
A late-breaking abstract presented at the North American Neuromodulation Society (NANS) 2021 virtual meeting (January 15–16) has shown that non-invasive neuromodulation may present a significant reduction in clinical opiate withdrawal scale (COWS) score.
The results were presented by Carlos Tirado (Austin, USA), chief medical officer at Carmahealth and principle investigator of this study. The focus of the study was on the transcutaneous auricular neurostimulation (tAN) device (the Sparrow Therapy System) for the treatment of opioid withdrawal symptoms.
According to figures presented by Tirado, in the USA, there are 5–8 million people using opioids for chronic pain management, 2.1 million people with an opioid-use disorder, and under one million active heroin users. Tirado stated that there had been a levelling of this opioid trend over the last few years but, “with the pandemic, we have seen an unprecedented increase occurring within a very short period of time.”
Tirado claims that a critical element in the treatment of opioid use disorders (and opioid analgesia for dose modification) is the management of withdrawal. He stated that once dependent, individuals experience withdrawal anywhere from six–12 hours of the use of a short-acting opioid and seven–10 days for longer-acting opioids.
In his presentation, Tirado showed that the two most common symptoms of withdrawal are pain and anxiety. Pain creates a problem because a patient may struggle to tell the difference between withdrawal pain and the pain they originally had the complaint about. Other withdrawal symptoms included chills, nausea, fatigue, cramps, sleeplessness, tremors, muscle tension, increased heart rate, running nose, and yawning. Additionally, patients often describe withdrawal as unbearable and incapacitating and cite fear of withdrawal as a primary reason they continue opioid use.
The study, entitled ‘Using transcutaneous auricular neurostimulation in the reduction of symptoms associated with opioid withdrawal,’ used a wearable non-invasive tAN device placed around the ear connected to a patient controller and app for the doctor. The device targets cranial nerve branches 10 and five.
Tirado reported that they are currently running a larger study. They aim to randomise 40 patients and currently have 26 enrolled. Individuals were admitted to an inpatient drug treatment facility for a five-day drug treatment period. The primary endpoint was a significant reduction in COWS score after 60 minutes. The secondary endpoint of clinically significant reduction of COWS between days two and five. Tertiary endpoints included treatment retention, continuation of treatment, passing a naloxone challenge test, and other patient-reported quality of life measures.
Tirado presented the results from the 26 patients. The mean age was 34.4 years, 65.4% were male, 84.6% were white, the mean duration of opioid use was 12 years, and 92% of patients were using heroin prior to treatment. Common psychiatric comorbidities included depression (38.5%), anxiety (38.5%), and bipolar disorder (30.8%). Tirado described this group as a “very representative sample of opioid users.”
In this group of 26, the COWS scores saw a reduction from baseline by 50.4% at 60 minutes and 54.6% at 120 minutes. On day two, COWS scores were reduced from baseline by 60.8%, 63.8% on day three, 68.3% on day four, and 75% on day five. A total of 92.3% of patients had a 30% or greater reduction in COWS on day one.
The symptoms with the greatest reduction were those parasympathetic neurological symptoms, such as restlessness, which saw an 82.5% reduction from baseline, and tremor, which saw a 73.7% reduction from baseline.
All of the study-completers passed the naloxone challenge on either day three or day five, and 92.9% of study-completers were amenable to continuation of addiction treatment at exit study.
On their findings, Tirado states, “we were able to demonstrate that individuals were more likely to remain engaged and continue to their next phase of treatment.”