Risk of side-effects from long-term use of inhaled steroids in asthma

Study type
Protocol
Date of Approval
Study reference ID
21_001656
Lay Summary

Inhaled steroids are the main treatment for the lung condition asthma. Nearly all the good effects from inhaled steroids can be achieved from a low dose. Asthma guidelines recommend that the inhalers should be used at the lowest dose possible that would mean the patient has the lowest risk of symptoms. However, patients with milder asthma are often prescribed higher doses than they need. Oral steroids have been found to cause many health problems including eye problems, thinning of bones, fractures and diabetes. In other similar lung conditions to asthma, inhaled steroids have also been found to cause some side effects, such as thin bones. Although in asthma the dose of inhaled steroids is usually low, people use them for many years. The long-term use of inhaled steroids may cause some of the side-effects that are found with the much higher doses in oral steroids. This study will investigate how likely side-effects are from inhaled steroids in people with asthma.

Technical Summary

A cohort of asthma patients will be drawn from the Gold and Aurum databases. The cohort will be a new-user design for inhaled corticosteroids (ICS). The exposure will be incident ICS prescriptions. The outcomes with be new onset osteoporosis, fractures, diabetes, cataract, glaucoma and excessive bruising. These will be identified in their primary care records, CPRD, and secondary care, Hospital Episodes Statistics. Multivariable Cox proportional hazards regression and propensity methodology will be used to examine associations. To increase robustness of findings, a nested case-control will also be drawn, measuring the same association of ICS use and potential known corticosteroid side effects. Multivariable conditional logistic regression will be used to examine associations. Within the analyses for each outcome, we aim to measure the relative risk, absolute risk, dose-response, drug-specific effects and identify those most at risk.

Health Outcomes to be Measured

New onset osteoporosis, fragility fractures, diabetes, cataract, glaucoma and excessive bruising

Collaborators

Chloe Bloom - Chief Investigator - Imperial College London
Chloe Bloom - Corresponding Applicant - Imperial College London
Azeem Majeed - Collaborator - Imperial College London
Freda Yang - Collaborator - Imperial College London
Mark Cunningham - Collaborator - Imperial College London
Paul Cullinan - Collaborator - Imperial College London
Wisia Wedzicha - Collaborator - Imperial College London

Linkages

HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;CPRD Aurum Mother-Baby Link;CPRD Aurum Pregnancy Register