Evaluation of the accuracy of the Asanté assay as a point-of-care rapid test for HIV-1 recent infections using serum bank specimens from blood donors in South Africa, July 2018 - August 2021

BACKGROUND

Point-of-care (POC) rapid recency testing can be used as a cost-effective tool to identify recently infected individuals (i.e. infected within the last 12 months) in near-real time, support epidemic control and identify hotspots for transmission as part of recent infection surveillance.

OBJECTIVE

To evaluate the performance of the Asanté (HIV-1) rapid recency assay as a POC rapid test among blood donors in South Africa (SA).

METHODS

The study was a cross-sectional and validity study of the Asanté HIV-1 Rapid Recency Assay performed on 715 consecutively archived plasma donor specimens from the SA National Blood Services to determine their recency and established HIV infection status. ELISA and rapid assays for HIV antibody detection were used as the reference-testing standard for confirming an infection, while the Maxim HIV-1 limiting antigen (LAg) avidity assay was used as a reference for comparing HIV recency status. Validity tests (sensitivity, specificity, negative and positive predictive values) and Cohen-Kappa tests of the agreement were conducted to compare the Asanté HIV-1 rapid recency assay results with the reference tests.

RESULTS

Of the 715 studied blood samples, 63.1% (n=451/715) were confirmed to be HIV-positive based on the reference standard. The sensitivity and specificity of the Asanté HIV-1 rapid recency assay in diagnosing established HIV infection compared to the ELISA were 98.4% (95% CI 96.7 - 99.3) and 99.6% (95% CI 97.6 - 100), respectively. Compared with HIV rapid assay, the sensitivity and specificity of the Asanté HIV-1 rapid recency assay was 98.7% (95% CI 97.0 - 99.4) and 99.2% (95% CI 97.1 - 100), respectively. Of the 451 HIV-positive blood samples, 43% were confirmed as recent HIV infections by the Maxim HIV-1 LAg avidity assay. There was high agreement between the Asanté HIV-1 rapid recency assay and the Maxim HIV-1 LAg avidity assay (94.1%, k=0.879, p<0.0001). The sensitivity and specificity of the Asante HIV-1 assay was 89.4% (95% CI 84.0 - 93.0) and 97.7% (95% CI 94.8 - 99.0), respectively.

CONCLUSION

The Asanté HIV-1 rapid recency assay test results demonstrated high accuracy (>90%) compared with the HIV ELISA and rapid assays for determining established infection and the Maxim HIV-1 LAg avidity assay for classifying recent HIV-1 infections. The assay's sensitivity for established infections was below the World Health Organization criteria (<99%) for POC devices. The Asanté HIV-1 rapid recency assay can be used to distinguish between recent and long-term infections, but may not be considered a POC test for determining HIV infection.

Recency of HIV infection, antiretroviral therapy use and viral loads among symptomatic sexually transmitted infection service attendees in South Africa

BACKGROUND

Better integration of HIV and sexually transmitted infection (STI) prevention and treatment services is needed to accelerate progress towards the goal of zero new HIV infections.

OBJECTIVES

To describe HIV positivity, antiretroviral therapy (ART) use, viral suppression and recency of HIV infection among symptomatic STI service attendees at two primary care clinics in South Africa.

METHODS

In a cross-sectional study, male and female STI service attendees presenting with symptoms consistent with STI syndromes were enrolled following informed consent. An interviewer-administered questionnaire was completed and appropriate genital and blood specimens were collected for STI testing and HIV biomarker measurements including recency of infection and antiretroviral (ARV) drug levels. Descriptive statistics were used to describe enrolled attendees, and to determine the proportion of attendees who were HIV-positive, recently infected, taking ART and virally suppressed. HIV-positive attendees with detectable ARVs were considered to be on ART, while those with viral loads (VLs) ≤200 copies/mL were considered virally suppressed.

RESULTS

Of 451 symptomatic attendees whose data were analysed, 93 (20.6%) were HIV-positive, with 15/93 (16.1%) being recently infected. Recent infection was independently associated with genital ulcer disease at presentation, especially ulcers with no detectable STI pathogens. Among the 78 (83.9%) with long-term infection, only 30 (38.5%) were on ART, with 23/30 (76.7%) virally suppressed.

CONCLUSIONS

In a population at risk of HIV transmission, there was a high burden of recent infection and unsuppressed VLs. Incorporating pre-exposure prophylaxis, ART initiation and adherence support into STI services will be necessary for progress towards eliminating HIV transmission.

Opioid prescribing rates from the emergency department: Down but not out

INTRODUCTION

To examine opioid prescribing rates following emergency department (ED) discharge stratified by patient's clinical and demographic characteristics over an 11-year period.

MATERIAL AND METHODS

We used 3.9 million ED visits from commercially insured enrollees and 15.2 million ED visits from Medicaid enrollees aged 12 to 64 over 2005-2016 from the IBM® MarketScan® Research Databases. We calculated rates of opioid prescribing at discharge from the ED and the average number of pills per opioid prescription filled.

RESULTS

Approximately 15-20% of ED visits resulted in opioid prescriptions filled. Rates increased from 2005 into late 2009 and 2010 and then declined steadily through 2016. Prescribing rates were similar for commercially insured and Medicaid enrollees. Being aged 25-54 years was associated with the highest rates of opioid prescriptions being filled. Hydrocodone was the most commonly prescribed opioid, but rates for hydrocodone prescription filling also fell the most. Rates for oxycodone were stable, and rates for tramadol increased. The average number of pills dispensed from prescriptions filled remained steady over the study period at 18-20.

DISCUSSION

Opioid prescribing rates from the ED have declined steadily since 2010 in reversal of earlier trends; however, about 15% of ED patients still received opioid prescriptions in 2016 amidst a national opioid crisis.

CONCLUSIONS

Efforts to reduce opioid prescribing could consider focusing on the pain types, age groups, and regions with high prescription rates identified in this study.

Comparison of 3 Safety-Net Hospital Definitions and Association With Hospital Characteristics

IMPORTANCE

No consensus exists on how to define safety-net hospitals (SNHs) for research or policy decision-making. Identifying which types of hospitals are classified as SNHs under different definitions is key to assessing policies that affect SNH funding.

OBJECTIVE

To examine characteristics of SNHs as classified under 3 common definitions.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis includes noncritical-access hospitals in the Healthcare Cost and Utilization Project State Inpatient Databases from 47 US states for fiscal year 2015, linked to the Centers for Medicare & Medicaid Services Hospital Cost Reports and to the American Hospital Association Annual Survey. Data were analyzed from March 1 through September 30, 2018.

EXPOSURES

Hospital characteristics including organizational characteristics, scope of services provided, and financial attributes.

MAIN OUTCOMES AND MEASURES

Definitions of SNH based on Medicaid and Medicare Supplemental Security Income inpatient days historically used to determine Medicare Disproportionate Share Hospital (DSH) payments; Medicaid and uninsured caseload; and uncompensated care costs. For each measure, SNHs were defined as those within the top quartile for each state.

RESULTS

The 2066 hospitals in this study were distributed across the Northeast (340 [16.5%]), Midwest (587 [28.4%]), South (790 [38.2%]), and West (349 [16.9%]). Concordance between definitions was low; 269 hospitals (13.0%) or fewer were identified as SNHs under any 2 definitions. Uncompensated care captured smaller (200 of 523 [38.2%]) and more rural (65 of 523 [12.4%]) SNHs, whereas DSH index and Medicaid and uncompensated caseload identified SNHs that were larger (264 of 518 [51.0%] and 158 of 487 [32.4%], respectively) and teaching facilities (337 of 518 [65.1%] and 229 of 487 [47.0%], respectively) that provided more essential services than non-SNHs. Uncompensated care also distinguished remarkable financial differences between SNHs and non-SNHs. Under the uncompensated care definition, median (interquartile range [IQR]) bad debt ($27.1 [$15.5-$44.3] vs $12.8 [$6.7-$21.6] per $1000 of operating expenses; P < .001) and charity care ($19.9 [$9.3-$34.1] vs $9.1 [$4.0-$18.7] per $1000 of operating expenses) were twice as high and median (IQR) unreimbursed costs ($32.6 [$12.4-$55.4] vs $23.6 [$9.0-$42.7] per $1000 of operating expenses; P < .001) were 38% higher for SNHs than for non-SNHs. Safety-net hospitals defined by uncompensated care burden had lower median (IQR) total (4.7% [0%-9.9%] vs 5.8% [1.2%-11.2%]; P = .003) and operating (0.3% [-8.0% to 7.2%] vs 2.3% [-3.9% to 8.9%]; P < .001) margins than their non-SNH counterparts, whereas differences between SNH and non-SNH profit margins generally were not statistically significant under the other 2 definitions.

CONCLUSIONS AND RELEVANCE

Different SNH definitions identify hospitals with different characteristics and financial conditions. The new DSH formula, which accounts for uncompensated care, may lead to redistributed payments across hospitals. Our results may inform which types of hospitals will experience funding changes as DSH payment policies evolve.

Opioid Use Disorder and Prescribed Opioid Regimens: Evidence from Commercial and Medicaid Claims, 2005-2015

INTRODUCTION

In response to the US opioid crisis, interventions are being implemented to lower opioid prescribing to reduce opioid misuse and overdose. As opioid prescribing falls, opioid misuse may shift from prescriptions to other, possibly illicit, sources. We examined how the percentage of patients with an opioid use disorder (OUD) diagnosis in a given year without a current opioid prescription changed over a decade among commercially insured enrollees and Medicaid beneficiaries. We also examined how the percentages differed by enrollee demographic factors.

METHODS

We used commercial and Medicaid claims from the IBM MarketScan® databases from 2005 to 2015 to identify enrollees with and without current opioid prescriptions who have been diagnosed with OUD. We measured the percentage of enrollees with OUD without a current opioid prescription by year and demographic factors.

RESULTS

We identified 99,396 enrollee-years with OUD covered by commercial insurance and 60,492 enrollee-years with OUD covered by Medicaid. Among enrollees with OUD, the percentage without a current opioid prescription increased from 37% in 2005 to 49% in 2012 before falling back to 39% in 2015 in the commercial population, and increased from 32% in 2005 to 38% in 2015 in the Medicaid population. Differences in percentages were observed by age, sex, race, and region, particularly among young people where 70 to 89% had OUD without a current prescription.

CONCLUSIONS

Most enrollees with OUD in the data had current opioid prescriptions, suggesting that continuing efforts to reduce misuse of prescribed opioids among patients with prescriptions may be effective. However, a substantial percentage of enrollees with OUD may be obtaining opioids via other, likely illegitimate, channels, particularly younger people, which suggests an opportunity for targeted efforts to reduce opioid diversion.

Changes in hospital service demand, cost, and patient illness severity following health reform

OBJECTIVE

To estimate the effects of the health insurance exchange and Medicaid coverage expansions on hospital inpatient and emergency department (ED) utilization rates, cost, and patient illness severity, and also to test the association between changes in outcomes and the size of the uninsured population eligible for coverage in states.

DATA SOURCES

Healthcare Cost and Utilization Project State Inpatient and Emergency Department Databases, 2011-2015, Nielsen Demographic Data, and the American Community Survey.

STUDY DESIGN

Retrospective study using fixed-effects regression to estimate the effects in expansion and nonexpansion states by age/sex demographic groups.

FINDINGS

In Medicaid expansion states, rates of uninsured inpatient discharges and ED visits fell sharply in many demographic groups. For example, uninsured inpatient discharge rates across groups, except young females, decreased by ≥39 percent per capita on average in expansion states. In nonexpansion states, uninsured utilization rates remained unchanged or increased slightly (0-9.2 percent). Changes in all-payer and private insurance rates were more muted. Changes in inpatient costs per discharge were negative, and all-payer inpatient costs per discharge declined <6 percent in most age/sex groups. The size of the uninsured population eligible for coverage was strongly associated with changes in outcomes. For example, among males aged 35-54 years in expansion states, there was a 0.793 percent decrease in the uninsured discharge rate per unit increase in the coverage expansion ratio (the ratio of the size of the population eligible for coverage to the size of the previously covered population within an age/sex/payer/geographic group).

CONCLUSIONS

Significant shifts in cost per discharge and patient severity were consistent with selective take-up of insurance. The "treatment intensity" of expansions may be useful for anticipating future effects.

The Effects of Medicare Accountable Organizations on Inpatient Mortality Rates

Studies have linked Accountable Care Organizations (ACOs) to improved primary care, but there is little research on how ACOs affect care in other settings. We examined whether Medicare ACOs have improved hospital quality of care, specifically focusing on preventable inpatient mortality. We used 2008-2014 Healthcare Cost and Utilization Project hospital discharge data from 34 states’ Medicare ACO and non-ACO hospitals in conjunction with data from the American Hospital Association Annual Survey and the Survey of Care Systems and Payment. We estimated discharge-level logistic regression models that measured the relationship between ACO affiliation and mortality following admissions for acute myocardial infarction, abdominal aortic aneurysm (AAA) repair, coronary artery bypass grafting, and pneumonia, controlling for patient demographic mix, hospital, and year. Our results suggest that, on average, Medicare ACO hospitals are not associated with improved mortality rates for the studied IQI conditions. Stakeholders may potentially consider providing ACOs with incentives or designing new programs for ACOs to target inpatient mortality reductions.

Medicaid Accountable Care Organizations and Childbirth Outcomes

Some states have adopted Accountable Care Organization (ACO) models to transform their Medicaid programs, but little is known about their impact on health care outcomes and costs. Medicaid ACOs are uniquely positioned to improve childbirth outcomes because of the number of births covered by Medicaid. Using Healthcare Cost and Utilization Project hospital data, we examined the relationship between ACO adoption and (a) neonatal and maternal outcomes, and (b) cost per birth. We compared outcomes in states that have adopted ACO models in their Medicaid programs with adjacent states without ACO models. Implementation of Medicaid ACOs was associated with a moderate reduction in hospital costs per birth and decreased cesarean section rates. Results varied by state. We found no association between Medicaid ACOs and several birth outcomes, including infant inpatient mortality, low birthweight, neonatal intensive care unit utilization, and severe maternal morbidity. Improving these outcomes may require more time or targeted interventions.

Antibiotic Prophylaxis and Incidence of Endocarditis Before and After the 2007 AHA Recommendations

BACKGROUND

The American Heart Association updated its recommendations for antibiotic prophylaxis (AP) to prevent infective endocarditis (IE) in 2007, advising that AP cease for those at moderate risk of IE, but continue for those at high risk.

OBJECTIVES

The authors sought to quantify any change in AP prescribing and IE incidence.

METHODS

High-risk, moderate-risk, and unknown/low-risk individuals with linked prescription and Medicare or commercial health care data were identified in the Truven Health MarketScan databases from May 2003 through August 2015 (198,522,665 enrollee-years of data). AP prescribing and IE incidence were evaluated by Poisson model analysis.

RESULTS

By August 2015, the 2007 recommendation change was associated with a significant 64% (95% confidence interval [CI]: 59% to 68%) estimated fall in AP prescribing for moderate-risk individuals and a 20% (95% CI: 4% to 32%) estimated fall for those at high risk. Over the same period, there was a barely significant 75% (95% CI: 3% to 200%) estimated increase in IE incidence among moderate-risk individuals and a significant 177% estimated increase (95% CI: 66% to 361%) among those at high risk. In unknown/low-risk individuals, there was a significant 52% (95% CI: 46% to 58%) estimated fall in AP prescribing, but no significant increase in IE incidence.

CONCLUSIONS

AP prescribing fell among all IE risk groups, particularly those at moderate risk. Concurrently, there was a significant increase in IE incidence among high-risk individuals, a borderline significant increase in moderate-risk individuals, and no change for those at low/unknown risk. Although these data do not establish a cause-effect relationship between AP reduction and IE increase, the fall in AP prescribing in those at high risk is of concern and, coupled with the borderline increase in IE incidence among those at moderate risk, warrants further investigation.

Early Impact of the Affordable Care Act Coverage Expansion on Safety-Net Hospital Inpatient Payer Mix and Market Shares

OBJECTIVE

To examine the impact of the Affordable Care Act's coverage expansion on safety-net hospitals (SNHs).

STUDY SETTING

Nine Medicaid expansion states.

STUDY DESIGN

Differences-in-differences (DID) models compare payer-specific pre-post changes in inpatient stays of adults aged 19-64 years at SNHs and non-SNHs.

DATA COLLECTION METHODS

2013-2014 Healthcare Cost and Utilization Project State Inpatient Databases.

PRINCIPAL FINDINGS

On average per quarter postexpansion, SNHs and non-SNHs experienced similar relative decreases in uninsured stays (DID = -2.2 percent, p = .916). Non-SNHs experienced a greater percentage increase in Medicaid stays than did SNHs (DID = 13.8 percent, p = .041). For SNHs, the average decrease in uninsured stays (-146) was similar to the increase in Medicaid stays (153); privately insured stays were stable. For non-SNHs, the decrease in uninsured (-63) plus privately insured (-33) stays was similar to the increase in Medicaid stays (105). SNHs and non-SNHs experienced a similar absolute increase in Medicaid, uninsured, and privately insured stays combined (DID = -16, p = .162).

CONCLUSIONS

Postexpansion, non-SNHs experienced a greater percentage increase in Medicaid stays than did SNHs, which may reflect patients choosing non-SNHs over SNHs or a crowd-out of private insurance. More research is needed to understand these trends.

Changes in Hospital Inpatient Utilization Following Health Care Reform

OBJECTIVE

To estimate the effects of 2014 Medicaid expansions on inpatient outcomes.

DATA SOURCES

Health Care Cost and Utilization Project State Inpatient Databases, 2011-2014; population and unemployment estimates.

STUDY DESIGN

Retrospective study estimating effects of Medicaid expansions using difference-in-differences regression. Outcomes included total admissions, referral-sensitive surgical and preventable admissions, length of stay, cost, and patient illness severity.

FINDINGS

In 2014 quarter four, compared with nonexpansion states, Medicaid admissions increased (28.5 percent, p = .006), and uninsured and private admissions decreased (-55.1 percent, p = .001, and -6.6 percent, p = .052), whereas all-payer admissions showed little change. Uninsured expansion effects were negative for preventable admissions (-24.4 percent, p = .068), length of stay (-9.3 percent, p = .039), total cost (-9.2 percent, p = .128), and illness severity (-4.5 percent, p = .397). Significant positive expansion effects were found for Medicaid referral-sensitive surgeries (11.8 percent, p = .021) and patient illness severity (2.3 percent, p = .015). Private and all-payer expansion effects for outcomes other than admission volume were small and mainly nonsignificant (p > .05).

CONCLUSION

Medicaid expansions did not change all-payer admission volumes, but they were associated with increased Medicaid and decreased uninsured volumes. Results suggest those previously uninsured with greater needs for inpatient services were most likely to gain coverage. Compositional changes in uninsured and Medicaid admissions may be due to selection.

Medicare Advantage and Traditional Medicare Hospitalization Intensity and Readmissions

Medicare Advantage plans have incentives and tools to optimize patient care. Therefore, Medicare Advantage hospitalizations may have lower cost and higher quality than similar traditional Medicare hospitalizations. We applied a coarsened matching approach to 2013 Healthcare Cost and Utilization Project hospital discharge data from 22 states to compare hospital cost, length of stay, and readmissions for Traditional Medicare and Medicare Advantage. We found that Medicare Advantage hospitalizations were substantially less expensive and shorter for mental health stays but costlier and longer for injury and surgical stays. We found little difference in the cost and length of medical stays and in readmission rates. One explanation is that Medicare Advantage plans use outpatient settings for many patients with behavioral health conditions and for injury and surgical patients with less complex health needs. Alternatively, the observed differences in behavioral health cost and length of stay may represent skimping on appropriate care.

Impact of Health System Affiliation on Hospital Resource Use Intensity and Quality of Care

OBJECTIVE

To assess the impact of hospital affiliation, centralization, and managed care plan ownership on inpatient cost and quality.

DATA SOURCES

Inpatient discharges from 3,957 community hospitals in 44 states and American Hospital Association Annual Survey data from 2010 to 2012.

STUDY DESIGN

We conducted a retrospective longitudinal regression analysis using hierarchical modeling of discharges clustered within hospitals.

DATA COLLECTION

Detailed discharge data including costs, length of stay, and patient characteristics from the Healthcare Cost and Utilization Project State Inpatient Databases were merged with hospital survey data from the American Hospital Association.

PRINCIPAL FINDINGS

Hospitals affiliated with health systems had a higher cost per discharge and better quality of care compared with independent hospitals. Centralized systems in particular had the highest cost per discharge and longest stays. Independent hospitals with managed care plans had a higher cost per discharge and better quality of care compared with other independent hospitals.

CONCLUSIONS

Increasing prevalence of health systems and hospital managed care ownership may lead to higher quality but are unlikely to reduce hospital discharge costs. Encouraging participation in innovative payment and delivery reform models, such as accountable care organizations, may be more powerful options.

Comparison of chlorine dioxide and dichloroisocyanurate disinfectants for use in the dental setting

AIM

The aim of this study was to compare the antimicrobial properties of a slow release noncorrosive chlorine dioxide with those of sodium dichloroisocyanurate to establish their possible use in the dental settings.

MATERIALS AND METHODS

Disinfectant solutions were prepared according to manufacturers' instructions and tested against Staphylococcus aureus ATCC 29213, Pseudomonas aeruginosa ATCC 27853, Streptococcus mutans NCTC 1044, Candida albicans ATCC 90028, Bacillus subtilis ATCC 15244 spores, Mycobacterium tuberculosis ATCC 25177, Mycobacterium avium subsp. avium ATCC 25291 and Hepatitis B virus using the Standard quantitative suspension test. The shelf-lives of the disinfectants were also determined.

RESULTS

Both disinfectants killed all the test organisms within 30 seconds. B. subtilis spores were killed in 2 and 2.5 minutes by chlorine dioxide and sodium dichloroisocya nurate respectively. When diluted solutions of these disinfectants were stored in screw cap bottles, they retained their activity for at least 30 days.

CONCLUSIONS

Chlorine dioxide and sodium dichloroisocyanurate containing disinfectants can be used in the denta settings for surfaces and heat sensitive instruments. However, chlorine dioxide is advantageous because it is non-corrosive and the effective concentration is lower than that recommended for sodium dichloroisocyanurate.

Defective monocyte chemotaxis in active lepromatous leprosy

This study of monocyte chemotaxis in leprosy patients showed a significant inverse correlation (p less than 0.05) of chemotaxis and the bacterial index (BI) (N = 22). In addition, there was a significant inverse correlation (p less than 0.05) between chemotaxis and the serum levels of anti-phenolic glycolipid-I IgM antibodies (N = 20). Patients taking thalidomide who had a BI greater than or equal to 1 had a significantly greater (p less than 0.001) chemotaxis response than that of patients with the same BI who were not taking thalidomide. No significant decrease in chemotaxis of monocytes from healthy donors was observed when the cells were pre-incubated with serum from 18 leprosy patients. We conclude that monocytes from patients with active lepromatous leprosy not receiving thalidomide have an intrinsic abnormality when assessed by chemotaxis.