It has been consistently reported in the literature that women are more frequently affected by FMD, representing 60–75% of patients.40 Our cohort was consistent with these data. From all 355 participants, 258 (72.7%) were female. More research is needed to understand this gender disparity. In addition to physiological differences, some have suggested that greater exposure to social and environmental risk, such as physical and sexual abuse in women, may account for at least some of the difference.41 Another potential explanatory factor is the finding that women are more likely than men to present to health services by a factor of 1.5–1.40
With regards to ethnic representation, we collected data following the Office for National Statistics ethnic group classifications; see Table 7 for the ethnicity breakdown. Compared to the census data, the Physio4FMD cohort is skewed towards ethnically white people, with under-representation from those identifying as ethnically Asian in particular.
| Ethnicity | Physio4FMD, total cohort (%) | Physio4FMD English cohort (%) | Physio4FMD Scottish cohort (%) | England and Wales census 202142 (%) | Scotland census 201143 (%) |
|---|---|---|---|---|---|
| White | 318 (89.6) | 242 (89.0) | 76 (91.6) | 81.7 | 96.0 |
| Black | 10 (2.8) | 9 (3.3) | 1 (1.2) | 4.0 | > 1.0 |
| Asian | 12 (3.4) | 11 (4) | 1 (1.2) | 9.3 | 2.7 |
| Mixed | 12 (3.4) | 9 (3.3) | 3 (3.6) | 2.9 | < 1.0 |
| Other | 3 (0.8) | 1 (0.4) | 2 (2.4) | 2.1 |
The under-representation of ethnic minorities is an important finding to consider. A likely contributing factor is the exclusion of people who could not understand English sufficiently to complete the study questionnaires independently, which will disproportionally affect people from minority ethnic backgrounds. However, under-representation may have occurred due to any number of reasons and at any stage in the chain of events leading to recruitment, including referral to neurology from primary care.
An unresolved question to consider is, does the incidence of FMD differ across cultures and ethnicities? While we lack good data on this topic, we know that FMD is reported in studies from geographically diverse locations, including Sudan, Pakistan, Turkey, Iran and China, showing similar symptom phenomenology to European and North American cohorts.44,45 There may be cultural differences in the prevalence of certain symptom phenotypes, but, overall, the demographic profile is thought to be consistent across cultures.46 A study by Wilkins et al. 2018 looked at 1961 consecutive admissions to a stroke service at a large general hospital in Qatar and reported the proportion of functional stroke mimic (patients presenting with stroke-like symptoms before being diagnosed with FND) by ethnicity.47 People of South Asian nationality (India, Bangladesh, Nepal, Pakistan and Sri Lanka) had the lowest proportion of functional stroke mimic (5.2% of admissions), compared to people from Western nations (6%), the Far East (6.3%), people from Qatar (7.9%), people from Arab nations (15.6%) and people from Africa (16.8%). The ethnic differences were thought to be related to a complex mixture of economic, social and cultural factors. In particular, the South Asian population in Qatar are composed of expatriates, and the majority are economically disadvantaged, have precarious employment, no family support and inadequate health insurance. Cultural influences may include heightened stigma around mental illness and preferences for traditional therapies. Barriers to recruiting ethnic minorities to mental health research have been explored and include the explanatory model of illness, language barriers, religious beliefs, trust, stigma and gender-related issues.48
Regardless of the cause, the low numbers of people from ethnic minority backgrounds is a limitation of the generalisability of the trial outcomes. Further research is recommended to explore how ethnic and cultural identity may impact the lived experience of FMD and how treatment should be adjusted to accommodate. Future work should include culture-specific co-design of interventions with SUs. Future trials should consider evidence-based strategies to improve recruitment of people from minority ethnic backgrounds.48
When designing this research, a number of choices were made to minimise barriers to inclusion. These were supported options for completing outcome measures for people with difficulty reading and filling in forms, flexibility in scheduling physiotherapy sessions to accommodate employment and child care, and reimbursement of travel costs to minimise the financial burden. A key motivating factor for this research was the inequality of care received by people with FND compared to other physical and mental health conditions. The findings of this research show that physiotherapy was safe and that both randomised groups improved, which makes exclusion of FND from rehabilitation services difficult to justify.