Headache, opiate use, and prescribing trends in women with idiopathic intracranial hypertension: a population-based matched cohort study

Background and objectives: Physician prescribing habits for opiates and headache therapies have not been previously evaluated in a large, matched cohort study in idiopathic intracranial hypertension (IIH). Our objective was to evaluate opiate and headache medication prescribing habits in women with IIH compared to matched women with migraine and population controls. We also investigated the occurrence of new onset headache in IIH compared to population controls.

Methods: We performed a population-based matched, retrospective cohort study to explore headache outcomes. Cross-sectional analyses were used to describe medication prescribing patterns. We used data from IQVIA Medical Research Data, an anonymized, nationally representative primary care electronic medical records database in the United Kingdom, from 1st January 1995 to 25th September 2019. Women aged ≥16 years were eligible for inclusion. Women with IIH (exposure) were matched by age and body mass index with up to 10 control women without IIH but with migraine (migraine controls), and without IIH or migraine (population controls).

Results: 3411 women with IIH, 13,966 migraine controls and 33,495 population controls were included. The adjusted hazard ratio (aHR) for new onset headache in IIH compared to population controls was 3.09 (95%CI 2.78-3.43). In the first year after diagnosis, 58% of women with IIH were prescribed acetazolamide and 20% topiramate. 20% of women with IIH were prescribed opiates within the first year of their diagnosis, reducing to 17% after six years, compared to 8% and 11% among those with migraine, respectively. Twice as many women with IIH were prescribed opiates compared to migraine controls and three times as many women with IIH were prescribed opiates compared to population controls. Women with IIH were also prescribed more headache preventative medications compared to migraine controls.

Discussion: Women with IIH were more likely to be prescribed opiate and simple analgesics compared to both migraine and population controls. Women with IIH trialled more preventative medications over their disease course suggesting that headaches in IIH may be more refractory to treatment.