age-associated changes in the digestive system

Introduction

The digestive system undergoes change with aging.

Most GI signs & symptoms are due to pathology.

Medications can cause GI disorders in the elderly.

Physiology

• increased incidence of colonic diverticuli
• altered mastication & swallowing
  • diminished saliva production
• decreased splanchnic blood flow
• diminished upper & lower esophageal sphincter resting pressure
• diminished intra-abdominal lower esophageal sphincter length
• increased esophageal dysmotility, increasingly ineffective peristalsis
• decreased liver size, cell mass & blood flow
• impaired clearance of drugs that require extensive phase 1 metabolism
• decreased inducibility in mixed-function oxidase
• mild decrease in bilirubin
• hepatocytes accumulate lysosomes, residual bodies, lipofuscin
• loss of gastric parietal cells
  • decreased acid production
  • decreased vitamin B12 absorption
• impaired response to gastric mucosal injury
• impaired sense of gastroesophageal reflux
• diminished pancreatic mass & secretory reserves
  • increased lipofuscin & fat deposition in pancreas
• decrease in colonic peristalsis
  • increased incidence constipation
• altered intestinal absorption
  • diminished Ca+2 absorption
  • diminished iron absorption
• decrease in gut-associated lymphoid tissue (GALT)
  • movement of T-cells into & out of Peyer's patches may be compromised
• increase in mucosal cell atrophy
• enteric neurons may exhibit a senescent phenotype
• changes in intestinal flora with age correlate with diet & health status

More general terms

• age-related physiological changes

Additional terms

• digestive system
• digestive system disease