Long-term efficacy of botulinum toxin A for treatment of blepharospasm, hemifacial spasm, and spastic entropion: a multicentre study using two drug-dose escalation indexes.
OBJECTIVE
To investigate the long-term effectiveness and safety of botulinum neurotoxin A (BoNT-A) treatment in patients with blepharospasm (BEB), hemifacial spasm (HFS), and entropion (EN) and to use for the first time two modified indexes, 'botulin toxin escalation index-U' (BEI-U) and 'botulin toxin escalation index percentage' (BEI-%), in the dose-escalation evaluation.


METHODS
All patients in this multicentre study were followed for at least 10 years and main outcomes were clinical efficacy, duration of relief, BEI-U and BEI-%, and frequency of adverse events.


RESULTS
BEB, HFS, and EN patients received a mean BoNT-A dose with a significant inter-group difference (P<0.0005, respectively). The mean (+/-SD) effect duration was statistically different (P=0.009) among three patient groups. Regarding the BoNT-A escalation indexes, the mean (+/-SD) values of BEI-U and BEI-% were statistically different (P=0.035 and 0.047, respectively) among the three groups. In BEB patients, the BEI-% was significantly increased in younger compared with older patients (P=0.008). The most frequent adverse events were upper lid ptosis, diplopia, ecchymosis, and localized bruising.


CONCLUSIONS
This long-term multicentre study supports a high efficacy and good safety profile of BoNT-A for treatment of BEB, HFS, and EN. The BEI indexes indicate a significantly greater BoNT-A-dose escalation for BEB patients compared with HFS or EN patients and a significantly greater BEI-% in younger vsolder BEB patients. These results confirm a greater efficacy in the elderly and provide a framework for long-term studies with a more flexible and reliable evaluation of drug-dose escalation.
Cillino
S
S
Dipartimento Universitario di Neuroscienze Cliniche, Sezione di Oftalmologia, Università degli Studi di Palermo, Palermo, Italy. cillino@unipa.it
Raimondi
G
G
Guépratte
N
N
Damiani
S
S
Cillino
M
M
Di Pace
F
F
Casuccio
A
A
D000368:Aged; D000369:Aged, 80 and over; D001764:Blepharospasm / Q000188:drug therapy*; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004774:Entropion / Q000188:drug therapy*; D005260:Female; D005500:Follow-Up Studies; D019569:Hemifacial Spasm / Q000188:drug therapy*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009128:Muscle Spasticity / Q000188:drug therapy*; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000627:therapeutic use*
D004338:Drug Combinations; D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A