New York State Suicide Prevention Conference September 19th, 2017 Subtypes of substance users and suicide behaviors: An adolescent risk profile Michael A. Lindsey, PhD, MSW, MPH Director, McSilver Institute for Poverty Policy and Research Constance and Martin Silver Professor of Poverty Studies NYU Silver School of Social Work

All speakers, associated with this continuing education activity, have indicated that they have no financial arrangement or affiliation with any commercial entity whose products, research or services may be discussed in this presentation.

Key Questions How can we use secondary data to examine the risk/profile of adolescents who engage in suicidal behaviors? What type of substance use behaviors in youth may lead to increased risk for suicide?

Prevalence Among U.S. youth age 15-19, suicide is the second leading cause of death (19.2% of deaths) National Vital Statistics Reports; Vol 65 No 5. Hyattsville, MD: National Center for Health Statistics, 2016 From 2008 to 2015, the number of youth aged 5-17 admitted to children’s hospitals for suicidal thoughts or self-harm more than doubled Plemmons et al., 2017

Cultural & Gender Considerations Suicide is not only a “White” phenomenon Increasing rates among ethnic minority youth, especially Black boys and Latina adolescents In 2014, males aged 15 to 19 were approx. 3x more likely than females to die by suicide (CDC, 2015)

Suicide Rates for Adolescents Ages 15–19 Years, 1975–2015 *Suicide rates for adolescents have been rising since 2007 Source: CDC - National Vital Statistics System

Suicide and Substance Use Studies have found that up to 70% of adolescents who completed suicide were drug or alcohol users Miller et al., 1991 Odds of attempting suicide are 2.8-4.8x greater for adolescents (age 13-18) with substance disorders Nock et al., 2013

Types of Suicidal Behaviors Suicidal Ideation: Serious consideration or thoughts of suicide attempt Suicide Plan: Making a plan about how one would attempt suicide Suicide Attempt: A non-fatal, potentially injurious behavior with an intent to die * As captured by the Youth Risk Behavior Survey (YRBS)

Typologies of Substance Use Experimentation Regular use (Daily or Almost Daily) Abuse Dependence Substance Use Disorder

Polysubstance use Usage of multiple substances or “joint” usage Considers the number and types of substances Correlated with other behavioral health issues in adolescents (i.e. sexual risk behaviors, internalizing symptoms)

Methods and Analytic Directions Background on Dataset and Sample Step 1: Latent Class Analysis (LCA) on Substance Use Behaviors Step 2: What is the relationship between Profiles of Substance Users and Suicidal Behaviors? Multinomial Logistic Regression

Dataset 2015 Youth Risk Behavior Survey (YRBS) National epidemiological assessment of Youth Risk Behavior Surveillance System (YRBSS) 9th – 12th grade students of all public, Catholic, and other private school; in 50 States and the District of Columbia Three-stage cluster sample design, representative sample Estimate national rates of health-related behaviors School response rate: 125/180 = 69% Student response rate: 16,624/18,165 = 86% Overall response rate: 69% * 86% = 60%

Sample Final Weighted Sample Size: 15,555 students Gender: Male (50.7%); Female (49.5%) Racial/ethnic Distribution: Black 12.4% Hispanic/Latino: 22.0% White: 56.1% Age: Majority: 15 years old (26.7%), 16 years old (24.7%), 17 years old (23.5%)

Substance Use Indicators Demographic variables Measures Constructs Measures # of items Substance Use Indicators Marijuana Use Age at Initiation 5 Lifetime and Current (past 30 days) Use Cigarette Use No. of cigarette smoked per day in the past 30 days 4 Alcohol Use Largest No. of alcoholic drinks in a row in past 30 days Suicidal Behaviors Suicidal Ideation (0 = No, 1 = Yes) 1 Suicide Plan (0 = No, 1 = Yes) Suicide Attempt (0 = No, 1 = Yes) Covariates Demographic variables Gender (0=Male, 1=Female) 2 Race/ethnicity (Black, Hispanic/Latino, White) 3 Age (<=12, 13, 14, 15, 16, 17, >=18) 7

Analyses Latent Class Analysis (LCA) Person-centered methodological approach To identify homogeneous subgroups within heterogeneous population 3-step approach (Asparouhov and Muthén 2013; Vermunt 2010) Use substance use indicators to estimate the latent class model Estimation of the most likely class using latent class probabilities Multinomial logistic regression of the most likely class on demographic/suicidal behaviors variables The final number of latent classes was determined by the agreement with substantive theory (i.e. dual-factor model), empirical evidence, statistical model fit indices including the Akaike’s Information Criterion (AIC; Akaike 1987), Bayesian Information Criterion (BIC; Schwartz 1978), adjusted BIC (Sclove 1987), Lo–Mendell–Rubin test (LMR; Lo et al. 2001), entropy statistic, and mean responses to each scale by class. The bootstrap likelihood ratio test (BLRT) was not utilized as model fit criteria, as it is unavailable in Mplus with data that have a complex survey structure.

Analyses (Con’t) Unknown latent class – exploration approach estimates one to six latent classes Account for complex survey design: correcting SE and Chi-square tests based on stratification, unequal probability selection, non-independence observations Ordered-categorical Outcomes: Weighted Least Squares Means and Variances (WLSMV) Missing Data: Maximum likelihood with robust SE Model Fit Criteria: BIC, Adj. BIC, AIC, LMR, Entropy; substantive theory Mplus version 7.4

Fit Statistics and Model Selection Number of Classes AIC BIC Adjusted BIC LMR (p) Entropy 1 317996.988 318287.938 318167.176 N/A 2 235975.138 236564.694 236319.993 81882.43 (.00) 0.989 3 220022.201 220910.362 220541.723 15988.48 (.76) 0.984 4 206798.310 207985.077 207492.498 13266.66 (.00) 0.963 The adjusted BIC values decreased until a five-class solution was found. The five-class model was examined, but the best log-likelihood value was not replicated even with increased random starts. Therefore, it was not considered for the final model as the solution may not be trustworthy due to local maxima. The LMR of the three-class model was non-significant, meaning the two-class model cannot be rejected, while the LMR of the four-class model was significant again, meaning the three-class model can be rejected in favor of the four-class model. Comparing the four-class model with two-class model, the four-class model had lower AIC, BIC and Adjusted BIC. The entropy of the four-class model was 0.963. An entropy level 0.6 and higher indicates good class separation (Asparouhov and Muthén 2013). Based on these factors and examination of the substantive meaningfulness of the classes, the four-class model was retained and four lifestyle classes were identified. * Best log-likelihood value of the five-class model was not replicated even with increased random starts.

Classifications Class 1: Nonusers Class 2: Moderate Polysubstance Users Class 3: Frequent Polysubstance Users Class 4: Experimental Polysubstance Users

Four-Class LCA Model: Conditional Probabilities of Substance Use by Class SUBSTANCE USE ITEMS Latent Class 1 Latent Class 2 Latent Class 3 Latent Class 4 (n =4415, 28.26%) (n = 1635, 10.47%) (n = 3784, 24.22%) (n = 5790, 37.06%) Nonusers Moderate Users Frequent Users Experimenters Marijuana Age at Initiation Never tried marijuana 0.945 0.373 0.132 0.577 8 or 10 years old 0.002 0.030 0.019 11 or 12 years old  0.003 0.075 0.144 0.040 13 or 14 years old  0.224 0.311 0.161 15 or 16 or 17 or years older 0.031 0.298 0.281 0.203 Lifetime and Current (30 ds) Use Never used 1.000 0.000 0.159 No recent use 0.445 0.168 1 or 2 times 0.302 0.232 3 to 9 times 0.173 0.222 More than 10 times 0.080 0.219

Four-Class LCA Model: Conditional Probabilities of Substance Use by Class SUBSTANCE USE ITEMS Latent Class 1 Latent Class 2 Latent Class 3 Latent Class 4 (n =4415, 28.26%) (n = 1635, 10.47%) (n = 3784, 24.22%) (n = 5790, 37.06%) Nonusers Moderate Users Frequent Users Experimenters Cigarette Age at Initiation Never tried marijuana 0.988 0.740 0.000 0.802 8 or 10 years old 0.002 0.027 0.155 0.030 11 or 12 years old  0.025 0.150 0.032 13 or 14 years old  0.081 0.294 0.063 15 or 16 or 17 or years older 0.006 0.127 0.400 0.073 Lifetime and Current (30 ds) Use Never used 0.964 0.584 0.681 No recent use 0.036 0.416 0.319 1 or 2 times 0.375 3 to 9 times 0.232 More than 10 times 0.393

Four-Class LCA Model: Conditional Probabilities of Substance Use by Class SUBSTANCE USE ITEMS Latent Class 1 Latent Class 2 Latent Class 3 Latent Class 4 (n =4415, 28.26%) (n = 1635, 10.47%) (n = 3784, 24.22%) (n = 5790, 37.06%) Nonusers Moderate Users Frequent Users Experimenters Cigarette No. of cigarette smoked per day Did not smoke cigarettes in 30 ds 1.000 0.000 Less than 1 – 1 per day 0.487 2-5 cigarettes/day 0.326 6 to more than 20 cigarettes/day 0.187 Alcohol Age at Initiation Never drank alcohol 0.986 0.017 0.044 0.085 8 or 10 years old 0.004 0.134 0.222 0.114 11 or 12 years old  0.129 0.153 0.107 13 or 14 years old  0.002 0.314 0.330 0.258 15 or 16 or 17 or years older  0.407 0.250 0.436

Four-Class LCA Model: Conditional Probabilities of Substance Use by Class SUBSTANCE USE ITEMS Latent Class 1 Latent Class 2 Latent Class 3 Latent Class 4 (n =4415, 28.26%) (n = 1635, 10.47%) (n = 3784, 24.22%) (n = 5790, 37.06%) Nonusers Moderate Users Frequent Users Experimenters Alcohol Lifetime and Current (30 ds) Use Never used 0.921 0.000 0.037 0.106 No recent drink (0 days) 0.079 0.131 0.894 1 or 2 days 0.623 0.271 3 to 9 days 0.332 0.391 More than 10 days 0.045 0.170 Largest No. of alcohol in a row Did not drink in the past 30 d 1.000 0.159 1-5 drinks/row 0.647 0.281 6-9 drinks/row  0.272 0.341 10 or more drinks/row 0.080 0.219

Demographic Covariates & Suicidal Behaviors Subtypes of Substance Users & Demographic Covariates/Suicidal Behaviors Reference Group = Class 4 (Experimenters) Demographic Covariates & Suicidal Behaviors Nonusers Moderate Users Frequent Users b (OR) SE p Age -0.36 (0.70) 0.04 0.00 0.08 (1.09) 0.07 0.17 (1.19) 0.05 Sex (Male = 1) 0.11 (1.12) 0.10 0.25 -0.01 (0.99) 0.11 0.90 0.51 (1.67) Black -0.01 (1.00) 0.20 0.98 0.04 (1.04) 0.18 0.83 -0.61 (0.54) 0.22 0.01 Hispanic/Latino -0.31 (0.74) 0.17 0.25 (1.29) 0.16 0.12 -0.22 (0.80) 0.13 White 0.12 (1.13) 0.45 0.38 (1.47) 0.19 0.23 (1.26) 0.24 Suicidal Ideation -0.33 (0.72) 0.14 0.02 0.30 (1.36) 0.53 (1.71) Suicide Plan -0.51 (0.60) -0.11 (0.89) 0.54 0.18 (1.19) 0.32 Suicide Attempt 0.09 (1.10) 0.23 0.69 0.57 (1.78) 1.23 (3.41)

Demographic Covariates & Suicidal Behaviors Subtypes of Substance Users & Demographic Covariates/Suicidal Behaviors Reference Group = Class 1 (Nonusers) Demographic Covariates & Suicidal Behaviors Moderate Users Frequent Users Experimenters b (OR) SE p Age 0.44 (1.55) 0.03 0.00 0.53 (1.70) 0.05 0.36 (1.43) 0.04 Sex (Male = 1) -0.12 (0.88) 0.12 0.32 0.40 (1.50) -0.11 (0.90) 0.10 0.25 Black 0.04 (1.04) 0.20 0.83 -0.61 (0.54) 0.01 (1.01) 0.98 Hispanic/Latino 0.56 (1.75) 0.18 0.09 (1.09) 0.17 0.61 0.31 (1.36) 0.07 White 0.26 (1.30) 0.16 0.11 (1.12) 0.23 0.64 0.45 Suicidal Ideation 0.64 (1.89) 0.87 (2.38) 0.15 0.33 (1.39) 0.14 0.02 Suicide Plan 0.39 (1.48) 0.13 0.68 (1.98) 0.51 (1.66) Suicide Attempt 0.48 (1.62) 0.21 1.14 (3.12) -0.09 (0.91) 0.69

Demographic Covariates & Suicidal Behaviors Subtypes of Substance Users & Demographic Covariates/Suicidal Behaviors Reference Group = Class 2 (Moderate Users) Demographic Covariates & Suicidal Behaviors Nonusers Frequent Users Experimenters b (OR) SE p Age -0.44 (0.64) 0.03 0.00 0.09 (1.09) 0.05 0.07 -0.08 (0.92) 0.04 Sex (Male = 1) 0.12 (1.13) 0.12 0.32 0.53 (1.69) 0.08 0.01 (1.01) 0.11 0.90 Black -0.04 (0.96) 0.20 0.83 -0.65 (0.52) 0.21 0.18 Hispanic/Latino -0.56 (0.57) -0.47 (0.62) 0.15 -0.25 (0.78) 0.16 White -0.26 (0.77) 0.10 -0.15 (0.86) 0.17 0.39 -0.38 (0.68) 0.19 Suicidal Ideation -0.64 (0.53) 0.23 (1.26) 0.14 0.09 -0.30 (0.74) 0.13 0.02 Suicide Plan -0.39 (0.68) 0.29 (1.34) 0.11 (1.12) 0.54 Suicide Attempt -0.48 (0.62) 0.65 (1.92) -0.57 (0.56)

Demographic Covariates & Suicidal Behaviors Subtypes of Substance Users & Demographic Covariates/Suicidal Behaviors Reference Group = Class 3 (Frequent Users) Demographic Covariates & Suicidal Behaviors Nonusers Moderate Users Experimenters b (OR) SE p Age -0.53 (0.59) 0.05 0.00 -0.09 (0.92) 0.07 -0.17 (0.84) Sex (Male = 1) -0.40 (0.67) 0.12 0.08 -0.51 (0.60) 0.10 Black 0.61 (1.84) 0.32 0.65 (1.92) 0.21 0.61 (1.85) 0.22 0.01 Hispanic/Latino 0.17 0.61 0.47 (1.60) 0.15 0.22 (1.25) 0.13 White -0.11 (0.89) 0.23 0.64 0.15 (1.16) 0.39 -0.23 (0.79) 0.20 0.24 Suicidal Ideation -0.87 (0.42) 0.14 0.09 Suicide Plan -0.68 (0.51) -0.29 (0.75) 0.19 -0.18 (0.84) 0.18 Suicide Attempt -1.14 (0.32) -0.65 (0.52) -1.23 (0.29) 0.16

Summary of Results Compared to the nonusers’ class, all three other groups had a higher likelihood of engagement in suicidal behaviors Adolescents in the frequent polysubstance users group exhibited the highest odds of suicidal ideation, suicide plan, and suicide attempt

Implications Screening and prevention programs for adolescents should assess for substance use along the spectrum of lifetime occurrence, current use, and frequency Education on Risks/Profiles Moderate and experimental polysubstance users are also at greater risk for suicidal behaviors

Thank you! Michael A. Lindsey, PhD, MSW, MPH Director Michael.Lindsey@nyu.edu