Elderly Flashcards
Senescence
Physiological changes during the adult years: Often termed “normal aging”
Cell cycle arrest in which cells cease to proliferate –> decline in organ function and physiological function
Caused by cellular damage (DNA lesions, mitochondrial dysfunction, and inflammation)
Associated with ↑ chronic disease risk
Diet associations with reducing chronic disease
Fruit and veg intake: ↓ chronic disease, ≥ 5 servings/day –> 23% lower risk of premenopausal breast CA
Olive oil (med diet)
↑ risk with: High in saturated fat, alcohol, Na, sugar and low in fiber
Lifestyles: smoking, little exercise and high stress
Physiological changes ages 20-35
Lean body mass changes, 3-5% loss per decade without activity
Protein synthesis decreases with aging + no change in protein degradation.
- Muscle turnover and repair likely decreased with age
- High physical activity + well balanced diet can minimize loss of LBM
Bone mass loss begins at age 34 due to: ↓ estrogen (M+F) and ↓ testosterone
- influenced 20-40% by diet/exercise
Physiological changes 50-69 years
Catabolism > anabolism, ↓ muscle mass ↓ BMR and ↓ caloric needs
- easy and average weight gain until 70s
- can be prevented/slowed down by physical exercise
↓ growth hormone production
↓ estrogen changes BMD
↓ testosterone, reduced protein store maintenance
↑ fat mass by nearly 2x
↓ organ mass, GI cells, glomerular filtration, etc
Sarcopenia
Risks of LBM loss
Intervention against sarcopenia
Sarcopenia = age-related loss of muscle mass, strength + function
↑ Adipose tissue –> ↑ low grade inflammation –> ↓ muscle protein metabolism + function
↓ Muscle mass –> ↑ CVD mortality (CVD, diabetes, dementia)
- Men with similar levels of muscle loss are more at risk than women
Resistance training is an effective intervention against sarcopenia
Overweight and obesity in elderly 65+
80% overweight, 40% obese
↑ risk of: mortality, T2D, CVD, CA
Can coexist with sarcopenia which makes matters worse
Frailty definition and classification
Progressive age-related decline in physiological systems
Classification: Poor performance in three out of the following: muscle weakness, slow walking speed, exhaustion, low physical activity levels, or unintentional weight loss
high fall risk, death within several years of fall/hospitalization
Associated with high fat mass, low muscle mass, and high waist circumference
Unintentional weight loss concerns
Causes
Significant weight loss defined as 5% loss in 1 month and 10% in 6 months –> increases mortality rates
Weight loss in older adults with BMI under 30 has higher mortality risk than not losing weight (better to not lose weight)
Causes: cachexia (muscle + fat wasting), inadequate intake, anorexia, muscle atrophy (sarcopenia)
Changes in organ functions with aging
Taste
Mouth and throat
Stomach
1) ↓ taste buds, ↓ appetite –> poor food intake
- prescribed diets can worsen palatability
2) ↓ salivary secretions –> xerostomia from drugs/diseases which ↑ risk of infections
3) ↓ esophageal function. Dysphagia –> CNS diseases, choking risk, risk of pneumonia
4) ↓ gastric function, ↓ gastric acid from parietal cell mass ↓, ↓ commensal bacteria
- ↓ 25% pepsin –> ↓ proteolysis (B12/ IF)
- ↓ nutrient absorption from hypochlorydia overgrowth of bacteria and dyspepsia (ulcers)
Changes in organ functions with aging
Liver
Pancreas
Intestines
Kidneys
5) ↓ liver function, ↓ bile, ↑ food intolerances, ↓ drug metabolism and ↑ drug toxicity
6) ↓ Pancreatic secretions –> ↓ nutrient absorption
7) Change in intestinal morph - ↓ function, ↑ diarrhea, constipation and lactose intolerance
8) Change in renal morph - loss of 25% by 60, ↓ capacity to excrete wastes from protein, electrolytes, drugs, vitamins
- ↓ ability to bioactivate vit D –> deficiency
- ↑ risk of dehydration from ↓ thirst mechanism
Risk factors for elderly
1) ↑ risk of malnutrition –> ↓ absorption
2) Chronic diseases risk
3) Multiple medications interactions or polypharmacy
- > 65% of elderly use >1 drug daily to treat a medical condition
4) Physical disabilities and recovery from surgery/infection
↓ Abilities to procure and prepare food
5) Tooth loss or oral pain - less effective chewing and risk of choking
- 70% of elderly in Canada have partial or full dentures
6) Poor eating
7) Economic hardship high rate of 20%
8) Reduced social contact - depression, social isolation
Food deserts
Geographic areas, especially rural or impoverished urban locations, lacking accessible supermarkets or grocery stores
Often have to shop at convenience stores
- Limited or no access to fresh fruits and vegetables
- Products usually much more expensive
Bone remodeling
Osteoblasts
Osteoclasts
Bone remodeling: replacement of old bone with newly synthesized bone tissue
Osteoblasts = synthesize bone matrix
Osteoclasts = dissolve bone minerals with acids to digest bone matrix + phagocytes to digest protein
Type I vs. Type II osteoporosis
Type I: onset ages 50-70
- ↑ osteoclast activity and rapid bone loss due to ↓ estrogen/testosterone in women/men
- hormonally related or ovarian dysfunction or anorexia nervosa
Type II: Senile (age-related) osteoporosis, cortical (outer) bone loss due to osteoblast under activity
- from age 40 and slow and steady decline
- associated with ↓ 1,25(OH)2D3 prod
Osteoporosis
Osteoporosis = reduced bone of normal composition
Bone density < 2.5 SD below young people
Low bone mass, deterioration of bone tissue, disruption of bone structure, compromised bone strength
- Increased mortality associated with hip and vertebral fractures –> not diagnosed until fracture (“silent”)
Bone loss speeds up during menopause due to ↓ estrogen production: 3-5% annually
- tapers off after 60
Higher peak bone mass ↓ risk of developing osteoporosis
Estrogen dampens the bone resorbing effects of PTH when there is a ↓blood Ca
Lower estrogen:PTH ratio during menopause –> PTH can mobilize Ca more readily from bone
