Review for 10.1186/s12876-025-04042-3 (2025)

Title: Global, Regional, and National Burden of Inflammatory Bowel Disease in persons Aged
60-89 years from 1992 to 2021
Version: 1 Date: 16 Mar 2025
Reviewer:  Anwar Ashraf Abouelnasr
Reviewer's report:
Dear Authors, please address the following points below
-While the study design and methodology are robust, the manuscript does not address potential
limitations, particularly those related to the GBD data. For example, the reliance on model-based
estimates and the potential inaccuracies in reporting and diagnosis of IBD in older populations
could affect the results.
-The paper could mention the limitations of the statistical models used (e.g., the assumptions
behind Joinpoint regression and Nordpred model), and how these might influence the
projections.
-Although the study provides detailed epidemiological trends, there is a lack of discussion on
how these findings translate into clinical practice or public health interventions.
The paper could expand on the implications of these trends for healthcare providers, such as
specific challenges in treating IBD in older adults (e.g., polypharmacy, comorbidities, and the
need for individualized treatment approaches).
-The study mentions the use of the Sociodemographic Index (SDI) and WHO regions for
classification but does not explore how specific sociodemographic factors (e.g., socioeconomic
status, urban vs rural settings, or healthcare access) might influence IBD burden across regions.
-Further analysis of how these factors contribute to regional and national variations in IBD
burden could provide deeper insights.
-While the study provides global and regional trends, the manuscript could provide more detailed
insights into specific countries or regions that show unusual trends or burdens. This would make
the study more relatable to specific policymakers or healthcare planners.
A brief comparison between regions with different healthcare infrastructures (e.g., developed vs
developing countries) might provide a more nuanced understanding of how healthcare systems
impact IBD outcomes.
-The introduction could expand on emerging risk factors for IBD, especially as they relate to
aging populations. Factors like diet, environmental exposures, and changes in gut microbiota in
older individuals could be important to mention as they influence the incidence and progression
of IBD.
-The Nordpred prediction model is used to forecast future trends, but there is no mention of
model validation or how well the model has been tested for IBD. A discussion on the accuracy
and potential variability of the predictions would strengthen the forecast's credibility.
-While the discussion provides a broad overview of the findings, there could be more clarity on
specific trends and what factors specifically influenced the changes observed. For example, it
mentions improvements in treatment and healthcare but doesn't specify the relative contributions
of factors like biologics, improved diagnostic capabilities, or other healthcare interventions.
-More details on the precise factors influencing gender differences in disease burden (such as
hormone-related factors or access to healthcare) would strengthen the analysis of gender trends.
-The study touches on the influence of urbanization and dietary habits but could provide more
specific examples or data on how these factors have contributed to the increased incidence in
middle SDI regions.
-The role of socioeconomic factors such as income disparities, education, or employment
status in influencing the burden of IBD in older populations could be further explored. For
instance, do higher-income populations have better access to healthcare, leading to better disease
management?
-The explanation of the four stages of IBD epidemiology (emergence, accelerating incidence,
compounded prevalence, and prevalence equilibrium) could benefit from more region-specific
examples. For instance, which countries or regions are currently in which stage, and how do
their healthcare systems differ?
-The discussion could expand on the challenges specific to low-middle and low-SDI regions,
such as limited healthcare access, underreporting, and diagnostic challenges.