Resting-state fMRI has become a popular tool to study how distant brain areas are functionally connected

Utilizing data from the IMAGEN study that included longitudinal fMRI and measures of PS at follow-up, Papanstasiou et al. observed increases in right frontal activation during reward anticipation and feedback of win from age 14 to 19 that was associated with PS at age 19; this increase over time was not observed in youth who did not report PS. The authors speculate whether this finding could be a possible compensatory mechanism. However, given that PS were not assessed at age 14, results are to be interpreted with caution. Unlike task-based fMRI, it is less susceptible to performance and vigilance differences between groups, which facilitates interpretation of group differences. Again, the PNC has allowed large-scale investigation of functional connectivity across development. With regard to static functional connectivity , Satterthwaite et al. showed that PS youth exhibited similar patterns of dysconnectivity to patients with overt psychosis. In particular, they observed hyperconnectivity within the default-mode network and reduced functional connectivity within the executive control network . However, in one of the largest pediatric population-based samples Karcher et al. recently reported hypoconnectivity within the DMN and within the executive control networks that is associated with increased PS in 9- to 11-year old children . These differences in observed hypo- vs. hyperconnectivity may be attributable to age differences between the two studies. Nevertheless, there has been a similar dissonance in adult cohorts with overt psychosis, where both hypo- and hyperconnectivity of the DMN and executive control networks has been described . In an elegant follow-up study that applied multivariate sparse canonical correlation analysis to the PNC resting state data, Xia and colleagues corroborated that in fact the segregation between the DMN and executive control networks is a common feature across multiple psychopathology dimensions, but the psychosis dimension shows the strongest effect .

Moreover, a recent study of this cohort that investigated dynamic properties of functional connectivity, i.e., time-varying patterns of whole-brain connectivity,vertical grow system found that previously described dysconnectivity between the DMN and executive control networks in youth experiencing PS is time-dependent, and only occurs during certain periods of a resting-state scan, whereas dysconnectivity in visual and sensorimotor areas is much more pervasive . The Human Connectome Project is an adult cohort in which resting-state fMRI as well as self-reported PS were acquired. Here, PS were significantly inversely correlated with cognitive abilities, an effect that was partially mediated by global efficiency of the executive control network, a measure of network integration . With regard to dynamic functional connectivity in the HCP, it has recently been shown that adults experiencing PS spend more time in a dynamic state, i.e., a distinct time-varying connectivity pattern, characterized by reduced connectivity within the DMN ; a finding that mirrors previous results in studies on individuals with overt psychosis . Even though pediatric population neuroscience is still in its infancy, studies overwhelmingly find that PS in childhood and adolescence pose a risk factor for later development of overt psychiatric illness, and are overall associated with reduced functioning and quality of life. Many early intervention specialty programs offer a coherent multi-modal treatment framework for clients, including psychopharmacological treatment, psychotherapy and psychoeducation as well as vocational counseling. Meta-analytic results suggest that multidisciplinary therapies can delay or prevent transition to overt psychosis . Low risk psychosocial interventions targeting functioning have been shown to be effective in CHR youth; such approaches are likely to be also effective in a broader audience .

These results find consideration in the recently published guidelines of the European Psychiatric Association where a dual treatment consisting of cognitive behavioral therapy and pharmacological treatment yields recommendation grade A for adult CHR individuals. For children and adolescents experiencing PS, as targeted by pediatric population neuroscience, the expert recommendation is specific psychological interventions to improve functioning and close monitoring of PS. PS are often preceded by non-specific behavioral and emotional problems in childhood related to increased adversity and trauma. Since these precursors in themselves pose a risk for development of diverse psychopathologies, we argue – as others before us – that these childhood-onset problems offer another promising target for population-based preventive interventions. However, causal mechanisms from abnormal neurodevelopment to subsequent psychopathology are not yet understood and require further longitudinal research. Since only a minority of individuals with PS access appropriate mental health services, it will be important to implement services appropriate to a broad audience, for example in schools. It will be essential to identify those individuals at highest risk, and to reduce the number of false positives in order to provide cost effective services and to reduce stigma. Individual risk calculators developed and tested in CHR cohorts may not work as well when broadening the target audience. With sufficient longitudinal data, questionnaires such as the Psychosis Questionnaire, Brief Version may be amenable for community samples, and may be used to develop risk calculators for youth in the general population. Given the evidence presented here and results from the Outreach and Support in South London and Headspace initiatives , we argue that findings from population-based studies are adequate for guiding policy-making toward further emphasis on public health efforts, although more systematic research is needed in this area.

Destigmatization initiatives for mental illness have been shown to be effective in reducing discrimination and stigma , and broadly accessible mental health programs like Headspace and Jigsaw are promising to make a difference in the field of adolescent mental health . However, the specific efficacy of these programs warrants further study, and caution is advised to not over-pathologize potentially transient occurrence of mental health problems.The prevalence of alcohol, tobacco, and other substance use is higher among gay, bisexual, and other men who have sex with men than in the overall population . Although Hughes and Eliason noted that substance and alcohol use have declined in lesbian, gay, bisexual, and transgender populations, the prevalence of heavy alcohol and substance use remains high among younger lesbians and gay men, and in some cases older lesbians and gay men. Marginalization on the basis of sexual orientation increases the risk for problematic substance use. For example, GBM men were approximately one and half times more likely to have reported being diagnosed with a substance use disorder during their lifetime than heterosexual men , and one and a half times more likely to have been dependent on alcohol or other substances in the past year . GBM also have higher rates of mental health issues than their heterosexual counterparts . In a review of 10 studies, Meyer found that gay men were twice as likely to have experienced a mental disorder during their lives as heterosexual men. More specifically, gay men were approximately two and a half times more likely to have reported a mood disorder or an anxiety disorder than heterosexual men. A review by King and colleagues found that lesbian, gay, and bisexual individuals were more than twice as likely as heterosexuals to attempt suicide over their lifetime and one and a half times more likely to experience depression and anxiety disorders in the past year,vertical grow rack as well as over their lifetime.Few Canadian studies have explored population-based estimates for mental health outcomes among GBM. In one cross-sectional study of Canadian gay/“homosexual” and bisexual men using 2003 Canadian Community Health Survey data, Brennan and colleagues found participants were nearly three times as likely to report a mood or anxiety disorder than heterosexual men. Pakula & Shoveller conducted a more recent cross-sectional analysis that used 2007–2008 Canadian Community Health Survey data and found again that GBM were 3.5 times more likely to report a mood disorder compared with heterosexual males. These analyses used government-run population-based study data, which may limit self-disclosure of sexual minority status, and further relied on a single identity variable to measure sexual orientation, which ignores same-sex sexual behaviors. There is an inextricable yet varied relationship between an individual’s mental health and substance use. Substance use may lead to poorer mental health or, inversely, poor mental health may lead to increased substance use . A variety of substances have been shown to be associated with negative mental health events or symptoms. For example, Clatts, Goldsamt, and Li found that a third of young MSM who used club drugs on a regular basis reported having attempted suicide, and almost half of those who had attempted suicide, did so multiple times over their lifetime. They also found that more than half of regular club drugs users had high levels of depressive symptoms. McKirnan and colleagues found that GBM who showed signs of depression were nearly twice as likely to smoke. Stall and colleagues identified a “dose-response” relationship between self-rated mental well being and alcohol related problems: GBM who self-rated their mental well-being as low were approximately three times more likely to have alcohol related problems and those who rated it as moderate were nearly twice as likely to have alcohol related problems. Respondents who scored as depressed were also one and half times more likely to report using multiple drugs and nearly twice as likely to report weekly drug use.

Syndemics [clusters of mutually reinforcing epidemics that interact with one another to make overall burden of disease within a population worse ] has been used in research with GBM to explain how various psychosocial variables such as poly drug use, mental health conditions, and intimate partner violence increase the likelihood of acquiring HIV . However, nearly all of these studies have relied on convenience samples through online and venue-based recruitment; thus, they may not be representative of the larger underlying population of GBM. In order to address issues of representativeness and limitations of non-probability sampling in past research with GBM, we used respondent-driven sampling to estimate population parameters that are more representative than convenience samples . RDS is a type of chain-referral research technique in which participants are asked to recruit individuals from within their social networks in successive waves, and estimates population parameters using measures of network size and recruitment homophily. By utilizing RDS we sought to produce a more representative sample of the GBM population in Metro Vancouver in order to determine the prevalence of mental health issues and substance use as well as the association between these factors.We analyzed cross-sectional data from participants enrolled in the Momentum Health Study, a longitudinal bio-behavioral prospective cohort study of HIV-positive and HIV-negative GBM in Metro Vancouver, Canada. The overall aim of this study was to examine the impact of a biomedical intervention—increased access to highly active antiretroviral therapy for HIV— on HIV risk behaviors among GBM. The present analysis utilized data collected from participants’ first study visit that occurred between February 2012 and February 2014. We used RDS to recruit GBM in the Greater Vancouver area . Initial seeds were selected in person through partnerships with community agencies or online through advertisements on GBM socio-sexual networking mobile apps or websites . These seeds were then provided with up to six vouchers to recruit other GBM they knew. All participants were screened for eligibility and provided written informed consent at the in-person study office in downtown Vancouver. A computer-assisted, self-administrated questionnaire was used to collect socio-demographic, psychosocial, and behavioral variables. Subsequently, a nurse-administered structured interview collected information on history of mental health and substance dependence diagnosis and treatment, and participants provided blood samples to test for HIV and other sexually transmitted infections . Participants received a $50 honorarium for completing the study protocol and an additional $10 for each eligible GBM they recruited into the study. All project investigators’ institutional Research Ethics Boards granted ethical approval. Moore and colleagues have published additional detail on the Momentum Health Study protocol.Independent variables included socio-demographics, sexual behaviors, substance use behaviors, Alcohol Use Disorders Identification Test categorical scores , and the Hospital Anxiety and Depression Scale categorical scores of anxious and depressive symptoms . Socio-demographic characteristics include: age, sexual identity , ethnicity , immigration status , residence , highest formal education attained, current student status, annual income, being out as gay, HIV serostatus, and current regular partnership status. Sexual behaviors included engaged in sex work in the past 6 months and number of male anal sex partners in the past 6 months. Participants reported whether they had used a variety of substances in the past six months: cigarettes, cannabis, erectile dysfunction drugs, poppers , steroids , cocaine, ecstasy, ketamine, gamma-hydroxybutyrate , hallucinogens , crystal methamphetamine , crack, other stimulants , heroin, morphine, other opioids , benzodiazepines, and other prescription drugs .

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