Exploration of primary hypothyroidism laboratory monitoring and patient experience: finding new ways clinical laboratories could aid management of a common chronic disease

Abstract

BACKGROUND: Primary hypothyroidism is a common condition with significant morbidity and mortality. It requires lifelong thyroid hormone replacement and NICE NG145 recommends levothyroxine as a first-line treatment. The aim is to return patients to a euthyroid state defined as the maintenance of TSH within the population reference range. Annual monitoring of thyroid function helps prevent over or under treatment based on TSH concentration and highlights when dosage adjustments may be required: evidence suggests testing intervals are not reliably maintained and that patient experience can be suboptimal. The aim of this project was to investigate whether a novel digital system could be implemented to aid patient self-management of primary hypothyroidism. METHODOLOGY: This research project is composed of three studies including investigation of thyroid function test requesting patterns by primary care practices in Wolverhampton and comparison of capillary serum and plasma to venous serum for monitoring thyroid function. In the final study fourteen focus group interviews with 55 patients living with primary hypothyroidism were undertaken to explore patient experiences and perceptions regarding remote sample collection and self-management of primary hypothyroidism and the barriers and facilitators to implementation of a digital system for direct to patient results reporting and primary hypothyroidism management. RESULTS: In study 1, approximately half of the local population had at least one TFT between 2020 and 2023, only 7.6% of patients first requests listed levothyroxine treatment. Median retesting interval for follow up TFT was 293 days (IQR 161 to 404), average 296 days, for patients taking levothyroxine. Study 2 showed TSH in capillary serum and capillary plasma was comparable to venous serum. All capillary blood TSH results were within maximum permitted difference (50.25%) from target venous TSH but collection of capillary blood using Sarstedt safety lancet (Super, penetration depth: 1.6 mm) required development of defined collection techniques to ensure adequate sample volume was collected. Three themes were developed by reflexive thematic analysis of focus group interview transcripts with 55 patients from across the UK in the final study. The three themes were “Do GPs care about hypothyroidism?”, “losing faith; taking control” and “Patient knowledge & self-management”. DISCUSSION The evidence generated in this mixed methods study did not support the implementation of new digital system to aid patient self-management of primary hypothyroidism. Instead better application of existing care models and resources should be prioritised, such as improved NHS app functionality, better thyroid function test scheduling and improved patient and healthcare professional interactions to enhance patient experience with respect to primary hypothyroidism.

Date of Award	21 Jan 2025
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Lucie Byrne-Davis (Main Supervisor)