Potentially unintended discontinuation of medication following hospitalisation: a retrospective cohort study

Study type
Protocol
Date of Approval
Study reference ID
19_126
Lay Summary

Older people are more likely to be prescribed multiple medications, have multiple chronic conditions and experience an increasing number of transitions of care (e.g. hospitalisation). Polypharmacy (the prescribing of multiple medications) is increasingly common and patients are now routinely prescribed medication long term for the management of chronic conditions (e.g. thyroxine in under active thyroid disease). In the UK, General Practitioners usually coordinate the prescribing of patients' medications.

Previous studies have reported that poor coordination of transitions of care may lead to medication errors and potentially adverse drug events. In particular, it is known that discharge communications following hospitalisation commonly omit appropriate medications unintentionally.

It is not clear how these transitions of care and potential for unintentional omissions impacts on prescribing in the GP record. The aim of this study is to examine the GP and hospitalisation records of older patients prescribed specific medications long term and determine the impact of hospitalisation on their continuity in the GP record.

Technical Summary

Background:
Previous studies have reported an increased risk of medication discontinuity post hospitalisation. These studies have primarily examined large dispensing and/or administrative databases post hospitalisation to record the outcome of 'discontinuity'. There has been limited specialised study of the impact of hospitalisation and/or medication error at hospital discharge propagating forward into general practice prescribing records.

Objectives:
To determine whether the unintended discontinuation of specific common, evidence based, long-term medication occurs after hospitalisation; what factors are associated with unintended discontinuation.

Design:
A retrospective cohort study utilising Hospital Episodes Statistics and CPRD. A multi-level logistic regression analysis examining the association between discontinuity and hospitalisation comparing those experiencing hospitalisation and those not hospitalised.

Primary and secondary outcomes:
Discontinuity of four evidence-based medication drug classes- antithrombotic, lipid-lowering, thyroid replacement drugs and respiratory inhalers in hospitalised versus non-hospitalised patients; patient and health system factors associated with discontinuity.

Health Outcomes to be Measured

Failure to renew specified medications (as defined by the absence of the specified medication in the GP prescribing record in the 90 days post hospitalisation/index date)

Collaborators

Patrick Redmond - Chief Investigator - King's College London (KCL)
Patrick Redmond - Corresponding Applicant - King's College London (KCL)
Mariam Molokhia - Collaborator - King's College London (KCL)
Martin Gulliford - Collaborator - King's College London (KCL)
Vibhore Prasad - Collaborator - King's College London (KCL)

Linkages

HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation