Core Outcome Set Aims to Improve Quality of Life in Drug-Resistant Epilepsy

A core outcome set for QOL in adults with drug-resistant epilepsy has been defined and highlights factors outside of seizure frequency and severity that impact QOL in epilepsy.

The first core outcome set (COS) for quality of life (QOL) measures in the setting of adult drug-resistant epilepsy has been defined in a study published in the journal Epilepsia.

Epilepsy is a common neurological disorder marked by seizure and associated with morbidity and decreased QOL. Mounting evidence suggests that QOL is affected not only by seizure frequency and medication side effects, but also by cognition, physical challenges, job and school performance, and stigma associated with the condition.

For the study, researchers from the University of California, San Francisco defined COS for QOL measures in treatment-resistant epilepsy. To do so, they identified important QOL outcomes sourced from 9 QOL instruments recommended by the American Academy of Neurology (AAN) in 2017, identified gaps in existing scales by discussing unmet needs with patients and caregivers in focus groups, rated the importance of these outcomes using a Delphi survey approach, and came to a group consensus about the COS.

After review of the existing QOL instruments and patient and caregiver focus groups, a total of 78 candidate QOL outcomes were formulated. These candidates included new items (n=5) which involved wearable technologies and implanted devices.

Nearly 90% of the issues identified as core QOL outcomes pertained to areas outside of seizure frequency and severity, indicating that the impact of epilepsy extends well beyond its most obvious manifestation.

In the Delphi survey, 95 patients and 14 caregivers participated in round 1 and 43 patients and 12 caregivers in round 2, respectively. The majority of patients reported having weekly or monthly seizures.

Patients and caregivers selected which QOL outcomes they thought were critically important. The selected outcomes were highly correlated between patient and caregiver in both rounds (r range, 0.49-0.63; both P <.001). Similarly, the items selected as not important were correlated (r range, 0.56-0.60; both P <.001).

Overall, the study identified 41 critical COS QOL outcomes. After review by clinicians, redundant items were removed and a final set of 36 items were selected as the COS.

The COS QOL measures involved:

  • seizure-related items (how often do seizures occur, how long do seizures last, are seizures unexpected),
  • cognitive-related items (are you able to focus, do you make speech errors, do you have brain fog),
  • mental health-related items (do you feel anxiety, how is your mental health, do your antiseizure medications affect your mood), and
  • QOL-related items (can you drive, do you feel physically tired, do you have concerns about your future).

To facilitate the use of these COS in clinical practice, the researchers provided a list of 11 domains that clinicians should address during patient interactions, including:

  • seizure burden,
  • seizure unpredictability,
  • seizure types,
  • cognition,
  • mental health,
  • medication side effects,
  • driving privileges,
  • family impact,
  • concerns about the future,
  • sleep, and
  • overall QOL.

The formulation of this COS of QOL outcomes may have been limited as the COVID-19 pandemic prohibited focus groups from being conducted in person.

The researchers concluded, “This study is, to our knowledge, the first to define a COS for QOL measurement in adults with drug-resistant epilepsy. […] Nearly 90% of the issues identified as core QOL outcomes pertained to areas outside of seizure frequency and severity, indicating that the impact of epilepsy extends well beyond its most obvious manifestation.”

Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.


Chiang S, Moss R, Stern JM, et al. Development of a core outcome set for quality of life for adults with drug-resistant epilepsy: a multistakeholder Delphi consensus study. Epilepsia. Published online November 8, 2022. doi:10.1111/epi.17461