No Association of Complex Regional Pain Syndrome and Other Neurological Disorders with Human Papillomavirus Vaccination in a Large-Scale Real-World Database

Establishing evidence of vaccine safety is critical for optimizing vaccine coverage. This study aimed to assess the risk of developing neurological disorders following human papillomavirus (HPV) vaccination. This retrospective cohort study compared the risk of developing neurological disorders between HPV-vaccinated and unvaccinated cohorts using the TriNetX platform. Outcomes included complex regional pain syndrome (CRPS), postural orthostatic tachycardia syndrome (POTS), polyneuropathies, dysautonomia, Guillain-Barré syndrome (GBS), encephalitis, myelitis or optic neuritis, Bell's palsy, epilepsy, narcolepsy, and intracranial injury (negative control outcome). The hazard ratios (HRs) were estimated by propensity score matching. In the USA, following propensity score matching, 715,540 participants from each cohort were matched. The HRs were not increased following vaccination for any of the investigated outcomes, including CRPS, POTS, polyneuropathies, dysautonomia, GBS, encephalitis, myelitis or optic neuritis, Bell's palsy, epilepsy and narcolepsy. No increased risk of the selected neurological adverse events was observed in the vaccinated group. The data should be interpreted with caution given potential residual confounders and a possibility that high-risk population with neurological conditions were less likely to receive the vaccination. This study contributes to the establishment of evidence for the safety of HPV vaccines.