Summary: A large meta-analysis finds that heightened impulsivity—measured as a stronger preference for smaller immediate rewards over larger delayed rewards, known as delay discounting—is associated with many psychiatric disorders including bipolar disorder, borderline personality disorder, schizophrenia, depression, and several eating disorders.
Source: McMaster University
Overview
Researchers at McMaster University and St. Joseph’s Healthcare Hamilton conducted a comprehensive meta-analysis showing that many psychiatric diagnoses are linked with increased delay discounting, a decision-making pattern tied to impulsivity. The analysis combined data from more than 40 published studies and appears in JAMA Psychiatry. By pooling results across disorders, the study provides stronger evidence that impulsive preference for immediate rewards is a widespread, transdiagnostic behavioral feature in mental illness.
Key findings
The meta-analysis examined monetary delay discounting across eight diagnostic categories, comparing people with psychiatric disorders to control groups. Significant increases in delay discounting—indicating a stronger tendency to choose smaller, immediate rewards—were observed in several conditions, notably bipolar disorder, borderline personality disorder, schizophrenia, major depressive disorder, bulimia nervosa, and binge-eating disorder. In contrast, anorexia nervosa showed the opposite pattern: people with anorexia tended to favor larger delayed rewards, consistent with unusually high self-control over eating behavior.
According to the study authors, these results suggest that delay discounting is best viewed as a continuum. Some disorders are characterized by excessively impulsive decision-making, while others are linked to overly self-controlled choices. Recognizing delay discounting as a cross-cutting mechanism helps clarify similarities and differences across psychiatric diagnoses and points to opportunities for transdiagnostic research and treatment strategies.
Why it matters
Delay discounting is a behavioral-economic measure of impulsive choice. Prior work has linked steep delay discounting with unhealthy outcomes such as addiction, obesity, and ADHD. This meta-analysis expands that evidence base, showing that heightened impulsivity in intertemporal choice is present across a broad set of psychiatric conditions. By identifying delay discounting as a transdiagnostic process, the study encourages psychiatric research that looks beyond single-diagnosis models and toward common neurobiological and genetic mechanisms that drive maladaptive decision-making.
Expert commentary
“The revelation that delay discounting is one of these ‘trans-diagnostic’ processes will have a significant effect on the future of psychiatric diagnosis and treatment,” said Michael Amlung, lead author and assistant professor of psychiatry and behavioural neurosciences at McMaster University. Randi McCabe, co-author and psychologist-in-chief at St. Joseph’s Healthcare Hamilton, noted that examining processes that cut across disorders helps illuminate shared and distinguishing characteristics, guiding research into prevention and treatment.
“The more we understand the nature of psychiatric illness, the better we are equipped to provide effective treatment strategies,” Randi McCabe said.
Implications for research and clinical practice
The authors argue the evidence supports including delay discounting measures in transdiagnostic research frameworks, such as the Research Domain Criteria (RDoC) initiative, which emphasizes biologically grounded constructs across disorders. They call for future studies to investigate the neurobiological and genetic bases of delay discounting, with the goal of informing evidence-based, cross-disorder interventions that target impulsive decision-making.
Funding and acknowledgements
The Peter Boris Centre for Addictions Research, a partnership of St. Joseph’s Healthcare Hamilton and McMaster University, provided partial funding for this research.
Source: McMaster University
Media contacts: Veronica McGuire – McMaster University
Image source: Public domain
Original research: Closed access. Article title: “Delay Discounting as a Transdiagnostic Process in Psychiatric Disorders: A Meta-analysis.” Authors: Michael Amlung, PhD; Emma Marsden, BA; Katherine Holshausen, PhD; Vanessa Morris, BA; Herry Patel, BSc; Lana Vedelago, BA; Katherine R. Naish, PhD; Derek D. Reed, PhD; Randi E. McCabe, PhD. Journal: JAMA Psychiatry. DOI: 10.1001/jamapsychiatry.2019.2102
Abstract (summary)
Delay discounting measures preference for immediate versus delayed rewards and is argued to be a transdiagnostic behavioral process. This meta-analysis searched multiple databases through December 10, 2018, and followed PRISMA guidelines to identify English-language studies that compared monetary delay discounting between psychiatric groups and controls. The final sample included 57 effect sizes from 43 studies across eight diagnostic categories. Random-effects models indicated significantly steeper discounting in people with major depressive disorder, schizophrenia, borderline personality disorder, bipolar disorder, bulimia nervosa, and binge-eating disorder, while anorexia nervosa showed significantly shallower discounting. Modest publication bias was detected for schizophrenia and at the aggregate level. Overall, the findings support delay discounting as a core transdiagnostic process and highlight gaps in some areas such as posttraumatic stress disorder that warrant further study.