HJNO May/Jun 2022

DRUG ADDICTION 22 MAY / JUN 2022 I  HEALTHCARE JOURNAL OF NEW ORLEANS   the result of a person’s moral failing or weakness of character, rather than a “real” disease [3]. These attitudes created barri- ers for people with substance use problems to access evidence-based treatments, both those available at the time, such as opioid agonist maintenance, cognitive behav- ioral therapy-based relapse prevention, community reinforcement or contingency management, and those that could result from research. To promote patient access to treatments, scientists needed to argue that there is a biological basis beneath the challenging behaviors of individuals suffer- ing from addiction. This argument was par- ticularly targeted to the public, policymak- ers and health care professionals, many of whom held that since addiction was a mis- ery people brought upon themselves, it fell beyond the scope of medicine, and was nei- ther amenable to treatment, nor warranted the use of taxpayer money. Present-day criticism directed at the conceptualization of addiction as a brain disease is of a very different nature. It originates from within the scientific community itself, and asserts that this conceptualization is neither sup- ported by data, nor helpful for people with substance use problems [4–8]. Addressing these critiques requires a very different per- spective, and is the objective of our paper. We readily acknowledge that in some cases, recent critiques of the notion of addiction as a brain disease as postulated originally have merit, and that those critiques require the postulates to be re-assessed and refined. In other cases, we believe the arguments have less validity, but still provide an opportunity to update the position of addiction as a brain disease. Our overarching concern is that questionable arguments against the notion of addiction as a brain disease may harm patients, by impeding access to care, and slowing development of novel treatments. A premise of our argument is that any useful conceptualization of addiction requires an understanding both of the brains involved, and of environmental fac- tors that interact with those brains [9]. These environmental factors critically include availability of drugs, but also of healthy alternative rewards and opportunities. As we will show, stating that brain mechanisms are critical for understanding and treating addiction in no way negates the role of psy- chological, social and socioeconomic pro- cesses as both causes and consequences of substance use. To reflect this complex nature of addiction, we have assembled a teamwith expertise that spans frommolec- ular neuroscience, through animal models of addiction, human brain imaging, clinical addiction medicine, to epidemiology. What brings us together is a passionate commit- ment to improving the lives of people with substance use problems through science and science-based treatments, with empir- ical evidence as the guiding principle. To achieve this goal, we first discuss the nature of the disease concept itself, and why we believe it is important for the science and treatment of addiction. This is followed by a discussion of the main points raised when the notion of addiction as a brain disease has come under criticism. Key among those are claims that spontaneous remission rates are high; that a specific brain pathology is lacking; and that people suffering from addiction, rather than behaving “compul- sively”, in fact show a preserved ability to make informed and advantageous choices. In the process of discussing these issues, we also address the common criticism that viewing addiction as a brain disease is a fully deterministic theory of addiction. For our argument, we use the term “addiction” as originally used by Leshner [1]; in Box 1, we map out and discuss how this construct may relate to the current diagnostic catego- ries, such as Substance Use Disorder (SUD) and its different levels of severity (Fig. 1). What is a disease? In his classic 1960 book “The Disease Concept of Alcoholism”, Jellinek noted that in the alcohol field, the debate over the disease concept was plagued by too many definitions of “alcoholism” and too few Fig. 1: A heuristic Venn diagram of the putative relationships among risky (hazardous) substance use, substance use disorder (SUD), and addiction. Risky (hazardous) substance use refers to quantity/frequency indicators of consumption; SUD refers to individuals who meet criteria for a DSM-5 diagnosis (mild, moderate, or severe); and addiction refers to individuals who exhibit persistent difficulties with self-regulation of drug consumption. Among high-risk individuals, a subgroup will meet criteria for SUD and, among those who have an SUD, a further subgroup would be considered to be addicted to the drug. However, the boundary for addiction is intentionally blurred to reflect that the dividing line for defining addiction within the category of SUD remains an open empirical question.