Recruitment of a cohort of lamotrigine users through community pharmacists: differences between patients who gave informed consent and those who did not.
OBJECTIVE
Community pharmacists may function as intermediaries in the recruitment of a population-based cohort of patients using specific drugs. In this study, baseline characteristics and the retention rate of patients that gave informed consent, refused and did not answer were compared.


METHODS
A total of 1819 patients using the new antiepileptic drug (AED) lamotrigine were asked to provide informed consent for a retrospective chart study via their individual pharmacist. Four possible reactions resulted from the consent question: active consent, active refusal, passive refusal and non-informed. Patient characteristics and lamotrigine retention rate of the different groups were compared.


RESULTS
Pharmacists did not inform a total of 183 patients (10%). Of the remaining patients, a total of 968 (59%) gave consent; 101 (6%) actively refused and 567 (35%) did not respond. Age, burden of illness, psychotropic co-medication and continuation of lamotrigine therapy were related to active consent. Lamotrigine retention rate in patients that gave consent was higher than in other patients.


CONCLUSIONS
Patient recruitment with community pharmacists as intermediaries for observational studies on the effects of (new) drugs is feasible, and allows access to a broad population of patients. The recruitment procedure, however, may lead to selection bias.
Knoester
P D
PD
Department of Clinical Pharmacy, University Medical Centre Nijmegen, Nijmegen, The Netherlands. p.knoester@erasmusmc.nl
Belitser
S V
SV
Deckers
C L P
CL
Keyser
A
A
Renier
W O
WO
Egberts
A C G
AC
Hekster
Y A
YA
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000927:Anticonvulsants / Q000008:administration & dosage* / Q000627:therapeutic use; D015331:Cohort Studies; D003157:Community Pharmacy Services; D004827:Epilepsy / Q000188:drug therapy; D005260:Female; D006304:Health Status; D006801:Humans; D007258:Informed Consent; D000077213:Lamotrigine; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D010595:Pharmacists / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D014227:Triazines / Q000008:administration & dosage* / Q000627:therapeutic use
D000927:Anticonvulsants; D014227:Triazines; D000077213:Lamotrigine