Purpose:
It is important for clinicians to demonstrate that patients are helped by the interventions they perform. Several questionnaire-based tools have been developed to measure patient-reported benefit from botulinum toxin (BTX) for essential blepharospasm. We compared two of these methods which measure slightly different aspects of outcome; the Glasgow benefit inventory (GBI), a post-interventional quality-of-life scale, and the Blepharospasm Disability Index (BSDI), which compares functional ability before and after treatment. We also wanted to compare our findings with previously published results using the GBI.
Methods:
A cross-sectional study of 61 consecutive patients treated with BTX for blepharospasm. The GBI generates a score from -100 (maximum harm) through 0 (no effect) to +100 (maximum benefit). The BSDI compares changes in function before and after BTX treatment on a scale of -4 (maximum harm) through 0 (no effect) to +4 (maximum benefit).
Results:
Both the GBI and BSDI showed a statistically-significant benefit from treatment at +31.09 (95% CI = 25.67-36.52, p<0.001) and +1.13 (95% CI = 0.92-1.34, p<0.001) respectively. Linear regression analysis (Figure 1) showed a strong positive correlation between the two scoring systems (r=0.56).
Conclusions:
BTX treatment for blepharospasm is associated with significant patient-reported improvements in quality-of-life (GBI) and functional ability (BSDI). Although a good correlation is demonstrated between these two measures of benefit, they record different aspects of outcome, and we would recommend that both assessments be used together. Most patients found the questionnaires straightforward to complete, and the majority were able to finish both in under ten minutes during a telephone interview. Our results using the GBI were similar to previously published findings (+29.20, MacAndie & Kemp, 2004).
Keywords: eyelid • quality of life • clinical (human) or epidemiologic studies: outcomes/complications