Q&A: Lipid-lowering drugs linked to increased risk for severe insect sting anaphylaxis
Key takeaways:
- Patients on lipid-lowering medications were nearly twice as likely to experience a severe reaction.
- Considering the widespread use of these medications, these findings represent a significant risk.
BOSTON — Patients who were taking lipid-lowering medications experienced more severe anaphylaxis after insect stings, according to an abstract presented at the American College of Allergy, Asthma & Immunology Annual Scientific Meeting.
The retrospective chart review included 728 patients (413 female; median age, 42 years; age range, 2-90 years) who had anaphylaxis to insect stings in the United States and Canada between 2010 and 2023.
Among all patients, 200 (27%) had severe reactions and 528 (73%) had mild to moderate reactions. Among patients on lipid lowering medications (LLMs), 38 (44%) had severe reactions, while 48 (56%) had mild to moderate reactions.
Healio spoke with author Kaylee Sohng, a PGY3 internal medicine resident at the University of Toronto, to find out more.
Healio: What prompted this study?
Sohng: Previous research in both animal and human models has shown that high levels of platelet-activating factor (PAF) increase the severity of anaphylaxis. PAF is inactivated by PAF acetylhydrolase (PAF-AH), and lower levels of PAF-AH are associated with more severe anaphylactic reactions. Notably, PAF-AH circulates in the blood complexed to low-density lipoprotein (LDL). This led us to question whether LLMs, which reduce LDL levels, could also lower PAF-AH levels and increase PAF activity. Based on this mechanism, we hypothesized that patients taking LLMs are at a higher risk for severe anaphylaxis compared to those not on these medications.
Healio: What did your study find?
Sohng: Our study identified LLMs as a novel and significant risk factor for severe insect sting anaphylaxis. Patients taking LLMs were found to have nearly twice the odds (adjusted odds ratio = 1.9; P = 0.01) of experiencing severe anaphylaxis (Brown Severity Score III) compared with those not on LLMs. This association remained significant after adjusting for confounders including age, sex, comorbidities (mastocytosis, hereditary alpha tryptasemia, respiratory disorders), and concurrent use of other medications such as beta blockers and ACE inhibitors.
Healio: What makes these findings significant?
Sohng: Our findings are significant because they uncover a previously unrecognized risk factor for severe anaphylaxis. Given the widespread use of LLMs, this discovery carries important implications for clinical practice, particularly for individuals at heightened risk of severe allergic reactions.
Healio: How can doctors use these findings to improve the care they provide?
Sohng: Physicians can use these findings to identify patients on LLMs as a high-risk group for severe anaphylaxis and incorporate this information into clinical assessments. For these patients, we should prioritize consideration of venom immunotherapy, frequent follow-up care and allocation of additional time to counsel on the importance of carrying epinephrine auto-injectors and practicing behavioral strategies to avoid known triggers.
Healio: How can this research inform future public health policy/future research?
Sohng: Our hypothesis was driven by the pathway involving PAF, PAF-AH, and LDL We should also consider the off-target effect of LLMs as contributors to anaphylaxis severity. Prospective studies should be undertaken to examine this observed link between LLMs and anaphylaxis severity. If confirmed, these findings could change clinical recommendations for the duration of venom immunotherapy protocols and shape patient counseling strategies, particularly for those starting LLMs who have known severe allergies or are at high risk of anaphylaxis.
For more information:
Kaylee Sohng can be reached at kaylee.sohng@mail.utoronto.ca.