Nutrition And Aging DLA Parts 1 & 2 Flashcards
Life expectancy is… population is…
Increasing
Changing
How is nutrition an important determinant of overall health at any age?
- Longevity
- Physical health
- Cognitive function
- Vitality
- Quality of life
Longevity and health is…
often influenced genetically but can be managed by healthy choices and pharmaceuticals
The process of growing older…
• Reduction in production of vital energy
• Decline in cellular activity causing a reduction in
cell number and mitochondrial activity
• Interruption in membrane transport processes
• Reduction in enzymatic activity (liver’s role in eliminating metabolic waste)
• Reduction in core body temperature
• Biological age vs. chronological age:
What are the benefits of lower energy requirements?
- Energy requirements drop between third and ninth decade of life, up to 33%
- Decline in muscle mass universal
- Physical activities can slow this decline
- Muscle more metabolically active than adipose
- Loss of muscle mass accompanied by drop in basal metabolic rate
- deceased. 10 kg = decreased 150 kcal/d energy expenditure
- Decline in energy requirements and consuming less food can lead to protein and micronutrient deficiencies
What factors contribute to inadequate nutrition socioeconomically?
Fixed Income
Reduced access to food
Social isolation
Inadequate storage facilities Inadequate cooking facilities
Poor knowledge of nutrition
Dependence on others Caretakers Institutions
What factors contribute to inadequate nutrition in older adults physiologically?
Impaired strength/aerobic capacity
Impaired mobility/dexterity (arthritis, stroke) Impaired sensory input (smell, taste, sight) Poor dentition/oral health
Malabsorption
Chronic illness (via anorexia, altered metabolism)
Alcohol Drugs (eg, SSRIs,a NSAIDs,b digoxin, opiates, levodopa, antibiotics, metformin, iron, others)
What factors contribute to inadequate nutrition in older adults psychologically?
Depression
Bereavement
Anxiety, fear, paranoia
Dementia
What factors contribute to inadequate nutrition in older adults?
Failure to monitor dietary intake and record weights
Failure to consider increased metabolic requirements
Iatrogenic starvation (eg, NPOc for diagnostic tests)
Delay in instituting nutritional support
What changes in body systems associated with aging?
Skeletal muscle atrophy, Osteoporosis
Atherosclerosis, hypertension
Reduced cognitive function
Reduced lung volume, Obstructive pulmonary disease Non-insulin dependent diabetes, hypercortisolemia General decline in function especially T cells
What are the age related changes in body composition?
Weight increases (body fat) steadily from age 30-60 y
• After 60 y,
• weight stabilizes then declines
• Loss is mainly lean body mass
• muscle mass may decline up to 45% by the eighth decade of life (sarcopenia)
• Causes? Decline in:
- Fat metabolism
- Activity
- Protein synthesis capacity
- Hormones (testosterone, estrogen and insulin-like growth factors)
- Mitochondrial ATP production
What is protein energy malnutrition?
Insufficient energy and/or protein for metabolic needs
PEM most common deficiency in elderly persons caused by:
Inadequate intake
• reversible
Disease affecting metabolism, composition & appetite
• Called cachexia and may develop in older persons with no obvious cause
• Cachexia associated with chronic disease (cancer, infection, etc.) • Acute immune response
• Elevated inflammatory mediators
• Affects hormone production, control of metabolism and increase in resting energy
expenditure
• Muscle degradation may not be reversible
What is the impact of chronic inflammatory response?
Normally innate immune response is regulated by negative feedback when infection or injury is resolved
• Older persons often have ongoing low- grade activation of inflammatory processes
• Measured by modest elevations of serum levels of inflammatory signaling proteins.
• Associated with poor outcomes of
disability, cognitive decline, frailty,
sarcopenia, and early mortality.
What is the relation of aging process and oxidative stress?
Cellular defenses against oxidative damage decline with age
Reductions in the expression of genes and proteins associated with mitochondrial function and reduction of free radicals
Increased expression of those involved with pro-inflammatory response (like cytokines)
What is the relation between the aging process and anemia?
• Anemia is common in elderly, prevalence increases with age (CBC) • Typical symptoms attributable to advancing age
• Fatigue, weakness, shortness of breath (dyspnea)
• A cause is found in ~80% of elderly patients
• Most common causes (check size and shape of RBC):
• Chronic disease
• Iron deficiency* due to chronic gastrointestinal blood loss (microcytic) • NSAIDinducedgastritis,ulcer,coloncancer,diverticula
• Vitamin B12 deficiency (macrocytic) • Folate deficiency (macrocytic)
* Iron supplementation should be smaller doses than for younger population
What’s the impact of Dysregulation of energy intake?
- Impaired regulation of food intake is common among healthy and frail people over 70 years of age
- Lowering of appetite and hunger signals in response to changes in energy demand
What are the causes of inadequate food intake in the elderly?
- Depression, social isolation and dementia • Pain and impaired movement
- Fatigue
- Poor dental health
- Swallowing dysfunction
- Loss of taste and smell
- Medications
- Low Income giving rise to Dietary restrictions
What is often associated with loss of appetite, smell and taste?
Loss of taste and smell common with advanced age Greater losses in taste and smell associated with:
• Zinc, niacin and vit B-12 deficiency
• Infections (upper respiratory tract, sinusitis)
• Dental problems
• CNS (dementia, Parkinsonism, MS, head trauma)
• Endocrine (diabetes, hypothyroidism)
• Medications (antidepressants, anti- inflammatories, anti-hypertensives, lipid lowering drugs)
What are the post operative effects on appetite?
Post-absorptive Effects on Appetite
Changes in the gut with advanced age
Stretch reflexes within wall of stomach may become overly responsive in old age
• Early satiety and reduced food intake
Gastric emptying delayed and may lead to • Slower absorption of carbohydrates
• Altered insulin secretion
• Suppression of hunger response
What is the under-nutrition carousel?
15-60% of patients admitted to hospital are undernourished—> Hospital
Longer stay
More infections
More support required post-discharge—> Up to 70% of patients discharged from hospital
weigh less than on admission—> Home
More GP visits
More hospital admissions—> 15-60% of patients admitted to hospital are undernourished
Whaat conditions are associated with frailty at or above 85?
• Functional decline • Falls and associated injuries (hip fracture) • Polypharmacy • Chronic disease • Dementia and depression • Social dependence • Institutionalization or hospitalization • Nutritional impairment
What nutrients need to be increased in the elderly ?
Protein*
Calcium Vitamin D Vitamin B12 Folate Vitamin A
What nutrients are decreased in requirements for the elderly?
Calories
Vitamin A* (decreased clearance)
What nutrients are decreased in requirements for the elderly?
Calories
Vitamin A* (decreased clearance)
What are the protein requirements in the elderly?
• Recommended daily protein intake 1.0-1.25 g/kg/d
• Protein required for nitrogen balance increases with decreasing energy
intake
• Disease states and medications can induce catabolic protein state
• Elderly confined to bed from injury, surgery, infection, acute inflammatory condition, chronic illness are at HIGH RISK of profound negative nitrogen balance
• Rapid loss of lean body mass – skeletal muscle
• Hospital patients warrant protein intake of 1.5 g/kg/d*
• High dose corticosteroids can cause profound negative nitrogen balance
Renal or hepatic insufficiency requires protein insufficiency
What is the role of fat and cholesterol to the elderly ?
Obesity common in older adults, up to 65 years old
• Fat and cholesterol restricted diets to prevent coronary heart disease
(#1 cause of death for this group)
Controversial: Fat and cholesterol restricted diets after age 65 may not have any beneficial effects
• Detrimental to frail older individuals
• Detrimental to those struggling to maintain weight
Obese individuals: Increasing ratio of mono-unsaturated/poly-unsaturated fats may be beneficial rather than restrict
30% of diet, never to fall below 10% of total energy requirements
• Minimum requirements for essential fatty acids and transport of lipid soluble vitamins (A, D, E, K)
What is the role of carbohydrates in elderly?
- Required amount is calculated by default
- Total energy, protein and fat required should be determined first • Minimum 50-100 g of complex carbohydrates per day
- Selections should be rich in fiber
What is the role of water in the health of the elderly?
• Adults > 65 y are more likely to become dehydrated • Lower intensity of thirst response
• Chronic disease and injury further alter perception of thirst • Life-threatening dehydration can develop rapidly
• Highest risk for those with diarrhea, fever, poorly controlled diabetes, those on
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diuretics or laxatives
What is the role of fiber in the health of the elderly?
• Dangers of low-fiber diet include constipation and diverticulosis
• 50% adults 60-80 years old suffer diverticulosis, nearly 100% after 80
years of age
• Water insoluble fiber holds water within intestinal contents • Increased fecal bulk, decreased gut transit time
• Reduces constipation and prevents colon diverticula
• Water soluble fiber increases viscosity intestinal contents
• Decreases rate of small intestine absorption of:
• Carbohydrates slowing down surge in serum glucose after meals
• Bile acids which may lower total cholesterol and LDL cholesterol 3-10%
What is the role of vitamin B12 (cobalamin) deficiency in elderly?
• Low serum B-12 levels affect 10-15% older adults
• Most common cause in elderly is malabsorption of cobalamin from food
• Often due to atrophic gastritis (chronic inflammation of stomach mucosa) & hypochlorhydria (reduced gastric acid secretion)
more about this in DM module where we introduce the Intrinsic Factor (IF)
• Deficiency often will present as:
• Neurological
• Peripheral neuropathy – paresthesia and numbness
• Spinal column lesions – loss of vibration and position sense, sensory ataxia, limb weakness • Neuropsychiatric
• Hematological (often late finding) • Megaloblastic anemia
• Patients with symptoms should receive parenteral supplementation (several intramuscular injections 100-1000 μg)
What is the impact of folic acid deficiency in the elderly ?
• Associated with general malnutrition, alcohol abuse, prescribed medications which are folate antagonists (methotrexate, phenytoin, sulfasalazine)
• Can present as a megaloblastic anemia
• In patients with normal B12, high folate associated
with protection from cognitive impairment • Memory and depression
• Folate status assessed by:
• Measuring serum folate if diet has not recently changed • Measuring RBC folate levels if recent change in diet
• 400 ug/d is recommended daily allowance
How does bone health change as we age?
Approximately 8% bone mass is lost every 10 years Osteopenia (loss of bone mass) common in older adults
• Demineralization through loss of calcium • Decreased rate of collagen synthesis
2 common types often coexist in older adults
• Osteoporosis has multifactorial causes
• Degeneration of already constructed bone - brittle
• Osteomalacia from inadequate calcium absorption and vitamin D deficiency • Abnormality of the building process - soft
What is osteomalacia ?
Osteomalacia from inadequate calcium in diet
• Older adults often fail to consume the required 1500 mg/d
• Calcium absorption declines with age
• Calcium bioavailability from vegetables is limited (phytochemicals may interfere with absorption)
• Most seniors require supplementation
• Many forms of calcium fortified foods (some brands orange juice) • Calcium citrate better absorbed than calcium carbonate
What is the impact of vitamin D absorption for calcium absorption? What is the impact of this on the elderly?
Vitamin D required for calcium absorption
• Vitamin D3 is made naturally from sunlight
• As we age, our skin begins to lose some ability to synthesize vit D3 • Confinement reduces vit D synthesis (reduced exposure to sunlight)
• Vitamin D from the diet must be converted to the active form in the kidney • As we age, the amount of kidney tissue decreases (next)
Most seniors require supplementation (daily, weekly, quarterly) • 1998 daily DRI recommendations
• 5 μg for those 31-50 y, 10 μg for those 51-70 y and 15 μg for those >70 y
• Early symptoms of vitamin D deficiency;
• Non-specific musculoskeletal pain (back, hips, legs and shoulders)
• Proximal leg weakness
Describe the aging kidney
Atrophy: 1/3 decreased mass by age 80
Decreased blood filtration, reabsorption and secretion
Many medications to treat common diseases associated with getting older can become very damaging to the kidney as one approaches advanced age
What is the use of nephrotic medications in the elderly?
Non-steroidal anti-inflammatory drugs reduce vasodilatory prostaglandins leading to narrowing of the blood vessels
• reduces blood flow to kidneys and potentially cause kidney damage
Blood pressure medications
• ACE inhibitors protect kidney from diabetic induced kidney damage, yet can be nephrotoxic in the elderly
• Diuretic damage Antibiotics
• Gentamicin, polymyxin E, rifampin and vancomycin can damage kidney cell membranes
Blood glucose lowering
• Metformin not to be prescribed for the kidney impaired
What are the signs and impact of lower vitamin A clearance?
Supplementing Vitamin A is important
Some evidence that vitamin A clearance from peripheral tissues may decrease in older adults
Signs of excess include: • Headache
• Lack of energy
• Anorexia
• Reduced white blood cell count • Impaired hepatic function
• Bone pain with hypercalcemia
