Osteoporosis

Cassidy Shumway, Grace Pineda, Elaine Parry,

Amber Smith

What is Osteoporosis?

● “Osteoporosis is a chronic, progressive disease characterized by reduced bone mass and microarchitectural deterioration of bone, involving an extensive fragility and a subsequent increase in fracture risk”

● Often referred to as a “silent disease”

Physiology

PhysiologyTrabecular Bone● Cancellous or spongy bone● 20% bone composition● Knobby ends● Less dense● Fractures

Cortical Bone● Compact bone● 80% bone composition● Shafts

Bone Anatomy

Bone CompositionComponents that strengthen bone

● Collagen fibers○ Fibrous protein arranged in long strands or bundles

● Calcium and phosphate salts○ Contributes to hardness, rigidity, and compressive strength

● Hydroxyapatite

Bone CellsOsteoblasts● Form/produce bone tissue● Mesenchymal stem cells

Osteocytes● Come from osteoblasts● Mature permanent bone cells

Osteoclasts● resorption/breakdown of bone● Hematopoietic stem cells● Come from immune system

BoneBone Mass Density (BMD)● Mass of mineral per volume of

bone● Doesn’t give information on

structural quality of bone

Peak Bone Mass (PBM)● Max amount of bone tissue

person has● Reached by 30 years old● Genetics, nutrient intake,

physical activity

CalculationsBone Area (BA)

● Length x Width● cm^2

Bone Mineral Content (BMC)

● Measured in grams● PBM

Bone Mineral Density (BMD)

● Mass of mineral/volume of bone

● g/cm^2

Bone Modeling● Skeleton growth until mature height is reached● Formation > Remodeling

● Females: 16-18● Males: 18-20

Bone RemodelingOsteoclasts resorb bone and osteoblasts reform it

Regulated by: PTH, calcitriol, growth hormone, etc

2 Stages:

1) Initiation: Preosteoclastic cells activated and move to surface to mature into osteoclasts

2) Rebuilding/Formation: Osteoblasts secrete collagen and matrix proteins

Bone Remodeling

Pathophysiology

Pathophysiology

Combination of injury and increased bone fragility

Reduced Bone Mass

PathophysiologyGlucocorticoids

● Decreased osteoblast activity→ increase bone resorption

● Reduce bone quality● Disrupt microarchitectural

integrity● Problem for young individuals

with long-term use● GIOP

Pathophysiology

Genetics● Strong genetic component● High heritability of BMD● Genes interactions with diet and exercise

CLCN7 Osteoclast chloride channel

TCIRG1 Osteoclast proton pump

CATK Degrades bone matrix

RANKL + RANK Essential for osteoclast differentiation

Diseases Associated with Osteoporosis

Prevalence / Incidence● 54 million Americans have osteoporosis or low bone mass● 1 in 2 women and 1 in 4 men aged 50 and older will break a bone due to

osteoporosis● Osteoporosis is responsible for 2 million broken bones and $19 billion in

related costs every year (53 million per day)● Ethnicity: Caucasian, Asian, and Hispanics women at greater risk than

African Americans● By 2020, 25% of the population will be people older than 65 years of age. As

result, incidence of osteoporosis will most likely increase

Etiology

Estrogen-androgen Deficient Osteoporosis

● Considered to be “primary” osteoporosis since it results from the involutional losses associated with aging and additional losses related to menopause.

● Occurs in women within a few years of menopause from a loss of trabecular bone tissue and cessation of ovarian production of estrogen.

● Low estrogen levels may lead to increased bone decay and osteoporosis. Estrogen aids in regulating osteoblasts, which are responsible for building new bone. When estrogen levels drop, fewer cells are produced and bone is lost, but not replaced.

● Can be prevented by adjusting hormone levels as soon as possible.

Effects of Estrogen Levels on Bone Cells

Secondary Osteoporosis* Can be described as bone loss that occurs due to exacerbated disorders or medication exposures.Results when an identifiable drug or disease process causes loss of bone tissue. Such as:

● Chronic diarrhea/intestinal malabsorption (including celiac disease)● Chronic obstructive lung disease● Chronic renal disease● Diabetes● Hemiplegia (paralysis of one side of the body)● Hyperparathyroid disease● Hyperthyroidism● Subtotal gastrectomy

Secondary causes are commonly found in premenopausal women and men with osteoporosis.

Fun Fact: about 64% of those who suffer from secondary osteoporosis are men.

Risk Factors● Age (especially older than age 60)● Amenorrhea (absence of period) in women as a result of excessive exercise

(athlete triad)● Androgen depletion with hypogonadism in men● Cigarette smoking● Estrogen depletion from menopause or early oophorectomy (the removal of

one or both ovaries).● Ethnicity: white or Asian● Excessive fiber intake (may interfere with calcium absorption).● High Acid/ Alkaline Diets (may increase calcium excretion and have a

detrimental effect on bone).

Risk Factors Cont.● Excessive intake of alcohol, caffeine● Female gender● Family history of osteoporosis or parental history of hip fractures● Inadequate calcium or vitamin D intake● Lack of exercise● Prolonged use of certain medications● Sarcopenia (loss of muscle tissue due to the aging process)● Underweight, low BMI, low body fatness: lower than 127.5 lbs is a risk factor

for low bone mass.● Genetic diseases: Marfan syndrome, porphyia, homocystinuria, Gaucher

disease, cystic fibrosis, glycogen storage disease, Ehlers-Danlos, hemochromatosis

Diagnosis

Diagnosis● Vertebral Imaging● Quantitative Ultrasound (QUS) - heel scan● Quantitative Computed Tomography (QCT)● Drastic height loss → > 1.5 inches● Detailed medical history and physical exam● Fractures → hip and spine● Biochemical markers● BMD Testing → DXA

Vertebral Imaging + Height Loss

ImagingDowagers Hump

ImagingLordosis● Excessive inward curve of spine

Biochemical MarkersDoesn’t show bone health

Bone Formation Markers● BSAP, OC, PINP● Osteoblast activity● OC good biomarker for steroid-induced osteoporosis

Bone Resorption Markers● CTX, NTX● By-products of osteoclast activity

QUS

QUS● Doesn’t directly measure BMD● Measures speed of sound and broadband ultrasound attenuation● Peripheral sites● Predicts fracture risks

○ Postmenopausal women + men > 65

QCT● Measures trabecular and cortical bone density at spine and hip● Determines bone strength● QCT of spine can predict vertebral fractures

Bone Mineral Density TestingDXA● Hip and spine density● Measures bone loss● Confirms diagnosis

Lower bone density = greater risk of fracture

BMD TestingWho Should be Tested?

● Postmenopausal women with 1+ risk factors● Women > 65● Women who have gotten hormone-replacement therapy for extended time● Men + women with hyperparathyroidism● Men + women receiving long-term glucocorticoid therapy

DXA Images

T-Scores● Your bone density compared to what

is expected in a healthy young adult of your gender

● Postmenopausal women + men > 50

Z Score● Compares your bone density to average bone density of people your age and

gender

● Women menstruating

● Men < 50

● Teenagers and children

● Z-Score < -2.0 = “below expected range for age”

● Z-Score > 2.0 = “within expected range for age”

Medical Management

Medications

● Most osteoporosis medications can be used to prevent and treat it● Estrogen Replacement Therapy is not used to prevent osteoporosis

○ Bisphosphonates○ Hormonal Therapy

■ Calcitonin■ Teriparitide (anabolic agent--stimulates osteoblasts)■ Estrogen Replacement Therapy

○ RANKL Inhibitor

Bisphosphonates

● Inhibit osteoclasts to reduce bone resorption● Stop medications after 2-3 years● Slower, but longer lasting increase in BMD● Side effects: esophagitis, gastritis, dysphagia, renal dysfunction

○ Alendronate Sodium○ Risedronate Sodium○ Zoledronic Acid○ Etidronate○ Ibandronate

Hormones

● Calcitonin● Teriparitide● Estrogen Replacement Therapy

Calcitonin

● Hormone produced by the thyroid gland● Blocks effects of PTH

○ Inhibits osteoclastic bone resorption● Side effects: rhinitis, epistaxis, anaphylaxis in people allergic to salmon

Teriparitide

● Teriparitide (Forteo)○ Recombinant portion of Parathyroid Hormone

● Increases osteoblast number and function○ Anabolic medication

● Prescribed first, then bisphosphonates○ Increase in bone mass from Forteo, then antiresorptive therapy

● Side effects: leg cramps, nausea, dizziness

Estrogen

● Hormone produced that travels throughout the body to estrogen receptors● Stimulates bone, breast, vaginal, uterine, central nervous system, and lipid

tissues● People on estrogen therapy were at a higher risk for breast and uterine

cancers

Estrogen Replacement Therapy (ERT)

● Raloxifene (Evista)○ Estrogen agonists/antagonists (SERMs)○ Stimulate estrogen receptors in bone tissue○ Side effect of hot flashes

● Tissue Specific Estrogen Complex○ Estrogen agonist/antagonist (bazedoxifene) AND conjugated estrogen○ Make the effects of the agonist/antagonist even more specific

ERT Side Effects

● When medicine is stopped, in 3-5 years BMD values are back to baseline● Side effects: heart attack, stroke, breast cancer, pulmonary emboli, deep

vein thrombosis, weight gain● Use the lowest dose for the shortest time

RANK-Ligand Inhibitor

● Receptor Activator of Nuclear Factor k B inhibitor○ Denosumab

● Inhibits a cellular signaling pathway that increases osteoclast activation● When medications are stopped, BMD values return to baseline● Side effects: hypocalcemia, cellulitis, skin rash

Hip FracturesFall and break or break then fall?

● Both can happen● If bones are weak, it could be break then fall● If elderly, a hip fracture could occur from

falling

Surgery

● Always recommended● Should happen as close to the time of the

accident as possible● Younger patients normally have internal fixation● Sliding hip screw is better than multiple screws

Post-operation

● Functional Lengthening○ Leg lengths could be different, but will normalize after 3 months

● Discharged from hospital 5-7 days afterward● Caution for 6 weeks after surgery● Improved quality of life after having a hip replacement

Post-operation● Physical Therapy

○ Walking○ Stairs○ Controlled movement○ Increase range of motion○ Muscle power

● Exercise○ Strengthens muscles and joints○ Decreases risk of blood clots

● Adequate protein, Vit A, Vit C, Iron and Zinc for wound healing● Put kitchen items at waist level and within easy reach ⭐

Reducing risk of falls● EXERCISE● Exercise + vision assessment and

treatment● Wear Hip Protectors● Use a cane● Install grab bars around the house● Have well-lit areas

● Keep floors free of clutter● Use a bag to keep hands free● Don’t drink alcohol● Don’t be rushed● Clean up spills● Wear appropriate shoes● Mark top and bottom stairs with

bright tape

Nutrition and Bone/MNT

Importance of Calcium● Bone consists of an organic matrix of collagen fibers and salts of calcium

and phosphate that develop into crystals of hydroxyapatite● The hardness of the hydroxyapatite helps give bone strength● Calcium is not made in the body and therefore comes from foods we eat● Body stores 99% of its calcium in the bones and teeth ● The last 1% is serum calcium which is essential for muscle contraction,

nerve impulse secretion, blood coagulation, and normal cardiac function● Serum calcium is NOT an indicator of calcium status

Calcium HomeostasisSerum calcium concentration is regulated by calcium-regulating hormones: parathyroid hormone (PTH) and 1,25 dihydroxy vitamin D3 (calcitriol), and Calcitonin

PTH increases reabsorption from the kidney and bone and calcitriol increases gut absorption and initiates osteoclastic activity for bone breakdown

Inadequate intake of calcium can cause calcium to be pulled from the bones which decreases bone mass density (BMD)

Calcium can NOT be absorbed in the body without adequate vitamin D

Calcium Recommendations● Best way to meet recommendations is through consuming high calcium

containing foods○ Dairy sources are primary source due to high calcium content, high absorptive rate, low cost

to purchase, and common○ calcium can be consumed through non-dairy sources as well

● Evidence suggests that the average American does not meet recommended daily calcium intake

● Those who do not obtain enough calcium through food should take supplement to meet those guidelines

Calcium UL: 2500-3000 mg/day

Calcium-rich foodsDairy

● Cheese, Yogurt, Milk products

Non-Dairy

● Calcium-fortified juices, cereals, breads, rice milk, or almond milk

● Canned fish (sardines, salmon with bones)● Soybeans, soy products (tofu made with calcium

sulfate, soy yogurt, tempeh), and some other beans

● Some leafy greens (collard and turnip greens, kale, bok choy)

● Foods high in oxalate and phytate can reduce the absorption of calcium in those foods .

○ Ex. spinach, rhubarb, beet greens, navy beans, legumes etc.

Amount of calcium in foodsAmount of calcium in foods varies with brand, serving size, and fortification

When reading Nutrition Facts label, multiply daily value (DV) % by 10 to determine mg’s per serving.

For example: 20% DV equals 200 mg of calcium

“Excellent” sources = more than 200 mg/serving

“Good” servings = 100 to 200 mg/serving

Calcium Supplementation● Calcium Carbonate- most common, take

with food because acidic environment enhances absorption. Optimal when taken in doses of 500 mg or less

● Calcium Citrate- more common to be taken by seniors with achlorhydria

● Avoid eating foods high in oxalate and phytate when taking supplements

● Be mindful of UL of around 2500-3000 mg/day depending on age

Potential Barriers to adequate calcium intake

● Lactose Intolerance● Milk Allergy● Cow’s milk: Good or bad?

Lactose Intolerance● Most individuals manufacture some lactase, but just can’t handle a 200 ml load● Consuming lactose-containing foods in conjunction with a meal appears to decrease symptoms● Recommended to gradually increase small amounts of lactose-containing foods

○ Helps stimulate GI to increase production of lactase○ Determines maximum quantity that can be consumed at one time

● Consume dairy products with higher fat content○ Delays GI transit○ Possibly allows for longer time for lactase to be available during digestion

● Look into lactose-free specialty products ● Consume non-dairy calcium rich products● Supplement if needed

Cow’s milk allergy

● Occurs in 1-2% of children under 3 yrs. Of age, .2-.4% in general population

● Often seen to resolve in children● If doesn’t resolve, obtain calcium and

other nutrients from other sources● Supplementation

Cow’s milk: Friend or foe?

● Many people think that milk does more harm than good.

○ Ex. increase bone fracture, protein in milk increases calcium excretion, increases diseases etc

Studies show that cow’s milk is associated with slower bone turnover and higher BMD

Conflicting results if milk increases bone fracture or not

Importance of Vitamin D

● Vitamin D’s main function is to maintain serum calcium and phosphorus levels within constant range

● Stimulates intestinal calcium and phosphorus transport● Stimulates osteoclast activity in bone● May have role in muscle tone and fall prevention● Improves Bone Mass Density (BMD)

Vitamin D Status● Vitamin D status depends mostly on sunlight and secondarily on dietary

intake● Vitamin D deficiency is a concern with older population

○ Due to thinner skin that contains fewer cells to synthesize vitamin D, decreased renal function, decrease estrogen, and decrease of vitamin D to active form

● Common foods with vitamin D: egg yolks, fatty fish such as salmon, tuna, mackerel, cod liver oil, fortified milk and cereals, and some mushrooms.

Vitamin D RDA Recommendations

● The elderly and those being treated with bone drugs may be recommended to 800-1000 units/day

● Older adults who are frail or institutionalized may need up to 2000 IU/day● Adults with deficiency treated with 50,000 per week for 8-12 weeks w/

maintenance of 1,500-2000 IU/day (varies)

Males Females RDA UL

1-3 yr. 1-3 yr. 600 IU/day 2500 IU/day

4-8 yr. 4-8 yr. 600 IU/day 3000 IU/day

9-30 yr. 9-30 yr. 600 IU/day 4000 IU/da

30-50 yr. 30-50 yr. 600 IU/day 4000 IU/day

50-70 yr. >50 yr. 600 IU/day 4000 IU/day

>70 yr. >70 yr. 600-800 IU/day 4000 IU/day

Vitamin K ● Vitamin K● Osteocalcin is a vitamin-k dependent protein and is produced by osteoblasts ● Active osteocalcin binds to calcium ions and incorporates them into

hydroxyapatite crystals that form bone matrix ● After bone resorption (breakdown), osteocalcin is released and enters blood● Serves as a serum bone marker

○ Deficiencies in calcium and phosphorus lower the formation of hydroxyapatite crystals which make free osteocalcin to circulate in the blood

Other important nutrients to bone health● Phosphorus

○ Body’s reserve of phosphorus is found in bone as hydroxyapatite○ Phosphate is largely found in meat○ Calcium and Phosphorus intake need to be balanced

● Trace minerals○ Iron, zinc, copper, manganese, and boron may help prevent bone loss○ However, not well established

● Protein○ Adequate protein intake with adequate calcium intake is needed for bone health○ Protein may improve calcium absorption○ Help provide structural matrix of bone○ Protein 1.0-1.5 g/kg-General Recommendation○ Higher intake may be advised with cases of negative nitrogen balance

■ Ex. surgery, fractures

Be careful with excess intakes!

● Sodium○ High sodium intake can increase calcium excretion○ No adverse effects when there is adequate calcium and vitamin D intake

● Dietary Fiber○ Excess fiber from foods that contain phytates or oxalates may lower calcium absorption

● Caffeine and soft drinks○ Primary issue is that is replaces dairy beverages○ Potential direct effect

Nutrition Assessment● Anthropometrics

○ Height, weight, BMI, weight history, age○ Low body weight considered risk factor○ Overweight is protective in comparison

● Biochemical○ Evaluate calcium, vitamin D, protein, vitamin K, and trace mineral lab

values○ CBC, renal function test, liver function test, and hormone level tests○ Biochemical bone markers: Serum C-telopeptide (CTX), serum

procollagen type 1 N-terminal propeptide (P1NP), Osteocalcin, BSAP

Nutritional Assessment● Clinical

○ Curvature of back○ Posture changes○ Current medications/history- some interfere with calcium absorption,

promote calcium loss from bone, or cause nutritional side effects● Dietary

○ Obtain diet history on intakes/habits○ Excess of some nutrients can interfere with calcium absorption

■ Sodium, dietary fiber○ attitude /feelings on dairy○ Alcohol and cigarettes

Nutritional Assessment● Functional

○ Is patient immobile (confined to bed, or unable to move freely?)○ Immobility may contribute to bone loss

● History○ Family history- genetics may contribute 50-80% of BMD○ Menopause or amenorrhea- can accelerate bone loss○ Does patient have any other chronic disease/condition?

Alternative Therapy: Chinese Herbal Medicine● Used widely in China to treat primary osteoporosis

○ Traditional Chinese Medicine believes the health of the skeleton is closely related to health of kidney meridian and chinese herbal medicine is use to improve flow of Qi.

● CHM are products made from any part of medicinal plants (leaves, stems, buds, flowers, or roots).○ Some non-plant based components include insects, deerhorn, snake,

various shells and powdered fossils.● Can be taken by mouth, as capsules, tablets, liquids, or injections. ● Findings indicate that some studies show improvement while others don’t.

Chinese herbal medicine is still uncertain and more rigorous studies are needed.

Prevention

● Doing weight-bearing activity 3-5 times per week and resistance exercise 2-3 times per week with moderate to high bone-loading force (30-60 min./week).

● A diet adequate in calcium and vitamin D, and a balanced diet of low-fat dairy, fruits, and vegetables.

● The National Osteoporosis Foundation (NOF) recommends a higher intake of vitamin D to those who are 50 years and older (800-1000 IU/day).

● Consuming a diet lower in sodium, since it increases calcium excretion, is recommended for optimal bone health for women.

Case Study

Case Study: Nutrition Assessment● Anthropometrics

○ Current Ht: 5’3”, Wt: 113 lbs (51.4kg), IBW: 115lbs (52.3kg), BMI: 20, 73 years old

● Biochemical○ Extremely low vitamin D: 11 ng/mL (normal range is 30 to 75 ng/mL)○ Other lab values normal

● Clinical○ Right hip fracture○ T-score -3.5○ Curvature in upper thoracic and lower spine○ Medication: Forteo (teriparitide)

■ Increase bone formation

Case Study: Nutritional Assessment● Dietary

○ Low calorie intake○ Afraid of dairy (thinks its fattening)○ Lack of exercise

● History:○ Menopause in early 50’s○ Two years ago sister was diagnosed with osteopenia

Diagnosis

PES Statement:

Increased calcium and vitamin D needs related to severe osteoporosis as evidenced by low 25-OHD lab value, lack of dairy intake, sun exposure and exercise.

Diet Plan:Calories: 25-30 kcal/kg/day: 1275-1542 kcalProtein: 1.2-1.5 g/kg: 61.7 g. -77.1 g.Fluid needs: 1540- 1800 mL

Supplement:Vitamin D: 800-1,000 IU/dayWill try to get adequate calcium in diet first

● Provide education to her about being able to meet calcium needs through low-fat options.● Provide education on calcium-rich food sources● Encourage plenty of sunlight

1-Day Sample Diet● Breakfast

○ Scrambled eggs-2 eggs- 81 mg○ Milk (vitamin D&A fortified)-8 fl. Oz- 284 mg○ Cheerios-1 cup- 112 mg○ ½ banana- 3 g

● Morning snack○ Apple, medium -1- 11 g○ Low-fat vanilla yogurt - 110 mg

● Lunch○ Kale -1 cup- 53 mg○ Spinach-1 cup- 24 mg○ Shredded carrots-½ cup- 3 mg○ Low-sodium Chickpeas-⅓ cup- 28 mg○ Cucumber-½ cup- 5 mg○ Craisins-1/4 - 0 mg○ Grilled Chicken - 2.5 oz.- 4 mg ○ Ranch dressing - 2 TBSP- 8 mg

● Afternoon Snack○ Plum- 4 mg○ Orange juice (w/ vit. D)-1.5 cup - 523 mg

● Dinner○ Lemon Grilled Salmon- 3 oz.- 0 mg○ Steamed Broccoli- 1 cup- 46 mg○ Whole grain brown rice- ½ cup- 0 mg

Total kcals: 1,500 kcals Protein: 68gVitamin D: 385 IU (the rest will be obtained through sunshine and supplement)Calcium: 1300 mg

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