GI tract and aging

Question 1

problems with oropharynx

Answer 1

teeth stained and worn
roots fragile and susceptible to fracture
periodontal disease is common. tooth loss.
edentulous - ill fitting dentures
15% problems with swallowing
Mastication - tongue muscles decreased
40% complain of dry mouth - decreased saliva production
impairment of laryngeal reflex - increased aspiration

Question 2

problems with esophagus

Answer 2

Significant impairment of motility reflects disease
Modest changes in motility
Decreased sphincter relaxation and pressures
Reduced peristaltic contractions
Delayed esophageal emptying
Esophageal dilation
Decreased neurons in myenteric plexus

Question 3

Changes with stomach

Answer 3

Gastric acid secretion is well preserved
1/3 have atrophic gadtritis/achlorhydria
NSAID gastropathy is more common
Gastric emptying is delayed with mixed or solid meals but not liquid meals

Question 4

Changes in liver

Answer 4

Decline in size secondary to reduced regeneration
Decreased blood flow to the liver
Reduced drug metabolism 
Albumin synthesis may decrease
Expression of inflammation related genes

Question 5

Changes to pancreas

Answer 5

weight of the pancreas declines
narrowing of ducts
exocrine function remain adequate
Decline in insulin secretion in rodents

Question 6

Small intestine

Answer 6

Structure and absorptive function appears well preserved
LActase activity is decreased but sucrase and maltase are unaffected
Normal mannitol absorption

Question 7

Canges in nutrient absorption

Answer 7

Decreased - vitamin b12
lactose
calcium
vitamin D
Iron 
Zinc 
Magnesium

Increased - vitamin A

Question 8

Colorectal Changes

Answer 8

Structural Changes - increased collagen, elastic, elaunin and oxytalan fibers and decreased neuronal density

Transit time - little evidence for major change

Fecal impaction
Constipation increased - prevalent among women
Pressure threshold that elicits sense of rectal filling increases

Question 9

Changes in microbiota

Answer 9

Relatively stable throughout adult life
changes in diet, gastrointestinal function and host immune system may impact flora
INcreased numbers of faculative anaerobes and decreased beneficial lactobacilli and bifidobacteria
Greater susceptibility to disease may result

Question 10

What are synbiotics?

Answer 10

combination of pre- and probiotics

Question 11

Changes in nutrient requirements

Answer 11

increased:
protein?
calcium
vitamin D
folate
vitamin b12

Decreased:
Energy
Vitamin A
Iron in post menopausal women