Key findings
The current study aimed to determine the true contribution of FaCE subscales to overall facial palsy-specific quality of life. According to our findings, social well-being and synkinesis are the most relevant components of ‘overall’ facial palsy-related quality of life. Both constructs are currently underestimated in the calculation of the FaCE total score.
Our analysis shows that the social burden patients experience is the most important component of ‘overall’ quality of life and is underestimated in the FaCE total score. Our results suggest that almost half of ‘overall’ facial palsy-related quality of life is socially related. With this, our findings more closely reflect a different facial palsy PROM: the Facial Disability Index (FDI), which consists of 10 questions evenly split between the physical and social domain.
Synkinesis, which is described in the facial comfort subscale, was found to be the second most important component of ‘overall’ facial palsy-related quality of life, and the only other statistically significantly contributing subscale. In a previous study, synkinesis was found to contribute significantly to the prediction of quality of life.3 A high degree of synkinesis was also found to be associated with “non-effective” self-reported emotional expression.4 Synkinesis may thus reduce quality of life by both causing physical discomfort and impairing social function, and it should form a larger component of facial palsy-specific quality of life assessment.
Surprisingly, eye comfort and lacrimal control were insignificant predictors of overall quality of life. This is in line with previous research suggesting that periocular muscle function is of low importance in estimating quality of life.5 However, this is not in line with our clinical expertise or the findings of other researchers that the treatment of periocular complaints leads to a significant improvement in total FaCE score.6 A possible explanation for this could be that most patients in our sample already received periocular treatment, and therefore no longer experience periocular problems. This is especially plausible in our sample of chronic facial palsy patients but requires further investigation.