Search the Library

Abstract: Exercise is a promising treatment for stimulant use disorder. However, efficacy has not been clearly demonstrated in a general stimulant using population where response to exercise is expected to be heterogeneous. Thus, examination of response heterogeneity to identify subgroups for whom exercise is either clearly indicated or not indicated is of considerable interest as findings will support more effective tailoring of patient treatments in practice and guide future research in stimulant use disorder. A secondary analysis of the Stimulant Reduction Intervention using Dosed Exercise (STRIDE) randomized controlled trial of 302 stimulant using or dependent participants was conducted to identify baseline clinical and demographic characteristics associated with differential response between participants in the exercise and health education control groups. Characteristics (i.e., moderators of treatment response) were identified using an established Best Approximating Modeling (BAM) method. Six moderators of treatment response were identified: Quick Inventory of Depressive Symptomatology – Clinician (QIDS-C) rated total score, exercise test maximum systolic blood pressure, number of lifetime drug treatments, Stimulant Craving Questionnaire (STCQ) total score, Addiction Severity Index (ASI) Family subscale score, and Cognitive and Physical Functioning Questionnaire (CPFQ) total score. For all moderators, the odds ratio of response to exercise vs. health education ranged from 0.32 to 2.52 or more depending on the level of the moderator. Conclusions: These results demonstrate that it is possible to identify pre-treatment patient characteristics that predict statistically and clinically meaningful differential treatment response to exercise. Related protocols: CTN-0037

Abstract:

Exercise may be beneficial for individuals in substance use disorder (SUD) treatment given the higher rates of both medical and psychiatric comorbidity, namely mood and anxiety disorders, compared to the general population. Gender and/or racial/ethnic differences in health benefits and response to prescribed exercise have been reported and may have implications for designing exercise interventions in SUD programs.

Using data from the NIDA Clinical Trials Network Stimulant Reduction Intervention using Dosed Exercise (STRIDE) trial, CTN-0037, gender differences and stimulant withdrawal severity across time were analyzed using linear mixed effects models.

The analysis found that males completed significantly more exercise sessions than females and were more adherent to the prescribed exercise dose of 12 Kcal/Kg/Week. Controlling for age, race/ethnicity, treatment group and stimulant withdrawal severity, there was a significant gender by time interaction for body mass index (BMI), waist circumferences, and heart rate measured prior to exercise sessions. For females, body mass index and waist circumference increased over time, while for males, BMI and waist circumference stayed unchanged or slightly decreased with time. Heart rate over time significantly increased for females at a higher rate than in males. Stimulant withdrawal severity was similar in males and females at baseline but males exhibited a significant decrease over time while females did not. Although baseline differences were observed, there were no time by race/ethnicity differences in physiologic responses.

Conclusions: Gender differences in response to exercise may have implications for developing gender specific exercise interventions in SUD programs.

Related protocols: CTN-0037

Abstract:

The aim of this study was to examine the impact of vigorous intensity, high dose exercise (DEI) on cannabis use among stimulant users compared to a health education intervention (HEI) using data from the Stimulant Reduction Intervention using Dosed Exercise NIDA Clinical Trials Network study (CTN-0037).

Adults (N=302) enrolled in the STRIDE randomized clinical trial were randomized to either the DEI or the HEI. Interventions included supervised sessions three times a week during the Acute phase (12 weeks) and once a week during the Follow-up phase (6 months). Cannabis use was measured at each assessment via Timeline Follow Back and urine drug screens. Cannabis use was compared between the groups during the Acute and Follow-up phases using both the intent-to-treat sample and a complier average causal effects (CACE) analysis.

Approximately 43% of the sample reported cannabis use at baseline. The difference in cannabis use between the DEI and HEI groups during the Acute phase was not significant. During the Follow-up phase, the days of cannabis use was significantly lower among those in the DEI group (1.20 days) compared to the HEI gruop (2.15 days; p=0.04).

Conclusions: Results suggest that there were no significant short-term differences in cannabis use between the two groups. However, there were long-term differences between participants in the DEI and HEI groups. Specifically, those who adhered to the exercise intervention, vigorous intensity, high-dose exercise resulted in less cannabis use at follow-up. Further study on the long-term impact of exercise as a treatment to reduce cannabis use should be considered.

Related protocols: CTN-0037

Abstract:

Exercise is a promising treatment for substance use disorders, yet an intention-to-treat analysis of a large, multi-site study found no reduction in stimulant use for exercise versus health education. Exercise adherence was sub-optimal, therefore secondary post-hoc complier average causal effects (CACE) analysis was conducted to determine the potential effectiveness of adequately dosed exercise.

The STimulant use Reduction Intervention using Dosed Exercise (STRIDE) study was a randomized controlled trial comparing a 12 kcal/kg/week (KKW) exercise dose versus a health education control conducted at 9 residential substance use treatment settings across the U.S. that are affiliated with the National Drug Abuse Treatment Clinical Trials Network. Participants were sedentary but medically approved for exercise, used stimulants within 30 days prior to study entry, and received a DSM-IV stimulant abuse or dependence diagnosis within the past year. A CACE analysis adjusted to include only participants with a minimum threshold of adherence (at least 8.3 KKW) and using a negative-binomial hurdle model focused on 218 participants who were 36.2% female, mean age 39.4 years (SD=11.1), and averaged 13 (SD=9.2) stimulant use days in the 30 days before residential treatment. The outcome was days of stimulant use as assessed by the self-report TimeLine Follow Back and urine drug screen results.

The CACE-adjusted analysis found a significantly lower probability of relapse to stimulant use in the exercise group versus the health education group (41% vs. 55.7%, p<.01) and significantly lower days of stimulant use among those who relapsed (5 days vs. 9.9 days, p<.01).

Conclusions: The CACE efficacy analysis was conducted for the STRIDE study to account for exercise dose in the evaluation of exercise as a potential treatment for stimulant use disorders. This analysis demonstrated statistically significant differences for the probability of stimulant use, such that those who would achieve an adequate exercise dose (defined to be an average of 8.3 KKW or more) have an estimated lower probability of relapsing to any stimulant use. Analyses also demonstrated that, even among those who relapsed, the amount of estimated stimulant use was significantly less among those who would achieve an adequate exercise dose. Together, these results suggest a beneficial effect of exercise in the treatment of stimulant abuse. Further research is warranted to develop strategies for exercise adherence that can ensure achievement of an exercise dose sufficient to produce a significant treatment effect.

Related protocols: CTN-0037

Abstract:

The self-report Concise Associated Symptoms Tracking Scale (CAST-SR) has been validated as a reliable instrument to track symptoms across the domains of irritability, mania, anxiety, panic, and insomnia in depressed outpatients after beginning antidepressant medication. However, its factor structure, validity, and reliability have not yet been tested in other treatment-seeking populations.

This study evaluated the psychometrics of the CAST-SR in a sample of participants in the multisite Stimulant Reduction Intervention Using Dosed Exercise (CTN-0037) trial: individuals with stimulant use disorder receiving aerobic exercise or health education interventions. The CAST-SR loaded only in individuals with primary stimulant use disorders who were prescribed antidepressant medications, not in all individuals with primary stimulant use disorders.

Conclusions: These results demonstrate the factor structure, reliability, and validity of the CAST-SR in a novel population of only individuals with stimulant use disorders receiving both exercise/health education interventions and antidepressant medication. Clinicians treating antidepressant-receiving individuals with comorbid stimulant use disorders may use the CAST-SR to examine changes in symptoms of anxiety, insomnia, irritability, and panic throughout treatment, thereby optimizing treatment outcomes.

Related protocols: CTN-0037

Abstract:

Relatively little has been reported about the physical characteristics, such as cardiorespiratory fitness (CRF) and body composition, of stimulant users. Identifying risk factors associated with the physical health of stimulant users is an important public health issue as new treatments should better address the entire range of health concerns experienced by this population.

This study examined cross-sectional data gathered at baseline from the STimulant Reduction Intervention using Dosed Exercise (STRIDE) study, a multi-site randomized clinical trial that examined exercise as an adjunct to treatment as usual for individuals in residential treatment programs (RTPs). Clients were approached after intake to the RTP. Prior to randomization, eligible individuals underwent a comprehensive screening process that included medical screening, where CRF was assessed through a maximal exercise test (time on treadmill), and a series of baseline examinations assessing domains of substance use and mental health.

Data from 295 individuals with recent stimulant use disorders were analyzed. The mean body mass index (BMI) and waist circumference (WC) for all participants was 27.8 +/- 5.7 kg/m² and 93.5 +/- 14.2 cm, respectively, while the mean time on treatment was 13.7 +/- 2.9 min. Few significant associations were observed between CRF, BMI, or WC and substance use and mental health measures.

Conclusions: Stimulant users in this study presented with low CRF levels and would be considered overweight based on their BMI. These individuals would likely benefit from interventions that address both their stimulant use, as well as their physical health.

Related protocols: CTN-0037

Abstract:

The current study examined differences in substance abuse treatment outcomes among racial and ethnic groups enrolled in the Stimulant Reduction Intervention using Dosed Exercise (STRIDE) trial, a multisite randomized clinical trial implemented through the National Institute on Drug Abuse’s (NIDA’s) Clinical Trials Network (CTN). STRIDE aimed to test vigorous exercise as a novel approach to the treatment of stimulant abuse compared to a health education intervention. A hurdle model with a complier average causal effects (CACE) adjustment was used to provide an unbiased estimate of the exercise effect had all participants been adherent to exercise.

Among 214 exercise-adherent participants, we found significantly lower probability of use for Blacks (z= -2.45, p=.014) and significantly lower number of days of use for Whites compared to Hispanics (z= -54.87, p=<.001) and for Whites compared to Blacks (z= -28.54, p=<.001), which suggests that vigorous, regular exercise might improve treatment outcomes given adequate levels of adherence.

Conclusions: The STRIDE study demonstrated that intensive exercise interventions for people with stimulant use disorders, in community-based addiction treatment, are feasible. Examining race/ethnicity differences in treatment outcomes using novel approaches is important to understanding disparities and what contributes to success. There is a need for engagement strategies for sustaining Blacks in treatment and recruiting them into treatment earlier in life. Vigorous exercise may benefit racial and ethnic minority populations with stimulant use disorder. Future research should focus on intentional inclusion of race/ethnic groups, early in the study design, to test interventions targeted with a specific focus on what works for certain populations.

Related protocols: CTN-0037

Abstract:

This is the primary outcomes article for CTN-0037.

The STimulant Reduction Intervention using Dosed Exercise (STRIDE) study was a randomized clinical trial conducted in 9 residential addiction treatment programs across the United States from July 2010 to February 2013. Of 497 adults referred to the study, 302 met all eligibility criteria, including DSM-IV criteria for stimulant abuse and/or dependence, and were randomized to either a dosed exercise intervention (Exercise) or a health education intervention (Health Education) control, both augmenting treatment as usual and conducted thrice weekly for 12 weeks. The primary outcome of percent stimulant abstinent days during study weeks 4 to 12 was estimated using a novel algorithm adjustment incorporating self-reported Timeline Followback (TLFB) stimulant use and urine drug screens (UDS) data.

Mean percent of abstinent days based on TLFB was 90.8% (SD=16.4%) for Exercise and 91.6% (SD=14.7%) for Health Education participants. Percent of abstinent days using the eliminate contradiction (ELCON) algorithm was 75.6% (SD=27.4%) for Exercise and 77.3% (SD=25.1%) for Health Education. The primary intent-to-treat analysis, using a mixed model controlling for site and the ELCON algorithm, produced no treatment effect (P=0.60). In post hoc analyses controlling for treatment adherence and baseline stimulant use, Exercise participants had a 4.8% higher abstinence rate (78.7%) compared to Health Education participants (73.9%) (P=0.03, number needed to treat=7.2).

Conclusions: The primary analysis indicted no significant difference between exercise and health education. Adjustment for intervention adherence showed modestly but significantly higher percent of abstinent days in the exercise group, suggesting that exercise may improve outcomes for stimulant users who have better adherence to an exercise dose.

Related protocols: CTN-0037

Abstract:

Missing data in substance use disorder (SUD) research pose a significant threat to internal validity. Participants terminate involvement or become less likely to attend intervention and research visits for many reasons, which should be addressed prior to becoming problematic. During a 9-month study targeting stimulant abuse, early dropouts and participant reported attendance barriers led to implementing a structured, pre-randomization protocol with participants about retention and solution-focused strategies (the “Fireside Chat”).

NIDA Clinical Trials Network protocol CTN-0037, Stimulant Reduction Using Dosed Exercise (STRIDE), was a two-arm, multisite randomized clinical trial testing treatment-as-usual for stimulant abuse/dependence augmented by Exercise or Health Education. For both groups, study intervention visits at the site were schedule 3/week for 12 weeks followed by 1/week for 24 weeks. During The Chat, research staff thoroughly reviewed participants’ expectations, and barriers and solutions to retention. Fifteen participants were randomized (to Exercise or Health Education) prior to and fourteen were randomized after Chat implementation. Intervention and monthly follow-up attendance (before and after implementation) were compared at the site (N=29) that developed and rigorously implemented The Chat.

Results found that individuals who participated in The Chat (n=14) attended significantly more intervention visits during weeks 1-12 (p<0.001) and weeks 13-36 (p<0.05) and attended more research visits (p<0.001).

Conclusions: The myriad barriers to research engagement that participants face require careful consideration by all stakeholders involved in research. The time investment for The Chat by potential participants and research staff is not trivial but it could produce important benefits for the study. Indeed, the increased validity of study results when less data are missing and staff time savings as the study progresses (e.g., less need for efforts to contact participants who have missed visits) are both quite important. Cooperative dialogue, beginning early in the recruitment phase and prior to randomization, is critical to engaging and retaining participants in SUD research as the collaborative partners they should be considered to be.

Related protocols: CTN-0037

Abstract:

Social/intimate relationship status and quality are associated with health-promoting behaviors, while living alone or isolated are adversely associated with physical and mental health outcomes. There has been limited investigation of how particular components of one’s social environment – usual living arrangements, satisfaction with those arrangements, and global social and family discord – are related to substance use reduction and intervention adherence.

This study investigated these questions in 270 individuals receiving a study intervention for stimulant abuse/dependence through the multi-site Stimulant Reduction Intervention using Dosed Exercise (CTN-0037) trial.

Using mixed effects modeling, the study found that:

• Socially-discordant individuals used stimulants more often during intervention.
• Women who were dissatisfied living alone also used stimulants more frequently.
• Living with a non-partner was associated with greater intervention adherence.

These results identify sample subgroups with adverse stimulant use and intervention adherence outcomes and suggest areas for future inquiry/intervention.

Related protocols: CTN-0037

Abstract:

This study aimed to determine if current comorbid psychiatric disorders differ in adults with cocaine use disorder, other stimulant (primarily methamphetamine) use disorder, or both, and identify demographic and clinical characteristics in those with increasing numbers of comorbid disorders. Baseline data from participants enrolled in the NIDA Clinical Trials Network’s “Stimulant Reduction Intervention using Dosed Exercise” (STRIDE) study, a multisite randomized controlled trial that compared the efficacy of high intensity exercise and health education, both augmented to substance abuse treatment as usual in adults with stimulant use disorders entering residential treatment settings (N=302). Mood disorders were present in 33.6%, and anxiety disorders in 29.6%, with no differences among stimulant use disorder groups. Panic disorder was more frequently present with other stimulant use disorder. Those with two or more comorbid psychiatric disorders were more often female, white, had more symptoms of depression, greater propensity and risk for suicidal behavior, lower functioning in psychiatric and family domains, lower quality of life, more symptoms with stimulant abstinence and greater likelihood of marijuana dependence. Those with one or more comorbid disorders had more medical disorder burden, lower cognitive and physical functioning, greater pain, and higher rates of other drug dependence.

With current comorbid psychiatric disorders, the morbidity of stimulant use disorders increases. Use of validated assessments near treatment entry, and a treatment plan targeting not only substance use and comorbid psychiatric disorders, but functional impairments, medical disorder burden and pain, may be useful.

Related protocols: CTN-0037

Abstract:

Rates of medical illnesses may be higher among individuals with substance use disorders, complicating their care. This study aimed to expand the understanding of other medical conditions in treatment-seeking adults with stimulant use disorder (SUD) using data from the NIDA Clinical Trials Network study Stimulant Reduction Intervention using Dosed Exercise (STRIDE), a randomized, multisite trial investigating exercise augmentation of treatment as usual.

The analysis examined demographic and clinical characteristics based on the number of self-reported diagnosed medical conditions among participants meeting eligibility criteria (passing medical screening exam and maximal exercise test, non-opioid dependent, no concomitant beta blocker, or opioid replacement therapy). The majority (59%) of study participants (N=302, mean age of all participants: 39 years) did not report any history of other medical problems. Those with two or more conditions were older (mean age 46 years), reported more pain and worse physical functioning, and more psychiatric disorders (average 1.44). Hypertension was more common among participants with cocaine use disorders only (present in 16%) and liver disease was more common in those with cocaine plus other stimulant use disorders (present in 7%).

Conclusions: Despite widely held beliefs that adults with SUD face a heavy burden of physical illness, the majority of STRIDE study participants reported no other medical conditions (though the study sample excluded patients with a serious medical condition that prevented exercise, and therefore may be less representative of the general population of those with SUD). A subpopulation had an overall higher burden of illness with worsened physical and psychiatric functioning. Provision of coordinated care may optimize treatment outcomes for patients based on medical comorbidity burden as well as type of drug abused, although these conclusions should be considered preliminary as they are based on self-reported data.

Related protocols: CTN-0037

Abstract:

Current U.S. population surveys indicate more general drug use and higher rates of illicit drug dependence for men than women, however studies also suggest that, for stimulant use, female users exceed males on the severity of dependence, and addiction severity at treatment entry for drug abuse has been linked to poorer outcomes in clinical samples.

This secondary analysis of a stimulant abusing or dependent residential treatment sample (N=302) participating in the National Drug Abuse Treatment Clinical Trials Network study CTN-0037 ( Stimulant Reduction Intervention using Dosed Exercise (STRIDE)) examined gender-specific factors associated with stimulant abstinence severity.

Bivariate statistics tested gender differences in stimulant abstinence symptoms, measured by participant-reported experiences of early withdrawal. Multivariate linear regression examined gender and other predictors of stimulant abstinence symptom severity. Women compared to men reported greater stimulant abstinence symptom severity. Anxiety disorders and individual anxiety-related abstinence symptoms accounted for this difference. African American race/ethnicity was also predictive of lower stimulant abstinence severity.

Conclusions: This study identified differences between men and women on measures of stimulant use and associated disorders, finding greater stimulant abstinence symptom severity in women compared to men. This study also suggests anxiety-related withdrawal experiences as salient topics for clinicians to address in treatment to reduce abstinence symptoms and potentially the risk for relapse to stimulant use.

Related protocols: CTN-0037

Abstract:

Comorbid physical and mental health problems are associated with poorer substance abuse treatment outcomes; however, little is known about these conditions among stimulant abusers at treatment entry. This study compared racial and ethnic groups on baseline measures of drug use patterns, comorbid physical and mental health disorders, quality of life, and daily functioning among cocaine and stimulant abusing/dependent patients. Baseline data from a multi-site, randomized clinical trial of vigorous exercise as a treatment strategy for a diverse population of stimulant abusers (N=290) were analyzed (National Drug Abuse Treatment Clinical Trials Network protocol CTN-0037).

Significant differences between groups were found on drug use characteristics, stimulant use disorders, and comorbid mental and physical health conditions. White, Black, and Hispanic participants reported varied demographic characteristics, substance use patterns and diagnoses, and comorbid mental and physical health conditions. Blacks were more likely to use alcohol and to be diagnosed with a cocaine use disorder only, whereas Whites were more likely to use methamphetamines and a variety of other illicit drugs and to be diagnosed with both a cocaine and other stimulant use disorder or other stimulant use disorder only. Hispanics, similar to Blacks, were more likely to use alcohol, but their rates of methamphetamine use and diagnoses for cocaine and other stimulant use disorder or other stimulant use disorder only fell in between Whites and Blacks. Additionally, Blacks in this study reported fewer psychiatric disorders and symptoms of depression, and better mental health status and well-being than Whites or Hispanics; however, they also reported more comorbid medical conditions, poorer health status, and lower physical and cognitive functioning than other groups. This may be related to barriers to quality medical services for Blacks.

Conclusions: These findings offer implications for stimulant use treatment. They highlight the usefulness of integrating mental and physical health services into substance abuse treatment programs serving racially and ethnically diverse patients. Receipt of primary medical care is associated with lower addiction severity and suggests that efforts to link treatment-seeking substance abusers to primary medical care services should be considered. Integrating mental and physical health care into substance use disorder treatment while paying attention to differences in racial and ethnic groups could have a substantial impact on treatment outcomes.

Related protocols: CTN-0037

Abstract:

Measurement of pain is important in both clinical and research samples, yet while several tools have been developed to aid in the measurement of pain, no gold standard brief pain assessment is universally utilized. As part of the National Drug Abuse Treatment Clinical Trials Network study CTN-0037, “Stimulant Reduction Intervention Using Dosed Exercise (STRIDE),” a new brief, self-administered measurement of pain frequency, intensity, and burden was developed for potential use in both research and clinical settings. This article describes the development and initial psychometric properties of the instrument, the Pain Frequency, Intensity, and Burden Scale (P-FIBS). The P-FIBS was administered to all participants (N=302) with psychostimulant use disorders enrolled in the multisite STRIDE trial. The four items on the P-FIBS all demonstrated high item-total correlations (range 0.70-0.85) with a high Cronbach’s alpha (0.90). The P-FIBS also demonstrated a strong negative correlation with the bodily pain sub-score of the Short Form Health Survey (r=-0.76, p<0.0001) and did not correlate with a measure of cocaine (r=0.09, p=0.12) or methamphetamine (r=-0.06, p=0.33) craving.

Conclusions: The P-FIBS demonstrates good psychometric properties. This brief measure can be used to assess pain in research settings or as a screen in clinical settings. Further research is needed to assess the measure’s sensitivity to change with treatment.

Related protocols: CTN-0037