Young patients might be at increased risk of suicidal behavior, unintentional overdose, injuries, and traffic incidents during treatment periods with gabapentinoids, compared with periods without treatment with those medications, a cohort study of almost 200,000 people shows. Pregabalin is associated with higher hazards of those outcomes than is gabapentin, and the associations are strongest in patients aged 15-24 years, the researchers reported.
“If our findings are triangulated with other forms of evidence, ,” wrote Yasmina Molero, PhD, and associates. “Further restrictions for off-label prescription may need consideration.” The study was published in BMJ.
The use of gabapentinoids has risen in the United States (JAMA Intern Med. 2018;178[2]:292-4), and overdose deaths tied to gabapentin have led some states to explore reclassification of the drug as a controlled substance (Risk Manag Healthc Policy. 2018;11:109-16). In the United Kingdom, gabapentinoids are being reclassified as a class C controlled drug because of concerns about the risk of addiction, overdose, and safety, wrote Dr. Molero of the department of psychiatry at Warneford Hospital at the University of Oxford, England, and associates.
To study associations between gabapentinoids and adverse outcomes related to coordination, mental health, and criminality, Dr. Molero and her associates analyzed data from 191,973 people from the Swedish Prescribed Drug Register who collected prescriptions for pregabalin or gabapentin between 2006 and 2013. The researchers included patients aged 15 years and older in their analyses.
They examined suicidal behavior, unintentional overdoses, head or body injuries, road traffic incidents and offenses, and arrests for violent crime using the Swedish Patient Register and the National Crime Register. In addition, they defined suicidal behavior as emergency hospital visits attributable to self-injurious behavior or suicide attempt, or death by suicide. Unintentional overdoses were defined as emergency hospital visits or death attributable to poisoning by illicit drugs, medications, or biologic substances; accidental poisoning by noxious substances; or acute intoxications and overdoses by alcohol and illicit drugs, excluding intentional self-poisoning, wrote Dr. Molero, who is affiliated with the Karolinska Institute in Stockholm, and her associates.
Of the nearly 192,000 participants who collected prescriptions of gabapentinoids on at least two consecutive occasions, 120,664 received pregabalin, and 85,360 received gabapentin; 14,051 of the participants received both drugs. Fifty-nine percent were women, and most patients were aged 45 or older.
During the study period, 10,026 participants (5.2%) were treated for suicidal behavior or died from suicide, 17,144 participants (8.9%) experienced an unintentional overdose, and 12,070 participants (6.3%) had a road traffic incident or offense. In addition, 70,522 participants (36.7%) had head or body injuries, and 7,984 participants (4.1%) were arrested for a violent crime.