Prognostic factors for chronic headache – a systematic review Can we identify factors predicting prognosis and influencing response to preventive interventions for chronic headache?
Problem
A wide range of demographic, clinical, psychological and social factors may affect prognosis and treatment outcome for people with chronic headache. Our aims were to identify predictors of prognosis and trial outcomes in prospective studies of people with chronic headache
Approach
A systematic review of published literature in peer-reviewed journals. We included a) randomised controlled trials (RCTs) of interventions for chronic headache that reported subgroup analyses and b) prospective cohort studies, published in English, since 1980. Participants included adults with chronic headache (including: chronic headache, chronic migraine, chronic tension-type headache with or without medication overuse headache respectively).
We searched key databases, two reviewers independently extracted data, assessed the methodological quality of studies and overall quality of evidence identified using appropriate published checklists
Findings
We identified 16556 titles, removed 663 duplicates, and reviewed 233 papers, of which 27 were included in the review - 17 prospective cohorts and 10 RCTs with subgroup analyses reported.
There was moderate quality evidence indicating that depression, anxiety, poor sleep and stress, medication overuse and self-efficacy for managing headaches are potential prognostic factors in chronic headache. There was inconclusive evidence about treatment expectations, age, age at onset, body mass index (BMI), employment and several headache features.
Consequences
This review has identified several potential predictors of poor prognosis and worse outcome post interventions in people with chronic headache. The majority of these are modifiable. The findings also highlight the need for more longitudinal high quality research of prognostic factors in chronic headache