Summary: Yes, research shows that experiencing chronic pain can increase risk of opioid addiction.
Key Points:
- Chronic pain is associated with a phenomenon called central sensitization, which increases the reactivity of the nervous system to pain and other external stimuli
- Previous research establishes a connection between chronic pain, central sensitization, and increased risk of relapse to opioid use.
- Chronic pain is also associated with psychological, emotional, and functional outcomes commonly identified as risk factors for addiction.
Opioid Addiction, Opioid Use Disorder (OUD), the Opioid Crisis, and Chronic Pain
The opioid crisis began with a rapid increase in the number of opioid prescriptions for pain written by physicians at the end of the 1990s. There were three main drivers of this development:
- The appearance of new opioid medications.
- A substantial increase in marketing for opioid medications for pain.
- Physicians and pharmaceutical companies downplayed the risk of addiction associated with the new generation of opioid medication.
As a result, rates of opioid addiction and fatal opioid overdose increased dramatically, in a trend that continued for 15 years with no signs of reversal. After a brief decline from 2017-2018, rates of fatal opioid overdose, opioid addiction, and OUD began to trend upward again in 2019, and that trend continued through 2022. Here’s a brief run-down on basic facts related to the opioid overdose crisis:
- 1999-2024: Nearly ¾ of a million people died of opioid overdose
- 2023-2024: Opioid overdose deaths decreased by 34%, the largest drop in fatalities since the onset of the crisis
Although the evidence indicates we may have finally turned a corner, there’s still work to be done to ensure the reduction in overdose deaths between 2023 and 2024 become a trend, rather than an isolated blip in the data.
What’s the Connection Between Chronic Pain, Central Sensitization, and Opioid Addiction?
First, let’s define what we mean when we say central sensitization:
“Central sensitization (CS) is a condition in which the nervous system becomes continually stimulated which causes intensified pain sensations. It is associated with chronic pain progression due to an increased response to neurons in the central nervous system.”
Central sensitization increases the levels of pain that people with chronic pain feel. In turn, higher levels of pain increase and exacerbate the chronic pain experience, and evidence shows chronic pain increases the risk of the following negative consequences:
- Depressive symptoms and major depressive disorder (MDD)
- Anxiety symptoms and generalized anxiety disorder (GAD)
- Suicidality: suicidal ideation and suicide attempts
- Cognitive impairment
- Sleep disturbance
- Decreased quality of life
Those negative consequences are all risk factors for drug addiction, which means they can increase risk of opioid addiction. Based on this set of facts, a group of researchers at the American College of Rheumatology (ACR) designed a study to examine the relationship between chronic pain and opioid addiction.
The research team collected data on the following factors associated with chronic pain from patients in treatment for opioid addiction at a residential treatment center in Ohio:
- Chronic Pain Severity:
- Based on standard metrics established by the ACR
- Chronic Pain Interference in Daily Life:
- Researchers assessed the impact of chronic pain on overall mood, quality of relationships, sleep, and other factors
- Researchers assessed the impact of chronic pain on work and daily activity
- Quality of Life:
- Researchers assessed the impact of chronic pain on factors associated with physical, social, emotional functioning, and overall psychosocial wellbeing
Let’s take a look at what they found.
Chronic Pain and Increased Risk of Opioid Addiction
The first thing the research team wanted to know was whether chronic pain – by way of central sensitization (CS) – was associated with opioid addiction. Results showed that among patients diagnosed with opioid use disorder:
- 88% had chronic pain
- 93% had problems sleeping
- 62% felt tired all the time
- 44% had problems with thinking/decision making.
Those results confirm the connection between opioid addiction, chronic pain and CS. Next, they examined the impact of pain on the general activities of daily life, i.e. pain interference. Results showed that among patients diagnosed with opioid use disorder, chronic pain created problems/impairments with:
- Basic daily activities
- Quality of sleep
- Stability of relationships
- Quality of mood
- Ability to walk comfortably
- Ability to engage in essential vocational tasks
Those results confirm the hypothesis that among people with opioid addiction, chronic pain and CS cause significant functional difficulty. Next, they assessed the impact of pain on overall quality of life. Results showed that among patients diagnosed with opioid use disorder, chronic pain created had a negative impact on the following:
- Physical health
- Mental health
- Emotional health
- Social activity
Those outcomes also confirm what the study authors hypothesized: opioid addiction is correlated with chronic pain, which is exacerbated by CS, and increases problems associated with pain severity, the impact of pain on every day life, and the impact of pain on quality of life.
But does central sensitization – i.e. chronic pain – increase risk of opioid addiction?
Let’s check the results.
Among patients with opioid addiction, researchers identified significant association between the presence of chronic pain and central sensitization with:
- Initiation of opioid use
- Development of opioid addiction
- Escalation of opioid addiction
- Deferred treatment for opioid addiction
- Relapse to opioid use
We’ll discuss these results below.
Chronic Pain and Risk of Opioid Addiction
The outcomes reported in this study are important in that they show a connection between chronic pain and opioid addiction, as mediated by central sensitization in the nervous system. Here’s how the research team characterizes these results:
“This study provides early evidence CS may underlie previously observed connections between clinically salient features of chronic pain and OUD, potentially informing future mechanistic research and precision treatment.”
This can help us support our patients with opioid use disorder (OUD) in several ways:
- Upon intake, we can screen patients for presence of chronic pain and CS
- We can address the psychological, emotional, and social impairments associated with chronic pain and CS during treatment for OUD
- We can collaborate with physicians to develop a pain management plan that accounts for CS and does not involve medications associated with addiction
- While planning aftercare and relapse prevention, we can help patients devise strategies to manage the difficulties associated with chronic pain
In addition, we can help our patients find additional peer support groups beyond the 12-step programs commonly associated with addiction treatment. With guidance, our patients can create a robust social support network for patients with OUD that includes people who have a similar set of experiences: chronic pain, central sensitization, in active recovery. In many cases, being seen and understood – by both providers and peers – can make all the difference on the journey to lifelong, sustainable sobriety.
