(282) Reason for gabapentinoids prescribing in pregnancy: results from five European countries. A contribution from the IMI ConcePTION project

Background: Assessing indications for use in healthcare data sources is complex due to unstructured prescribing information. In pregnancy drug safety studies, distinguishing medication effects from maternal disease effects is important, as they may carry distinct risks to the pregnancy and fetus/newborn, independent of medications dispensed. Recent years have seen a rise in gabapentinoid (gabapentin and pregabalin) dispensing, possibly due to their diverse indications and potential for misuse.

Objectives: To identify potential indications for prescribing gabapentinoids, as documented in healthcare data sources.

Methods: The study was conducted in Finland, France (Haute-Garonne), Italy (Emilia Romagna), Norway, and Spain (Valencian Region), covering pregnancies from 2006 to 2020. All data sources were mapped to the ConcePTION Common Data Model and common analytic codes were executed locally. Approved indications for gabapentinoids by the European Medicines Agency (epilepsy, neuropathic pain and generalized anxiety disorder) were considered as licensed indications. Algorithms were developed to detect the indications using markers ± one year around the gabapentinoid prescribing: prescriber specialty, primary and specialized care diagnoses, emergency visits, and prescribed/dispensed medicines. Additional analyses investigated potential off-label uses (such as fibromyalgia, restless legs syndrome, bipolar disorder) and misuse (using codes for alcohol withdrawal and substance use disorders).

Results: From one year before pregnancy until childbirth, 2406 pregnancies in Finnish data, 269 in French, 1088 in Italian, 3163 in Norwegian and 743 pregnancies in Spanish data were exposed to gabapentinoids. The indication was undetermined in 36% of Finnish, 39% French, 59% Italian, 12% Norwegian and 25% Spanish pregnancies, and more than one indication was documented in 22% of Finnish, 17% French, 12% Italian, 42% Norwegian and 33% Spanish pregnancies. Epilepsy was the least frequent indication across all data sources (below 15 %). Anxiety was the most common indication in Finnish (42 %), Italian (25%) and Spanish (55%) data, while neuropathic pain led in French (50%) and Norwegian (77%) data. Nevertheless, differences per medications were noted. Additional analyses indicated potential off-label use and misuse, reaching 13% for off-label use in Spain and 16% for potential misuses in Finland.

Conclusions: These results demonstrate the challenge of distinguishing true indication for use in large administrative healthcare data. Nevertheless, findings show that gabapentin and pregabalin are commonly prescribed for indication other than epilepsy.