BackgroundHidradenitis suppurativa (HS) is a systemic inflammatory condition associated with obesity, metabolic syndrome, and environmental factors. Bariatric surgery (BS) is effective in reducing weight and resolving obesity-related medical problems. ObjectivesThe aim of this case-control study is to evaluate the effects of BS on the occurrence and recurrence of HS in individuals with obesity. SettingNationwide administrative data study using the French national discharge database. MethodsWe compared 297,776 individuals with obesity and without a history of HS who underwent BS (BS group) with 2,735,930 individuals with obesity who did not receive BS (control group) to assess the incidence of de novo HS. From the same database, we compared hospitalization rates for HS recurrence between 310 individuals with obesity and HS who had BS (HS_BS group) and 3875 individuals with obesity who did not have BS (HS_control group). Propensity score matching using the nearest-neighbor method was implemented to create comparable patient groups. ResultsIndividuals with obesity and without a history of HS who received BS exhibited a significantly reduced risk of developing de novo HS (RR = .736 [.639; .847]). Among patients with a history of HS, those who underwent BS had a nonsignificantly reduced risk of HS recurrence (RR = .676 [.369; 1.238]) compared with those who did not. ConclusionBS reduces the risk of developing de novo HS and seems to have a protective effect on its recurrence in individuals with obesity, although the latter effect was not statistically significant.