Objectives-Clinical response is typically observed in most adults with celiac disease (CD) after treatment with a gluten-free diet (GFD). The rate of mucosal recovery is less certain. The aims of this study were 1) to estimate the rate of mucosal recovery after GFD in a cohort of adults with CD, and 2) to assess the clinical implications of persistent mucosal damage after GFD.Methods-The study group included adults with biopsy-proven CD evaluated at the Mayo Clinic who had duodenal biopsies at diagnosis and at least one follow-up intestinal biopsy to assess mucosal recovery after starting a GFD. The primary outcomes of interest were mucosal recovery and all-cause mortality.Results-Of 381 adults with biopsy-proven CD, 241 (73% females) had both a diagnostic and follow-up biopsy available for re-review. Among these 241, the Kaplan-Meier rate of confirmed mucosal recovery at 2 years following diagnosis was 34% (95% CI: 27%-40%), and at 5 years was 66% (95% CI: 58%-74%). Most patients (82%) had some clinical response to GFD, but it was not a reliable marker of mucosal recovery (p=0.7). Serological response was associated with confirmed mucosal recovery (p=0.01). Poor compliance to GFD (p<.01), severe CD defined by diarrhea and weight loss (p<.001), and total villous atrophy at diagnosis (p<.001) were strongly associated with persistent mucosal damage. There was a trend toward an association between achievement of mucosal recovery and a reduced rate of all-cause mortality (HR = 0.13, 95% CI: 0.02-1.06, p = .06), adjusted for gender and age.Conclusions-Mucosal recovery was absent in a substantial portion of adults with CD after treatment with a GFD. There was a borderline significant association between confirmed mucosal recovery (vs. persistent damage) and reduced mortality independent of age and gender. Systematic follow-up with intestinal biopsies may be advisable in patients diagnosed with CD as adults.