Can topical corticosteroids lead to T2D?

Takeaway

• High-potency topical corticosteroids (TCSs) may have diabetogenic effects.

Why this matters

• Topical corticosteroids used to treat chronic inflammatory and pruritic skin conditions can be absorbed and reach the systemic circulation.
• They were initially developed primarily for short-term use, but long-term dermatologic use is now common.

Study design

• 2 matched case-control studies of 115,218/group in Denmark and 54,944/group in UK, and 1 Danish cohort study (1,051,080 exposed; 1,638,393 unexposed).
• Funding:Lundbeck, Aage Bang, and A.P. Møller Foundations.

Key results

• In Danish case-control study, significant positive association seen between new-onset type 2 diabetes (T2D) and TCS in fully adjusted analysis (OR, 1.25; 95% CI, 1.23-1.28), with stronger association for increasing TCS potency (P_trend<.0001).
• Association also seen in UK case-control study after adjustment (1.23, 1.19-1.27), although no trend with TCS potency.  
• In Danish cohort study, T2D incidence was 5.73 vs 3.56/1000 person-years among TCS-exposed vs nonexposed, respectively, with absolute risk difference 2.17 (2.15-2.19)/1000 person-years and fully adjusted HR, 1.27 (1.26-1.29).
• Similar dose-response to the Danish case-control study.

Limitations

• Possible residual confounding, or reverse causality (i.e., people with T2D could use more TCSs for dry skin, etc.).
• Could not assess frequency, time, or amount of applied TCS/patient.
• Only adults studied.