Background: The factors that determine whether an area of the body will be affected by hidradenitis suppurativa (HS) are unknown. Methods: To address these factors, we performed multivariate regression analyses in a cohort of 1,138 patients. Results: We found that the body sites affected occurred in specific combinations that were influenced by sex and body mass index. We also revealed unexpected correlations between some sites and other comorbidities such as inflammatory diseases, acne conglobata, or dissecting folliculitis of the scalp. Conclusion: Such correlations are crucial to unravel a disease as variable as HS and identify pathophysiological mechanisms to enable the provision of personalized management.