Introduction

The estimated global prevalence of biopsy-confirmed celiac disease (CeD) is 0.7% and sero-positive prevalence is 1.4%. Differences in definitions of CeD cases and at-risk populations, as well as underdiagnosis, may affect accurate estimation of the size of the diagnosed CeD population. In this study, we calculated the 10-year prevalence of diagnosed CeD in the USA using different CeD case definitions and at-risk populations.

Aims & Methods

A prevalence analysis of CeD cases was conducted using data collected from the Optum Clinformatics^® Data Mart, a US claims database. Prevalence calculations were based on two different definitions of CeD cases. Case definition 1 included any of the following: 1) International Classification of Diseases (ICD)-9/-10 diagnostic codes for CeD (≥ 1 inpatient or ≥ 2 outpatient codes), 2) tissue transglutaminase immunoglobulin A (tTG-IgA) positive serology or 3) biopsy-confirmed CeD (defined as esophagogastroduodenoscopy [EGD] followed by an ICD diagnostic code for CeD used as proxy). Case definition 2 was defined as the first ever positive tTG-IgA test followed by biopsy-confirmed CeD. The prevalence of diagnosed CeD was estimated for each study year from 2013 to 2022. Prevalence estimations were age- and sex-standardized using 2022 US Census data.

Results

The total population (denominator) comprised ~81 million individuals; of whom, 110,140 had ≥ 1 inpatient or ≥ 2 outpatient diagnostic codes for CeD, 41,184 had ≥ 1 positive tTG-IgA test and 44,641 had biopsy-confirmed CeD. Among all individuals that were tested for tTG2-IgA, 0.85% (95% confidence interval [CI]: 0.82, 0.89) were positive for CeD. The age- and sex-standardized prevalence of diagnosed CeD according to case definition 1 modestly increased from 0.27% (95% CI: 0.27, 0.27) in 2013 to 0.35% (0.34, 0.35) in 2022. Over the same time period, the age- and sex-standardized prevalence of diagnosed CeD according to case definition 2 increased from 0.01% (0.01, 0.01) to 0.03% (0.03, 0.03), respectively.

Conclusion

The overall prevalence of diagnosed CeD in the USA modestly increased from 2013 to 2022. During this same time period, the proportion of patients who underwent an EGD after a positive tTG-IgA test steadily rose. Validation of the CeD case definitions used in this study will be important to enable these results to be replicated or refuted. Furthermore, a standardized and validated CeD case definition will support comparisons between studies and inform better clinical care/disease management.

Disclosure

MA, SM, NC, KG and DAL are employees of Takeda Development Center Americas, Inc. and receive stock or stock options.

Introduction

Gastric cancer remains one of the leading causes of death internationally and a major health concern in the United States (US). To develop better prevention strategies, this study quantifies trends in gastric cancer related mortality, stratified by age, sex, region, urbanity, and race over two decades.

Aims & Methods

Our study used the CDC WONDER database to analyze death certificates from 1999 to 2022 across the U.S. ICD codes C16.0-C16.9 were used to identify the relevant cases. Demographic variables such as sex, race, age, urban-rural classification, and census regions were analyzed. Trends in AAMR were assessed using the Joint Point Regression Program to determine annual percentage changes (APC).

Results

Overall mortality related to malignant stomach neoplasms in the US declined significantly (Table 1) from 79.26 (1999) to 44.81 (2022), with notable periods of steep decrease between 1999–2006 (APC -3.51, 95% CI: -5.16 to -2.78) and 2006–2018 (APC -2.27, 95% CI: -3.55 to -1.83). Men consistently exhibited higher mortality rates than women (overall men: 81.14 vs women: 42.10). Men experienced an initial significant drop from 113.45 to 78.68 (1999–2009, APC -3.55), followed by a slower decrease till 2022 (APC -2.22). Women's mortality showed an initial sharp decline (1999–2008, APC -3.11), then a modest reduction from 2008–2018 (APC -1.96), plateauing thereafter.

Racially, Non-Hispanic (NH) Black individuals exhibited the highest mortality (109.37), followed by NH Asians/Pacific Islanders (102.47), Hispanic/Latino (91.93), NH American Indian/Alaskan Natives (78.21), and NH White (44.85). NH Blacks demonstrated a marked initial decrease (159.46 to 119.13 by 2017) then plateaued. NH Whites showed a continuous decline (1999–2018), slowing post-2018. Hispanics had two significant declining periods (1999–2011, APC -2.82; 2011–2022, APC -1.56), whereas NH Asians and NH American Indians steadily declined throughout.

Mortality by age was highest among older adults (202.46), followed by middle-aged (60.58) and young adults (40.55). Older adults had two notable decreasing phases (1999–2009, APC -3.56; 2009–2018, APC -2.89), with slower decline afterward. Middle-aged adults showed an initial steep decline (1999–2005, APC -3.65), followed by gradual reduction (2005–2022, APC -0.79). Young adults exhibited minimal, non-significant declines throughout.

Regionally, the Northeast showed highest mortality (64.78), followed by West, South, and Midwest. Both metropolitan and non-metropolitan areas saw significant mortality reductions, with non-metropolitan areas consistently having higher rates overall.

Table 1. Annual Percent Change (APC) in mortality rates by selected demographics, 1999–2022.
APC values are presented with 95% confidence intervals (CI). Asterisk (*) indicates statistically significant APC values (p < 0.05).

Conclusion

Gastric carcinoma has poor prognosis, and although the general trend is decreasing across all socio-demographic areas, further research is required for targeted interventions and health policies for populations at high risk of dying.

References

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Disclosure

No conflicts of interest to disclose.