Background & Aims: trigeminal neuralgia (TN) is a neuropathic pain disorder causing recurrent and excruciating unilateral electric shock like pains on the anatomical distribution of the trigeminal nerve. There is no cure for TN however, there are many medical and/or surgical treatments available. To date, it has been difficult to compare treatment effectiveness between the different treatments due to the high heterogeneity in outcome assessment. Furthermore, outcomes have traditionally been chosen by clinicians and researchers, and mostly limited to assessment of treatment on pain intensity/relief. Patient’s perspective has not been considered and outcomes other than pain relief/intensity, have often been ignored. The aim of this study was to reach consensus on what outcomes of treatment matter most to different TN stakeholders (patients, clinicians, and researchers) and to aggregate a core outcome set (COS) to be used in all future clinical trials to improve harmonisation of research results to contribute to better quality systematic reviews and meta-analyses and ultimately to improving the quality of care and the lives of those living with TN.
Methods: a list of outcomes scored in a 3-round Delphi survey was presented for discussion during a 3-hour online consensus meeting in April 2022. Researchers and clinicians who completed the 3-round Delphi were randomly selected to participate; a cohort of patients with TN was recruited from a facial pain clinic at a London teaching hospital. Participants were split into two groups and were asked to discuss the outcomes for which no consensus was reached during the Delphi survey, focusing on how important it would be to include them in a COS for TN clinical trials. Subsequently, participants were asked to score the outcomes using a Likert scale from 1-9 (1-3 not important; 4-6 important but not critical; 7-9 critical). Outcomes scored as critical by ≥70% and not important by <15% were retained and added to the list of outcomes which had been selected as critical during the Delphi survey. A final majority vote (i.e., >50%) was held to reduce the COS to a feasible number of outcomes (“important but not critical outcome” and “mandatory outcome to be included in the COS”).
Results: Thirteen participants attended the online consensus meeting (five clinicians, two researchers and six patients). All six patients and three clinicians were from the United Kingdom, two clinicians were from Denmark and Germany respectively, and the two researchers were from Italy and Switzerland, respectively. Of the 23 outcomes presented for discussion and scoring, only two made it to the final list to be considered for inclusion in the TN COS. Of the 19 outcomes which went through a final majority vote, six were deemed “important but not critical” and two reached a tie. Eleven outcomes were deemed “mandatory” to be included in the TN COS - pain relief, duration of pain relief, pain intensity, pain interference, pain free on medication, health related quality of life, ability to participate in social roles and activities, overall response to treatment, satisfaction with treatment, side effects of medication and of surgery.
Conclusions: the finalised TN COS highlights that TN, like many other chronic pains, should be viewed in the context of a biopsychosocial model rather than from a biomedical perspective only. A uniform and systematic use of a COS allows for combination of data from different trials and to draw meaningful conclusions about the effects of treatment. This means that it will be possible to quickly identify treatments that work and to offer them to patients earlier in their journey. The use of a TN COS in clinical trials will provide more standardized data which can be aggregated by systematic reviewers and those conducting meta-analysis. Data can be used to create evidence-based guidelines for the management of TN in clinical practice.
Relevance for Patient Care: TN can be managed by different healthcare professionals (e.g., dentists, neurosurgeons, neurologists, pain specialists, GPs, oral medicine physicians), clinical guidelines will be crucial to allow patients to have access to standardised and universal care, which means that more patients will have access to adequate treatment regardless of their geographical location or clinical care setting.