Topical corticosteroids and risk of type 2 diabetes: a nested case-control study

Study type
Protocol
Date of Approval
Study reference ID
17_016
Lay Summary

Elevated blood glucose levels and type 2 diabetes are well known side effects of corticosteroids when administered as tablets or injections. It is not yet known whether corticosteroids applied on the skin as creams or ointments undergo sufficient skin absorption to cause the same side effects. The few previous studies investigating this association have been conflicting. The aim of the current study is to assess whether topical corticosteroid use increases the risk of developing new onset type 2 diabetes using data from the Clinical Practice Research Datalink. Exposure to topical corticosteroids will be identified in patients with type 2 diabetes as well as individuals without type 2 diabetes, but with similar gender and age distribution. The data will be analysed using statistical models, and carefully interpreted. Knowledge of possible adverse effects is important for patient care and may help healthcare providers in assessing risks and benefits of specific treatments, as well as initiate relevant screening in high-risk patients.

Technical Summary

Hyperglycaemia and type 2 diabetes (T2D) are established adverse effects of systemic corticosteroids, however it is not yet known whether topically applied corticosteroids increase the risk of T2D. Few studies have investigated this association and have found conflicting results. The aim of this study is to assess the association between the use of topical corticosteroids and T2D in the UK. We will use CPRD records to establish a cohort of adults aged 18 years or older who have a first diagnostic code for T2D between January 1st 2007 and December 31st 2015. The study cases will be matched with a randomly selected control population without T2D, based on sex, age at diagnosis and GP practice. We will identify all prescriptions of topical corticosteroid agents given before the diagnosis or pseudodiagnosis, and based on a case-control design we will calculate crude and adjusted odds ratios using conditional logistic regression models. Relevant covariates are socioeconomic status, body mass index, smoking, psoriasis, atopic dermatitis and other administrations of corticosteroids, as these factors may be associated with the exposure, and may be an independent risk factor for the outcome. Age and gender are also potential confounders, however these will be controlled for by the matching process.

Health Outcomes to be Measured

Type 2 diabetes

Collaborators

Sonia Gran - Chief Investigator - University of Nottingham
Yuki Andersen - Corresponding Applicant - Copenhagen University Hospital Herlev and Gentofte
Alexander Egeberg - Collaborator - Copenhagen University Hospital Herlev and Gentofte
Filip Knop - Collaborator - Copenhagen University Hospital Herlev and Gentofte
Gunnar Gislason - Collaborator - Copenhagen University Hospital Herlev and Gentofte
Hywel Williams - Collaborator - University of Nottingham
Jacob Thyssen - Collaborator - Copenhagen University Hospital Herlev and Gentofte
Lone Skov - Collaborator - University of Copenhagen
Lu Ban - Collaborator - University of Nottingham
Nicholas Francis - Collaborator - Cardiff University

Linkages

Patient Level Index of Multiple Deprivation