Prevalence of Pompe's Disease in Respiratory Clinics (PURF)

Prevalence of Pompe's Disease Amongst Patients With Unexplained Respiratory Muscle Weakness or Respiratory Failure

Pompe's disease is a very rare condition which causes weakness of the respiratory muscles and may therefore cause symptoms of breathlessness or even respiratory failure, requiring the use of a ventilator at night. Recently a treatment for this condition has become available as well as a simple diagnostic test. However, we believe it is possible that there are patients with this condition who are presently undiagnosed attending respiratory clinics.

We would like to complete an observational study of patients with respiratory muscle weakness of an unknown cause, who are attending respiratory clinics at two London centres, to determine whether patients attending these services have undiagnosed Pompe's disease.

Study Overview

• Status: Unknown
• Conditions: Pompe's Disease
• Intervention / Treatment: Other: Prospective observational study

Detailed Description

Participation in the study will involve taking measurements of respiratory muscle strength, lower limb strength and collecting blood samples to test for enzymes which relate to Pompe's disease. These measures will be completed during a routine clinic visit. Participation will also involve the study coordinator accessing medical notes to gain information about disease history.

The study aims to collect information about the number of patients attending respiratory clinics with undiagnosed Pompe's disease and the characteristics of these patients so that other specialist services could use these criteria to identify patients who may benefit from investigations and treatment. If any participants are diagnosed with Pompe's disease and could benefit from treatment medical staff would refer them for treatment at local UK centres.

• Study Type: Observational
• Enrollment (Anticipated): 400

Contacts and Locations

• Study Contact: Name: Michael Polkey; Phone Number: 8058 0207 352 8121

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Adults aged over 18 presenting to respiratory clinics with respiratory muscle weakness of an unknown cause.

Description

Inclusion Criteria:

Patients presenting to home mechanical ventilation or other respiratory clinics:

who are over 18 years old with unexplained respiratory muscle weakness with breathlessness and/or type II respiratory failure which may be treated by a ventilator which is: unexplained by a known pulmonary disease, radiological abnormality or distortion of body hiatus (e.g scoliosis or massive obesity defined as BMI > 50 kg/m2), associated with a restrictive ventilatory defect or associated with unexplained muscle weakness.

Exclusion Criteria:

respiratory muscle weakness confirmed to be due to another cause known to have Pompe's disease at time of referral

Study Plan

How is the study designed?

Design Details

• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The prevalence of undiagnosed adult onset Pompes disease. This will be assessed through dry blood spot testing measuring α-glucosidase (GAA) deficiency and the Activity Ratio +/Acarbose.	dry blood spot testing	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
CK levels	blood tests	12 months
Respiratory muscle strength	Using sniff nasal inspiratory pressure, spirometry in lying and sitting, maximal inspiratory and expiratory mouth pressure	12 months
Respiratory failure	Blood gases	12 months
Muscle weakness	performance on the short physical performance battery	12 months
Disease history	review of notes to establish duration of symptoms, time interval between presentation and referral to secondary care and any signs of respiratory failure or respiratory muscle weakness at presentation.	12 months

Collaborators and Investigators

• Sponsor: Royal Brompton & Harefield NHS Foundation Trust
• Collaborators: Genzyme, a Sanofi Company

Study record dates

Study Major Dates

• Study Start: September 1, 2015
• Primary Completion (Anticipated): September 1, 2016
• Study Completion (Anticipated): September 1, 2016

Study Registration Dates

• First Submitted: August 17, 2015
• First Submitted That Met QC Criteria: August 17, 2015
• First Posted (Estimate): August 18, 2015

Study Record Updates

• Last Update Posted (Estimate): August 18, 2015
• Last Update Submitted That Met QC Criteria: August 17, 2015
• Last Verified: August 1, 2015

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Genetic Diseases, Inborn; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Lysosomal Storage Diseases; Brain Diseases, Metabolic; Brain Diseases, Metabolic, Inborn; Lysosomal Storage Diseases, Nervous System; Glycogen Storage Disease; Glycogen Storage Disease Type II
• Other Study ID Numbers: 2015LF006B

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No