The Association Between Existing Health Conditions and Adverse Events From Botulinum Toxins: Findings From a UK Cross-sectional Survey in 2024.

[BACKGROUND] There is growing demand for Botulinum toxin (BoNT) injections in the UK. However, there is a scarcity of research in relation to associations between medical conditions and BoNT adverse events.

[OBJECTIVES] To investigate cross-sectional associations between existing medical conditions and the likelihood of adverse events in a large sample of UK BoNT users.

[METHODS] A cross-sectional observational survey on individuals' (≥18 years) experiences and adverse events with cosmetic BoNT injections. Data were collected on participants age, gender, existing health conditions, acute and long-term adverse events following BoNT treatment. To investigate the association between pre-existing physical conditions and the occurrence of post-BoNT adverse effects, multivariable logistic regression models were performed.

[RESULTS] Nine hundred and nineteen participants who received BoNT were included in the analysis. Multivariable logistic regression revealed that several pre-existing physical and psychiatric conditions were significantly associated with increased odds of specific post-BoNT adverse effects. Notably, individuals with skin disease (odds ratio [OR] 22.95, 95% confidence interval [CI] 2.64-132.03, P = .001), type 1 diabetes mellitus (OR 110.34, 95% CI 3.85-3381.06, P = .002), chronic migraine (OR 7.69, 95% CI 1.84-27.61, P = .003), and thyroid disorders (OR 6.18, 95% CI 1.27-23.44, P = .012) demonstrated significantly higher odds of developing nausea following BoNT administration. Multiple other significant associations were found between numerous existing health conditions and numerous adverse events.

[CONCLUSIONS] This study found that autoimmune, endocrine, neurological, and mental health comorbidities significantly increase the likelihood of adverse outcomes, ranging from bruising and ptosis to mood disturbance, neuromuscular weakness, and apparent treatment failure.