Related Experiment Video
Updated: Sep 20, 2026

Frailty Assessment in an Aging Mouse Model
Published on: September 23, 2025
Association between biological aging and fecal incontinence, chronic diarrhea in U.S. adults: A retrospective
Siyuan Sun1,2,3, Chunyao Li1,2,3, Wenqian Yu4
1Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China.
Abstract:
ObjectiveTo investigate the associations of accelerated biological aging and its component biomarkers with chronic diarrhea (CD) and fecal incontinence (FI).MethodsThis cross-sectional study analyzed data from 5,443 participants in the 2005-2010 National Health and Nutrition Examination Survey (NHANES). PhenoAge was calculated using nine clinical biomarkers, and phenotypic age acceleration (PhenoAgeAccel) was derived from residuals obtained by regressing PhenoAge on chronological age (CA). Weighted t-tests and chi-square tests were used to compare baseline characteristics, and weighted logistic regression and restricted cubic splines (RCS) were used to analyze the associations. Subgroup analyses were performed to evaluate potential effect modification, and sensitivity analyses were conducted to assess the consistency of the main findings.ResultsPhenoAgeAccel was positively associated with FI, whereas no significant association was detected between PhenoAgeAccel and CD. Participants with FI had higher CA, PhenoAge and PhenoAgeAccel (P<0.05). FI prevalence increased across higher quartiles of PhenoAge and PhenoAgeAccel (P for trend<0.05). Fully adjusted models showed that Q4 of PhenoAge was associated with higher odds of FI than Q1 (OR = 2.559, 95% CI 1.012-6.468, P = 0.037). Similarly, Q4 of PhenoAgeAccel was associated with higher odds of FI than Q1 (OR = 1.571, 95% CI 1.097-2.250, P = 0.014). Participants with accelerated PhenoAge also had higher odds of FI than those with decelerated PhenoAge (OR = 1.417, 95% CI 1.084-1.851, P = 0.011). RCS analyses supported a significant positive linear association between PhenoAgeAccel and FI. Nine clinical biomarkers were evaluated for associations with FI. ALB (albumin), CRP (C-reactive protein), and RDW (red cell distribution width) showed significant linear associations with FI (all P for nonlinearity > 0.05), whereas LYM% (lymphocyte percentage) and MCV (mean corpuscular volume) showed significant nonlinear associations (all P for nonlinearity < 0.05). Creatinine (Cr), glucose (Glu), alkaline phosphatase (ALP), and white blood cell count (WBC) exhibited no significant associations with FI (all P for overall association > 0.05). Significant interactions were observed for age (P for interaction < 0.001) and diabetes status (P for interaction = 0.034), indicating that the PhenoAgeAccel-FI association varied according to these factors. Sensitivity analyses supported the robustness of the continuous PhenoAgeAccel-FI association, although statistical evidence weakened for quartile-based analyses.ConclusionsPhenoAgeAccel was significantly and linearly associated with FI in a nationally representative sample of U.S. adults, whereas no significant association was observed between PhenoAgeAccel and CD. Prospective studies are needed to confirm this association and clarify its temporal relationship.
Related Concept Videos
Development of Human Microbiota
Chronic Bowel Disorders: Introduction
Irritable Bowel Syndrome (IBS) is a common disorder affecting the gastrointestinal tract. The distinctive feature is recurrent abdominal pain associated with altered bowel movements, manifesting as constipation, diarrhea, or fluctuating between both. The...
Dysbiosis of the Gut Microbiota
Alzheimer Disease l: Introduction
Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
Anatomy of the Intestines