Modeling the Declining Positivity Rates for Human Immunodeficiency Virus Testing in New York State.

OBJECTIVE: New York health care providers have experienced declining percentages of positive human immunodeficiency virus (HIV) tests among patients. Furthermore, observed positivity rates are lower than expected on the basis of the national estimate that one-fifth of HIV-infected residents are unaware of their infection. We used mathematical modeling to evaluate whether this decline could be a result of declining numbers of HIV-infected persons who are unaware of their infection, a measure that is impossible to measure directly. DESIGN AND SETTING: A stock-and-flow mathematical model of HIV incidence, testing, and diagnosis was developed. The model includes stocks for uninfected, infected and unaware (in 4 disease stages), and diagnosed individuals. Inputs came from published literature and time series (2006-2009) for estimated new infections, newly diagnosed HIV cases, living diagnosed cases, mortality, and diagnosis rates in New York. MAIN OUTCOME MEASURES: Primary model outcomes were the percentage of HIV-infected persons unaware of their infection and the percentage of HIV tests with a positive result (HIV positivity rate). RESULTS: In the base case, the estimated percentage of unaware HIV-infected persons declined from 14.2% in 2006 (range, 11.9%-16.5%) to 11.8% in 2010 (range, 9.9%-13.1%). The HIV positivity rate, assuming testing occurred independent of risk, was 0.12% in 2006 (range, 0.11%-0.15%) and 0.11% in 2010 (range, 0.10%-0.13%). The observed HIV positivity rate was more than 4 times the expected positivity rate based on the model. CONCLUSIONS: HIV test positivity is a readily available indicator, but it cannot distinguish causes of underlying changes. Findings suggest that the percentage of unaware HIV-infected New Yorkers is lower than the national estimate and that the observed HIV test positivity rate is greater than expected if infected and uninfected individuals tested at the same rate, indicating that testing efforts are appropriately targeting undiagnosed cases.

Substance abuse treatment utilization, HIV risk behaviors, and recruitment among suburban injection drug users in Long Island, New York.

Prevention and treatment of injection drug use remains a public health concern. We used data from the 2005 Centers for Disease Control and prevention National HIV Behavioral Surveillance system to assess substance abuse treatment utilization, risk behaviors, and recruitment processes in a respondent driven sample of suburban injectors. Twelve service utilization and injection risk variables were analyzed using latent class analysis. Three latent classes were identified: low use, low risk; low use, high risk; and high use, moderate/high risk. In multivariate analysis, annual income <$15,000 (adjusted odds ratio (aOR) = 8.19 [95 % confidence interval (CI), 3.83-17.51]) and self-reported hepatitis C virus infection (aOR = 4.32, 95 % CI (1.84-10.17)) were significantly associated with class membership. Homophily, a measure of preferential recruitment showed that injectors with recent treatment utilization appear a more cohesive group than out-of-treatment injectors. Preferentially reaching injection drug users with high risk behaviors and no recent drug treatment history via respondent driven sampling will require future research.

HIV screening practices for living organ donors, New York State, 2010: need for standard policies.

Our survey of kidney and liver transplant centers in New York State found a wide variation among transplant centers in evaluation and screening for HIV risk and infection among prospective living donors. Survey results underscore the need to standardize practices. A recent transmission of human immunodeficiency virus (HIV) from a living donor to a kidney recipient revealed a possible limitation in existing screening protocols for HIV infection in living donors. We surveyed kidney and liver transplant centers (N = 18) in New York State to assess HIV screening protocols for living donors. Although most transplant centers evaluated HIV risk behaviors in living donors, evaluation practices varied widely, as did the extent of HIV testing and prevention counseling. All centers screened living donors for serologic evidence of HIV infection, either during initial evaluation or ≥1 month before surgery; however, only 50% of transplant centers repeated HIV testing within 14 days before surgery for all donors or donors with specific risk behaviors. Forty-four percent of transplant centers used HIV nucleic acid testing (NAT) to screen either all donors or donors with recognized risk behaviors, and 55% never performed HIV NAT. Results suggest the need to standardize evaluation of HIV risk behaviors and prevention counseling in New York State to prevent acquisition of HIV by prospective living organ donors, and to conduct HIV antibody testing and NAT as close to the time of donation as possible to prevent HIV transmission to recipients.

Projections of diagnosed HIV infection in children and adolescents in New York State.

Decreasing mother-to-child transmission is changing the population of children and adolescents with HIV. This project used recent epidemiological data to develop short-term projections of children and adolescents living with diagnosed HIV infection in New York State. A population simulation model was created to project prevalence of diagnosed HIV cases aged 0-19 years by age, sex, race/ethnicity and risk for years 2007-2014. Using 2006 data as the baseline population and 2001-2006 diagnosis and death data, annual diagnoses and deaths were calculated for each age/sex/race/risk category and known cases were 'aged' into the next year. The model produced annual estimates until 2014. The model predicts a decline in the number of persons aged 0-19 years living with diagnosed HIV in New York from 2810 in 2006 to 1431 in 2014, a net decrease of 49%. Living cases with paediatric risk continue to decrease. Cases aged 13-19 with non-paediatric risk increase slowly, leading to a shift in the risk composition of the population. The dominant effect seen in the model is the ageing out of perinatally infected children born before measures to prevent mother-to-child transmission were broadly implemented in the mid- to late 1990s. Changing trends in the young HIV-infected population should be considered in developing public health programmes for HIV prevention and care in New York State for the coming years.

Progress in prevention of mother-to-child transmission of HIV in New York State: 1988-2008.

OBJECTIVES: To assess the outcomes of efforts to prevent mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) made over the last 2 decades in New York State (NYS), through review of data from multiple sources. METHODS: Using available surveillance, laboratory, and program monitoring data, the following were examined for NYS: (1) the rate of prenatal HIV testing, (2) HIV prevalence among childbearing women, (3) maternal prenatal and delivery care, (4) care of HIV-exposed infants, and (5) the rate of MTCT. Trends over time and comparisons among groups were assessed. RESULTS: In NYS, HIV prevalence in childbearing women has declined 70% since its peak in 1989. Rates of prenatal HIV testing have been more than 95% in recent years. Rates of MTCT have decreased significantly; since 2003, transmission in HIV-exposed births has ranged from 1.2% to 2.6% annually. On bivariate analysis, MTCT is more likely to occur with breastfeeding or absence of antiretroviral administration in the prenatal, labor/delivery, and newborn periods. CONCLUSIONS: Mother-to-child HIV transmission has declined dramatically in all groups in NYS. Universal newborn screening data have provided the foundation for identifying HIV-exposed births and for initiating follow-up to track all aspects of MTCT in NYS. Remaining challenges include universal prenatal care, prevention of acquisition of HIV infection during pregnancy, and adherence to antiretroviral therapy.

Return on Investment From Expenditures Incurred to Eliminate Mother-To-Child Transmission Among HIV-Infected Women in New York State: 1998-2013.

BACKGROUND: Eliminating mother-to-child transmission (MTCT) of HIV has been one of New York State's public health priorities, and the goal has been virtually accomplished by meeting criteria established by the Centers for Disease Control and Prevention. METHODS: We use a return on investment (ROI) approach, from the perspective of the state, to compare expenditures incurred to prevent MTCT of HIV in NYS during the period 1998-2013 to benefits realized, as expressed as HIV treatment costs saved from averting an estimated number of HIV infections among newborns. Extrapolating from the 11.5% incidence rate of HIV-infected newborns in 1997, we projected the number of cases of MTCT of HIV that were averted over the 16-year period. A published estimate of lifetime HIV treatment costs was used to estimate HIV treatment costs saved from the averted infections; expenditures for clinical protocols and other services directly associated with preventing MTCT of HIV were also estimated. The ROI was then calculated by dividing program benefits by the expenditures incurred to achieve these benefits. RESULTS: We estimate that 898 cases of MTCT of HIV were averted between 1998 and 2013, resulting in a savings of $321.03 million in HIV treatment costs. Expenditures to achieve these benefits totaled $81.07 million, yielding an ROI of $3.96. CONCLUSIONS: Aside from the human suffering from MTCT of HIV that is averted, expenditures for treatment protocols and interventions to prevent MTCT of HIV are relatively inexpensive and can result in almost 4 times their value in HIV treatment cost savings realized.

Postpartum Loss to HIV Care and HIV Viral Suppression among Previously Diagnosed HIV-Infected Women with a Live Birth in New York State.

Mother-to-child-transmission of HIV in the United States has been greatly reduced, with clear benefits for the child. However, little is known about factors that predict maternal loss to HIV care in the postpartum year. This retrospective cohort study included 980 HIV-positive women, diagnosed with HIV at least one year before pregnancy, who had a live birth during 2008-2010 in New York State. Women who did not meet the following criterion in the 12 months after the delivery-related hospital discharge were considered to be lost to HIV care: two or more laboratory tests (CD4 or HIV viral load), separated by at least 90 days. Adjusted relative risks (aRR) and 95% confidence intervals (CI) for predictors of postpartum loss to HIV care were identified with Poisson regression, solved using generalized estimating equations. Having an unsuppressed (>200 copies/mL) HIV viral load in the postpartum year was also evaluated. Overall, 24% of women were loss to HIV care during the postpartum year. Women with low participation in HIV care during preconception were more likely to be lost to HIV care during the postpartum year (aRR: 2.70; 95% CI: 2.09-3.49). In contrast, having a low birth weight infant was significantly associated with a decreased likelihood of loss to HIV care (aRR: 0.72; 95% CI: 0.53-0.98). While 75% of women were virally suppressed at the last viral load before delivery only 44% were continuously suppressed in the postpartum year; 12% had no viral load test reported in the postpartum year and 44% had at least one unsuppressed viral load test. Lack of engagement in preconception HIV-related health care predicts postpartum loss to HIV care for HIV-positive parturient women. Many women had poor viral control during the postpartum period, increasing the risk of disease progression and infectivity.

Postpartum Human Immunodeficiency Virus Care Among Women Diagnosed During Pregnancy.

OBJECTIVE: To identify factors associated with continuity of care and human immunodeficiency virus (HIV) virologic suppression among postpartum women diagnosed with HIV during pregnancy in New York State. METHODS: This retrospective cohort study was conducted among 228 HIV-infected women diagnosed during pregnancy between 2008 and 2010. Initial receipt of HIV-related medical care (first CD4 or viral load test after diagnosis) was evaluated at 30 days after diagnosis and before delivery. Retention in care (2 or more CD4 or viral load tests, 90 days or greater apart) and virologic suppression (viral load 200 copies/mL or less) were evaluated in the 12 months after hospital discharge. RESULTS: Most women had their initial HIV-related care encounter within 30 days of diagnosis (74%) and before delivery (87%). Of these women, 70% were retained in the first year postpartum. Women waiting more than 30 days for their initial HIV-related care encounter were more likely diagnosed in the first (29%) compared with the third (11%) trimester and were of younger (younger than 25 years, 32%) compared with older (35 years or older, 13%) age. Loss to follow-up within the first year was significantly greater among women diagnosed in the third compared with the first trimester (adjusted relative risk 2.21, 95% confidence interval [CI] 1.41-3.45) and among women who had a cesarean compared with vaginal delivery (adjusted relative risk 1.76, 95% CI 1.07-2.91). Of the 178 women with one or more HIV viral load test in the first year postpartum, 58% had an unsuppressed viral load. CONCLUSION: Despite the high proportion retained in care, many women had poor postpartum virologic control. Robust strategies are needed to increase virologic suppression among newly diagnosed postpartum HIV-infected women.

Timing of entry to care by newly diagnosed HIV cases before and after the 2010 New York State HIV testing law.

Prompt entry to care after HIV diagnosis benefits the infected individual and reduces the likelihood of further transmission of the virus. The New York State HIV Testing Law of 2010 requires diagnosing providers to refer persons newly diagnosed with HIV to follow-up medical care. This study used routinely collected HIV-related laboratory data from the New York State HIV surveillance system to assess whether the fraction of newly diagnosed cases entering care within 90 days of diagnosis increased after the implementation of the law. Laboratory data on 23,302 newly diagnosed cases showed that entry to care within 90 days rose steadily from 72.0% in 2007 to 85.4% in 2012. The rise was observed across all race/ethnic groups, ages, transmission risk groups, sexes, and regions of residence. Logistic regression analyses of entry to care pre-law and post-law, controlling for demographic characteristics, transmission risk, and geographic area, indicate that percentage of newly diagnosed cases entering care within 90 days grew more rapidly in the post-law period. This is consistent with a positive effect of the law on entry to care.

Correlates of routine HIV testing practices: a survey of New York State primary care physicians, 2011.

BACKGROUND: The New York State (NYS) HIV Testing Law of 2010 mandates that medical providers offer HIV testing to patients aged between 13 and 64 years during primary care, to increase the number of people aware of their infection status, and to ensure linkage to medical treatment. To assess physician practices related to this legislation, we conducted a study to identify the frequency and correlates of routine HIV testing behavior among primary care physicians approximately 15 months after the new law went into effect. METHODS: During September 2011 to January 2012, we mailed self-administered surveys to a representative sample of NYS primary care physicians drawn from the AMA Masterfile of Physicians. Questions included physician practices, knowledge, attitudes, and beliefs related to routine HIV testing. Bivariate and multivariate analyses with a sample of 973 physicians were conducted to identify the most influential predictors of routine HIV testing behaviors. RESULTS: A minority of physicians reported "always" or "frequently" practicing behaviors consistent with routine HIV testing, with 41.7% [95% confidence interval (CI): 37.4 to 46.2] routinely offering tests to patients aged 13-64 years, 40.5% (95% CI: 36.3 to 44.8) to new patients, and 33.3% (95% CI: 29.4 to 37.6) to patients during routine physicals. Only 61.4% (95% CI: 57.4 to 65.6) said they had heard of the new law. In multivariate analyses, specialty, perceived barriers, familiarity with the law, and interaction terms representing familiarity by region and self-efficacy by region were significant predictors across the 3 scenarios of routine HIV testing behavior. CONCLUSIONS: Additional technical assistance and training is needed for physicians on adopting routine testing behaviors, minimizing barriers and enhancing skills.

Routine HIV testing capacity, practices, and perceptions among school-based health center providers in New York State after enactment of the 2010 amended HIV testing law.

BACKGROUND: The 2010 New York State (NYS) HIV Testing Law requires that primary care providers routinely offer HIV testing to patients aged 13-64 years, regardless of risk, and link individuals with HIV to medical care. School-based health centers (SBHCs) are in a position to offer HIV screening to a significant proportion of youth. One year after the law went into effect, we conducted a study to assess whether NYS SBHCs implemented these provisions. METHODS: Medical providers from 83 NYS SBHCs, serving students age 13 and older, participated in a Web-based survey regarding school-based health center capacity for and implementation of routine HIV testing, linkage to care, attitudes, and barriers. RESULTS: On-site HIV testing was reported to be available at 71% of SBHCs. Linkages to age-appropriate HIV care were reported to be available at 85% of SBHCs. The routine offer of HIV testing for eligible students was reported to be implemented at 55% of SBHCs. Forty-one percent reported that HIV testing was offered to at least half of eligible students during the 2010-2011 school year. New York City and high school providers were more likely to report the routine offer of HIV testing, on-site testing, linkages to care, perceive students as willing to test, indicate fewer barriers, and report having offered testing to a majority of eligible students in the previous year. CONCLUSIONS: Many SBHCs have adopted key provisions of the amended NYS HIV Testing Law. Additional assistance may be needed to achieve full implementation; however, especially among SBHCs serving younger populations and those located outside New York City.

Policy modeling to support administrative decisionmaking on the New York state HIV testing law.

A recent New York law requires medical providers to offer HIV tests as part of routine care. We developed a system dynamics simulation model of the HIV testing and care system to help administrators understand the law's potential epidemic impact, resource needs, strategies to improve implementation, and appropriate outcome indicators for future policy evaluations once postlaw data become available. Policy modeling allowed us to synthesize information from numerous sources including quantitative administrative data sets and practitioners' content expertise, structure the information to be viewed both numerically and visually, and organize consensus for decisionmaking purposes. This case illustrates how policy modeling can provide an integrated framework for administrators to examine policy problems in complex systems, particularly when data time lags limit pre--post comparisons and key outcomes cannot be measured directly.

New York State 2010 HIV testing law: an evaluation of testing rates using laboratory data.

As of September 2010, New York State (NYS) Public Health Law mandates the offer of HIV testing to all persons aged 13-64 years receiving hospital or primary care services. Changes in the number of HIV tests 13 months before and after law enactment were assessed using HIV test volume data from 166 laboratories holding NYS permits to conduct HIV testing on specimens originating in NYS. Compared with the pre-enactment baseline, overall HIV testing volume increased by 13% following enactment, with the volume of conventional and rapid HIV screening tests increasing by 12.0% and 13.7%, respectively. These data suggest that testing law is having an impact consistent with the legislative intent to increase HIV testing in NYS. Monitoring should be continued to assess testing trends across a variety of health care venues to identify and address additional barriers to HIV testing access.

HIV test offers and acceptance: New York State findings from the behavioral risk factor surveillance system and the National HIV behavioral surveillance, 2011-2012.

BACKGROUND: The New York State HIV testing law requires that patients aged 13-64 years be offered HIV testing in health care settings. We investigated the extent to which HIV testing was offered and accepted during the 24 months after law enactment. METHODS: We added local questions to the Behavioral Risk Factor Surveillance System (BRFSS) and the National HIV Behavioral Surveillance (NHBS) surveys asking respondents aged 18-64 years whether they were offered an HIV test in health care settings, and whether they had accepted testing. Statewide prevalence estimates of test offers and acceptance were obtained from a combined 2011-2012 BRFSS sample (N = 6,223). Local estimates for 2 high-risk populations were obtained from NHBS 2011 men who have sex with men (N = 329) and 2012 injection drug users (N = 188) samples. RESULTS: BRFSS data showed that 73% of New Yorkers received care in any health care setting in the past 12 months, of whom 25% were offered an HIV test. Sixty percent accepted the test when offered. The levels of test offer increased from 20% to 29% over time, whereas acceptance levels decreased from 68% to 53%. NHBS data showed that 81% of men who have sex with men received care, of whom 43% were offered an HIV test. Eighty-eight percent accepted the test when offered. Eighty-five percent of injection drug users received care, of whom 63% were offered an HIV test, and 63% accepted the test when offered. CONCLUSIONS: We found evidence of partial and increasing implementation of the HIV testing law. Importantly, these studies demonstrated New Yorkers' willingness to accept an offered HIV test as part of routine care in health care settings.

Mandating the offer of HIV testing in New York: simulating the epidemic impact and resource needs.

BACKGROUND: A 2010 New York law requires that patients aged 13-64 years be offered HIV testing in routine medical care settings. Past studies report the clinical outcomes, cost-effectiveness, and budget impact of expanded HIV testing nationally and within clinics but have not examined how state policies affect resource needs and epidemic outcomes. METHODS: A system dynamics model of HIV testing and care was developed, where disease progression and transmission differ by awareness of HIV status, engagement in care, and disease stage. Data sources include HIV surveillance, Medicaid claims, and literature. The model projected how alternate implementation scenarios would change new infections, diagnoses, linkage to care, and living HIV cases over 10 years. RESULTS: Without the law, the model projects declining new infections, newly diagnosed cases, individuals newly linked to care, and fraction of undiagnosed cases (reductions of 62.8%, 59.7%, 54.1%, and 57.8%) and a slight increase in living diagnosed cases and individuals in care (2.2% and 6.1%). The law will further reduce new infections, diagnosed AIDS cases, and the fraction undiagnosed and initially increase and then decrease newly diagnosed cases. Outcomes were consistent across scenarios with different testing offer frequencies and implementation times but differed according to the level of implementation. CONCLUSIONS: A mandatory offer of HIV testing may increase diagnoses and avert infections but will not eliminate the epidemic. Despite declines in new infections, previously diagnosed cases will continue to need access to antiretroviral therapy, highlighting the importance of continued funding for HIV care.

Transmitted antiretroviral drug resistance in New York State, 2006-2008: results from a new surveillance system.

BACKGROUND: HIV transmitted drug resistance (TDR) is a public health concern because it has the potential to compromise antiretroviral therapy (ART) at the population level. In New York State, high prevalence of TDR in a local cohort and a multiclass resistant case cluster led to the development and implementation of a statewide resistance surveillance system. METHODOLOGY: We conducted a cross-sectional analysis of the 13,109 cases of HIV infection that were newly diagnosed and reported in New York State between 2006 and 2008, including 4,155 with HIV genotypes drawn within 3 months of initial diagnosis and electronically reported to the new resistance surveillance system. We assessed compliance with DHHS recommendations for genotypic resistance testing and estimated TDR among new HIV diagnoses. PRINCIPAL FINDINGS: Of 13,109 new HIV diagnoses, 9,785 (75%) had laboratory evidence of utilization of HIV-related medical care, and 4,155 (43%) had a genotype performed within 3 months of initial diagnosis. Of these, 11.2% (95% confidence interval [CI], 10.2%-12.1%) had any evidence of TDR. The proportion with mutations associated with any antiretroviral agent in the NNRTI, NRTI or PI class was 6.3% (5.5%-7.0%), 4.3% (3.6%-4.9%) and 2.9% (2.4%-3.4%), respectively. Multiclass resistance was observed in <1%. TDR did not increase significantly over time (p for trend = 0.204). Men who have sex with men were not more likely to have TDR than persons with heterosexual risk factor (OR 1.0 (0.77-1.30)). TDR to EFV+TDF+FTC and LPV/r+TDF+FTC regimens was 7.1% (6.3%-7.9%) and 1.4% (1.0%-1.8%), respectively. CONCLUSIONS/SIGNIFICANCE: TDR appears to be evenly distributed and stable among new HIV diagnoses in New York State; multiclass TDR is rare. Less than half of new diagnoses initiating care received a genotype per DHHS guidelines.