Cohort profile: The Swedish Tattoo and Body Modifications Cohort (TABOO)

PURPOSE: The Swedish Tattoo and Body Modifications Cohort (TABOO) cohort was established to provide an infrastructure for epidemiological studies researching the role of tattoos and other body modifications as risk factors for adverse health outcomes. It is the first population-based cohort with detailed exposure assessment of decorative, cosmetic, and medical tattoos, piercing, scarification, henna tattoos, cosmetic laser treatments, hair dyeing, and sun habits. The level of detail in the exposure assessment of tattoos allows for investigation of crude dose–response relationships. PARTICIPANTS: The TABOO cohort includes 13 049 individuals that participated in a questionnaire survey conducted in 2021 (response rate 49%). Outcome data are retrieved from the National Patient Register, the National Prescribed Drug Register and the National Cause of Death Register. Participation in the registers is regulated by Swedish law, which eliminates the risk of loss to follow-up and associated selection bias. FINDINGS TO DATE: The tattoo prevalence in TABOO is 21%. The cohort is currently used to clarify the incidence of acute and long-lasting health complaints after tattooing based on self-reported data. Using register-based outcome data, we are investigating the role of tattoos as a risk factor for immune-mediated disease, including hypersensitisation, foreign body reactions and autoimmune conditions. FUTURE PLANS: The register linkage will be renewed every third year to update the outcome data, and we have ethical approval to reapproach the responders with additional questionnaires.