 0.46, respectively; P < 0.001). Multiple regression analyses showed that for every 1% decrease in energy consumed as dietary saturated fatty acid, TC decreased by 0.056 mmol/L and LDL cholesterol by 0.05 mmol/L. Moreover, for every 1-kg decrease in body weight, triacylglycerol decreased by 0.011 mmol/L and HDL cholesterol increased by 0.011 mmol/L. Exercise resulted in greater decreases in TC, LDL cholesterol, and triacylglycerol and prevented the decrease in HDL cholesterol associated with low-fat diets.

CONCLUSION

Step I and Step II dietary interventions have multiple beneficial effects on important cardiovascular disease risk factors.

Orthophosphate is a non-essential activator of Vigna radiata flavokinase

The ATP-dependent phosphorylation of riboflavin to FMN by flavokinase from Vigna radiata was activated by orthophosphate (Pi) in a concentration dependent manner. Pi affected both the K(m) and Vmax, indicating that it is a non-essential, mixed type activator. The extent of activation by Pi was dependent on the cation (Mg2+ or Zn2+). Activation by other anions could be correlated to similarity to Pi in molecular size and structure. These observations suggest the presence of a binding site(s) for a phosphate-like anion on flavokinase.

Activation of enzymatic catalysis

Modulation of enzyme activity by inhibition and activation plays an important physiological role in regulation of cellular metabolism. Compared to the wealth of information available regarding inhibition of metabolic pathways, little is known about activation. Limited proteolysis of zymogens exemplifies irreversible activation. Reversible activation may involve post-translational modifications or dissociable binding of small molecules. Sometimes, chemical modification may also activate enzymes. The influence of small molecules on the reversible binding and activation of enzymes is summarized.

Combinatorial synthesis and screening of a chemical library of 1,4-dihydropyridine calcium channel blockers

Solid-phase synthesis of a 300-member pharmacophore library of 1,4-dihydropyridines from keto ester, diketone and aldehyde building blocks on a cleavable amine polymeric support is described. Screening and serial deconvolution of the combinatorial library has resulted in identification of known and new potent calcium channel blockers.

Perils of partitioning: A case study of flavins and flavokinase

Partitioning is a common procedure for the separation of two solutes from a solution based on their differential solubility in an immiscible solvent. This has been widely used to quantitate riboflavin, flavin mononucleotide (FMN), and flavin adenine dinucleotide in aqueous samples by extraction with water-saturated benzyl alcohol. Here we report that the partitioning of riboflavin and FMN is affected by the presence of each other in a concentration-dependent manner, thus rendering this procedure unsuitable for quantitation. Direct quantitation of FMN formed in assays for flavokinase from Vigna radiata shows that kinetic analyses using a partition-based assay lead to erroneous conclusions.

Candida albicans osteomyelitis in a liver transplant recipient: a case report and review of the literature

A 51-year-old man developed fever and back pain 2 months after orthotopic liver transplantation for end-stage liver disease secondary to chronic hepatitis C infection. CT scan demonstrated destructive lesions in T12 suggestive of osteomyelitis. Aspiration biopsy of the vertebra revealed granulomatous inflammation and yeast forms; culture yielded Candida albicans. The patient improved with intravenous amphotericin B and 5-fluorocytosine and did not require surgical intervention. Candida osteomyelitis is a rare condition and to our knowledge it has not been reported before in liver transplant recipients. Awareness of this potential complication may shorten the delay in making the definitive diagnosis, which in turn may increase the likelihood of a response without sequela.

Modulation of cholecystokinin activity by albumin

We found that a variety of cholecystokinin (CCK) receptor ligands bind to bovine serum albumin (BSA). This binding was rapid, fully reversible, temperature independent, of low affinity, and specific for BSA; it depended on the concentration of BSA, the chemical structure of the ligand, and the chemical composition of the incubation medium. BSA also decreased the binding of 125I-labeled CCK octapeptide (125I-CCK-8) to CCK receptors on pancreatic acini and membranes but increased the potency with which CCK-8 inhibited binding of 125I-CCK-8. These counterintuitive findings appeared to result from BSA altering the affinities of CCK-8 for different affinity states of the pancreatic CCK receptor. An alternate hypothesis is that BSA increased the efficacy of CCK-8 such that it bound to receptors and also caused biochemical changes in other receptors that reduced their ability to bind 125I-CCK-8. BSA enhanced the ability of CCK-8 to stimulate amylase secretion from pancreatic acini and to cause contraction of dispersed gastric smooth muscle cells. Thus, CCK can bind to BSA, and the BSA-CCK complex has substantially different activities from the free, uncomplexed hormone.