Gabapentinoid users increased from 4.0% in 2015 to 4.7% in 2021, Medical Expenditure Panel Survey (MEPS) data showed.
Moreover, gabapentinoids -- which includes gabapentin and pregabalin -- continued to be used for chronic pain and in conjunction with other sedating medications, reported Michael Johansen, MD, MS, of OhioHealth in Columbus, and Donovan Maust, MD, MS, of the University of Michigan in Ann Arbor.
"Our descriptive analysis of gabapentinoid use in the United States showed a continued increase since our using MEPS data up to 2015," Johansen and Maust wrote in . "The growth was primarily driven by gabapentin, as we did not detect any increase in pregabalin users after 2008 or after generic availability in 2019."
The findings "are troublesome," noted Christopher Goodman, MD, of the University of South Carolina School of Medicine in Columbia, who wasn't involved with the research.
"Gabapentinoid use continues to rise, increasingly co-administered with other sedatives, despite limited evidence to support their use and potential for harm," Goodman told MedPage Today.
"Regulators and policymakers may need to consider action to curb this trend," he continued. "In my view, the growth of these medications represents the poor quality of chronic pain management in the U.S."
Gabapentin is approved for ; gabapentin enacarbil is approved for . Despite limited indications, gabapentin and pregabalin are for various other pain syndromes.
Common side effects of gabapentinoids include drowsiness, dizziness, blurry or double vision, or difficulty with coordination and concentration. In 2019, the FDA warned about serious breathing problems that may occur in patients using gabapentin or pregabalin who have respiratory risk factors. These factors included taking opioids or other drugs that depress the central nervous system (CNS), conditions like chronic obstructive pulmonary disease (COPD) that reduce lung function, or older age.
Johansen and Maust used cross-sectional and longitudinal data from the 2002-2021 Department of Health and Human Services . Gabapentinoid users were identified as someone who reported a prescription fill of any gabapentinoid during a year.
Cross-sectional data included 488,348 people. Among them, gabapentinoid use increased from 1.2% in 2002 to 4.0% in 2015, and to 4.7% in 2021 (P<0.01). Use of gabapentin (Neurontin and other drugs, including generics) rose throughout the study, while pregabalin use was largely unchanged after 2008.
The probability of gabapentinoid use increased with age: between 2019 and 2021, it was about 9% among people 70 and older. In 2017-2021, musculoskeletal pain (1.5%) and diabetes (1.6%) were the medical conditions with the highest proportion of the population using gabapentinoids. Those proportions were smaller for polyneuropathies (0.8%) and fibromyalgia (0.9%), though polyneuropathies and fibromyalgia had the highest odds ratio of use.
The researchers also assessed other medication classes that acted on the CNS including opioids, muscle relaxants, benzodiazepines, serotonin and norephinephine re-uptake inhibitors, and tricyclic antidepressants. As the number of CNS-active medication classes rose, so did gabapentinoid use. "Gabapentinoid use was much more likely among individuals who used other medications used in chronic pain," Johansen and Maust observed.
Longitudinal data included 196,589 people tracked over time. Between 2011-2012 and 2017-2018, new gabapentinoid users outnumbered gabapentinoid stoppers, but the difference between starters and stoppers was smaller in 2018-2019 and 2019-2021.
The study has several limitations including changes in survey design in 2020 due to the pandemic and possible under-reporting of short-term opioid and muscle relaxants, the researchers acknowledged. The analysis couldn't directly link medical conditions to a gabapentinoid and surveys couldn't determine whether medication use was synchronous or asynchronous throughout a year.
"Gabapentinoid users continued to increase following our 2015 publication despite a dearth of evidence supporting use in many cases; while these clinical scenarios can be challenging, continuation should be reconsidered at regular intervals," Johansen and Maust wrote.
Disclosures
Maust reported funding from the National Institutes of Health. No other disclosures were reported.
Primary Source
Annals of Family Medicine
Johansen ME, Maust DT "Update to gabapentinoid use in the United States, 2002-2021" Ann Fam Med 2024; DOI: 10.1370/afm.3052.