Patient adherence to transdermal rivastigmine after switching from oral donepezil: a retrospective claims database study.
OBJECTIVE
To examine patient adherence before and after switching from donepezil to the rivastigmine patch.


METHODS
This retrospective cohort study used the MarketScan Commercial and Medicare data sets (2004 to 2009). Patients with a diagnosis of Alzheimer disease who were new donepezil users and were subsequently switched to the rivastigmine patch were included. The proportion of days covered (PDC) and PDC difference between donepezil and the rivastigmine patch were calculated from the time of initiation to the switch, capped at 1 year after the first respective claim. PDC was calculated as the number of days with drugs available divided by the number of days in the respective follow-up periods.


RESULTS
The sample included 772 patients (mean age 77 y; 58% female). The mean time between switching from donepezil to the rivastigmine patch was 579 (SD=317.3) days. The mean PDC for the rivastigmine patch was highest among patients who switched within 3 months (80.4% vs. 90.7%; P=0.04) and within 7 to 9 months (61.3% vs. 71.0%; P=0.05) of initiating donepezil. When adherence was analyzed in increments of 1 year, patients who switched to the rivastigmine patch within the first year of treatment had significantly greater adherence to rivastigmine compared with those who were on donepezil (PDC 69.3% vs. 60.6%; P=0.0004).


CONCLUSIONS
Switching from donepezil to the rivastigmine patch seems to be associated with increased adherence, especially in patients who switched within the first year of initiating donepezil.
Health Economics & Outcomes Research, Novartis Pharmaceuticals Corporation, East Hanover, NJ 07936-1080, USA.
Haijun
H
Tian
Safiya
S
Abouzaid
Wei
W
Chen
Kristijan H
KH
Kahler
Edward
E
Kim
D000368:Aged; D000544:Alzheimer Disease / Q000188:drug therapy*; D002800:Cholinesterase Inhibitors / Q000008:administration & dosage*; D015331:Cohort Studies; D000077265:Donepezil; D005260:Female; D006801:Humans; D007189:Indans / Q000627:therapeutic use; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*; D048448:Phenylcarbamates / Q000008:administration & dosage*; D010880:Piperidines / Q000627:therapeutic use; D012189:Retrospective Studies; D000068836:Rivastigmine; D057968:Transdermal Patch
D002800:Cholinesterase Inhibitors; D007189:Indans; D048448:Phenylcarbamates; D010880:Piperidines; D000077265:Donepezil; D000068836:Rivastigmine