Background & Aims-The historical prevalence and long-term outcome of undiagnosed celiac disease (CD) are unknown. We investigated the long-term outcome of undiagnosed CD and whether the prevalence of undiagnosed CD has changed during the past 50 years.

The prevalence of CD in the United States was 0.71% (1 in 141), similar to that found in several European countries. However, most cases were undiagnosed. CD was rare among minority groups but affected 1% of non-Hispanic whites. Most persons who were following a GFD did not have a diagnosis of CD.

Background & Aims Outcomes of undiagnosed celiac disease (CD) are unclear. We evaluated morbidity and mortality of undiagnosed CD in a population-based sample of individuals ≥50 years of age. Methods Stored sera from a population-based sample of 16,886 Olmsted County, Minnesota residents ≥50 years of age were tested for CD based on analysis of tissue transglutaminase (tTGA) and endomysial antibodies (EMA). A nested case-control study compared serologically defined subjects with CD to age- and sex-matched, sero-negative controls. Medical records were reviewed for comorbid conditions. Results We identified 129 (0.8%) subjects with undiagnosed CD in a cohort of 16,847 older adults. A total of 127 undiagnosed cases (49% male, median age 63.0 years) and 254 matched controls were included in a systematic evaluation for more than 100 potentially coexisting conditions. Subjects with undiagnosed CD had increased rates of osteoporosis and hypothyroidism, as well as lower body mass index and levels of cholesterol and ferritin. Overall survival was not associated with CD status. During a median follow-up period of 10.3 years after serum samples were collected, 20 cases but no controls were diagnosed with CD (15.2% Kaplan-Meier estimate at 10 years). Conclusions With the exception of reduced bone health, older adults with undiagnosed CD had limited comorbidity and no increase in mortality compared to controls. Some subjects were diagnosed with CD within a decade of serum collection, indicating that although most cases of undiagnosed CD are clinically silent, some result in symptoms. Undiagnosed CD can confer benefits and liabilities to older individuals.