Risk of self-harm and the use of leukotriene receptor antagonists and inhaled corticosteroids:a population-based study

Abstract

Background Whether leukotriene receptor antagonists (LTRAs) or inhaled corticosteroids (ICS) use can increase the risk of self-harm remains unclear. Objective To evaluate the association between self-harm and use of LTRA and ICS among patients with asthma. Methods This self-controlled case series (SCCS) study used data from the UK Clinical Practice Research Datalink linked to hospital and mortality records. We included patients with asthma aged ≥10 years who had at least one prescription of LTRA, one prescription of ICS, and an incident self-harm during 2005-2020. Incidence rate ratios (IRRs) of self-harm during periods of (presented in order of precedence if they overlapped): pre-LTRA, pre-ICS, LTRA-alone, ICS-alone, and combination use of LTRA and ICS, versus non-use, were calculated using conditional Poisson regression model. Additional analyses using SCCS extension, case-case-time-control, and cohort study designs were used to examine robustness of results. Results Among 313,943 individuals prescribed LTRA and ICS, 2,900 had incident self-harm. IRRs were 0.77 (95%CI=0.58-1.01) during pre-LTRA, 0.68 (95%CI=0.57-0.82) during LTRA-alone, and 0.70 (95%CI=0.56-0.86) during combination use. Further analysis suggested the self-harm incidence was lower during the first 90 days of LTRA use (IRR=0.74; 95%CI=0.58-0.95), before returning to non-use level (IRR=0.93; 95%CI=0.74-1.17). Comparable incidence to non-use was observed during pre-ICS (IRR=0.99; 95%CI=0.71-1.39) and ICS-alone (IRR=0.88; 95%CI=0.75-1.04). The results were robust across sensitivity analyses and study designs, which did not suggest increased risk of self-harm with LTRA/ICS use. Conclusion Using the SCCS design, which was based on comparisons within a population with both the outcome and exposure of interest, our study does not support an association between self-harm and LTRA or ICS in patients with asthma.