An Implementation Approach to Translating Assessment Data into Treatment for Disorders of Addiction.

Effective translation of data to inform real-time patient care is lacking in addiction inpatient settings. The current study presents the optimization of an assessment report that is used by clinicians to individualize treatment. A multi-aim, iterative approach was taken, utilizing an implementation science perspective to arrive at a final version of the assessment report. This occurred at a small inpatient addiction treatment facility. Participants were all available clinical staff (N = 7; female = 71%). A quantitative survey was used for aims 1 and 2 to, respectively, assess motives and context around the report as well as evaluate its design. Aim 3 focused on optimization via semi-structured interviews. Descriptive and modified content analyses were utilized appropriately across aims. This resulted in five versions of the assessment report being created between February 2021 and August 2022, the most recent of which was adapted into patients' electronic medical records. We discuss each version of the report in depth, including clinicians' iterative feedback and researchers' perceived barriers to this translational process. The response rate was 64.3%. The current study highlights a replicable approach for optimizing the translation of assessment data into treatment for patients with disorders of addiction as well as an assessment report that could be utilized by similar facilities with a naturally low sample size.

Adapting, Implementing, and Maintaining a Group Cognitive Behavioral Therapy Program at an Inpatient Addiction Treatment Facility.

Background: Quality training is an oft-cited barrier to effective implementation and ongoing delivery of high-quality evidence-based practice (EBP) across fields. This is especially true in the addiction field, but there is little cited evidence for optimal methods to improve EBP in inpatient addiction facilities with minimal resources. Objective: The current paper focuses on evaluating the state of our facility's group CBT manual and clinical training on the manual in a "realistic" (ie, non-RCT, non-grant-funded) inpatient addiction treatment setting. Methods: Five full-time clinicians volunteered to take part in the study (woman = 60%; Mage = 36.20 years). The study involved a mix of semi-structured interviews and surveys designed to measure seven outcomes (barriers, feasibility, useability, appropriateness, acceptability, burden, trialability). Results: Three themes emerged from the data that impacted the group CBT manual: training, timing, and functionality. Addressing these themes allowed for a new, optimal manual and training procedure to be put into place. Conclusion: The current study highlights that under-resourced inpatient addiction facilities can still methodically utilize implementation approaches to study their EBP, namely CBT. Such an approach will ensure that the highest quality care is being delivered to patients and actively addresses known training barriers that prevent proper EBP delivery.

Deriving a Measure of Social Recovery Capital From the Important People and Activities Instrument: Construction and Psychometric Properties.

AIM: This study presents a measure of Social Recovery Capital (SRC) derived from the Important People and Activities instrument (IPA). METHODS: The sample comprised young adults who participated in the Collaborative Study on the Genetics of Alcoholism, a high-risk family study of alcohol use disorder (N = 2472). Exploratory and confirmatory factor analysis identified influential items and factor structure, adjusting for family relatedness. The final scale was tested for reliability and validity. RESULTS: Factor analysis retained 10 items loading on three factors (Network Abstinence Behaviors, Basic Network Structure and Network Importance) that together explained 42% of the variance in SRC. The total model showed adequate fit (Comparative Fit Index = 0.95; Tucker Lewis Index = 0.93; Root Mean Square Error of Approximation = 0.06; Standardized Root Mean Squared Residual = 0.05) and acceptable reliability (α = 0.60; McDonald's ω = 0.73) and correlated with validation measures mostly in the weak to moderate range. Due to variable factor scores for reliability and validity, we only recommend using the total score. CONCLUSION: The SRC-IPA is a novel measure of SRC derived from the IPA that captures social network data and has applications in research and clinical work. Secondary data analyses using the SRC-IPA in studies that collected the IPA can further demonstrate the interaction of SRC with a wide variety of clinical indicators and demographic characteristics, making it a valuable addition to other measures of SRC.

The effect of cannabis policies on treatment outcomes for cannabis use among U.S. adults.

BACKGROUND: Research has explored the impact of various medical cannabis policies on substance use treatment admission in recent years, but we know little about factors related to participants' treatment engagement and outcome. To fill this gap in the existing literature, this study used national data to examine the influence of cannabis policies (decriminalized, medical, and recreational) and referral sources (criminal justice vs. voluntary) on treatment completion and length of stay. METHODS: Data came from the Treatment Episode Data Set-Discharge (2006-2017) on adults 18+ whose primary drug at treatment admission was cannabis. Difference-in-difference analyses using logistic regression examined the effect of cannabis policies on outpatient treatment completion (yes/no; n = 2,192,807) and length of stay (more/fewer than 90 days; n = 1,863,585) in those with a criminal justice or voluntary referral source. RESULTS: Cannabis policy was not associated with treatment completion in either those with a criminal justice or voluntary referral source. Compared to individuals in states where cannabis use was strictly illegal, those in states with a decriminalization policy were less likely to stay in treatment for 91+ days regardless of the referral source. CONCLUSIONS: Cannabis policy appears to have a differential effect on treatment completion versus length of stay, with policy having no impact on successful treatment completion. Specifically, we found that decriminalization policies hinder treatment engagement past 90 days. In this sense, length of stay may be a more useful measure of treatment outcome for research than treatment completion moving forward. Furthermore, our study found that neither medical nor recreational policies affected length of stay or treatment completion, regardless of referral source.

In-vivo design feedback and perceived utility of a genetically-informed smoking risk tool among current smokers in the community.

BACKGROUND: The use of genetically-informed personalized risk information for behavioral disorders, namely smoking and smoking-related behaviors, is a promising yet understudied area. The Genetics and Smoking Risk Profile, or RiskProfile, leverages genetic and environmental information to communicate one's risk for smoking-related diseases. Although prior studies have examined attitudes toward genetic results, little research has investigated these perceptions through a lens of in-vivo testing; that is, user-centered design feedback in response to personalized genetic results being returned contemporaneously. This qualitative study engaged current smokers in usability testing of the RiskProfile within the context of concurrently receiving this personalized, genetically-informed smoking cessation intervention. METHODS: Eighty-nine participants who were current smokers responded to open-ended interview questions on perceptions of smoking-related genetic information and the content and format of the RiskProfile intervention that they had received moments before. Data were analyzed via the conventional content analysis approach in which themes were allowed to emerge throughout the analysis. RESULTS: Participants were able to reference and offer design input on specific elements of the RiskProfile. Overall, current smokers perceived the RiskProfile to have high potential utility. Constructive feedback that current smokers offered about the tool centered around suggested improvements to optimize its usability and technical content. CONCLUSIONS: The detailed and constructive feedback from participants highlights that in-vivo feedback offers a useful design approach that addresses concerns of rigor and relevance when returning genetic results. This unique method demonstrated perceived utility and constructive design feedback for the RiskProfile among current smokers and can play an important role in optimizing the design and implementation of personalized genetic risk interventions moving forward.

Predicting alcohol use disorder remission: a longitudinal multimodal multi-featured machine learning approach.

Predictive models for recovering from alcohol use disorder (AUD) and identifying related predisposition biomarkers can have a tremendous impact on addiction treatment outcomes and cost reduction. Our sample (N = 1376) included individuals of European (EA) and African (AA) ancestry from the Collaborative Study on the Genetics of Alcoholism (COGA) who were initially assessed as having AUD (DSM-5) and reassessed years later as either having AUD or in remission. To predict this difference in AUD recovery status, we analyzed the initial data using multimodal, multi-features machine learning applications including EEG source-level functional brain connectivity, Polygenic Risk Scores (PRS), medications, and demographic information. Sex and ancestry age-matched stratified analyses were performed with supervised linear Support Vector Machine application and were calculated twice, once when the ancestry was defined by self-report and once defined by genetic data. Multifeatured prediction models achieved higher accuracy scores than models based on a single domain and higher scores in male models when the ancestry was based on genetic data. The AA male group model with PRS, EEG functional connectivity, marital and employment status features achieved the highest accuracy of 86.04%. Several discriminative features were identified, including collections of PRS related to neuroticism, depression, aggression, years of education, and alcohol consumption phenotypes. Other discriminated features included being married, employed, medication, lower default mode network and fusiform connectivity, and higher insula connectivity. Results highlight the importance of increasing genetic homogeneity of analyzed groups, identifying sex, and ancestry-specific features to increase prediction scores revealing biomarkers related to AUD remission.

Assessing Stakeholder Perceptions of the Utility of Genetic Information for the Clinical Care of Mental Health Disorders: We Have a Will but Need to See the Way.

Academic stakeholders' (primarily mental health researchers and clinicians) practices and attitudes related to the translation of genetic information into mental health care were assessed. A three-part survey was administered at two large, urban universities. Response frequencies were calculated. Participants (N = 64) reported moderate levels of translational practice, adequate levels of genetic knowledge, and variable levels of genetic competence. They held positive attitudes toward translating genetic information about mental health broadly but negative attitudes about the impact that such information would have on specific aspects of care. The current study lays the groundwork for further inquiry into translating genetic information to mental health care.

Trends in mental health service utilization among LGB+ college students.

OBJECTIVES: 1) Compare service utilization among LGB+ and straight-identified students. 2) Assess rates of mental health concerns among LGB+ students only. Participants: Undergraduates (N = 675) reported on their sexual orientation, mental health conditions, and past service providers. Methods: Logistic regression was used for aim 1 and descriptive statistics for aim 2. Results: LGB+ students were more likely than straight-identified students to seek services for anxiety (odds ratio [OR] = 2.051; p < .01) or depression (OR = 3.058; p < .001) and from a counselor/therapist/psychologist (OR = 2.937; p < .001) or their university's counseling/health services (OR = 1.933; p < .01). Bisexual students utilized the most services. Conclusions: Colleges must ensure that programing, outreach, and overall support for the mental health needs of their LGB+ students are being met so that this vulnerable population continues to seek services.

Developing community-based health education strategies with family history: Assessing the association between community resident family history and interest in health education.

BACKGROUND: Family history (FH) is an underutilized genetically informative tool that can influence disease prevention and treatment. It is unclear how FH fits into the development of community-based health education. This study examines the role that FH plays in perceived threat and health education related to mental and chronic physical conditions in the context of the health belief model. METHODS: Data were collected from 1,048 adult participants aged 18-90 years. Approximately 76% of participants indicated African-American race/ethnicity and 35% had less than high school level education. Self-report data were collected on FH of four disorders: anxiety, depression, diabetes, and high blood pressure. Interest in receiving information regarding prevention as well as future testing efforts was assessed broadly. A series of logistic regressions examined the association between FH for each of the disorders and interest in receiving information on (1) prevention of diseases in general and (2) testing for diseases in general. These associations were also analyzed after accounting for the influence of perceived threat of conditions. RESULTS: Interest in receiving general health education was significantly associated with FH of depression (OR = 2.72, 95% CI = 1.74-4.25), anxiety (OR = 2.26, 95% CI = 1.45-3.22), and high blood pressure (OR = 2.54, 95% CI = 1.05-6.12). After adjustment for perceived threat, the magnitude of these associations was reduced substantially. The associations between perceived threat and either interest in receiving information on disease testing or receiving general health education were strong and significant across all conditions (OR = 2.11-3.74). DISCUSSION: These results provide evidence that perceived threat mediates the association between FH and engagement with health education. Currently available health education programs may benefit from considering the role of FH in an individual's motivation for participation in health education activities alongside other factors.

Proof of Concept of a Personalized Genetic Risk Tool to Promote Smoking Cessation: High Acceptability and Reduced Cigarette Smoking.

Relatively little is known about the possible effects of personalized genetic risk information on smoking, the leading preventable cause of morbidity and mortality. We examined the acceptability and potential behavior change associated with a personalized genetically informed risk tool (RiskProfile) among current smokers. Current smokers (n = 108) were enrolled in a pre-post study with three visits. At visit 1, participants completed a baseline assessment and genetic testing via 23andMe. Participants' raw genetic data (CHRNA5 variants) and smoking heaviness were used to create a tailored RiskProfile tool that communicated personalized risks of smoking-related diseases and evidence-based recommendations to promote cessation. Participants received their personalized RiskProfile intervention at visit 2, approximately 6 weeks later. Visit 3 involved a telephone-based follow-up assessment 30 days after intervention. Of enrolled participants, 83% were retained across the three visits. Immediately following intervention, acceptability of RiskProfile was high (M = 4.4; SD = 0.6 on scale of 1 to 5); at 30-day follow-up, 89% of participants demonstrated accurate recall of key intervention messages. In the full analysis set of this single-arm trial, cigarettes smoked per day decreased from intervention to 30-day follow-up [11.3 vs. 9.8; difference = 1.5; 95% confidence interval (0.6-2.4); P = 0.001]. A personalized genetically informed risk tool was found to be highly acceptable and associated with a reduction in smoking, although the absence of a control group must be addressed in future research. This study demonstrates proof of concept for translating key basic science findings into a genetically informed risk tool that was used to promote progress toward smoking cessation.Prevention Relevance: This study demonstrates that personal genetic information can be incorporated into a risk feedback tool that was highly acceptable to current smokers and associated with reductions in smoking. These findings may pave the way for effectiveness and implementation research on genetically-informed behavior change interventions to enhance cancer prevention efforts.

Prospective Predictors of Sexual Revictimization Among College Students.

This study examined the prevalence rates of sexual violence revictimization during each year of college. In addition, the impact of key mental health concerns on these rates was investigated. Incoming first-year students at a large, urban university completed a survey about their exposure to incidences of sexual assault before college and about their mental health symptoms. During each subsequent spring semester, experiences of sexual assault and mental health symptoms were reassessed. The sample was limited to individuals who reported sexual assault for at least one time period (N = 3,294). More than 60% of individuals who endorsed an initial incident of sexual assault reported no subsequent incidences, leading to an overall revictimization rate of 39.5%. Rates of revictimization were higher for those identifying as women, as compared to men, and those identifying as White, as compared to those identifying as Asian or "other." Trauma-related distress and increased symptoms of alcohol use disorder (AUD) and depression were all related to a greater risk of experiencing revictimization. Given that experiencing an initial sexual assault greatly increases the risk of experiencing revictimization, and considering the notable prevalence rates of sexual assault on college campuses, it is imperative to examine trends in revictimization throughout the course of college. Examining factors that increase risk for experiencing revictimization is crucial to developing university-wide effective prevention and intervention efforts. In addition to the efforts to increase the reporting of incidences of sexual assault, universal programming efforts should also focus on factors that promote resilience in the face of sexual assault, such as reducing risky drinking behavior, increasing social support, and reducing stigma around the reporting of mental health symptoms.

Four Actionable Bottlenecks and Potential Solutions to Translating Psychiatric Genetics Research: An Expert Review.

BACKGROUND: Psychiatric genetics has had limited success in translational efforts. A thorough understanding of the present state of translation in this field will be useful in the facilitation and assessment of future translational progress. PURPOSE: A narrative literature review was conducted. Combinations of 3 groups of terms were searched in EBSCOhost, Google Scholar, and PubMed. The review occurred in multiple steps, including abstract collection, inclusion/exclusion criteria review, coding, and analysis of included papers. RESULTS: One hundred and fourteen articles were analyzed for the narrative review. Across those, 4 bottlenecks were noted that, if addressed, may provide insights and help improve and increase translation in the field of psychiatric genetics. These 4 bottlenecks are emphasizing linear translational frameworks, relying on molecular genomic findings, prioritizing certain psychiatric disorders, and publishing more reviews than experiments. CONCLUSIONS: These entwined bottlenecks are examined with one another. Awareness of these bottlenecks can inform stakeholders who work to translate and/or utilize psychiatric genetic information. Potential solutions include utilizing nonlinear translational frameworks as well as a wider array of psychiatric genetic information (e.g., family history and gene-environment interplay) in this area of research, expanding which psychiatric disorders are considered for translation, and when possible, conducting original research. Researchers are urged to consider how their research is translational in the context of the frameworks, genetic information, and psychiatric disorders discussed in this review. At a broader level, these efforts should be supported with translational efforts in funding and policy shifts.

Genetic and environmental risk structure of internalizing psychopathology in youth.

BACKGROUND: Internalizing disorders (IDs), consisting of syndromes of anxiety and depression, are common, debilitating conditions often beginning early in life. Various trait-like psychological constructs are associated with IDs. Our prior analysis identified a tripartite model of Fear/Anxiety, Dysphoria, and Positive Affect among symptoms of anxiety and depression and the following constructs in youth: anxiety sensitivity, fearfulness, behavioral activation and inhibition, irritability, neuroticism, and extraversion. The current study sought to elucidate their overarching latent genetic and environmental risk structure. METHODS: The sample consisted of 768 juvenile twin subjects ages 9-14 assessed for the nine, abovementioned measures. We compared two multivariate twin models of this broad array of phenotypes. RESULTS: A hypothesis-driven, common pathway twin model reflecting the tripartite structure of the measures were fit to these data. However, an alternative independent pathway model provided both a better fit and more nuanced insights into their underlying genetic and environmental risk factors. CONCLUSIONS: Our findings suggest a complex latent genetic and environmental structure to ID phenotypes in youth. This structure, which incorporates both clinical symptoms and various psychological traits, informs future phenotypic approaches for identifying specific genetic and pathophysiological mechanisms underlying ID risk.

Participatory Design of a Personalized Genetic Risk Tool to Promote Behavioral Health.

Despite major advancements in genomic medicine, research to optimize the design and communication of genetically informed interventions in behavioral health has lagged. The goal of this study was to engage potential end users in participatory codesign of a personalized genetically informed risk tool to intervene on high-risk health behaviors. We used structured interviews to examine end-user attitudes and interest in personalized genetics, qualitative interviews to guide iterative design of a genetically informed tool, and questionnaires to assess acceptability and potential utility of the tool. Participants expressed strong demand for using personal genetics to inform smoking and alcohol-related disease risk and guide treatment (78%-95% agreed). Via iterative design feedback, we cocreated a genetically informed risk profile featuring (i) explanation of genetic and phenotypic markers used to construct a risk algorithm, (ii) personalized risks and benefits of healthy behavior change, and (iii) recommended actions with referral to freely available resources. Participants demonstrated sufficient understanding and cited motivating behavior change as the most useful purpose of the tool. In three phases, we confirmed strong desire for personalized genetics on high-risk health behaviors; codesigned a genetically informed profile with potential end users; and found high acceptability, comprehensibility, and perceived usefulness of the profile. As scientific discovery of genomic medicine advances in behavioral health, we must develop the tools to communicate these discoveries to consumers who stand to benefit. The potential of genomic medicine to engage populations and personalize behavioral health treatment depends, in part, on preparatory studies to design for the future implementation of genetically informed interventions.

Characterization of Service Use for Alcohol Problems Across Generations and Sex in Adults With Alcohol Use Disorder.

BACKGROUND: There are gaps in the literature on service use (help-seeking and treatment utilization) for alcohol problems among those with alcohol use disorder (AUD). First, policy changes and cultural shifts (e.g., insurance) related to AUD have occurred over the last few decades, making it important to study generational differences. Second, multiple studies have found that females receive fewer services than males, and exploring whether these sex differences persist across generations can inform public health and research endeavors. The current study examined service use for alcohol problems among individuals with AUD. The aims were as follows: (i) to describe service use for alcohol problems; (ii) to assess generational differences (silent [b. 1928 to 1945], boomer [b. 1946 to 1964], generation X [b. 1965 to 1980], millennial [b. 1981 to 1996]) in help-seeking and treatment utilization; and (iii) to examine sex differences across generations. METHODS: Data were from affected family members of probands who participated in the Collaborative Study on the Genetics of Alcoholism (N = 4,405). First, frequencies for service use variables were calculated across generations. Pearson chi-square and ANOVA were used to test for differences in rates and types of service use across generations, taking familial clustering into account. Next, Cox survival modeling was used to assess associations of generation and sex with time to first help-seeking and first treatment for AUD, and time from first onset of AUD to first help-seeking and first treatment. Interactions between generation and sex were tested within each Cox regression. RESULTS: Significant hazards were found in all 4 transitions. Overall, younger generations used services earlier than older generations, which translated into higher likelihoods of these behaviors. Regardless of generation, younger females were less likely to use services than males. CONCLUSIONS: There are generational and sex differences in service use for alcohol problems among individuals with AUD. Policy and clinical implications are discussed.

The relationship between on-campus service utilization and common mental health concerns in undergraduate college students.

Little research exists into the trends associated with on-campus service utilization for mental health concerns of college students. Rates of broad service utilization exist, but no published study has examined the direct relationship between a range of common mental health symptoms and on-campus service utilization. The aims of the present study are to explore (1) which common mental health concerns are associated with specific on-campus service utilization in undergraduate students and (2) whether endorsement of more mental health concerns will predict a higher number of services utilized. Data were utilized from 3,734 undergraduates at a large (more than 20,000 undergraduates), urban university (Mage = 19.94 years, SD = 0.55 years; female = 66%). Four on-campus services (University Counseling Services, University Health Services, The Wellness Resource Center, and Disability Support Services) were regressed onto mental health concerns associated with symptoms of three disorders (anxiety, depression, alcohol use disorder [AUD]) and two mental health risk factors (stressful life events [SLEs], antisocial behaviors [ASBs]). AUD symptoms predicted the most overall and specific service utilization, followed by depression symptoms and SLEs. Anxiety symptoms and ASBs were not significant predictors when combined with other variables. This is the first study to investigate trends specific to on-campus college student service utilization. Findings will be helpful to mental health professionals on similar college campuses by providing insight into programming and outreach initiatives for these or related services. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Using electronic audience response technology to track e-cigarette habits among college freshmen.

PURPOSE: The use of e-cigarette devices, specifically JUUL, is on the rise on college campuses. Traditional means of collecting and analyzing research may not be fast enough for health professionals to effectively assess, plan, and implement effective prevention/intervention strategies. PROCEDURES: In August 2018, during incoming student orientation sessions at seven different college campuses, data was collected on a specific e-cigarette, JUUL. Data on use and knowledge of JUUL, as well as traditional cigarette use, was collected via immediate electronic audience response devices. Analyses included calculating descriptive statistics for questions of interest. RESULTS: Because response on each item was optional and anonymous, participation on specific questions varied and the total sample size for the questions of interest ranged from 1940 to 2027 students. Mean daily use rates were 13.7% (11.6-18.0%) for JUUL and 1.7% (1.3-2.5%) for cigarettes. Most students (67.3%) knew that JUUL always contained nicotine (38.4-84.5%), although 30.1% believed that it just contained nicotine and/or flavored vapor (15.5-50.0%), and 2.1% thought it was flavored vapor only (0.0-5.9%). CONCLUSIONS: This study reports the highest daily use of e-cigarettes among college students in the literature to date, with past-month e-cigarette use and daily cigarette use on par with previous estimates. Findings also highlight the knowledge gaps that some users have about JUUL specifically. In order for college health educators and professionals to best help students, adoption of methods that allow for more rapid assessment of e-cigarette trends is needed. This will help campuses more effectively address this issue, closing the research-to-practice gap in college health.

The Genetic and Environmental Relationship Between Childhood Behavioral Inhibition and Preadolescent Anxiety.

This study uses novel approaches to examine genetic and environmental influences shared between childhood behavioral inhibition (BI) and symptoms of preadolescent anxiety disorders. Three hundred and fifty-two twin pairs aged 9-13 and their mothers completed questionnaires about BI and anxiety symptoms. Biometrical twin modeling, including a direction-of-causation design, investigated genetic and environmental risk factors shared between BI and social, generalized, panic and separation anxiety. Social anxiety shared the greatest proportion of genetic (20%) and environmental (16%) variance with BI with tentative evidence for causality. Etiological factors underlying BI explained little of the risk associated with the other anxiety domains. Findings further clarify etiologic pathways between BI and anxiety disorder domains in children.

Fear-potentiated startle response as an endophenotype: Evaluating metrics and methods for genetic applications.

The modulation of the startle response (SR) by threatening stimuli (fear-potentiated startle; FPS) is a proposed endophenotype for disorders of the fearful-fearlessness spectrum. FPS has failed to show evidence of heritability, raising concerns. However, metrics used to index FPS-and, importantly, other conditional phenotypes that are dependent on a baseline-may not be suitable for the approaches used in genetic epidemiology studies. Here, we evaluated multiple metrics of FPS in a population-based sample of preadolescent twins (N = 569 from 320 twin pairs, Mage = 11.4) who completed a fear-conditioning paradigm with airpuff-elicited SR on two occasions (~1 month apart). We applied univariate and multivariate biometric modeling to estimate the heritability of FPS using several proposed standardization procedures. This was extended with data simulations to evaluate biases in heritability estimates of FPS (and similar metrics) under various scenarios. Consistent with previous studies, results indicated moderate test-retest reliability (r = 0.59) and heritability of the overall SR (h2 = 34%) but poor reliability and virtually no unique genetic influences on FPS when considering a raw or standardized differential score that removes baseline SR. Simulations demonstrated that the use of differential scores introduces bias in heritability estimates relative to jointly analyzing baseline SR and FPS in a multivariate model. However, strong dependency of FPS on baseline levels makes unique genetic influences virtually impossible to detect regardless of methodology. These findings indicate that FPS and other conditional phenotypes may not be well suited to serve as endophenotypes unless such codependency can be disentangled.

Resting Heart Rate Variability (HRV) in Adolescents and Young Adults from a Genetically-Informed Perspective.

Reduced heart rate variability (HRV) is associated with cardiac morbidity, mortality, and negative psychopathology. Most research concerning genetic influences on HRV has focused on adult populations, with fewer studies investigating the developmental period of adolescence and emerging adulthood. The current study estimated the genetic and environmental contributions to resting HRV in a sample of twins using various HRV time domain metrics to assess autonomic function across two different time measurement intervals (2.5- and 10-min). Five metrics of resting HRV [mean interbeat interval (IBI), the standard deviation of normal IBIs (SDNN), root square mean of successive differences between IBIs (RMSSD), cardiac vagal index (CVI), and cardiac sympathetic index (CSI)] were assessed in 421 twin pairs aged 14-20 during a baseline electrocardiogram. This was done for four successive 2.5-min intervals as well as the overall 10-min interval. Heritability (h2) appeared consistent across intervals within each metric with the following estimates (collapsed across time intervals): mean IBI (h2 = 0.36-0.46), SDNN (h2 = 0.23-0.30), RMSSD (h2 = 0.36-0.39), CVI (h2 = 0.37-0.42), CSI (h2 = 0.33-0.46). Beyond additive genetic contributions, unique environment also was an important influence on HRV. Within each metric, a multivariate Cholesky decomposition further revealed evidence of genetic stability across the four successive 2.5-min intervals. The same models showed evidence for both genetic and environmental stability with some environmental attenuation and innovation. All measures of HRV were moderately heritable across time, with further analyses revealing consistent patterns of genetic and environmental influences over time. This study confirms that in an adolescent sample, the time interval used (2.5- vs. 10-min) to measure HRV time domain metrics does not affect the relative proportions of genetic and environmental influences.