Age-Related Decline in Intestinal Villus Length: A Cross-Sectional Study on the Human Gut

Area of Science:

• Gastroenterology
• Gerontology
• Nutritional Science

Background:

• Age is a known predictor of poor response to nutritional support, often attributed to anabolic resistance.
• Impaired nutrient absorption due to aging was previously considered insignificant.
• Animal studies suggest age-related intestinal mucosal changes may affect absorption capacity.

Purpose of the Study:

• To investigate histological and histomorphometric changes in the duodenal mucosa associated with aging.
• To compare villus length and other histological features between younger and older adults.

Main Methods:

• A single-center observational cross-sectional study involving duodenal biopsies from younger (18-45 years) and older (≥70 years) adults undergoing upper endoscopy.
• Histological and histomorphometric analysis of biopsies, focusing on villus length.
• Collection of clinical and laboratory data, including nutrient levels.

Main Results:

• Older adults (≥70 years) exhibited significantly shorter duodenal villi (0.35 mm) compared to younger adults (0.57 mm) (p < 0.001).
• Age was inversely associated with villus length in multivariable regression analysis (p < 0.001).
• Older participants had lower levels of hemoglobin, iron, folate, vitamin B12, albumin, and vitamin D, despite normal inflammatory markers.

Conclusions:

• Aging is associated with intestinal mucosal changes, specifically villus shortening, supporting the concept of 'mucosal aging'.
• Villus shortening may indicate a reduced absorptive surface area in older adults.
• These findings suggest a potential contribution of mucosal aging to age-related nutritional vulnerability, though functional implications require further study.