Article

OBJECTIVE: To examine adherence to baclofen, tizanidine, and dantrolene (U.S.
Food and Drug Administration-approved oral spasticity medications), and
identified determinants of adherence. DESIGN: A retrospective administrative
claims data analysis that used medical and pharmacy claims data and enrollment
information from a large, national U.S. health plan. METHODS: The
subjects were commercial health plan members who initiated treatment on baclofen,
tizanidine, or dantrolene from January 1, 2004, through September 30, 2009, and
who had stroke, spinal cord injury, traumatic brain injury, cerebral palsy, or
multiple sclerosis. Descriptive and logistic regression statistical analyses were
performed. MAIN OUTCOME MEASUREMENTS: Outcomes were adherence, measured as
continuous medication possession ratio (MPR) and as a binary indicator (MPR
>/=0.80, adherent; MPR <0.80, nonadherent), change in oral spasticity medication,
and use of nonoral spasticity therapy. RESULTS: The study population included
2840 subjects. Adherence overall was poor: the range of mean unadjusted MPR
values was 0.10-0.50, which indicated that, at best, the subjects were adherent
to their index spasticity medications for 50% of their treatment periods.
Unadjusted overall MPRs for baclofen and tizanidine were 20.4% and 9.1%,
respectively. Fewer than 5% of subjects changed oral spasticity medications. The
results of logistic regression to identify determinants of adherence showed that
subjects treated with tizanidine versus baclofen had 37.4% lower odds of
adherence and that subjects with traumatic brain injury versus stroke had 77.5%
lower odds of adherence. The odds of adherence increased with age and with
preindex contracture or decubitus ulcer. CONCLUSIONS: Adherence to oral
spasticity medication was poor irrespective of index spasticity medication or
condition. Results from this study indicated that physicians cannot assume that
patients are adherent to prescribed oral spasticity medications. A more complete
understanding of the reasons behind nonadherence is required.
CI - Copyright (c) 2013 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS