Pharmacist-led thyroid point-of-care testing

Abstract

Early detection of thyroid dysfunction through point-of-care testing (POCT) is relevant for high-risk individuals and those previously diagnosed who may remain uncontrolled due to inadequate adherence or suboptimal dosing. Establishing pharmacist-led thyroid POCT enables timely screening and ongoing monitoring, enhancing long-term care. The aim was to develop a framework for pharmacist-led thyroid POCT and assess feasibility of implementation in a community pharmacy setting. Appraisal of thyroid POCT devices was conducted taking into consideration technical and analytical specifications, cost and accessibility. A POCT device was selected and validated by comparing POCT results to laboratory-based results for 20 participants attending a physician clinic for routine thyroid function testing, recruited by convenience sampling. A framework for pharmacist-led thyroid POCT was developed and validated by an expert panel. The developed framework consists of a Data Collection Tool to assess hypothyroidism risk factors, health status, knowledge on thyroid function testing and medication adherence; a standard operating procedure for performing POCT; an Action Plan for standardised and personalised patient actioning based on test results including physician referral as necessary; and a Patient Education Resource providing information related to hypothyroidism management. The framework was tested for feasibility in 75 participants recruited by convenience sampling from a community pharmacy according to inclusion and exclusion criteria: taking levothyroxine or medication/s which may affect thyroid function, no thyroid function testing in past 6 months, no acute illness, not pregnant or breastfeeding. Descriptive statistics were performed (p<0.05 statistically significant). Fourteen thyroid POCT devices were compared, where two were found to be available locally. Following appraisal of devices, AcroBiotech Inc. Thyroid-stimulating hormone (TSH) rapid test cassette which screens for hypothyroidism was selected for use in this study (CE-marked, qualitative chromatographic immunoassay, sensitivity 5μIU/mL, specimen volume 50μL fingerstick blood, time for result 10 minutes). Validation of the selected POCT device revealed 95% concordance with laboratory-based results (κ=0.773), supporting device clinical reliability. The 75 participants for feasibility testing of the framework (female n=57; mode age range 45–54 years n=24), were taking levothyroxine (n=45) or medication/s that may affect thyroid function (n=30). Twentythree participants had a positive result (TSH ≥5 μIU/mL) indicating hypothyroidism; of whom 15 were being treated for hypothyroidism, indicating inadequate adherence to levothyroxine (n=12) or dosage insufficiency (n=3), while 8 were taking medication/s which may affect thyroid function (newly identified). All participants with a positive TSH result were referred for physician assessment. Thirty-one participants reported two or more symptoms indicative of hypothyroidism and were referred for physician assessment. From the 45 participants taking levothyroxine, 44 were provided with the Patient Education Resource. A statistically significant association was observed between positive TSH result, symptoms of hypothyroidism, and incorrect levothyroxine use (p<0.05). This study identified a clinically reliable POCT device which screens for hypothyroidism and presents a validated pharmacist-led framework which is feasible to be implemented in community pharmacy to support patient screening and monitoring within a collaborative care model.