OsteoporosisHR. Siswosudarmo Department of Obstetric and Gynecology Faculty of Medicine GMU Yogyakarta

DefinitionOsteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissueConsequences: increased bone fragility and more susceptible to fractureBone mass density:Osteopenia: BMD is 1-2 SD bellow the young adult mean bone massOsteoporosis: BMD is 2-2.5 bellow the YAMBMDA decrease of 1 SD associated with 2X risk of fracture

Bone mass density and ageBMD decreases at the age 30 in woman and 45-50 in menMenopause dramatically accelerates bone mass loss in womenAfter menopause, 3% of BMD is lost per year for the first 5 year, and 1% thereafterPatient at risk for osteoporosis may lose up to 5% of BMD per year.Hip fracture account for 15% of total fracture but the effect (morbidity and mortality) is remarkable. Death in the first year following hip fracture is approximately 20%

Risk factorsRaceCaucasianAsianHispanicAfrican Americans (lowest)Family historyEstrogen deficiency (menopause)Thin, BMI < 22 kg/sqmLess exerciseSmokingExcessive use of alcohol and high caffeine intake

Primary and secondary osteoporosisPrimary: associated with decreased estrogen level in perimenopausal and menopausal women.Secondary: Associated with some risk factors including genetic disorders, hypogonadal states, endocrine disorders (hypogonadism, hyperparathyroidsm, hyperthyroidism, hyperglucocorticoidism, low growth hormon), gastrointestinal diseases (malabsorption syndrome), hematologic disorders, connective tissue disease, nutritional deficiencies, drugs, and a variety of other common serious chronic systemic disorders, such as congestive heart failure, end-stage renal disease, and alcoholism.

Mechanism of osteoporosisBone resorption exceeds bone formationCalcium loss is 15 mg/day or net loss 100 gTrabecular bone loss is greater than cortical bone loss (50% vs. 5%)Estrogen replacement therapy results in decreased bone resorption and decreased bone loss but doesnt stimulate new bone formationFracture of the vertebral body is the most common leading to a hunched postureHip, arm and rib fracture is often as a result of a seemingly trivial accident

Factors Involved in Building and Maintaining Skeletal HealthThe bone mass attained early in life, soon after adolescence is the most important determinant of skeletal health Factors contribute to bone mass development:Adequate nutrition and body weightExposure to sex hormones at pubertyPhysical activity

A balanced diet, adequate calories, and appropriate nutrients

Calcium intakes of 800 mg/day for children ages 3 to 8 and 1,300 mg/day for age 9 to 17, and 1,000 to 1,500 mg/day for older adults. High dietary protein, caffeine, phosphorus, and sodium can adversely affect calcium balanceVitamin D intake of 400 to 600 IU/day is recommended

Physical activityPhysical activity early in life contributes to higher peak bone mass Exercise during the middle years of life has numerous health benefits Exercise during the later years, in the presence of adequate calcium and vitamin D intake, probably has a modest effect on slowing the decline in BMD

Sex steroidsSex steroids secreted during puberty substantially increase BMD and peak bone mass Gonadal steroids influence skeletal health throughout life in both women and men Timing of menarche, absent or infrequent menstrual cycles, and the timing of menopause influence both the attainment of peak bone mass and the preservation of BMD Testosterone production in adolescent boys and men is similarly important in achieving and maintaining maximal bone mass Estrogens have also been implicated in the growth and maturation of the male skeleton

Growth hormoneGrowth hormone and insulin-like growth factor-I, which are maximally secreted during puberty, continue to play a role in the acquisition and maintenance of bone mass Growth hormone deficiency is associated with a decrease in BMD

DiagnosisLoss of height and change in posture Laboratory evaluation for secondary causes of osteoporosis Assessment of BMD (by dual X ray absorptiometry, DXA) especially from the hip, spine, and peripheral skeleton, and the T-score is at least minus 2.5 SD from young healthy white women Assessment of rate of bone remodelingBone pecific alkaline phosphatase and osteocalcin (bone formation)urinary levels of pyridinolines and deoxypyridinolines and serum and urine levels of type I collagen telopeptides (CTX and NTX) (bone resorption)

Potential osteoporosis peoplePatients receiving glucocorticoid therapy for 2 months or more Patients with other conditions that place them at high risk for osteoporotic fractureThe value of universal screening, especially in perimenopausal women, has not been established (750 BMD tests would be required to prevent just one hip or vertebral fracture over a 5-year period of treatment)

TreatmentAdequate calcium and vitamin D intake Physical activity Bisphosphonates: cyclic etidronate, alendronate, and risedronate Hormone replacement therapy (HRT) Selective estrogen receptor modulators (SERMs) such as Raloxifene Natural estrogens, particularly plant-derived phytoestrogens Calcitonin Nonpharmacologic interventions: improve strength and balance in the elderly, hip protectors to absorb or deflect the impact of a fall.

*15. OsteoporosisBlock 16, February 14, 2008 Week 3 International Programmedr. Risanto S., Sp.OG