(Relates to Chapter 64, “Focous on osteoperosis ,” in the textbook) Focus on Osteoporosis (Relates to Chapter 64, “Focous on osteoperosis ,” in the textbook)

Osteoporosis Chronic, progressive metabolic bone disease characterized by Porous bone Low bone mass Structural deterioration of bone tissue Increased bone fragility

OSTEOPOROSIS (Cont’d) At least 10 million people in the United States have osteoporosis One in two women and one in eight men over 50 will sustain an osteoporosis-related fracture

OSTEOPOROSIS (Cont’d) Eight times more common in women than men for several reasons Lower calcium intake than men Less bone mass because of smaller frame Bone resorption begins earlier and accelerates after menopause

OSTEOPOROSIS (Cont’d) More common in women than men (cont’d) Pregnancy and breastfeeding deplete woman’s skeletal reserve of calcium Longevity increases likelihood of osteoporosis; women live longer than men

Etiology and Pathophysiology Risk factors Female gender Increasing age Family history White or Asian ethnicity Small stature Early menopause Excess alcohol intake

ETIOLOGY AND PATHOPHYSIOLOGY (Cont’d) Risk factors (cont’d) Cigarette smoking Anorexia Oophorectomy Sedentary lifestyle Insufficient calcium intake Low testosterone levels in men

ETIOLOGY AND PATHOPHYSIOLOGY (Cont’d) Peak bone mass is achieved before age 20 Peak mass determined by heredity, nutrition, exercise, and hormone function Bone loss after midlife is inevitable but rate of loss is variable

Normal vs. Osteoporotic Bone Fig. 64-10

ETIOLOGY AND PATHOPHYSIOLOGY (Cont’d) In osteoporosis, bone resorption exceeds bone deposition Occurs most commonly in spine, hips, and wrist Many drugs can interfere with bone metabolism

ETIOLOGY AND PATHOPHYSIOLOGY (Cont’d) Diseases associated with osteoporosis Intestinal malabsorption Kidney disease Rheumatoid arthritis Hyperthyroidism Chronic alcoholism Cirrhosis of the liver Hypergonadism Diabetes mellitus

Clinical Manifestations Often termed the “silent disease” because there are no symptoms Since no symptoms, the usual first signs are back pain and spontaneous fractures

CLINICAL MANIFESTATIONS (Cont’d) Manifestations include Sudden strain Fractures Back pain Loss of height Spinal deformities

Diagnostic Studies History and physical exam Bone mineral density (BMD) Quantitative ultrasound Dual-energy x-ray absorptiometry (DEXA)

DIAGNOSTIC STUDIES (Cont’d) Osteoporosis is a BMD of at least 2.5 standard deviations below that of a young adult BMD Osteopenia is more than normal bone loss but not yet at the level of osteoporosis

Collaborative Care Focus on proper nutrition, calcium supplements, exercise, prevention of fractures, and drugs Prevention and treatment depend on adequate calcium intake Increased calcium prevents future loss but will not form new bone

COLLABORATIVE CARE (Cont’d) Good sources of calcium Milk Yogurt Turnip greens Spinach Cottage cheese Ice cream Sardines

COLLABORATIVE CARE (Cont’d) Poor sources of calcium Eggs Beef Cream cheese Poultry Pork Apples and bananas Potatoes and carrots

COLLABORATIVE CARE (Cont’d) Supplemental vitamin D may be recommended Exercise should be encouraged to build up and maintain bone mass Patients should be instructed to quit smoking or cut down on alcohol intake to ↓ losing bone mass

COLLABORATIVE CARE (Cont’d) Calcium intake Premenopausal 1000mg/day Postmenopausal 1500 mg/day Supplemental vitamin D Sunshine Supplemental (800 iu/day)

COLLABORATIVE CARE (Cont’d) Drug therapy Estrogen replacement after menopause Calcitonin Bisphosphonates inhibit osteoclast-mediated bone resorption (e.g., etidronate (Didronel), alendronate (Fosamax)

COLLABORATIVE CARE (Cont’d) Drug therapy (cont’d) Selective estrogen receptor modulators Raloxifene (Evista) Teriparatide (Forteo) Portion of parathyroid hormone First drug to stimulate new bone formation