In a large registry-based study investigating medication use in people with substance use disorders, the ADHD medication lisdexamfetamine was associated with the lowest risk of hospitalisation and death in people with amphetamine addiction. The findings, which also showed drugs which worsened outcomes, were published in JAMA Psychiatry.
“Our results suggest that lisdexamfetamine is associated with the best outcomes, and encourage the conduction of randomised controlled trials to explore this further, says first author Jari Tiihonen, professor at Karolinska Institutet.
Worldwide, amphetamines are the second most used illicit drugs and hospitalisations related to its use are rising.
At present, there are no approved pharmacological interventions available for treating amphetamine or methamphetamine addiction. While certain medications have shown promising results, the studies so far have often been small and convincing evidence is lacking.
Registry-based study
In the present study, the researchers investigated the association between generally used medications among persons with substance use disorder and the risk of two primary outcomes in people with amphetamine or methamphetamine use disorder: 1) hospitalisation due to substance use disorder or 2) hospitalisation due to any cause, or death.
The study enrolled nearly 14 000 individuals aged 16 to 64 years in Sweden with a registered first-time diagnosis of amphetamine or methamphetamine use disorder from July 2006 to December 2018. Individuals with schizophrenia or bipolar disorder were excluded.
Patients were followed from diagnosis until they died, emigrated, were diagnosed with schizophrenia or bipolar disorder or the study ended. The median follow-up time was 3.9 years.
Comparing effects in the same individual
The researchers looked at how the risk of hospitalisation or death for each individual differed depending on whether they were on or off the medication at that time.
”Our results show that lisdexamfetamine, a medication approved for treating ADHD and in some countries also for binge eating, was the only specific medication associated with reduced risk of hospitalisation and death,” says first author Milja Heikkinen, researcher at the University of Eastern Finland and Niuvanniemi Hospital.
The risk of hospitalisation due to substance use disorder was 18% lower and the risk of hospitalisation due to any cause or death was 14% lower during periods of lisdexamfetamine use, compared to periods without the ADHD medication.
The combination of two or more different medications for substance use disorder was also associated with a lower risk of hospitalisation or death.
Some medications linked to worse outcomes
Use of benzodiazepines was associated with poorer outcomes; 17% higher risk of hospitalisation due to substance use disorder and 20% higher risk of hospitalisation due to any cause or death, during periods of use compared to periods of non-use. The use of antidepressants was also associated with slightly worse outcomes than non-use.
The researchers note that pharmacological treatments are often discontinued when the clinical state has improved, and are started when the clinical state deteriorates. Therefore, the results may underestimate the putative beneficial effect of treatments. To control for this phenomenon, the researchers conducted analyses by omitting the first 30 days of use. The results were then in line with the main analyses.
Source: Karolinska Institutet
