Reward-motivated memories influence new learning across development

Previously rewarding experiences can influence choices in new situations. Past work has demonstrated that existing reward associations can either help or hinder future behaviors and that there is substantial individual variability in the transfer of value across contexts. Developmental changes in reward sensitivity may also modulate the impact of prior reward associations on later goal-directed behavior. The current study aimed to characterize how reward associations formed in the past affected learning in the present from childhood to adulthood. Participants completed a reinforcement learning paradigm using high- and low-reward stimuli from a task completed 24 h earlier, as well as novel stimuli, as choice options. We found that prior high-reward associations impeded learning across all ages. We then assessed how individual differences in the prioritization of high- versus low-reward associations in memory impacted new learning. Greater high-reward memory prioritization was associated with worse learning performance for previously high-reward relative to low-reward stimuli across age. Adolescents also showed impeded early learning regardless of individual differences in high-reward memory prioritization. Detrimental effects of previous reward on choice behavior did not persist beyond learning. These findings indicate that prior reward associations proactively interfere with future learning from childhood to adulthood and that individual differences in reward-related memory prioritization influence new learning across age.

Brain region- and sex-specific transcriptional profiles of microglia

Microglia are resident macrophages of the brain, performing roles related to brain homeostasis, including modulation of synapses, trophic support, phagocytosis of apoptotic cells and debris, as well as brain protection and repair. Studies assessing morphological and transcriptional features of microglia found regional differences as well as sex differences in some investigated brain regions. However, markers used to isolate microglia in many previous studies are not expressed exclusively by microglia or cannot be used to identify and isolate microglia in all contexts. Here, fluorescent activated cell sorting was used to isolate cells expressing the microglia-specific marker TMEM119 from prefrontal cortex (PFC), striatum, and midbrain in mice. RNA-sequencing was used to assess the transcriptional profile of microglia, focusing on brain region and sex differences. We found striking brain region differences in microglia-specific transcript expression. Most notable was the distinct transcriptional profile of midbrain microglia, with enrichment for pathways related to immune function; these midbrain microglia exhibited a profile similar to disease-associated or immune-surveillant microglia. Transcripts more highly expressed in PFC isolated microglia were enriched for synapse-related pathways while microglia isolated from the striatum were enriched for pathways related to microtubule polymerization. We also found evidence for a gradient of expression of microglia-specific transcripts across the rostral-to-caudal axes of the brain, with microglia extracted from the striatum exhibiting a transcriptional profile intermediate between that of the PFC and midbrain. We also found sex differences in expression of microglia-specific transcripts in all 3 brain regions, with many selenium-related transcripts more highly expressed in females across brain regions. These results suggest that the transcriptional profile of microglia varies between brain regions under homeostatic conditions, suggesting that microglia perform diverse roles in different brain regions and even based on sex.

Determinants of worry using the SARS-CoV-19 worry (CoV-Wo) scale among United States residents

We sought to develop a brief Severe Acute Respiratory Syndrome Coronavirus 2-related worry (CoV-Wo) scale to understand COVID-19-related worry among adults in the United States. We also aimed to model key determinants of worry in the early stage of the COVID-19 pandemic in the United States. A total of 806 participants completed an online survey in late March 2020. Exploratory and confirmatory factor analyses assessed scale structure. Factor analysis stratified by depression was used to assess measurement invariance. Linear regression models examined COVID-19-related worry determinants. The CoV-Wo scale exhibited good reliability (α = 0.80) and a two-factor structure: health (α = 0.83) and resources (α = 0.71). The full scale and both subscales were higher among participants who stopped working due to COVID-19 and those with depression. Perception of quality medical care if infected with COVID-19 was associated with reduced worry. The CoV-Wo scale is a low burden assessment of COVID-19-related worry, that captures common worries in domains affected by COVID-19 and can be used to develop psychosocial resources.

CB1 R and iNOS are distinct players promoting pulmonary fibrosis in Hermansky-Pudlak syndrome

Hermansky-Pudlak syndrome (HPS) is a rare genetic disorder which, in its most common and severe form, HPS-1, leads to fatal adult-onset pulmonary fibrosis (PF) with no effective treatment. We evaluated the role of the endocannabinoid/CB1 R system and inducible nitric oxide synthase (iNOS) for dual-target therapeutic strategy using human bronchoalveolar lavage fluid (BALF), lung samples from patients with HPS and controls, HPS-PF patient-derived lung fibroblasts, and bleomycin-induced PF in pale ear mice (HPS1ep/ep ). We found overexpression of CB1 R and iNOS in fibrotic lungs of HPSPF patients and bleomycin-infused pale ear mice. The endocannabinoid anandamide was elevated in BALF and negatively correlated with pulmonary function parameters in HPSPF patients and pale ear mice with bleomycin-induced PF. Simultaneous targeting of CB1 R and iNOS by MRI-1867 yielded greater antifibrotic efficacy than inhibiting either target alone by attenuating critical pathologic pathways. Moreover, MRI-1867 treatment abrogated bleomycin-induced increases in lung levels of the profibrotic interleukin-11 via iNOS inhibition and reversed mitochondrial dysfunction via CB1 R inhibition. Dual inhibition of CB1 R and iNOS is an effective antifibrotic strategy for HPSPF.

HIV-1 proviral landscape characterization varies by pipeline analysis

INTRODUCTION

HIV rebounds after cessation of antiretroviral therapy, representing a barrier to cure. To better understand the virus reservoir, analysis pipelines have been developed that categorize proviral sequences as intact or defective, and further determine the precise nature of the sequence defects that may be present. We investigated the effects that different analysis pipelines had on the characterization of HIV-1 proviral sequences.

METHODS

We used single genome amplification to generate near full-length (NFL) HIV-1 proviral DNA sequences, defined as amplicons greater than 8000 base pairs in length, isolated from peripheral blood mononuclear cells (PBMC) of treated suppressed participants with HIV-1. Amplicons underwent direct next-generation single genome sequencing and were analysed using four HIV-1 proviral characterization pipelines. Sequences were characterized as intact or defective; defective sequences were assessed for the number and types of defects present. To confirm and extend our findings, 691 proviruses from the Proviral Sequence Database (PSD) were analysed and the ProSeq-IT tool of the PSD was used to characterize both the participant and PSD proviruses.

RESULTS AND DISCUSSION

Virus sequences derived from thirteen ART-treated virologically suppressed participants with HIV were studied. A total of 693 HIV-1 proviral sequences were generated, 282 of which were NFL. An average of 53 sequences per participant was analysed. We found that proviruses often harbour multiple sequence defect types (mean 2.7, 95% confidence interval [CI] 2.5, 3.0); the elimination order used by each pipeline affected the percentage of proviruses allotted into each defect category. These differences varied between participants, depending on the number of defect categories present in a given provirus sequence. Pipeline-specific differences in characterizing the HIV-1 5' untranslated region (5' UTR) led to an overestimation of the number of intact NFL proviral sequences, a finding corroborated in the independent PSD analysis. A comparison of the four published pipelines to ProSeq-IT found that ProSeq IT was more likely to characterize proviruses as intact.

CONCLUSIONS

The choice of pipeline used for HIV-1 provirus landscape analysis may bias the classification of defective sequences. To improve the comparison of provirus characterizations across research groups, the development of a consensus elimination pipeline should be prioritized.

The longitudinal association between depression, anxiety symptoms and HIV outcomes, and the modifying effect of alcohol dependence among ART clients with hazardous alcohol use in Vietnam

INTRODUCTION

Mental health disorders may negatively impact HIV outcomes, such as viral suppression (VS) and antiretroviral (ART) adherence among people with HIV (PWH) with hazardous alcohol use. This study evaluates the longitudinal association between depression, anxiety symptoms, VS and complete ART adherence among ART clients with hazardous alcohol use in Vietnam; and examines alcohol dependence as a modifier in this association.

METHODS

This was a secondary data analysis of a trial for hazardous drinking ART clients in Thai Nguyen, Vietnam. From March 2016 to May 2018, 440 ART clients with an Alcohol Use Disorders Identification Test-Concise (AUDIT-C) score ≥4 for men and ≥3 for women were enrolled. Individuals were randomized to either a combined intervention, a brief intervention or a standard of care. Data on sociodemographics, depression, anxiety symptoms, alcohol use, VS and ART adherence were collected at baseline, three, six, and twelve months. Generalized estimating equation models controlling for intervention exposure were used to estimate time-lagged associations. Risk ratios were estimated using Poisson regression with robust variance estimation.

RESULTS

The mean age of participants was 40.2. The majority was male (96.8%), had at least some secondary school education (85.0%) and had a history of injection drug use (80.9%). No overall effect of depression and anxiety symptoms on VS was observed. When stratified by time, increased anxiety symptoms at six months were associated with VS at 12 months (adjusted risk ratio (aRR) = 1.09; 95% CI 1.02 to 1.17). An increase in depression or anxiety symptoms was associated with a decreased probability of complete ART adherence (depression symptoms: aRR = 0.95; 95% CI: 0.91 to 0.99; anxiety symptoms: aRR = 0.93; 85% CI: 0.88 to 0.99). The negative effects of anxiety symptoms on ART adherence were stronger among participants with alcohol dependence, compared to those without.

CONCLUSIONS

Depression and anxiety symptoms had no overall effect on VS, although they were associated with a lower probability of complete ART adherence. Interventions focusing on mental healthcare for PWH with hazardous alcohol use are needed, and integration of mental healthcare and alcohol reduction should be implemented in HIV primary care settings.

Project Khanya: results from a pilot randomized type 1 hybrid effectiveness-implementation trial of a peer-delivered behavioural intervention for ART adherence and substance use in HIV care in South Africa

INTRODUCTION

South Africa (SA) has the highest number of people living with HIV (PLWH) globally, and a significant burden of alcohol and other drug use (AOD). Although integrating AOD treatment into HIV care may improve antiretroviral therapy (ART) adherence, this is not typically routine practice in SA or other low-resource settings. Identifying interventions that are feasible and acceptable for implementation is critical to improve HIV and AOD outcomes.

METHODS

A pilot randomized hybrid type 1 effectiveness-implementation trial (N = 61) was conducted to evaluate the feasibility and acceptability of Khanya, a task-shared, peer-delivered behavioral intervention to improve ART adherence and reduce AOD in HIV care in SA. Khanya was compared to enhanced treatment as usual (ETAU), a facilitated referral to on-site AOD treatment. Implementation outcomes, defined by Proctor's model, included feasibility, acceptability, appropriateness and fidelity. Primary pilot effectiveness outcomes were ART adherence at post-treatment (three months) measured via real-time electronic adherence monitoring, and AOD measured using biomarker and self-report assessments over six months. Data collection was conducted from August 2018 to April 2020.

RESULTS AND DISCUSSION

Ninety-one percent of participants (n = 56) were retained at six months. The intervention was highly feasible, acceptable, appropriate and delivered with fidelity (>90% of components delivered as intended by the peer). There was a significant treatment-by-time interaction for ART adherence (estimate = -0.287 [95% CI = -0.507, -0.066]), revealing a 6.4 percentage point increase in ART adherence in Khanya, and a 22.3 percentage point decline in ETAU. Both groups evidenced significant reductions in alcohol use measured using phosphatidylethanol (PEth) (F(2,101) = 4.16, p = 0.01), significantly decreased likelihood of self-reported moderate or severe AOD (F(2,104) = 7.02, p = 0.001), and significant declines in alcohol use quantity on the timeline follow-back (F(2,102) = 21.53, p < 0.001). Among individuals using drugs and alcohol, there was a greater reduction in alcohol use quantity in Khanya compared to ETAU over six months (F(2,31) = 3.28, p = 0.05).

CONCLUSIONS

Results of this pilot trial provide initial evidence of the feasibility and acceptability of the Khanya intervention for improving adherence in an underserved group at high risk for ongoing ART non-adherence and HIV transmission. Implementation results suggest that peers may be a potential strategy to extend task-sharing models for behavioral health in resource-limited, global settings.

An evaluation of assumptions underlying respondent-driven sampling and the social contexts of sexual and gender minority youth participating in HIV clinical trials in the United States

INTRODUCTION

Respondent-driven sampling (RDS) has been an effective sampling strategy for HIV research in many settings, but has had limited success among some youth in the United States. We evaluated a modified RDS approach for sampling Black and Latinx sexual and gender minority youth (BLSGMY) and explored how lived experiences and social contexts of BLSGMY youth may impact traditional RDS assumptions.

METHODS

RDS was implemented in three US cities, Baltimore, Philadelphia and Washington DC, to engage BLSGMY aged 15 to 24 years in HIV prevention or care intervention trials. RDS was modified to include targeted seed recruitment from venues, Internet and health clinics, and provided options for electronic or paper coupons. Qualitative interviews were conducted among a sub-sample of RDS participants to explore their experiences with RDS. Interviews were coded using RDS assumptions as an analytic framework.

RESULTS

Between August 2017 and October 2019, 405 participants were enrolled, 1670 coupons were distributed, with 133 returned, yielding a 0.079 return rate. The maximum recruitment depth was four waves among seeds that propagated. Self-reported median network size was 5 (IQR 2 to 10) and reduced to 3 (IQR 1 to 5) when asked how many peers were seen in the past 30 days. Qualitative interviews (n = 27) revealed that small social networks, peer trust and targeted referral of peers with certain characteristics challenged network, random recruitment, and reciprocity assumptions of RDS. HIV stigma and research hesitancy were barriers to participation and peer referral. Other situational factors, such as phone ownership and access to reliable transportation, reportedly created challenges for referred peers to participate in research.

CONCLUSIONS

Small social networks and varying relationships with peers among BLSGMY challenge assumptions that underlie traditional RDS. Modified RDS approaches, including those that incorporate social media, may support recruitment for community-based research but may challenge assumptions of reciprocal relationships. Research hesitancy and situational barriers are relevant and must be addressed across any sampling method and study design that includes BLSGMY in the United States.

A cluster-randomized controlled trial of a combination HIV risk reduction and microfinance intervention for female sex workers who use drugs in Kazakhstan

INTRODUCTION

Female sex workers (FSW) who use drugs are a key population at risk of HIV in Kazakhstan, and face multiple structural barriers to HIV prevention. More research is needed on the role of structural interventions such as microfinance (MF) in reducing HIV risk. This paper describes the results of a cluster-randomized controlled trial to test the efficacy of a combination HIVRR + MF intervention in reducing biologically confirmed STIs and HIV risk behaviours.

METHODS

This study took place from May 2015 to October 2018 in two cities in Kazakhstan. We screened 763 participants for eligibility and enrolled 354 FSW who use drugs. Participants were randomized in cohorts to receive either a four-session HIVRR intervention, or that same intervention plus 30 additional sessions of financial literacy training, vocational training and asset-building through a matched-savings programme. Repeated behavioural and biological assessments were conducted at baseline, 3-, 6- and 12-months post-intervention. Biological and behavioural primary outcomes included HIV/STI incidence, sexual risk behaviours and drug use risk behaviours, evaluated over the 12-month period.

RESULTS

Over the 12-month follow-up period, few differences in study outcomes were noted between arms. There was only one newly-detected HIV case, and study arms did not significantly differ on any STI incidence. At post-intervention assessments compared to baseline, both HIVRR and HIVRR + MF participants significantly reduced sexual and drug use risk behaviours, and showed improvements in financial outcomes, condom use attitudes and self-efficacy, social support, and access to medical care. In addition, HIVRR + MF participants showed a 72% greater reduction in the number of unprotected sex acts with paying partners at the six-month assessment (IRR = IRR = 0.28, 95% CI = 0.08, 0.92), and a 10% greater reduction in the proportion of income from sex work at the three-month assessment (b = -0.10, 95% CI = -0.17, -0.02) than HIVRR participants did. HIVRR + MF participants also showed significantly improved performance on financial self-efficacy compared to HIVRR over the 12-month follow-up period.

CONCLUSIONS

Compared to a combination HIVRR + MF intervention, a robust HIVRR intervention alone may be sufficient to reduce sexual and drug risk behaviours among FSW who use drugs. There may be structural limitations to the promise of microfinance for HIV risk reduction among this population.

Associations of cannabis use disorder with cognition, brain structure, and brain function in African Americans

Although previous studies have highlighted associations of cannabis use with cognition and brain morphometry, critical questions remain with regard to the association between cannabis use and brain structural and functional connectivity. In a cross-sectional community sample of 205 African Americans (age 18-70) we tested for associations of cannabis use disorder (CUD, n = 57) with multi-domain cognitive measures and structural, diffusion, and resting state brain-imaging phenotypes. Post hoc model evidence was computed with Bayes factors (BF) and posterior probabilities of association (PPA) to account for multiple testing. General cognitive functioning, verbal intelligence, verbal memory, working memory, and motor speed were lower in the CUD group compared with non-users (p < .011; 1.9 < BF < 3,217). CUD was associated with altered functional connectivity in a network comprising the motor-hand region in the superior parietal gyri and the anterior insula (p < .04). These differences were not explained by alcohol, other drug use, or education. No associations with CUD were observed in cortical thickness, cortical surface area, subcortical or cerebellar volumes (0.12 < BF < 1.5), or graph-theoretical metrics of resting state connectivity (PPA < 0.01). In a large sample collected irrespective of cannabis used to minimize recruitment bias, we confirm the literature on poorer cognitive functioning in CUD, and an absence of volumetric brain differences between CUD and non-CUD. We did not find evidence for or against a disruption of structural connectivity, whereas we did find localized resting state functional dysconnectivity in CUD. There was sufficient proof, however, that organization of functional connectivity as determined via graph metrics does not differ between CUD and non-user group.

Bingeing on High-Fat Food Enhances Evoked Dopamine Release and Reduces Dopamine Uptake in the Nucleus Accumbens

OBJECTIVE

Binge-eating disorder (BED) disrupts dopamine neuron function, in part by altering dopamine transporter (DAT) activity. This study characterized the effects of high-fat bingeing on presynaptic dopamine terminals and tested the hypothesis that acute low-dose amphetamine would restore DAT function.

METHODS

C57BL/6 mice were given limited access (LimA) to a high-fat diet (2 h/d, 3 d/wk) or standard chow (control). After 6 weeks, ex vivo fast-scan cyclic voltammetry was used to characterize dopamine-terminal adaptations in the nucleus accumbens. Prior to undergoing fast-scan cyclic voltammetry, some mice from each group were given amphetamine (0.5 mg/kg intraperitoneally).

RESULTS

Escalation of high fat intake, termed bingeing, occurred in the LimA group and coincided with increased phasic dopamine release, reduced dopamine uptake rates, and increased dopamine receptor 2 (D2 ) autoreceptor function. Acute amphetamine selectively reversed dopamine uptake changes in the LimA group and restored the potency of amphetamine to inhibit uptake.

CONCLUSIONS

High-fat bingeing enhanced dopaminergic signaling in the nucleus accumbens by promoting phasic dopamine release and reducing clearance. This study's data show that amphetamine was efficacious in restoring impaired DAT function caused by high-fat bingeing but did not reduce dopamine release to normal. These presynaptic changes should be considered if amphetamine-like dopamine releasers are used as treatments for BED.

Improving transitions of care for patients initiated on buprenorphine for opioid use disorder from the emergency departments in King County, Washington

STUDY OBJECTIVE

Opioid use disorder (OUD) is on the rise nationwide with increasing emergency department (ED) visits and deaths secondary to overdose. Although previous research has shown that patients who are started on buprenorphine in the ED have increased engagement in addiction treatment, access to on-demand medications for OUD is still limited, in part because of the need for linkages to outpatient care. The objective of this study is to describe emergency and outpatient providers' perception of local barriers to transitions of care for ED-initiated buprenorphine patients.

METHODS

Purposive sampling was used to recruit key stakeholders, identified as physicians, addiction specialists, and hospital administrators, from 10 EDs and 11 outpatient clinics in King County, Washington. Twenty-one interviews were recorded and transcribed and then coded using an integrated deductive and inductive content analysis approach by 2 team members to verify accuracy of the analysis. Interview guides and coding were informed by the Consolidated Framework for Implementation Research (CFIR), which provides a structure of domains and constructs associated with effective implementation of evidence-based practice.

RESULTS

From the 21 interviews with emergency and outpatient providers, this study identified 4 barriers to transitions of care for ED-initiated buprenorphine patients: scope of practice, prescribing capacity, referral incoordination, and loss to follow-up.

CONCLUSION

Next steps for implementation of this intervention in a community setting include establishing a standard of care for treatment and referral for ED patients with OUD, increasing buprenorphine prescribing capacity, creating a central repository for streamlined referrals and follow-up, and supporting low-barrier scheduling and navigation services.

Estimating HIV transmissions in a large U.S. clinic-based sample: effects of time and syndemic conditions

INTRODUCTION

Little is known about onward HIV transmissions from people living with HIV (PLWH) in care. Antiretroviral therapy (ART) has increased in potency, and treatment as prevention (TasP) is an important component of ending the epidemic. Syndemic theory has informed modelling of HIV risk but has yet to inform modelling of HIV transmissions.

METHODS

Data were from 61,198 primary HIV care visits for 14,261 PLWH receiving care through the Centers for AIDS Research (CFAR) Network of Integrated Clinical Systems (CNICS) at seven United States (U.S.) sites from 2007 to 2017. Patient-reported outcomes and measures (PROs) of syndemic conditions - depressive symptoms, anxiety symptoms, drug use (opiates, amphetamines, crack/cocaine) and alcohol use - were collected approximately four to six months apart along with sexual behaviours (mean = 4.3 observations). Counts of syndemic conditions, HIV sexual risk group and time in care were modelled to predict estimated HIV transmissions resulting from sexual behaviour and viral suppression status (HIV RNA < 400/mL) using hierarchical linear modelling.

RESULTS

Patients averaged 0.38 estimated HIV transmissions/100 patients/year for all visits with syndemic conditions measured (down from 0.83, first visit). The final multivariate model showed that per 100 patients, each care visit predicted 0.05 fewer estimated transmissions annually (95% confidence interval (CI): 0.03 to 0.06; p < 0.0005). Cisgender women, cisgender heterosexual men and cisgender men of undisclosed sexual orientation had, respectively, 0.47 (95% CI: 0.35 to 0.59; p < 0.0005), 0.34 (95% CI: 0.20 to 0.49; p < 0.0005) and 0.22 (95% CI: 0.09 to 0.35; p < 0.005) fewer estimated HIV transmissions/100 patients/year than cisgender men who have sex with men (MSM). Each within-patient syndemic condition predicted 0.18 estimated transmissions/100 patients/year (95% CI: 0.12 to 0.24; p < 0.0005). Each between-syndemic condition predicted 0.23 estimated HIV transmissions/100 patients/year (95% CI: 0.17 to 0.28; p < 0.0005).

CONCLUSIONS

Estimated HIV transmissions among PLWH receiving care in well-resourced U.S. clinical settings varied by HIV sexual risk group and decreased with time in care, highlighting the importance of TasP efforts. Syndemic conditions remained a significant predictor of estimated HIV transmissions notwithstanding the effects of HIV sexual risk group and time in care.

A comparison of the effectiveness of respondent-driven and venue-based sampling for identifying undiagnosed HIV infection among cisgender men who have sex with men and transgender women in Tijuana, Mexico

BACKGROUND

Efforts to increase HIV testing, diagnosis and care are critical to curbing HIV epidemics among cisgender men who have sex with men (MSM) and transgender women (TW) in low- and middle-income countries (LMIC). We compared the effectiveness of respondent-driven sampling (RDS) and venue-based sampling (VBS) for identifying previously undiagnosed HIV infection among MSM and TW in Tijuana, Mexico.

METHODS

Between March 2015 and December 2018, we conducted RDS within the social networks of MSM and TW and VBS at venues frequented by MSM and TW to socialize and meet sexual partners. Those reached by RDS/VBS who reported at least 18 years of age, anal sex with MSM or TW, and no previous HIV diagnosis were eligible for HIV testing.

RESULTS

Of those screened following recruitment via RDS (N = 1232; 98.6% MSM; 1.3% TW), 60.8% (749/1232) were eligible for HIV testing and 97.5% (730/749) were tested for HIV infection, which led to the identification of 36 newly diagnosed HIV infections (4.9%). Of those screened following recruitment via VBS (N = 2560; 95.2% MSM; 4.6% TW), 56.5% (1446/2560) were eligible for HIV testing and 92.8% (1342/1446) were tested for HIV infection, which led to the identification of 82 newly diagnosed HIV infections (6.1%). The proportion of new HIV diagnoses did not differ by recruitment method (ratio = 0.81, 95% confidence interval: 0.55 to 1.18). Compared to those recruited via RDS, those tested following recruitment via VBS were younger, more likely to identify as gay, and more likely to identify as TW. Compared to those recruited via VBS, those newly diagnosed with HIV infection following recruitment via RDS reported higher levels of internalized stigma and were more likely to report injection drug use and a history of deportation from the United States.

CONCLUSIONS

Despite RDS and VBS being equally effective for identifying undiagnosed HIV infection, each recruitment method reached different subgroups of MSM and TW in Tijuana. Our findings suggest that there may be benefits to using both RDS and VBS to increase the identification of previously undiagnosed HIV infection and ultimately support HIV care engagement among MSM and TW in Mexico and other similar LMIC.

Psychiatric genomics research during the COVID-19 pandemic: A survey of Psychiatric Genomics Consortium researchers

Between April 20, 2020 and June 19, 2020 we conducted a survey of the membership of the Psychiatric Genomics Consortium (PGC) to explore the impact of COVID-19 on their research and academic careers. A total of 123 individuals responded representing academic ranks from trainee to full professor, tenured and fixed-term appointments, and all genders. The survey included both quantitative and free text responses. Results revealed considerable concern about the impact of COVID-19 on research with the greatest concern reported by individuals in nonpermanent positions and female researchers. Concerns about the availability of funding and the impact of the pandemic on career progression were commonly reported by early career researchers. Recommendations for institutions, organizations such as the PGC, as well as individual senior investigators have been provided to ensure that the futures of early career investigators, especially those underrepresented in academic medicine such as women and underrepresented minorities, are not disproportionately disadvantaged by the COVID-19 pandemic.

Comparison of a web-push survey research protocol with a mailed paper and pencil protocol in the Monitoring the Future panel survey

AIMS

The experiment tested the effects of a web-push survey research protocol, compared with the standard mailed paper-and-pencil protocol, among young adults aged 19-30 years in the 'Monitoring the Future' (MTF) longitudinal study.

DESIGN, SETTING AND PARTICIPANTS

The US-based MTF study has measured substance use trends among young adults in panel samples followed biennially, using consistent mailed survey procedures from 1977 to 2017. In 2018, young adult participants in the MTF longitudinal component scheduled to be surveyed at ages 19-30 in 2018 (from high school senior cohorts of 2006-17, n = 14 709) were randomly assigned to receive the standard mail/paper survey procedures or new web-push procedures.

MEASUREMENTS

Primary outcomes were responding to the survey and prevalence estimates for past 30-day use of alcohol, cigarettes, marijuana and illicit drugs.

FINDINGS

The web-push response rate was 39.07% [95% confidence interval (CI) = 37.889, 40.258]; this was significantly better than the standard MTF response rate of 35.12% (95% CI = 33.964, 36.285). After adjusting for covariates, the web-push condition was associated with a 19% increase in the odds of responding compared with standard MTF (adjusted odds ratio = 1.188; 95% CI = 1.096, 1.287). Substance use prevalence estimates were very similar and differences became negligible when using attrition weights and controlling for socio-demographic characteristics.

CONCLUSIONS

The web-push protocol produced a higher response rate than the mailed pencil and paper protocol in the Monitoring the Future panel study, without substantially affecting estimates of substance use once attrition weights and socio-demographic variables were factored in.

Sex differences and effects of the estrous stage on hippocampal-prefrontal theta communications

Effective communication between the mammalian hippocampus and neocortex is essential to certain cognitive-behavioral tasks critical to survival in a changing environment. Notably, functional synchrony between local field potentials (LFPs) of the ventral hippocampus (vHPC) and the medial prefrontal cortex (mPFC) within the theta band (4-12 Hz) underlies innate avoidance behavior during approach-avoidance conflict tasks in male rodents. However, the physiology of vHPC-mPFC communications in females remains unestablished. Furthermore, little is known about how mPFC subdivisions functionally interact in the theta band with hippocampal subdivisions in both sexes in the absence of task demand. Given the established roles of biological sex and gonadal hormone status on innate avoidance behaviors and neuronal excitability, here, we characterize the effects of biological sex and female estrous stage on hippocampal-prefrontal (HPC-mPFC) theta signaling in freely moving female and male rats. LFPs from vHPC, dorsal hippocampus (dHPC), mPFC-prelimbic (PrL), and mPFC-infralimbic (IL) were simultaneously recorded during spontaneous exploration of a familiar arena. Data suggest that theta phase and power in vHPC preferentially synchronize with PrL; conversely, dHPC and IL preferentially synchronize. Males displayed greater vHPC-PrL theta synchrony than females, despite similar regional frequency band power and inter-regional coherence. Additionally, several significant estrous-linked changes in HPC-mPFC theta dynamics were observed. These findings support the hypothesis that HPC-mPFC theta signaling is sensitive to both biological sex and female estrous stage. These findings establish novel research avenues concerning sex as a biological variable and effects of gonadal hormone status on HPC-mPFC network activity as it pertains to threat evaluation biomarkers.

Comparison of effectiveness and cost for different HIV screening strategies implemented at large urban medical centre in the United States

INTRODUCTION

Incident HIV infections persist in the United States (U.S.) among marginalized populations. Targeted and cost-efficient testing strategies can help in reaching HIV elimination. This analysis compares the effectiveness and cost of three HIV testing strategies in a high HIV burden area in the U.S. in identifying new HIV infections.

METHODS

We performed a cost analysis comparing three HIV testing strategies in Chicago: (1) routine screening (RS) in an inpatient and outpatient setting, (2) modified partner services (MPS) among networks of the recently HIV infected and diagnosed, and (3) a respondent drive sampling (RDS)-based social network (SN) approach targeting young African-American men who have sex with men. All occurred at the same academic medical centre during the following times: routine testing, 2011 to 2016; MPS, 2013 to 2016; SN: 2013 to 2014. Costs were in 2016 dollars and included personnel, HIV testing, training, materials, overhead. Outcomes included cost per test, HIV-positive test and new diagnosis. Sensitivity analyses were performed to assess the impact of population demographics.

RESULTS

The RS programme completed 57,308 HIV tests resulting in 360 (0.6%) HIV-positive tests and 165 new HIV diagnoses (0.28%). The MPS completed 146 HIV tests, resulting in 79 (54%) HIV-positive tests and eight new HIV diagnoses (5%). The SN strategy completed 508 HIV tests, resulting in 210 (41%) HIV-positive tests and 37 new HIV diagnoses (7.2%). Labour accounted for the majority of costs in all strategies. The estimated cost per new HIV diagnosis was $16,773 for the RS programme, $61,418 for the MPS programme and $15,683 for the SN testing programme. These costs were reduced for the RS and MPS strategies in sensitivity analyses limiting testing efficacy to the highest prevalence patient populations ($2,841 and $33,233 respectively).

CONCLUSIONS

The SN strategy yielded the highest proportion of new diagnoses, followed closely by the MPS programme. Both the SN strategy and RS programme were comparable in the cost per new diagnosis. A simultaneous approach that consists of RS in combination with SN testing may be most effective for identifying new HIV infections in settings with heterogeneous epidemics with both high rates of HIV prevalence and HIV testing.

Validating a predictive model of cannabinoid inheritance with feral, clinical, and industrial Cannabis sativa

PREMISE

How genetic variation within a species affects phytochemical composition is a fundamental question in botany. The ratio of two specialized metabolites in Cannabis sativa, tetrahydrocannabinol (THC) and cannabidiol (CBD), can be grouped into three main classes (THC-type, CBD-type, and intermediate type). We tested a genetic model associating these three groups with functional and nonfunctional alleles of the cannabidiolic acid synthase gene (CBDAS).

METHODS

We characterized cannabinoid content and assayed CBDAS genotypes of >300 feral C. sativa plants in Minnesota, United States. We performed a test cross to assess CBDAS inheritance. Twenty clinical cultivars obtained blindly from the National Institute on Drug Abuse and 12 Canadian-certified grain cultivars were also examined.

RESULTS

Frequencies of CBD-type, intermediate-type, and THC-type feral plants were 0.88, 0.11, and 0.01, respectively. Although total cannabinoid content varied substantially, the three groupings were perfectly correlated with CBDAS genotypes. Genotype frequencies observed in the test cross were consistent with codominant Mendelian inheritance of the THC:CBD ratio. Despite significant mean differences in total cannabinoid content, CBDAS genotypes blindly predicted the THC:CBD ratio among clinical cultivars, and the same was true for industrial grain cultivars when plants exhibited >0.5% total cannabinoid content.

CONCLUSIONS

Our results extend the generality of the inheritance model for THC:CBD to diverse C. sativa accessions and demonstrate that CBDAS genotyping can predict the ratio in a variety of practical applications. Cannabinoid profiles and associated CBDAS segregation patterns suggest that feral C. sativa populations are potentially valuable experimental systems and sources of germplasm.

Fine-mapping and QTL tissue-sharing information improves the reliability of causal gene identification

The integration of transcriptomic studies and genome-wide association studies (GWAS) via imputed expression has seen extensive application in recent years, enabling the functional characterization and causal gene prioritization of GWAS loci. However, the techniques for imputing transcriptomic traits from DNA variation remain underdeveloped. Furthermore, associations found when linking eQTL studies to complex traits through methods like PrediXcan can lead to false positives due to linkage disequilibrium between distinct causal variants. Therefore, the best prediction performance models may not necessarily lead to more reliable causal gene discovery. With the goal of improving discoveries without increasing false positives, we develop and compare multiple transcriptomic imputation approaches using the most recent GTEx release of expression and splicing data on 17,382 RNA-sequencing samples from 948 post-mortem donors in 54 tissues. We find that informing prediction models with posterior causal probability from fine-mapping (dap-g) and borrowing information across tissues (mashr) can lead to better performance in terms of number and proportion of significant associations that are colocalized and the proportion of silver standard genes identified as indicated by precision-recall and receiver operating characteristic curves. All prediction models are made publicly available at predictdb.org.

Situating the Continuum of Overdose Risk in the Social Determinants of Health: A New Conceptual Framework

Policy Points This article reconceptualizes our understanding of the opioid epidemic and proposes six strategies that address the epidemic's social roots. In order to successfully reduce drug-related mortality over the long term, policymakers and public health leaders should develop partnerships with people who use drugs, incorporate harm reduction interventions, and reverse decades of drug criminalization policies.

CONTEXT

Drug overdose is the leading cause of injury-related death in the United States. Synthetic opioids, predominantly illicit fentanyl and its analogs, surpassed prescription opioids and heroin in associated mortality rates in 2016. Unfortunately, interventions fail to fully address the current wave of the opioid epidemic and often omit the voices of people with lived experiences regarding drug use. Every overdose death is a culmination of a long series of policy failures and lost opportunities for harm reduction.

METHODS

In this article, we conducted a scoping review of the opioid literature to propose a novel framework designed to foreground social determinants more directly into our understanding of this national emergency. The "continuum of overdose risk" framework is our synthesis of the global evidence base and is grounded in contemporary theories, models, and policies that have been successfully applied both domestically and internationally.

FINDINGS

De-escalating overdose risk in the long term will require scaling up innovative and comprehensive solutions that have been designed through partnerships with people who use drugs and are rooted in harm reduction.

CONCLUSIONS

Without recognizing the full drug-use continuum and the role of social determinants, the current responses to drug overdose will continue to aggravate the problem they are trying to solve.

Interrupted Time Series of User-centered Clinical Decision Support Implementation for Emergency Department-initiated Buprenorphine for Opioid Use Disorder

OBJECTIVES

Adoption of emergency department (ED) initiation of buprenorphine (BUP) for opioid use disorder (OUD) into routine emergency care has been slow, partly due to clinicians' unfamiliarity with this practice and perceptions that it is complicated and time-consuming. To address these barriers and guide emergency clinicians through the process of BUP initiation, we implemented a user-centered computerized clinical decision support system (CDS). This study was conducted to assess the feasibility of implementation and to evaluate the preliminary efficacy of the intervention to increase the rate of ED-initiated BUP.

METHODS

An interrupted time series study was conducted in an urban, academic ED from April 2018 to February 2019 (preimplementation phase), March 2019 to August 2019 (implementation phase), and September 2019 to December 2019 (maintenance phase) to study the effect of the intervention on adult ED patients identified by a validated electronic health record (EHR)-based computable phenotype consisting of structured data consistent with potential cases of OUD who would benefit from BUP treatment. The intervention offers flexible CDS for identification of OUD, assessment of opioid withdrawal, and motivation of readiness to start treatment and automates EHR activities related to ED initiation of BUP (including documentation, orders, prescribing, and referral). The primary outcome was the rate of ED-initiated BUP. Secondary outcomes were launch of the intervention, prescription for naloxone at ED discharge, and referral for ongoing addiction treatment.

RESULTS

Of the 141,041 unique patients presenting to the ED over the preimplementation and implementation phases (i.e., the phases used in primary analysis), 906 (574 preimplementation and 332 implementation) met OUD phenotype and inclusion criteria. The rate of BUP initiation increased from 3.5% (20/574) in the preimplementation phase to 6.6% (22/332) in the implementation phase (p = 0.03). After the temporal trend of the number of physician's with X-waiver training and other covariates were adjusted for, the relative risk of BUP initiation rate was 2.73 (95% confidence interval [CI] = 0.62 to 12.0, p = 0.18). Similarly, the number of unique attendings who initiated BUP increased modestly 7/53 (13.0%) to 13/57 (22.8%, p = 0.10) after offering just-in-time training during the implementation period. The rate of naloxone prescribed at discharge also increased (6.5% preimplementation and 11.5% implementation; p < 0.01). The intervention received a system usability scale score of 82.0 (95% CI = 76.7 to 87.2).

CONCLUSION

Implementation of user-centered CDS at a single ED was feasible, acceptable, and associated with increased rates of ED-initiated BUP and naloxone prescribing in patients with OUD and a doubling of the number of unique physicians adopting the practice. We have implemented this intervention across several health systems in an ongoing trial to assess its effectiveness, scalability, and generalizability.

Differences in HIV risk and healthcare engagement factors in Filipinx transgender women and cisgender men who have sex with men who reported being HIV negative, HIV positive or HIV unknown

INTRODUCTION

Understanding HIV risk and healthcare engagement of at-risk individuals by HIV status is vital to informing HIV programmes in settings where the HIV epidemic is rapidly expanding like the Philippines. This study examined differences in HIV risk and healthcare engagement factors among Filipinx transgender women and cisgender men who have sex with men (trans-WSM and cis-MSM respectively) who self-reported being HIV negative, HIV positive or HIV unknown.

METHODS

Between 2018 and 2019, we conducted Project #ParaSaAtin, an online cross-sectional survey that examined the structural, social and behavioural factors impacting HIV services among Filipinx trans-WSM and cis-MSM (n = 318). We performed multinomial regression procedures to determine factors associated with HIV status (with HIV-negative referent). Co-variates included participant demographics, experiences of social marginalization, HIV risk, healthcare engagement and alcohol and substance problems.

RESULTS

Self-reported HIV status of the sample was as follows: 38% HIV negative, 34% HIV positive and 28% HIV unknown. Relative to HIV-negative respondents, HIV-positive respondents were more likely to be older (25- to 29-year-old adjusted risk ratio [aRRR]=5.08, 95% Confidence Interval [95% CI] = 1.88 to 13.72; 30- to 34-year-old aRRR = 4.11, 95% CI = 1.34 to 12.58; and 35 + years old aRRR = 8.13, 95% CI = 2.40 to 27.54, vs. 18 to 25 years old respectively), to live in Manila (aRRR = 5.89, 95% CI = 2.20 to 15.72), exhibit hazardous drinking (aRRR = 2.87, 95% CI = 1.37 to 6.00) and problematic drug use (aRRR = 2.90, 95% CI = 1.21 to 7.13). HIV-positive respondents were less likely to identify as straight (aRRR = 0.13, 95% CI = 0.02 to 0.72), and were more likely to avoid HIV services due to lack of anti-lesbian, gay, bisexual and transgender (LGBT) discrimination policies (aRRR = 0.37, 95% CI = 0.14 to 0.90). Relative to HIV-negative respondents, HIV-unknown respondents were less educated (some college aRRR = 0.10, 95% CI = 0.02 to 0.37, beyond college aRRR = 0.31, 95% CI = 0.09 to 0.99, vs. high school or below respectively), had lower HIV knowledge (aRRR = 0.30, 95% CI = 0.20 to 0.71), and were less communicative about safer sex (ARR = 0.29, 95% CI = 0.09 to 0.92). Moreover, HIV-unknown respondents were also more likely to have avoided HIV services due to cost (aRRR = 4.46, 95% CI = 1.73 to 11.52).

CONCLUSIONS

This study highlights differences in HIV risks and healthcare engagement by HIV status. These findings show different barriers exist per HIV status group, and underscore the need to address Filipinx trans-WSM and cis-MSM's poor engagement in HIV services in the Philippines.

Within-person variability in curiosity during daily life and associations with well-being

OBJECTIVE

Curiosity promotes engagement in novel situations and the accruement of resources that promote well-being. An open question is the extent to which curiosity lability, the degree to which curiosity fluctuates over short timescales, impacts well-being.

METHOD

We use data from a 21-day daily diary as well as trait measures in 167 participants (mean age = 25.37 years, SD = 7.34) to test (a) the importance of curiosity lability for depression, flourishing, and life satisfaction, (b) day-to-day associations among curiosity and happiness, depressed mood, anxiety, and physical activity, and (c) the role of day's mood as a mediator between physical activity and curiosity.

RESULTS

We observe positive associations among curiosity lability and depression, as well as negative associations among curiosity lability and both life satisfaction and flourishing. Curiosity is higher on days of greater happiness and physical activity, and lower on days of greater depressed mood. We find evidence consistent with day's depressed mood and happiness being mediators between physical activity and curiosity.

CONCLUSIONS

Greater consistency in curiosity is associated with well-being. We identify several potential sources of augmentation and blunting of curiosity in daily life and provide support for purported mechanisms linking physical activity to curiosity via mood.

Impact of low-level viraemia on virological failure among Asian children with perinatally acquired HIV on first-line combination antiretroviral treatment: a multicentre, retrospective cohort study

INTRODUCTION

The clinical relevance of low-level viraemia (LLV) and virological outcomes among children living with HIV (CLHIV) remains controversial. This study aimed to determine the impact of LLV on virological failure (VF) among Asian CLHIV on first-line combination antiretroviral therapy (cART).

METHODS

CLHIV aged <18 years, who were on first-line cART for ≥12 months, and had virological suppression (two consecutive plasma viral load [pVL] <50 copies/mL) were included. Those who started treatment with mono/dual antiretroviral therapy, had a history of treatment interruption >14 days, or received treatment and care at sites with a pVL lower limit of detection >50 copies/mL were excluded. LLV was defined as a pVL 50 to 1000 copies/mL, and VF as a single pVL >1000 copies/mL. Baseline was the time of the second pVL < 50 copies/mL. Cox proportional hazards models were performed to assess the association between LLV and VF.

RESULTS

From January 2008 to September 2016, 508 CLHIV (55% female) were eligible for the study. At baseline, the median age was 9.6 (IQR: 7.0 to 12.3) years, cART duration was 1.4 (IQR: 1.3 to 1.8) years, 97% of CLHIV were on non-nucleoside reverse transcriptase inhibitor-based regimens, and the median CD4 was 25% (IQR: 20% to 30%). Over a median follow-up time of 6.0 (IQR: 3.1 to 8.9) years from baseline, 86 CLHIV (17%) had ever experienced LLV, of whom 32 (37%) had multiple LLV episodes. Female sex, living in Malaysia (compared to Cambodia), having family members other than biological parents/grandparents as a primary caregiver, and baseline CD4 < 25% increased risk of LLV. Overall, 115 children (23%) developed VF, corresponding to a rate of 4.0 (95%CI: 3.4 to 4.9) per 100 person-years of follow-up (PYFU). VF was greater among children who had ever experienced LLV compared with those who maintained virological suppression throughout the study period (8.9 vs. 3.3 per 100 PYFU; p < 0.001). In multivariable analyses, ever experiencing LLV was associated with increased risk of subsequent VF (adjusted hazard ratio: 3.01; 95%CI: 1.97 to 4.60).

CONCLUSIONS

LLV increased the risk of subsequent VF among Asian CLHIV who had previously been suppressed on first-line cART. Adherence interventions and additional targeted pVL monitoring may be warranted among children with LLV to facilitate early detection of VF.

Trends in CD4 and viral load testing 2005 to 2018: multi-cohort study of people living with HIV in Southern Africa

INTRODUCTION

The World Health Organization (WHO) recommends a CD4 cell count before starting antiretroviral therapy (ART) to detect advanced HIV disease, and routine viral load (VL) testing following ART initiation to detect treatment failure. Donor support for CD4 testing has declined to prioritize access to VL monitoring. We examined trends in CD4 and VL testing among adults (≥15 years of age) starting ART in Southern Africa.

METHODS

We analysed data from 14 HIV treatment programmes in Lesotho, Malawi, Mozambique, South Africa, Zambia and Zimbabwe in 2005 to 2018. We examined the frequency of CD4 and VL testing, the percentage of adults with CD4 or VL tests, and among those having a test, the percentage starting ART with advanced HIV disease (CD4 count <200 cells/mm3 ) or failing to suppress viral replication (>1000 HIV-RNA copies/mL) after ART initiation. We used mixed effect logistic regression to assess time trends adjusted for age and sex.

RESULTS

Among 502,456 adults, the percentage with CD4 testing at ART initiation decreased from a high of 78.1% in 2008 to a low of 38.0% in 2017; the probability declined by 14% each year (odds ratio (OR) 0.86; 95% CI 0.86 to 0.86). Frequency of CD4 testing also declined. The percentage starting ART with advanced HIV disease declined from 83.3% in 2005 to 23.5% in 2018; each year the probability declined by 20% (OR 0.80; 95% CI 0.80 to 0.81). VL testing after starting ART varied; 61.0% of adults in South Africa and 10.7% in Malawi were tested, but fewer than 2% were tested in the other four countries. The probability of VL testing after ART start increased only modestly each year (OR 1.06; 95% CI 1.05 to 1.06). The percentage with unsuppressed VL was 8.6%. There was no evidence of a decrease in unsuppressed VL over time (OR 1.00; 95% CI 0.99 to 1.01).

CONCLUSIONS

CD4 cell counting declined over time, including testing at the start of ART, despite the fact that many patients still initiated ART with advanced HIV disease. Without CD4 testing and expanded VL testing many patients with advanced HIV disease and treatment failure may go undetected, threatening the effectiveness of ART in sub-Saharan Africa.

High levels of viral load monitoring and viral suppression under Treat All in Rwanda - a cross-sectional study

INTRODUCTION

Aiming to reach UNAIDS 90-90-90 targets, nearly all sub-Saharan African countries have expanded antiretroviral therapy (ART) to all people living with HIV (PLWH) (Treat All). Few published data exist on viral load testing and viral suppression under Treat All in this region. We assessed proportions of patients with available viral load test results and who were virally suppressed, as well as factors associated with viral suppression, among PLWH in 10 Rwandan health centres after Treat All implementation.

METHODS

Cross-sectional study during 2018 of adults (≥15 years) engaged in HIV care at 10 Rwandan health centres. Outcomes were being on ART (available ART initiation date in the study database, with no ART discontinuation prior to 1 January 2018), retained on ART (≥2 post-ART health centre visits ≥90 days apart during 2018), available viral load test results (viral load measured in 2018 and available in study database) and virally suppressed (most recent 2018 viral load <200 copies/mL). We used modified Poisson regression models accounting for clustering by health centre to determine factors associated with being virally suppressed.

RESULTS

Of 12,238 patients, 7050 (58%) were female and 1028 (8%) were aged 15 to 24 years. Nearly all patients (11,933; 97%) were on ART, of whom 11,198 (94%) were retained on ART. Among patients retained on ART, 10,200 (91%) had available viral load results; of these 9331 (91%) were virally suppressed. Viral suppression was less likely among patients aged 15 to 24 compared to >49 years (adjusted prevalence ratio (aPR): 0.83, 95% CI 0.76 to 0.90 and those with pre-ART CD4 counts of <200 compared to ≥500 cells/mm3 (aPR: 0.92, 95% CI 0.90 to 0.93). There was no statistically significant difference in viral suppression among patients who entered after Treat All implementation compared to those who enrolled before 2010 (aPR 0.98, 95% CI 0.94 to 1.03).

CONCLUSIONS

In this large cohort of Rwandan PLWH receiving HIV care after Treat All implementation, patients in study health centres have surpassed the third UNAIDS 90-90-90 target. To ensure all PLWH fully benefit from ART, additional efforts should focus on improving ART adherence among younger persons.

Statins for atherosclerotic cardiovascular disease prevention in people living with HIV in Thailand: a cost-effectiveness analysis

INTRODUCTION

People living with HIV (PLHIV) have an elevated risk of atherosclerotic cardiovascular disease (CVD) compared to their HIV-negative peers. Expanding statin use may help alleviate this burden. However, the choice of statin in the context of antiretroviral therapy is challenging. Pravastatin and pitavastatin improve cholesterol levels in PLHIV without interacting substantially with antiretroviral therapy. They are also more expensive than most statins. We evaluated the cost-effectiveness of pravastatin and pitavastatin for the primary prevention of CVD among PLHIV in Thailand who are not currently using lipid-lowering therapy.

METHODS

We developed a discrete-state microsimulation model that randomly selected (with replacement) individuals from the TREAT Asia HIV Observational Database cohort who were aged 40 to 75 years, receiving antiretroviral therapy in Thailand, and not using lipid-lowering therapy. The model simulated each individual's probability of experiencing CVD. We evaluated: (1) treating no one with statins; (2) treating everyone with pravastatin 20mg/day (drug cost 7568 Thai Baht ($US243)/year) and (3) treating everyone with pitavastatin 2 mg/day (drug cost 8182 Baht ($US263)/year). Direct medical costs and quality-adjusted life-years (QALYs) were assigned in annual cycles over a 20-year time horizon and discounted at 3% per year. We assumed the Thai healthcare sector perspective.

RESULTS

Pravastatin was estimated to be less effective and less cost-effective than pitavastatin and was therefore dominated (extended) by pitavastatin. Patients receiving pitavastatin accumulated 0.042 additional QALYs compared with those not using a statin, at an extra cost of 96,442 Baht ($US3095), giving an incremental cost-effectiveness ratio of 2,300,000 Baht ($US73,812)/QALY gained. These findings were sensitive to statin costs and statin efficacy, pill burden, and targeting of PLHIV based on CVD risk. At a willingness-to-pay threshold of 160,000 Baht ($US5135)/QALY gained, we estimated that pravastatin would become cost-effective at an annual cost of 415 Baht ($US13.30)/year and pitavastatin would become cost-effective at an annual cost of 600 Baht ($US19.30)/year.

CONCLUSIONS

Neither pravastatin nor pitavastatin were projected to be cost-effective for the primary prevention of CVD among PLHIV in Thailand who are not currently using lipid-lowering therapy. We do not recommend expanding current use of these drugs among PLHIV in Thailand without substantial price reduction.

Frequency of health-care utilization by adults who use illicit drugs: a systematic review and meta-analysis

AIMS

To summarize evidence on the frequency and predictors of health-care utilization among people who use illicit drugs.

DESIGN

Systematic search of MEDLINE, EMBASE and PsychINFO for observational studies reporting health-care utilization published between 1 January 2000 and 3 December 2018. We conducted narrative synthesis and meta-analysis following a registered protocol (identifier: CRD42017076525).

SETTING AND PARTICIPANTS

People who use heroin, powder cocaine, crack cocaine, methamphetamine, amphetamine, ecstasy/3,4-methyl​enedioxy​methamphetamine (MDMA), cannabis, hallucinogens or novel psychoactive substances; have a diagnosis of 'substance use disorder'; or use drug treatment services.

MEASUREMENTS

Primary outcomes were the cumulative incidence (risk) and rate of care episodes in three settings: primary care, hospital admissions (in-patient) and emergency department (ED).

FINDINGS

Ninety-two studies were included, 84% from North America and Australia. Most studies focused on people using heroin, methamphetamine or crack cocaine, or who had a diagnosis of drug dependence. We were able to conduct a meta-analysis of rates across 25 studies reporting ED episodes and 25 reporting hospital admissions, finding pooled rates of 151 [95% confidence interval (CI) = 114-201] and 41 (95% CI = 30-57) per 100 person-years, respectively; on average 4.8 and 7.1 times more often than the general population. Heterogeneity was very high and was not explained by drugs used, country of study, recruitment setting or demographic characteristics. Predictors of health-care utilization were consistent across studies and included unstable housing, drug injection and mental health problems. Opioid substitution therapy was consistently associated with reduced ED presentation and hospital admission. There was minimal research on health-care utilization by people using ecstasy/MDMA, powder cocaine, hallucinogens or novel psychoactive substances.

CONCLUSIONS

People who use illicit drugs are admitted to emergency department or hospital several times more often than the general population.

Integrating HIV pre-exposure prophylaxis and harm reduction among men who have sex with men and transgender women to address intersecting harms associated with stimulant use: a modelling study

INTRODUCTION

Among men who have sex with men (MSM) and transgender women (TW), stimulant use is high and has been associated with an increased risk of HIV infection, suicide and cardiovascular disease (CVD) mortality. We used epidemic modelling to investigate these intersecting health harms among MSM/TW in Lima, Peru and assess whether they could be mitigated by prioritizing HIV pre-exposure prophylaxis (PrEP) and harm reduction interventions among MSM/TW who use stimulants.

METHODS

We adapted a dynamic model of HIV transmission among MSM/TW in Lima to incorporate stimulant use and increased HIV risk, suicide and CVD mortality. Among 6% to 24% of MSM/TW using stimulants (mostly cocaine), we modelled an increased risk of unprotected anal sex (RR = 1.35 [95%CI: 1.17 to 1.57]) obtained from local data, and increased risk of suicide (SMR = 6.26 [95%CI: 2.84 to 13.80]) and CVD (SMR = 1.83 [95%CI: 0.39 to 8.57]) mortality associated with cocaine use based on a global systematic review. We estimated the proportion of health harms occurring among MSM/TW who use stimulants in the next year (01-2020/01-2021). We also investigated the 10-year impact (01-2020/01-2030) of: (1) PrEP prioritization for stimulant-using MSM/TW compared to random allocation, and (2) integrating PrEP with a theoretical intervention halving stimulant-associated risk.

RESULTS

MSM/TW in Lima will experience high HIV incidence, suicide mortality and CVD mortality (1.6/100 py, and 0.018/100 py, 0.13/100 py respectively) in 2020. Despite stimulant using MSM/TW comprising an estimated 9.5% (95%CI: 7.8 to 11.5) of all MSM/TW, in the next year, 11% 95%CI (i.e. 2.5% to 97.5% percentile) 10% to 13%) of new HIV infections, 39% (95%CI: 18% to 60%) of suicides and 15% (95%CI: 3% to 44%) of CVD deaths could occur among this group. Scaling up PrEP among all stimulant using MSM/TW could prevent 19% (95%CI: 11% to 31%) more HIV infections over 10 years compared to random allocation. Integrating PrEP and an intervention to halve stimulant-associated risks could reduce new HIV infections by 20% (95%CI: 10% to 37%), suicide deaths by 14% (95%CI: 5% to 27%) and CVD deaths by 3% (95%CI: 0% to 16%) over a decade.

CONCLUSIONS

MSM/TW who use stimulants experience a disproportionate burden of health harms. Prioritizing PrEP based on stimulant use, in addition to sexual behaviour/gender identity criteria, could increase its impact. Integrated substance use, harm reduction, mental health and HIV care among MSM/TW is needed.

Modelling integrated antiretroviral treatment and harm reduction services on HIV and overdose among people who inject drugs in Tijuana, Mexico

INTRODUCTION

The HIV epidemic in Tijuana, Mexico is concentrated in key populations, including people who inject drugs (PWID). However, HIV interventions among PWID are minimal, and federal funding was provided for compulsory abstinence programmes associated with HIV and overdose. Alternatively, opioid agonist therapy reduces overdose, reincarceration, HIV, while improving antiretroviral therapy (ART) outcomes. We assessed potential impact and synergies of scaled-up integrated ART and opioid agonist therapy, compared to scale-up of each separately, and potential harms of compulsory abstinence programmes on HIV and fatal overdose among PWID in Tijuana.

METHODS

We developed a dynamic model of HIV transmission and overdose among PWID in Tijuana. We simulated scale-up of opioid agonist therapy from zero to 40% coverage among PWID. We evaluated synergistic benefits of an integrated harm reduction and ART scale-up strategy (40% opioid agonist therapy coverage and 10-fold ART recruitment), compared to scale-up of each intervention alone or no scale-up of low coverage ART and no harm reduction). We additionally simulated compulsory abstinence programmes (associated with 14% higher risk of receptive syringe sharing and 76% higher odds of overdose) among PWID.

RESULTS

Without intervention, HIV incidence among PWID could increase from 0.72 per 100 person-years (PY) in 2020 to 0.92 per 100 PY in 2030. Over ten years, opioid agonist therapy scale-up could avert 31% (95% uncertainty interval (UI): 18%, 46%) and 22% (95% UI: 10%, 28%) new HIV infections and fatal overdoses, respectively, with the majority of HIV impact from the direct effect on HIV transmission due to low ART coverage. Integrating opioid agonist therapy and ART scale-up provided synergistic benefits, with opioid agonist therapy effects on ART recruitment/retention averting 9% more new infections compared to ART scale-up alone. The intervention strategy could avert 48% (95% UI: 26%, 68%) of new HIV infections and one-fifth of fatal overdoses over ten years. Conversely, compulsory abstinence programmes could increase HIV and overdoses.

CONCLUSIONS

Integrating ART with opioid agonist therapy could provide synergistic benefits and prevent HIV and overdoses among PWID in Tijuana, whereas compulsory abstinence programmes could cause harm. Policymakers should consider the benefits of integrating harm reduction and HIV services for PWID.

Women from afar: an observational study of demographic characteristics and mortality among foreign-born women living with HIV in the Women's Interagency HIV Study (WIHS) in the United States 1994-2016

INTRODUCTION

Foreign-born persons comprise ~13% of the US population. Immigrants, especially women, often face a complex set of social and structural factors that negatively impact health outcomes including greater risk of HIV infection. We described socio-demographic, clinical and immunological characteristics and AIDs and non-AIDS death among foreign-born women living with HIV (FBWLWH) participating in the US Women's Interagency HIV Study (WIHS) in the US from 1994 to 2016. We hypothesized that FBW will experience higher AIDS-related mortality compared to US-born women (USBW).

METHODS

The WIHS is a multicenter prospective observational cohort study of mostly women living with HIV (WLWH). The primary exposure in this analysis, which focused on 3626 WLWH, was self-reported country of birth collapsed into foreign-born and US born. We assessed the association of birthplace with categorized demographic, clinical and immunological characteristics, and AIDS/non-AIDS mortality of WLWH, using chi-squared tests. Proportional hazard models examined the association of birthplace with time from enrolment to AIDS and non-AIDS death.

RESULTS

Of the 628 FBW, 13% were born in Africa, 29% in the Caribbean and 49% in Latin America. We observed significant differences by HIV status in socio-demographic, clinical and immunological characteristics and mortality. For both AIDS and non-AIDS caused deaths FBW WLWH had lower rates of death. Adjusting for year of study enrolment and other demographic/clinical characteristics mitigated FBW's statistical survival advantage in AIDS deaths Relative Hazard (RH = 0.91 p = 0.53), but did not substantively change the survival advantage in non-AIDS deaths RH = 0.33, p < 0.0001).

CONCLUSION

Foreign-born WLWH exhibited demographic, clinical and immunological characteristics that are significantly different compared with women born in the US or US territory. After adjusting for these characteristics, the FB WLWH had a significantly lower hazard of non-AIDS but not AIDS mortality compared to women born in the US or a US territory. These findings of non-increased mortality can help inform models of care to optimize treatment outcomes among FBWLWH in the United States.

Weight gain among treatment-naïve persons with HIV starting integrase inhibitors compared to non-nucleoside reverse transcriptase inhibitors or protease inhibitors in a large observational cohort in the United States and Canada

INTRODUCTION

Weight gain following antiretroviral therapy (ART) initiation is common, potentially predisposing some persons with HIV (PWH) to cardio-metabolic disease. We assessed relationships between ART drug class and weight change among treatment-naïve PWH initiating ART in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD).

METHODS

Adult, treatment-naïve PWH in NA-ACCORD initiating integrase strand transfer inhibitor (INSTI), protease inhibitor (PI) or non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based ART on/after 1 January 2007 were followed through 31 December 2016. Multivariate linear mixed effects models estimated weight up to five years after ART initiation, adjusting for age, sex, race, cohort site, HIV acquisition mode, treatment year, and baseline weight, plasma HIV-1 RNA level and CD4+ cell count. Due to shorter follow-up for PWH receiving newer INSTI drugs, weights for specific INSTIs were estimated at two years. Secondary analyses using logistic regression and all covariates from primary analyses assessed factors associated with >10% weight gain at two and five years.

RESULTS

Among 22,972 participants, 87% were male, and 41% were white. 49% started NNRTI-, 31% started PI- and 20% started INSTI-based regimens (1624 raltegravir (RAL), 2085 elvitegravir (EVG) and 929 dolutegravir (DTG)). PWH starting INSTI-based regimens had mean estimated five-year weight change of +5.9kg, compared to +3.7kg for NNRTI and +5.5kg for PI. Among PWH starting INSTI drugs, mean estimated two-year weight change was +7.2kg for DTG, +5.8kg for RAL and +4.1kg for EVG. Women, persons with lower baseline CD4+ cell counts, and those initiating INSTI-based regimens had higher odds of >10% body weight increase at two years (adjusted odds ratio = 1.37, 95% confidence interval: 1.20 to 1.56 vs. NNRTI).

CONCLUSIONS

PWH initiating INSTI-based regimens gained, on average, more weight compared to NNRTI-based regimens. This phenomenon may reflect heterogeneous effects of ART agents on body weight regulation that require further exploration.

Self-reported rates of impulsivity in Parkinson's Disease

OBJECTIVE

Impulsive decision-making is characterized by actions taken without considering consequences. Patients with Parkinson's disease (PD) who receive dopaminergic treatment, especially dopamine agonists, are at risk of developing impulsive-compulsive behaviors (ICBs). We assessed impulse-related changes across a large heterogeneous PD population using the Barratt impulsivity scale (BIS-11) by evaluating BIS-11 first- and second-order factors.

METHODS

We assessed a total of 204 subjects: 93 healthy controls (HCs), and 68 ICB- and 43 ICB + PD patients who completed the BIS-11. Using a general linear model and a least absolute shrinkage and selection operation regression, we compared BIS-11 scores between the HC, ICB- PD, and ICB + PD groups.

RESULTS

Patients with PD rated themselves as more impulsive than HCs in the BIS-11 total score, second-order attention domain, and first-order attention and self-control domains. ICB + patients recorded higher total scores as well as higher scores in the second-order non-planning domain and in self-control and cognitive complexity than ICB- patients.

INTERPRETATION

These results indicate that the patients with PD show particular problems with attentional control, whereas ICB + patients show a distinct problem in cognitive control and complexity. Additionally, it appears that all patients with PD are more impulsive than their age- and sex-matched healthy peers. Increased impulsivity may be a result of the disease course, or attributed to dopaminergic medication use, but these results emphasize the importance of the cognitive components of impulsivity in patients with PD.

Heavy cannabis use, dependence and the brain: a clinical perspective

AIMS

To summarize and evaluate our knowledge of the relationship between heavy cannabis use, cannabis use disorder (CUD) and the brain.

METHODS

Narrative review of relevant literature identified through existing systematic reviews, meta-analyses and a PubMed search. Epidemiology, clinical representations, potential causal mechanisms, assessments, treatment and prognosis are discussed.

RESULTS

Although causality is unclear, heavy and dependent cannabis use is consistently associated with a high prevalence of comorbid psychiatric disorders and learning and memory impairments that seem to recover after a period of abstinence. Evidence regarding other cognitive domains and neurological consequences, including cerebrovascular events, is limited and inconsistent. Abstinence after treatment is only achieved in a minority of cases; treatment targeted at reduction in use appears have some success. Potential moderators of the impact of CUD on the brain include age of onset, heaviness of use, CUD severity, the ratio of ∆9-tetrahydrocannabinol to cannabidiol and severity of comorbid disorders.

CONCLUSIONS

Current evidence of long-term effects of daily cannabis use and cannabis use disorder on brain-related outcomes is suggestive rather than conclusive, but use is associated with psychiatric morbidity and with cognitive impairments that recover after a period of abstinence.

Characterizing the double-sided cascade of care for adolescents living with HIV transitioning to adulthood across Southern Africa

INTRODUCTION

As adolescents and young people living with HIV (AYLH) age, they face a "transition cascade," a series of steps associated with transitions in their care as they become responsible for their own healthcare. In high-income countries, this usually includes transfer from predominantly paediatric/adolescent to adult clinics. In sub-Saharan Africa, paediatric HIV care is mostly provided in decentralized, non-specialist primary care clinics, where "transition" may not necessarily include transfer of care but entails becoming more autonomous for one's HIV care. Using different age thresholds as proxies for when "transition" to autonomy might occur, we evaluated pre- and post-transition outcomes among AYLH.

METHODS

We included AYLH aged <16 years at enrolment, receiving antiretroviral therapy (ART) within International epidemiology Databases to Evaluate AIDS Southern Africa (IeDEA-SA) sites (2004 to 2017) with no history of transferring care. Using the ages of 16, 18, 20 and 22 years as proxies for "transition to autonomy," we compared the outcomes: no gap in care (≥2 clinic visits) and viral suppression (HIV-RNA <400 copies/mL) in the 12 months before and after each age threshold. Using log-binomial regression, we examined factors associated with no gap in care (retention) in the 12 months post-transition.

RESULTS

A total of 5516 AYLH from 16 sites were included at "transition" age 16 (transition-16y), 3864 at 18 (transition-18y), 1463 at 20 (transition-20y) and 440 at 22 years (transition-22y). At transition-18y, in the 12 months pre- and post-transition, 83% versus 74% of AYLH had no gap in care (difference 9.3 (95% confidence interval (CI) 7.8 to 10.9)); while 65% versus 62% were virally suppressed (difference 2.7 (-1.0 to 6.5%)). The strongest predictor of being retained post-transition was having no gap in the preceding year, across all transition age thresholds (transition-16y: adjusted risk ratio (aRR) 1.72; 95% CI (1.60 to 1.86); transition-18y: aRR 1.76 (1.61 to 1.92); transition-20y: aRR 1.75 (1.53 to 2.01); transition-22y: aRR 1.47; (1.21 to 1.78)).

CONCLUSIONS

AYLH with gaps in care need targeted support to prevent non-retention as they take on greater responsibility for their healthcare. Interventions to increase virologic suppression rates are necessary for all AYLH ageing to adulthood.

Cognitive testing of an instrument to evaluate acceptability and use of pre-exposure prophylaxis products among women

Given the range of pre-exposure prophylaxis (PrEP) products currently being tested to prevent HIV in women, a standardized Acceptability and Use of PrEP Products Among Women Tool may facilitate comparisons of product acceptability and use across different geographies, trials, and users. We conducted three rounds of cognitive interviewing over 2 months in 2016, with 28 South African women who had experience participating in a range of PrEP product trials. The final instrument contained 41 items, including five new items that improved construct validity and 22 items modified for clarity. Changes were made due to unclear wording, difficulty answering, participant embarrassment, low response variability, and administrative formatting. Cognitive interviewing provided a means to address issues that would have inhibited this tool's ability to accurately collect data otherwise. This rapid, low-cost study provided valuable insight into participants' understanding of questions and demonstrated the utility of cognitive interviewing in international clinical trials.

Δ8 -Tetrahydrocannabivarin has potent anti-nicotine effects in several rodent models of nicotine dependence

BACKGROUND AND PURPOSE

Both types of cannabinoid receptors-CB1 and CB2 -regulate brain functions relating to addictive drug-induced reward and relapse. CB1 receptor antagonists and CB2 receptor agonists have anti-addiction efficacy, in animal models, against a broad range of addictive drugs. Δ9 -Tetrahydrocannabivarin (Δ9 -THCV)-a cannabis constituent-acts as a CB1 antagonist and a CB2 agonist. Δ8 -Tetrahydrocannabivarin (Δ8 -THCV) is a Δ9 -THCV analogue with similar combined CB1 antagonist/CB2 agonist properties.

EXPERIMENTAL APPROACH

We tested Δ8 -THCV in seven different rodent models relevant to nicotine dependence-nicotine self-administration, cue-triggered nicotine-seeking behaviour following forced abstinence, nicotine-triggered reinstatement of nicotine-seeking behaviour, acquisition of nicotine-induced conditioned place preference, anxiety-like behaviour induced by nicotine withdrawal, somatic withdrawal signs induced by nicotine withdrawal, and hyperalgesia induced by nicotine withdrawal.

KEY RESULTS

Δ8 -THCV significantly attenuated intravenous nicotine self-administration and both cue-induced and nicotine-induced relapse to nicotine-seeking behaviour in rats. Δ8 -THCV also significantly attenuated nicotine-induced conditioned place preference and nicotine withdrawal in mice.

CONCLUSIONS AND IMPLICATIONS

We conclude that Δ8 -THCV may have therapeutic potential for the treatment of nicotine dependence. We also suggest that tetrahydrocannabivarins should be tested for possible anti-addiction efficacy in a broader range of preclinical animal models, against other addictive drugs, and eventually in humans.

Development of parallel measures to assess HIV stigma and discrimination among people living with HIV, community members and health workers in the HPTN 071 (PopART) trial in Zambia and South Africa

INTRODUCTION

Integrating standardized measures of HIV stigma and discrimination into research studies of emerging HIV prevention approaches could enhance uptake and retention of these approaches, and care and treatment for people living with HIV (PLHIV), by informing stigma mitigation strategies. We sought to develop a succinct set of measures to capture key domains of stigma for use in research on HIV prevention technologies.

METHODS

From 2013 to 2015, we collected baseline data on HIV stigma from three populations (PLHIV (N = 4053), community members (N = 5782) and health workers (N = 1560)) in 21 study communities in South Africa and Zambia participating in the HPTN 071 (PopART) cluster-randomized trial. Forty questions were adapted from a harmonized set of measures developed in a consultative, global process. Informed by theory and factor analysis, we developed seven scales, with values ranging from 0 to 3, based on a 4-point agreement Likert, and calculated means to assess different aspects of stigma. Higher means reflected more stigma. We developed two measures capturing percentages of PLHIV who reported experiencing any stigma in communities or healthcare settings in the past 12 months. We validated our measures by examining reliability using Cronbach's alpha and comparing the distribution of responses across characteristics previously associated with HIV stigma.

RESULTS

Thirty-five questions ultimately contributed to seven scales and two experience measures. All scales demonstrated acceptable to very good internal consistency. Among PLHIV, a scale captured internalized stigma, and experience measures demonstrated that 22.0% of PLHIV experienced stigma in the community and 7.1% in healthcare settings. Three scales for community members assessed fear and judgement, perceived stigma in the community and perceived stigma in healthcare settings. Similarly, health worker scales assessed fear and judgement, perceived stigma in the community and perceived co-worker stigma in healthcare settings. A higher proportion of community members and health workers reported perceived stigma than the proportion of PLHIV who reported experiences of stigma.

CONCLUSIONS

We developed novel, valid measures that allowed for triangulation of HIV stigma across three populations in a large-scale study. Such comparisons will illuminate how stigma influences and is influenced by programmatic changes to HIV service delivery over time.

Randomized controlled trial of a positive affect intervention to reduce HIV viral load among sexual minority men who use methamphetamine

INTRODUCTION

In the era of HIV treatment as prevention (TasP), evidence-based interventions that optimize viral suppression among people who use stimulants such as methamphetamine are needed to improve health outcomes and reduce onward transmission risk. We tested the efficacy of positive affect intervention delivered during community-based contingency management (CM) for reducing viral load in sexual minority men living with HIV who use methamphetamine.

METHODS

Conducted in San Francisco, this Phase II randomized controlled trial tested the efficacy of a positive affect intervention for boosting and extending the effectiveness of community-based CM for stimulant abstinence to achieve more durable reductions in HIV viral load. From 2013 to 2017, 110 sexual minority men living with HIV who had biologically confirmed, recent methamphetamine use were randomized to receive a positive affect intervention (n = 55) or attention-control condition (n = 55). All individual positive affect intervention and attention-control sessions were delivered during three months of community-based CM where participants received financial incentives for stimulant abstinence. The 5-session positive affect intervention was designed to provide skills for managing stimulant withdrawal symptoms as well as sensitize individuals to natural sources of reward. The attention-control condition consisted of neutral writing exercises and self-report measures.

RESULTS

Men randomized to the positive affect intervention displayed significantly lower log10 HIV viral load at six, twelve and fifteen months compared to those in the attention-control condition. Men in the positive affect intervention also had significantly lower risk of at least one unsuppressed HIV RNA (≥200 copies/mL) over the 15-month follow-up. There were concurrent, statistically significant intervention-related increases in positive affect as well as decreases in the self-reported frequency of stimulant use at six and twelve months.

CONCLUSIONS

Delivering a positive affect intervention during community-based CM with sexual minority men who use methamphetamine achieved durable and clinically meaningful reductions in HIV viral load that were paralleled by increases in positive affect and decreases in stimulant use. Further clinical research is needed to determine the effectiveness of integrative, behavioural interventions for optimizing the clinical and public health benefits of TasP in sexual minority men who use stimulants such as methamphetamine.

Ethnicity, educational attainment, and physical health of older adults in the United States

OBJECTIVE

Minorities' diminished returns theory suggests that socioeconomic status (SES) resources generate fewer health benefits for racial and ethnic minority groups, compared to the majority group. The current study aimed to compare Hispanic and non-Hispanic white older adults for the association between educational attainment and poor physical self-rated health (SRH).

METHODS

The first wave of the University of Michigan National Poll on Healthy Aging (UM-NPHA) included 1820 older adults who were 50-80 years old and were either non-Hispanic white (n = 1618) or Hispanic white (n = 202). The main independent variable of interest was educational attainment. The main dependent variable of interest was poor physical SRH. Gender, age, marital status, and employment status were covariates. Ethnicity was the focal effect modifier.

RESULTS

Overall, higher level of educational attainment was associated with better physical SRH. A significant interaction was found between ethnicity and level of educational attainment, which was indicative of a smaller physical SRH gain due to high educational attainment for Hispanic white compared to non-Hispanic white older adults. In ethnic-specific models, we found evidence suggesting that high educational attainment reduced the odds of poor physical SRH for non-Hispanic whites but not for Hispanic whites.

CONCLUSION

Compared to non-Hispanic whites, Hispanic whites gain less physical SRH benefits from their educational attainment.

Sign-tracking is an expectancy-mediated behavior that relies on prediction error mechanisms

When discrete localizable stimuli are used during appetitive Pavlovian conditioning, "sign-tracking" and "goal-tracking" responses emerge. Sign-tracking is observed when conditioned responding is directed toward the CS, whereas goal-tracking manifests as responding directed to the site of expected reward delivery. These behaviors seem to rely on distinct, though overlapping neural circuitries, and, possibly, distinct psychological processes as well, and are thought to be related to addiction vulnerability. One currently popular view is that sign-tracking reflects an incentive motivational process, whereas goal-tracking reflects the influence of more top-down cognitive processes. To test these ideas, we used illness-induced outcome-devaluation and Kamin blocking procedures to determine whether these behaviors rely on similar or distinct underlying associative mechanisms. In Experiments 1 and 2 we showed that outcome-devaluation reduced sign-tracking responses, demonstrating that sign-tracking is controlled by reward expectancies. We also observed that post-CS goal-tracking in these animals is also devaluation sensitive. To test whether these two types of behaviors rely on similar or different prediction error mechanisms, we next tested whether Kamin blocking effects could be observed across these two classes of behaviors. In Experiment 3 we asked if sign-tracking to a lever CS could block the development of goal-tracking to a tone CS; whereas in Experiment 4, we examined whether goal-tracking to a tone CS could block sign-tracking to a lever CS. In both experiments blocking effects were observed suggesting that both sign- and goal-tracking emerge via a common prediction error mechanism. Collectively, the studies reported here suggest that the psychological mechanisms mediating sign- and goal-tracking are more similar than is commonly acknowledged.

Age of onset or age at assessment-that is the question: Estimating newly incident alcohol drinking and rapid transition to heavy drinking in the United States, 2002-2014

Age-specific incidence estimates are important and useful facts in psychiatric epidemiology, but incidence estimation can be challenging. Methods artifacts are possible. In the United States, where the minimum legal drinking age is 21 years, recent cross-sectional field research on 12- to 25-year-olds applied conventional "age-at-assessment" approaches (AAA) for incidence estimation based on 12-month recall. Estimates disclosed unexpected nonlinear patterns in age-specific incidence estimates for both drinking onset and for transitioning from first drink to heavy drinking. Here, our aim is to draw attention to an "age of onset" (AOO) alternative to AAA approaches and to verify whether the AOO approach also discloses nonlinearity. Yearly data are from U.S. nationally representative samples drawn and assessed for National Surveys on Drug Use and Health, 2002-2014, with standardized audio computer-assisted self-interview assessments for drinking outcomes. Both AAA and AOO approaches show nonlinearities, with an unexpected dip in drinking incidence rates after age 18 and before the age 21 minimum legal drinking age. The AOO and the AAA approaches disclosed similar age-specific patterns. We discuss advantages of the AOO approach when nonlinear incidence patterns can be anticipated, but we conclude that the AAA approach has not created an artifactual nonlinear pattern.

Towards a unified analysis of brain maturation and aging across the entire lifespan: A MRI analysis

There is no consensus in literature about lifespan brain maturation and senescence, mainly because previous lifespan studies have been performed on restricted age periods and/or with a limited number of scans, making results instable and their comparison very difficult. Moreover, the use of nonharmonized tools and different volumetric measurements lead to a great discrepancy in reported results. Thanks to the new paradigm of BigData sharing in neuroimaging and the last advances in image processing enabling to process baby as well as elderly scans with the same tool, new insights on brain maturation and aging can be obtained. This study presents brain volume trajectory over the entire lifespan using the largest age range to date (from few months of life to elderly) and one of the largest number of subjects (N = 2,944). First, we found that white matter trajectory based on absolute and normalized volumes follows an inverted U-shape with a maturation peak around middle life. Second, we found that from 1 to 8-10 y there is an absolute gray matter (GM) increase related to body growth followed by a GM decrease. However, when normalized volumes were considered, GM continuously decreases all along the life. Finally, we found that this observation holds for almost all the considered subcortical structures except for amygdala which is rather stable and hippocampus which exhibits an inverted U-shape with a longer maturation period. By revealing the entire brain trajectory picture, a consensus can be drawn since most of the previously discussed discrepancies can be explained. Hum Brain Mapp 38:5501-5518, 2017. © 2017 Wiley Periodicals, Inc.

Mothers with substance addictions show reduced reward responses when viewing their own infant's face

Maternal addiction constitutes a major public health problem affecting children, with high rates of abuse, neglect, and foster care placement. However, little is known about the ways in which substance addiction alters brain function related to maternal behavior. Prior studies have shown that infant face cues activate similar dopamine-associated brain reward regions to substances of abuse. Here, we report on a functional MRI study documenting that mothers with addictions demonstrate reduced activation of reward regions when shown reward-related cues of their own infants. Thirty-six mothers receiving inpatient treatment for substance addiction were scanned at 6 months postpartum, while viewing happy and sad face images of their own infant compared to those of a matched unknown infant. When viewing happy face images of their own infant, mothers with addictions showed a striking pattern of decreased activation in dopamine- and oxytocin-innervated brain regions, including the hypothalamus, ventral striatum, and ventromedial prefrontal cortex-regions in which increased activation has previously been observed in mothers without addictions. Our results are the first to demonstrate that mothers with addictions show reduced activation in key reward regions of the brain in response to their own infant's face cues. Hum Brain Mapp 38:5421-5439, 2017. © 2017 Wiley Periodicals, Inc.

Effects of drugs of abuse on hippocampal plasticity and hippocampus-dependent learning and memory: contributions to development and maintenance of addiction

It has long been hypothesized that conditioning mechanisms play major roles in addiction. Specifically, the associations between rewarding properties of drugs of abuse and the drug context can contribute to future use and facilitate the transition from initial drug use into drug dependency. On the other hand, the self-medication hypothesis of drug abuse suggests that negative consequences of drug withdrawal result in relapse to drug use as an attempt to alleviate the negative symptoms. In this review, we explored these hypotheses and the involvement of the hippocampus in the development and maintenance of addiction to widely abused drugs such as cocaine, amphetamine, nicotine, alcohol, opiates, and cannabis. Studies suggest that initial exposure to stimulants (i.e., cocaine, nicotine, and amphetamine) and alcohol may enhance hippocampal function and, therefore, the formation of augmented drug-context associations that contribute to the development of addiction. In line with the self-medication hypothesis, withdrawal from stimulants, ethanol, and cannabis results in hippocampus-dependent learning and memory deficits, which suggest that an attempt to alleviate these deficits may contribute to relapse to drug use and maintenance of addiction. Interestingly, opiate withdrawal leads to enhancement of hippocampus-dependent learning and memory. Given that a conditioned aversion to drug context develops during opiate withdrawal, the cognitive enhancement in this case may result in the formation of an augmented association between withdrawal-induced aversion and withdrawal context. Therefore, individuals with opiate addiction may return to opiate use to avoid aversive symptoms triggered by the withdrawal context. Overall, the systematic examination of the role of the hippocampus in drug addiction may help to formulate a better understanding of addiction and underlying neural substrates.