Botulinum toxin treatment failures in cervical dystonia: causes, management, and outcomes.
Botulinum toxin (BoNT) is highly effective in the treatment of cervical dystonia (CD), yet a significant proportion of patients report low levels of satisfaction following treatment and fail to follow up for repeated treatments. The goal of this study was to determine the reasons that some patients have unsatisfactory responses. A total of 35 subjects who came to our center requesting alternative treatments due to unsatisfactory responses following BoNT treatment for CD were evaluated. Included were 26 women and 9 men with an average age of 57.1 years (range 25-82 years), and an average duration of illness of 12.5 years (range 1-55 years). Details of unsatisfactory BoNT treatments were methodically collected by a movement specialist using a standardized intake form, including provider subspecialty, product used, the number of satisfactory or unsatisfactory trials, doses given, specific muscles treated, the use of electromyographic guidance, side effects, and tests of resistance. The specialist then provided repeat treatments if indicated, and followed each case until the reasons for unsatisfactory outcomes could be determined. Multiple reasons for unsatisfactory outcomes were found. They included suboptimal BoNT doses, suboptimal muscle targeting, intolerable side effects, complex movement patterns, discordant perceptions, and incorrect diagnoses. Only one patient was functionally resistant to BoNT. Of 32 subjects who received repeat BoNT treatments, 25 (78 %) achieved satisfactory responses after revision of the original treatment plan. These results indicate that the majority of unsatisfactory responses to BoNT treatment of CD were caused by correctible factors and imply a need for improved education regarding optimal treatment methods.
Departments of Neurology, Human Genetics and Pediatrics, Emory University, Suite 6300 Woodruff Memorial Building, 101 Woodruff Circle, Atlanta, GA, 30322, USA. hjinnah@emory.edu.
H A
HA
Jinnah
Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
Emily
E
Goodmann
Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
Ami R
AR
Rosen
Department of Neurology, Emory University, Atlanta, GA, 30322, USA.|Department of Neurology, Department of Veterans Affairs Medical Center, Atlanta, GA, 30322, USA.
Marian
M
Evatt
Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
Alan
A
Freeman
Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
Stewart
S
Factor
D065087:Acetylcholine Release Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019274:Botulinum Toxins, Type A / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011446:Prospective Studies; D014103:Torticollis / Q000188:drug therapy* / Q000523:psychology; D017211:Treatment Failure
D065087:Acetylcholine Release Inhibitors; D019274:Botulinum Toxins, Type A
Botulinum toxin; Treatment failure; Treatment resistance