The Utility of the CPT in the Diagnosis of ADHD in Individuals with Substance Abuse: A Systematic Review

Abstract

Background: Early identification of attention-deficit/hyperactivity disorder (ADHD) in individuals with substance use disorders (SUD) is important because ADHD has an adverse effect on the development and course of SUD. Given the limited validity of self-report measures of ADHD in individuals with SUD, it is important to investigate the utility of the continuous performance test (CPT) in classifying ADHD in adults with SUD. Objective: This review aims to examine the quantitative similarities and differences in CPT performance of adults with ADHD, SUD, and their comorbidity to determine if a distinct neurocognitive profile exists for each. Method: A systematic review of CPT studies that included patients with the comorbidity of ADHD and SUD and a comparison group of one of the disorders alone was conducted. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. Results: Eight studies were identified with sample sizes ranging from n = 17 to n = 386. The comorbidity of ADHD and SUD was, mostly, not associated with higher rates of commission and omission errors than either disorder alone. However, the comorbidity of ADHD and SUD was more likely to be associated with increased deficits in response time variability compared with individuals with ADHD alone. Conclusions: This review highlights the shortage of large-scale CPT research involving patients with ADHD and SUD. The CPT might be sensitive to attentional deficits, but it lacks specificity for the classification of adult ADHD, SUD, or their comorbidity, and the CPT is thus not useful in discriminating comorbid ADHD and SUD from either disorder alone. Future CPT research should explore whether specific attentional deficits account for the development and persistence of SUD. Such research should also reach beyond traditional CPT measures and include other cognitive and behavioral deficits that were associated with ADHD, such as distractibility and hyperactivity.

The International Collaboration on ADHD and Substance Abuse (ICASA): Mission, Results, and Future Activities

“…In the CASP study, we collected data with a novel continuous performance test [23] in SUD patients with and without ADHD. Results from this study can be found in this special issue of European Addiction Research [24].…”

Conner’s Continuous Performance Test and Adult ADHD: A Systematic Literature Review

“…The present study summarized the most recent research on the CCPT in adults. The reviews conducted to date on the CCPT in adults with ADHD have focused on comorbid substance abuse populations (Slobodin, 2020) and the performance of the CCPT in response to stimulant medications (Riccio et al, 2001). In addition, the present review investigated the reliability and validity of the CCPT for diagnosing ADHD in adults.…”

“…This review highlights the mixed findings on the use of the CCPT in adult ADHD diagnosis. Various reasons may explain why previous reviews on adult (Riccio et al, 2001; Slobodin, 2020) ADHD samples found mixed findings for the diagnostic utility of the CCPT for ADHD. Riccio and Reynolds (2001) noted that continuous performance tests are sensitive to general neurocognitive deficits, such as attention, which is a deficit in several disorders (e.g., ADHD, learning disorders, and depression).…”

“…The authors noted that the combination of objective measures of active with the CPT yielded better results than the CPT alone. The few reviews on the CCPT in adults with ADHD found the measure is ineffective at discriminating ADHD from substance use disorder (SUD; Slobodin, 2020). Likewise, Riccio and Reynolds (2001) found the CCPT has broad sensitivity to detect central nervous system dysfunction, but lacks specificity to discriminate ADHD from other neurodevelopmental disorders.…”

“…Despite concerns regarding the utility of the CCPT in aiding in diagnosing ADHD in adults (Barkley, 2019), there is a paucity of research reviewing the subject. Considering the limited scope of the previous CCPT reviews in adults (Riccio & Reynolds, 2001; Slobodin, 2020), the present study sought to summarize the most recent research on the CCPT in adults and provide an update to Riccio and Reynolds (2001) review. We discuss the utility of the CCPT for diagnosing ADHD in adults in sections, including issues of validity, reliability, and other important factors (e.g., feigning).…”