An application of analyzing the trajectories of two disorders: A parallel piecewise growth model of substance use and attention-deficit/hyperactivity disorder

Adolescent stress experiences over time study (ASETS) protocol: design and methods of a prospective longitudinal study of sexual minority adolescents in the USA

INTRODUCTION

Sexual minority adolescents (SMA) report higher rates of anxiety, self-harm, depression and suicide than heterosexual peers. These disparities appear to persist into adulthood and may worsen for certain subgroups, yet the mechanisms that drive these concerns remain poorly understood. Minority stress theory, the predominant model for understanding these disparities, posits that poorer outcomes are due to the stress of living in a violently homophobic and discriminatory culture. Although numerous studies report associations between minority stress and behavioural health in adolescence, no study has comprehensively examined how minority stress may change throughout the course of adolescence, nor how stress trajectories may predict health outcomes during this critical developmental period.

METHODS AND ANALYSIS

Between 15 May 2018 and 1 April 2019, we recruited a US national sample of diverse SMA (n=2558) age 14-17 through social media and respondent-driven sampling strategies. A subset of participants (n=1076) enrolled in the longitudinal component and will be followed each 6 months until 1 July 2022. Primary outcomes include symptoms of depression, anxiety and post-traumatic stress disorder; suicidality and self-harm and substance use. The key predictor is minority stress, operationalised as the Sexual Minority Adolescent Stress Inventory. We will use parallel cohort-sequential latent growth curve models to test study hypotheses within a developmental framework.

ETHICS AND DISSEMINATION

All participants provided assent to participate, and longitudinal participants provided informed consent at the first follow-up survey after reaching age 18. All study procedures were reviewed and approved by the University of Southern California Social-Behavioral Institutional Review Board, including a waiver of parental permission given the potential for harm due to unintentional 'outing' to a parent during the consent process. The final anonymous data set will be available on request, and research findings will be disseminated through academic channels and products tailored for the lay community.

Combining behavioral harm-reduction treatment and extended-release naltrexone for people experiencing homelessness and alcohol use disorder in the USA: a randomised clinical trial

BACKGROUND

The rate of alcohol-related mortality in people experiencing homelessness and alcohol use disorder is high and necessitates accessible and effective treatment for alcohol use disorder. However, typical abstinence-based treatments do not optimally engage this population. Recent studies have shown that harm-reduction treatment, which does not require abstinence, but instead aims to incrementally reduce alcohol-related harm and improve health-related quality of life, is acceptable to and effective for this population. The aim of this study was to test the efficacy of combined pharmacological and behavioural harm-reduction treatment for alcohol use disorder (HaRT-A) in people experiencing homelessness and alcohol use disorder.

METHODS

This randomised clinical trial was done at three community-based service sites (low-barrier shelters and housing programmes) in Seattle (WA, USA). Eligible participants were adults (aged 21-65 years) who met the DSM-IV-TR criteria for alcohol use disorder and who experienced homelessness in the past year. Participants were randomly assigned (1:1:1:1) by permuted block randomisation, stratified by site, to receive either HaRT-A plus intramuscular injections of 380 mg extended-release naltrexone (XR-NTX; HaRT-A plus XR-NTX group); HaRT-A plus placebo injection (HaRT-A plus placebo group); HaRT-A alone (HaRT-A alone group); or community-based supportive services as usual (services-as-usual control group). Patients assigned to receive HaRT-A attended sessions at baseline (week 0) and in weeks 1, 4, 8, and 12. XR-NTX and placebo injections were administered in weeks 0, 4, and 8. During the study, participants, interventionists, and investigators were masked to group assignment in the two injection arms. All participants were invited to follow-up assessments at weeks 4, 8, 12, 24, and 36. The primary outcomes were self-reported alcohol use quantity (ie, alcohol quantity consumed on peak drinking occasion, as measured with the Alcohol Quantity Use Assessment questionnaire) and frequency (measured with the Addiction Severity Index), alcohol-related harm (measured with the Short Inventory of Problems-2R questionnaire), and physical and mental health-related quality of life (measured with the Short Form-12 survey). Using piecewise growth modelling and an intention-to-treat model, we compared the effects of the three active treatment groups with the services-as-usual control group, and the HaRT-A plus XR-NTX group with the HaRT-A plus placebo group, over the 12-week treatment course and during the 24 weeks following treatment withdrawal. Safety analyses were done on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, NCT01932801.

FINDINGS

Between Oct 14, 2013, and Nov 30, 2017, 417 individuals experiencing homelessness and alcohol use disorder were screened, of whom 308 were eligible and randomly assigned to the HaRT-A plus XR-NTX group (n=74), the HaRT-A plus placebo group (n=78), the HaRT-A alone group (n=79), or the services-as-usual control group (n=77). Compared with the services-as-usual control group, the HaRT-A plus XR-NTX group showed significant improvements from baseline to 12 weeks post-treatment across four of the five primary outcomes: peak alcohol quantity (linear B -0·48 [95% CI -0·79 to -0·18] p=0·010; full model Cohen's d=-0·68), alcohol frequency (linear B -4·42 [-8·09 to -0·76], p=0·047; full model Cohen's d=-0·16), alcohol-related harm (linear B -2·22 [-3·39 to -1·06], p=0·002; full model Cohen's d=-0·56), and physical health-related quality of life (linear B 0·66 [0·23 to 1·10], p=0·012; full model Cohen's d=0·43). Compared with the services-as-usual control group, the HaRT-A plus placebo group showed significant improvements in three of the five primary outcomes: peak alcohol quantity (linear B -0·41 [95% CI -0·67 to -0·15] p=0·010; full model Cohen's d=-0·23), alcohol frequency (linear B -5·95 [-9·72 to -2·19], p=0·009; full model Cohen's d=-0·13), and physical health-related quality of life (linear B 0·53 [0·09 to 0·98], p=0·050; full model Cohen's d=0·35). Compared with the services-as-usual control group, the HaRT-A alone group showed significant improvements in two of the five primary outcomes: alcohol-related harm (linear B -1·58 [95% CI -2·73 to -0·42] p=0·025; full model Cohen's d=-0·40) and physical health-related quality of life (linear B 0·63 [0·18 to 1·07], p=0·020; full model Cohen's d=0·41). After treatment discontinuation at 12 weeks, the active treatment groups plateaued, whereas the services-as-usual group showed improvements. Thus, during the post-treatment period (weeks 12 to 36), the services-as-usual control group showed greater reductions in alcohol-related harm compared with both the HaRT-A plus XR-NTX group (linear B 0·96 [0·24 to 1·67], p=0·028; full model Cohen's d=0·24) and the HaRT-A alone group (linear B 1·02 [0·35 to 1·70], p=0·013; full model Cohen's d=0·26). During the post-treatment period, the services-as-usual control group significantly improved on mental health-related quality of life compared with the HaRT-A alone group (linear B -0·46 [-0·79 to -0·12], p=0·024; full model Cohen's d=-0·28), and on physical health-related quality of life compared with the HaRT-A plus XR-NTX group (linear B -0·42 [-0·67 to -0·17], p=0·006; full model Cohen's d=-0·27), the HaRT-A plus placebo group (linear B -0·42 [-0·69 to -0·15], p=0·009; full model Cohen's d=-0·27), and the HaRT-A alone group (linear B -0·47 [-0·72 to -0·22], p=0·002; full model Cohen's d=-0·31). For all other primary outcomes, there were no significant linear differences between the services-as-usual and active treatment groups. When comparing the HaRT-A plus placebo group with the HaRT-A plus XR-NTX group, there were no significant differences for any of the primary outcomes. Missing data analysis indicated that participants were more likely to drop out in the services-as-usual control group than in the active treatment groups; however, primary outcome findings were found to be robust to attrition. Participants in the HaRT-A plus XR-NTX, HaRT-A plus placebo, and HaRT-A alone groups were not more likely to experience adverse events than those in the services-as-usual control group.

INTERPRETATION

Compared with existing services, combined pharmacological and behavioural harm-reduction treatment resulted in decreased alcohol use and alcohol-related harm and improved physical health-related quality of life during the 12-week treatment period for people experiencing homelessness and alcohol use disorder. Although not as consistent, there were also positive findings for behavioural harm-reduction treatment alone. Considering the non-significant differences between participants receiving HaRT-A plus placebo and HaRT-A plus XR-NTX, the combined pharmacological and behavioural treatment effect cannot be attributed to XR-NTX alone. Future studies are needed to further investigate the relative contributions of the pharmacological and behavioural components of harm-reduction treatment for alcohol use disorder, and to ascertain whether a maintenance treatment approach could extend these positive outcome trajectories.

FUNDING

National Institute on Alcohol Abuse and Alcoholism.

Anxiety and Depression During Childhood and Adolescence: Testing Theoretical Models of Continuity and Discontinuity

The present study sought to clarify the trajectory (i.e., continuous vs. discontinuous) and expression (i.e., homotypic vs. heterotypic) of anxiety and depressive symptoms across childhood and adolescence. We utilized a state-of-the-science analytic approach to simultaneously test theoretical models that describe the development of internalizing symptoms in youth. In a sample of 636 children (53% female; M _age = 7.04; SD _age = 0.35) self-report measures of anxiety and depression were completed annually by youth through their freshman year of high school. For both anxiety and depression, a piecewise growth curve model provided the best fit for the data, with symptoms decreasing until age 12 (the "developmental knot") and then increasing into early adolescence. The trajectory of anxiety symptoms was best described by a discontinuous homotypic pattern in which childhood anxiety predicted adolescent anxiety. For depression, two distinct pathways were discovered: A discontinuous homotypic pathway in which childhood depression predicted adolescent depression and a discontinuous heterotypic pathway in which childhood anxiety predicted adolescent depression. Analytical, methodological, and clinical implications of these findings are discussed.