A retrospective, observational, real world study to describe the treatment pathway, healthcare resource utilisation, and clinical outcomes in patients with metachromatic leukodystrophy

Date of Approval
Application Number
Technical Summary

MLD is a rare genetic disorder which affects the nervous system and shortens life-expectancy. The study will describe a population of patients with an MLD diagnosis recorded on CPRD. The study aims to describe the annual healthcare resource utilisation and costs associated with management of patients with MLD using CPRD (Aurum and Gold) for primary care resources, and HES inpatient, outpatient and A&E data for secondary care resources. Primary care resource analyses will include consultations, prescriptions and laboratory and diagnostic tests. Secondary care resource utilisation will include inpatient (including total admitted time, admissions/bed days), outpatient appointments and A&E. Speciality and elective/non-elective admissions and those to Intensive care and high dependency units, will be reported. Rates will be reported by year pre- and post-diagnosis and by year from diagnosis (including mean, standard deviation/ median, interquartile range, and range). Costing will be based on HES generated Health Resource Group (HRG), including inpatient, outpatient, and A&E tariff costs, and Personal Social Services Research Unit reference costs and the British National Formulary.
In addition, the study population will be described in terms of age at first symptom or diagnosis, sex (mean, SD, median, and ranges), observed survival (overall and from diagnosis by Kaplan Meier plot and 5-year from CPRD), and the distribution of the underlying cause of death (ONS). The rate of post-diagnosis MLD-related treatments, including the proportion of patients who received haematopoietic stem cell transplant (HSCT) and the proportion of this subgroup with complications, equipment and co-morbidities, and pre-diagnosis co-morbidities and MLD-related symptoms will be reported (all CPRD and HES).

Health Outcomes to be Measured

Primary and secondary care resource use; co-morbidities; MLD-related symptoms treatments and equipment; survival; underlying cause of death; haematopoietic stem cell transplant (HSCT)-related complications.


- Chief Investigator -
Ellen Hubbuck - Corresponding Applicant - Pharmatelligence Limited t/a Human Data Sciences
David Heaton - Collaborator - Harvey Walsh Ltd
Matthew O'Connell - Collaborator - Harvey Walsh Ltd
Michael Wallington - Collaborator - OPEN VIE
Rhiannon Thomason - Collaborator - Harvey Walsh Ltd
Tracey Ellison - Collaborator - Harvey Walsh Ltd


HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data