TY - JOUR
T1 - Capillary blood sampling for the determination of clozapine concentrations
T2 - analytical validation and patient experience
AU - Breken, B.D.
AU - Grootens, K.P.
AU - Vermeulen Windsant-van den Tweel, A.M.
AU - Hermens, W.A.
AU - Derijks, H.J.
N1 - Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.
PY - 2024
Y1 - 2024
N2 - Patients may be reluctant to start clozapine (CLZ) because of the frequent blood sampling needed for white blood cell monitoring, but also therapeutic drug monitoring of CLZ. Finger prick, instead of venepuncture, might lower the threshold to CLZ use. The aim of this study was to determine whether CLZ concentrations are the same in capillary and venous blood samples. Capillary blood was drawn by finger prick and collected in the Hem-Col tube. Paired capillary and venous blood samples were collected from inpatients and outpatients of a mental health institute. Patients were asked to rate pain, experience, and preference for blood sampling method. Passing-Bablok analysis of 40 paired samples showed that CLZ concentrations were statistically equal in capillary and venous samples {slope 0.96 [95% confidence interval (CI): 0.88-1.04], intercept -6.86 (95% CI: -30.75 to 24.13)}. Venepuncture was the preferred method based on the experience ( P = 0.009) and preference ( P = 0.043) items. In conclusion, CLZ concentrations were similar in venous and capillary blood samples. Venepuncture appeared to be preferred to finger prick for blood sampling. Our results emphasize the importance of consulting patients' individual preference for blood sampling method.
AB - Patients may be reluctant to start clozapine (CLZ) because of the frequent blood sampling needed for white blood cell monitoring, but also therapeutic drug monitoring of CLZ. Finger prick, instead of venepuncture, might lower the threshold to CLZ use. The aim of this study was to determine whether CLZ concentrations are the same in capillary and venous blood samples. Capillary blood was drawn by finger prick and collected in the Hem-Col tube. Paired capillary and venous blood samples were collected from inpatients and outpatients of a mental health institute. Patients were asked to rate pain, experience, and preference for blood sampling method. Passing-Bablok analysis of 40 paired samples showed that CLZ concentrations were statistically equal in capillary and venous samples {slope 0.96 [95% confidence interval (CI): 0.88-1.04], intercept -6.86 (95% CI: -30.75 to 24.13)}. Venepuncture was the preferred method based on the experience ( P = 0.009) and preference ( P = 0.043) items. In conclusion, CLZ concentrations were similar in venous and capillary blood samples. Venepuncture appeared to be preferred to finger prick for blood sampling. Our results emphasize the importance of consulting patients' individual preference for blood sampling method.
KW - Humans
KW - Clozapine/therapeutic use
KW - Blood Specimen Collection/methods
KW - Drug Monitoring/methods
KW - Capillaries
KW - Patient Outcome Assessment
UR - http://www.scopus.com/inward/record.url?scp=85178499836&partnerID=8YFLogxK
U2 - 10.1097/YIC.0000000000000494
DO - 10.1097/YIC.0000000000000494
M3 - Article
C2 - 37551596
SN - 0268-1315
VL - 39
SP - 23
EP - 28
JO - International Clinical Psychopharmacology
JF - International Clinical Psychopharmacology
IS - 1
ER -