The downward spiral of chronic pain, prescription opioid misuse, and addiction: cognitive, affective, and neuropsychopharmacologic pathways

Abstract

Prescription opioid misuse and addiction among chronic pain patients are emerging public health concerns of considerable significance. Estimates suggest that more than 10% of chronic pain patients misuse opioid analgesics, and the number of fatalities related to nonmedical or inappropriate use of prescription opioids is climbing. Because the prevalence and adverse consequences of this threat are increasing, there is a pressing need for research that identifies the biobehavioral risk chain linking chronic pain, opioid analgesia, and addictive behaviors. To that end, the current manuscript draws upon current neuropsychopharmacologic research to provide a conceptual framework of the downward spiral leading to prescription opioid misuse and addiction among chronic pain patients receiving opioid analgesic pharmacotherapy. Addictive use of opioids is described as the outcome of a cycle initiated by chronic pain and negative affect and reinforced by opioidergic-dopamingeric interactions, leading to attentional hypervigilance for pain and drug cues, dysfunctional connectivity between self-referential and cognitive control networks in the brain, and allostatic dysregulation of stress and reward circuitry. Implications for clinical practice are discussed; multimodal, mindfulness-oriented treatment is introduced as a potentially effective approach to disrupting the downward spiral and facilitating recovery from chronic pain and opioid addiction.

Keywords: Addiction; Allostasis; Attentional bias; Chronic pain; Default mode; Mindfulness; Opioid misuse; Reward.

Figure 1

The Downward Spiral of Chronic Pain and Opioid Addiction. In brief, the problem of co-occurring chronic pain and opioid addiction involves a cycle of behavioral escalation in which nociception triggers pain hypervigilance and catastrophizing, amplifying pain with emotional anguish. Among affectively dysregulated individuals, recurrent self-administration of opioids in response to pain and negative emotions results in associative learning processes that bias attention towards opioid-related cues (e.g., a sight of a pill bottle), strengthening the automatic habit of opioid use despite tolerance to opioid analgesia. Chronic pain and prolonged opioid misuse causes allostatic changes to stress and reward circuitry in the brain, increasing sensitivity to pain and decreasing the pleasure derived from healthful objects and events. As functional connectivity between the default mode network and other neural circuits changes over time, the sense of self may become entwined with pain-laden narratives and entrapped by a compulsive drive for relief. This downward spiral may ultimately result in mindless, uncontrolled opioid use and addiction.