12) Adulthood and the Elderly (Part II) Flashcards
1
Q
When does the number of functional taste buds decrease?
A
60 years of age
2
Q
What are the consequences of a decrease in the number of functional taste buds?
A
- Decreases the capacity to taste and smell
- Reduces appetite
- Decreases palatability
- Decreases food intake
- Prescribed diets are low in taste
3
Q
What are the components of saliva?
A
- Water
- Electrolytes
- Mucus
- Glycoprotein enzymes
- Anti-bacterial compounds (IgA, lysozyme)
4
Q
What are the three primary functions of saliva?
A
1) Initiates the process of digestion of dietary starches and fats
2) Play a role in protection against dental caries
3) Lubricates food, allowing for the initiation of swallowing
5
Q
What is xerostomia?
A
Dry-mouth
6
Q
Xerostomia is present in 20% of the elderly. What are possible causes? (2)
A
- Drug intake (anti-hypertensives, anti-depressants, bronchodilators)
- Disease (e.g. autoimmune disease)
7
Q
What are the effects of a decrease in salivary secretion?
A
Increases the risk of infections and ulcers
8
Q
What is the effect of a decreased ability to swallow (dysphagia) due to a decreased salivary secretion?
A
May result in a decreased food intake
9
Q
What is a likely consequence of a decrease in esophageal function?
A
Dysphagia
10
Q
What are causes of dysphagia? (3)
A
- CNS changes
- Diabetic neuropathy
- Parkinson’s disease
11
Q
An individual is prone to dysphagia if there is impaired __________ function.
A
esophageal
12
Q
Choking increases the risk of which disease? Why?
A
- Pneumonia
- Food may be aspirated into the lungs
- Choking is one of the leading causes of death among the elderly population
13
Q
What are the primary functions of gastric acid?
A
- Acts as a chemical barrier against pathogenic colonization
- Facilitates food digestion
14
Q
What does the stomach lining contain to protect from gastric acid? What occurs if these mechanisms fail?
A
- A layer of thick mucus containing sodium bicarbonate
- Heartburn or peptic ulcers may develop
15
Q
Which gastric functions are impaired due to aging?
A
- Decrease in gastric acid production
- Decrease in parietal cell mass
- Decrease in the maintenance of commensal flora bacteria
16
Q
What are the effects of a decrease in pepsin due to aging?
A
- Decreases proteolysis
- Results in a decreased vitamin B12 exposure to intrinsic factor
- Decreased absorption of vitamin B12
17
Q
What are the effects of hypochlorhydria due to aging?
A
- Increase in pH in the proximal small intestine
- Causes bacterial overgrowth of the small GI (streptococci, lactobacilli)
18
Q
What is the effect of bacterial overgrowth of the small GI?
A
These bacteria compete for B-vitamins, which decreases optimal nutrient availability
19
Q
Dyspepsia increases the risk of ______.
A
ulcers
20
Q
What are the functions of the liver?
A
- Glycogen storage
- Decomposition of RBCs
- Plasma protein synthesis
- Hormone production
- Detoxification
21
Q
Why is the elderly highly susceptible to drug-related toxicity?
A
The liver no longer has the capacity to metabolize compounds properly due to a reduced production of drug-metabolizing enzymes
22
Q
What are the effects of a decrease in bile production with age?
A
- Increases food intolerance (fatty foods)
- Increases GI distress, causing gas, nausea, vomiting and diarrhea
23
Q
What are the effects of a decrease in the functioning sections of the pancreas with age?
A
A decrease in digestive enzyme production and nutrient absorption in the small intestine may occur with age, particularly if there is an underlying chronic disease
24
Q
What are causes of an increased risk of constipation in the elderly?
A
- Low-fiber intake due to food intolerance
- Difficulty consuming fibrous foods
25
What are the effects of diverticulosis?
- Discomfort
- Diarrhea
- Constipation
- May lead to diverticulosis (bleeding and bowel obstruction)
26
Which nutrient deficiencies are related to lactose intolerance?
- Vitamin A
- Vitamin D
- Vitamin B2
- Protein
27
What are functions of the kidney?
- Regulation of electrolytes
- Maintaining acid/base balance
- Regulating blood pressure
28
The renal mass decreases by 30% by __ years of age.
90
29
What are the effects of a decrease in renal mass?
1) Decreases renal function
| 2) Decreases the capacity to excrete waste products from diets with a high intake of protein or electrolytes
30
What are the effects of glomerulonephritis?
Difficulties in the excretion of drugs and vitamins when taken in excess
31
Which nutrient deficiencies are related to a decrease in renal function? Why?
- Vitamin D because the kidneys are responsible for its bioactivation
- Water, glucose and amino acids, which are excreted instead of absorbed
32
How does the decline in renal function affect thirst mechanisms?
Increases the risk of dehydration, which is further exacerbated by the heavy use of diuretics and laxatives
33
What is the effect of the decrease in function of the liver AND kidney?
- Accumulation of drug metabolites
| - May trigger a type III hypersensitivity response
34
What occurs during a type III hypersensitivity response?
- IgG and complement components attempt to bind to metabolites, forming immune complexes, which become subject of complement deposition, opsonization and phagocytosis
- Glomerulonephritis may occur as a response
35
About __% of individuals that are greater than 75 years of age meet the criteria for chronic kidney disease.
50
36
What are the five ways anti-vitamin drugs may block the actions of vitamins? (5)
1) Inhibiting their absorption
2) Binding to them (making them unavailable)
3) Enhancing their catabolism
4) Enhancing their excretion
5) Causing an inhibition of their activation in the body to an active form
37
What is polypharmacy a strong predictor for?
Malnutrition
38
Why is polypharmacy a strong predictor for malnutrition in the elderly?
- With increasing age, the body's ability to metabolize drugs decreases
- The elderly is normally prescribed multiple medications
39
What are the four mechanisms by which drugs undergo movement in the body?
- Absorption
- Distribution
- Metabolism
- Excretion
40
What are possible effects of low serum albumin concentration on drugs?
May increase the availability of drugs and potentiate their effects
41
Where does drug metabolism normally occur? What is it facilitated by? What normally occurs?
- Liver
- Cytochrome P-450
- Conversion of fat-soluble compounds to water-soluble compounds
42
What are the effects of grapefruit on drug metabolism? What is the mechanism by which this occurs?
- Inhibit intestinal metabolism (by inhibiting cytochrome P-450) of numerous drugs
- Enhances their effects and risks of toxicity
43
Why have hospitals and healthcare centers removed grapefruit from their menu?
- Grapefruit enhances the risk of toxicity of certain drugs
| - The effects may persist for 72 hours
44
What are the effects of monoamine oxidase inhibitors on nutrient metabolism?
- Prevent the breakdown of pressor agents in food (substances that increase BP)
- May cause a hypertensive crisis
45
What are the effects of vitamin K on Warfarin?
Vitamin K allows for the production of more clotting factors, making Warfarin less effective
46
What are the effects of Methotrexate and pyrimethamine on nutrient metabolism?
Folic acid antagonists
47
How may folic acid deficiency be prevented in individuals consuming folic acid antagonists?
- Consumption of greater folic acid
| - Consumption of folinic acid (reduced form of folic acid), which does not require conversion to the active form
48
What drug may increase the risk of GI bleeding if ingested with alcohol?
NSAIDs
49
Define a drug-nutrient interaction.
The result of action between a drug and a nutrient that would not happen with the nutrient or the drug alone
50
Define a food-drug interaction.
Broad term that includes drug-nutrient interactions and the effect of a medication on
nutritional status
51
How do cholesterol-lowering drugs affect nutrient metabolism?
- Act as bile acid sequestrants, preventing reabsorption of bile salts
- Decreases fat-soluble vitamin absorption
52
How do antibiotics affect nutrient metabolism?
- Damage to the GI tract
- Destroying intestinal mucosa, villi and microvilli, as well as brush-border enzymes
- Reduces nutrient absorption
53
How do anti-inflammatory drugs affect nutrient metabolism? (3)
1) Inhibit lactase
2) Directly damage the gut
3) Decrease fat and micronutrient absorption
54
How do laxatives affect nutrient metabolism? What do they contain?
May contain emollients, which dissolve fats and fat-soluble vitamins, which are subsequently excreted in feces
55
Which nutrients do laxatives influence? Why?
- Fats and fat-soluble vitamins (contain emollients)
| - Calcium and potassium (decreased transit time)
56
A high-fiber diet may decrease the absorption of which medication?
Tricyclic anti-depressants
57
Which medications alter the ability to absorb minerals, particularly iron and calcium?
- Chemotherapeutic agents
- NSAIDs
- Antibiotics
58
How do anti-ulcer drugs affect nutrient metabolism?
- Decreases HCl production
| - Decreases intrinsic factor secretion, and binding/absorption of vitamin B12
59
How do anti-ulcer drugs affect the pH of the GI tract?
Increase in pH
60
What are the effects of an increase in pH on nutrient metabolism? Which nutrients are affected?
Impairs the absorption of calcium, iron, zinc, folic acid and B-carotene
61
Which nutrients do Ciproflaxacin and tetracycline complex with?
- Calcium
- Iron
- Magnesium
- Zinc
62
What is the mechanism of action of loop diuretics?
Inhibit the sodium-potassium co-transporter in the thick ascending loop of Henle
63
Which nutrient do loop diuretics affect?
Increase the renal excretion of thiamine
64
Which nutrients do thiazide diuretics affect?
- Increase the excretion of potassium and magnesium
| - Reduce the excretion of calcium
65
What is a possible effect of a high dosage of a thiazide diuretic?
Hypercalcemia
66
Which nutrients do potassium-sparing diuretics affect?
Increase the excretion of sodium, chloride and calcium
67
Which nutrient does aspirin affect? How?
- Increases folate excretion
| - By binding to folate-binding sites on albumin
68
Which drugs are more potent if there are low albumin levels? (3)
- Aspirin
- Phenytoin
- Warfarin
69
What are the effects of a greater proportion of adipose tissue on drug metabolism?
Causes fat-soluble drugs to accumulate, which increases the risk of toxicity
70
Which nutrients do corticosteroids affect?
- Decrease sodium and water excretion
| - Increase potassium and calcium excretion
71
Which supplements are recommended in an individual utilizing corticosteroids?
- Potassium
- Calcium
- Vitamin D
72
What is particular about Alendronate, an anti-osteoporosis drug?
Must be ingested while sitting upright for 30 minutes to avoid esophagitis
73
What is acute diarrhea?
An episode lasting less than 2 weeks
74
What is chronic diarrhea?
Diarrhea lasting from 3 to 6 weeks
75
What may be due to the increase in likelihood of developing diarrhea with age?
Changes in immune and non-immune defenses associated with age
76
What is the most common cause of diarrhea in the elderly? What is it related to?
- Drug therapy
| - Dose-related
77
What is the most common iatrogenic cause of diarrhea in the elderly? What are the characteristics?
- Antibiotics
| - Often mild and self-limiting
78
How do antibiotics cause diarrhea?
- Results in a temporary alteration of the colonic bacteria and may damage the small intestinal mucosa
- Decreases colonic fermentation of carbohydrates, which act as osmotic agents
79
What are examples of osmotic agents that may cause diarrhea?
- Anti-ulcer medication (Cimetidine)
- Laxatives
- Antacids
80
How do antineoplastic drugs cause diarrhea?
Damaging immature epithelial cells, compromising their absorptive funciton
81
What are contributing factors to drug therapy-related diarrhea? (4)
- Polypharmacy
- Self-medication
- Non-compliance
- Inappropriate drug prescribing
82
Define bone remodeling.
The replacement of old bone with newly synthesized bone tissue
83
What is the primary function of osteoblasts?
Synthesize the bone matrix
84
What are the primary functions of osteoclasts?
- Dissolve bone minerals with acids
| - Digest the bone matrix with the recruitment of phagocytes to remove the protein
85
Define osteoporosis.
- Reduced bone of normal composition
| - Bone density is 2.5 SD below the level of healthy young individuals
86
What postpones osteoporosis?
A high peak bone mass early in life
87
How does bone formation compare to resorption before peak bone mass is reached?
Bone formation continues at a pace that is faster than resorption
88
What is the yearly resorbed bone loss that occurs from age 30 to menopause?
1.2% per year
89
What is the yearly resorbed bone loss that occurs for 6 to 8 years during menopause?
3 to 5% per year
90
What is the main determinant of peak bone mass?
Calcium intake
91
When does the maximal rate of accretion of bone mass occur?
During the pubertal growth spurt
92
When do men and women experience the same rapid bone loss?
- In their 50s, men do not experience rapid bone loss
| - By 65 or 70, men and women experience the same bone loss
93
What are the three factors that place men at a decreased risk for developing osteoporosis? (3)
1) Their larger skeleton
2) Bone loss starting later and slower in men
3) The lack of rapid hormonal changes in men
94
Which hormones, affected by aging, increase the risks of developing osteoporosis?
- Decrease in GH
- Decrease in hepatic IGF-1
- Decrease in sex hormones
95
How may anorexia predispose an individual to osteoporosis?
- Decrease in estrogen due to low-body weight
- Calcium deficiency
- Malnutrition
96
How do glucocorticoids predispose an individual to osteoporosis?
- Suppress bone formation
- Impair osteoblastogenesis
- Inhibit the synthesis of IGF-1
97
Which cells are associated with type I osteoporosis? How do they vary?
Increase in osteoclast activity
98
What is post-menopausal osteoporosis?
Type I osteoporosis
99
What is senile osteoporosis?
Type II osteoporosis
100
Which type of bone is lost in type I osteoporosis?
Trabecular bone
101
What are the two mechanisms by which estrogen prevent osteoporosis?
1) Stimulates apoptosis of osteoclast precursor cells
| 2) Suppress the production of bone-resorbing cytokines
102
What is the age of onset of type I osteoporosis?
50 to 70 years of age
103
The ratio of which hormones is associated with a greater risk of developing type I osteoporosis?
- Menopause causes a lower estrogen to PTH ratio
| - PTH mobilizes calcium from bone, increasing bone resorption
104
Which type of bone is lost in type II osteoporosis?
Cortical bone loss
105
What is the age of onset of type II osteoporosis?
- 40 years of age
| - Occurs slowly and steadily
106
Which cells are associated with type II osteoporosis? How do they vary?
Underactivity of osteoblast
107
If the cause of type II osteoporosis is age-related, what is it called?
Senile osteoporosis
108
If the cause of type II osteoporosis is unknown, what is it called?
Idiopathic osteoporosis
109
What is the predominant feature of age-related bone loss?
The accumulation of bone marrow fat at the expense of osteoblastogenesis
110
How do adipocytes affect osteoblasts?
Adipocytes inhibit osteoblast activity
111
Which hormone plays a greater role in age-related bone loss in men: estrogen or testosterone?
Estrogen
112
______ and ______ deficiencies contribute to secondary hyperparathyroidism.
Calcium
| vitamin D
113
How does hyperparathyroidism affect osteoclastic activity?
Increases osteoclastic activity and cortical bone loss
114
The screening for what should occur during the peri-menopausal period?
Osteopenia
115
Define osteopenia.
Bone mineral density above one SD and below 2.5 SD of the young adult mean
116
Which nutrient may aid in the control of bone mineral loss during post-menopause?
Calcium
117
What are causes of estrogen deficiency?
- Decrease in ovarian function
- Anorexia nervosa
- Removal of ovaries
118
Which treatments for osteoporosis have fallen out of recommendation in recent years? Why?
- Hormone replacement therapy (HRT) and selective estrogen receptor modulators (SERMs)
- Increased risk of breast cancer and CVD
119
What is the first line of treatment for osteoporosis?
Bisphosphonates
120
What are the mechanisms of action of bisphosphonates? (3)
1) Osteoclast apoptosis
2) Osteoblast differentiation
3) Inhibition of bone marrow adipogenesis
121
Why are the elderly and women with osteoporosis thought to absorb calcium less efficiently?
Due to a deficiency in the active form of vitamin D
122
Which derivative of vitamin D has demonstrated beneficial effects on bone mass in women with osteoporosis? What are common side effects?
- Calcitriol
| - Hypercalcemia and hypercalciuria
123
Which type of diet may increase bone loss?
- Low calcium
- Low vitamin D
- High phosphorus
- High protein
124
Which lifestyle factors may increase bone loss?
- Low physical activity
- Excess alcohol
- Caffeine
- Smoking
