Osteoporosi

OSTEOPOROSI

Osteoporosis affects approximately 13% to 18% of Amer-ican women aged 50 years and older, and another 37% to 50% have osteopenia, or low bone mineral density. Osteoporosis-associated fracture, especially of the hip and spine, are leading causes of morbidity and mortality, in-creasing in proportion to age. Osteoporosis is a largely preventable complication of menopause. Screening strate-gies and pharmacologic interventions are available to pre-vent and treat osteoporosis.

Bone mineral density (BMD) is an indirect measureof bone fragility. BMD is measured using dual-energy x-ray absorptiometry (DXA) of the hip or the lumbar spine. The results are expressed in standard deviations compared with a reference population stratified by age, sex, and race. The T-score is expressed as the standard deviation from the mean peak bone mineral density of a normal, young-adult population; and the Z-score is expressed as the stan-dard deviation from the mean bone mineral density of a reference population of the same sex, race, and age as the patient. Z- and T-scores are used for hip and spine mea-surements. The World Health Organization (WHO) de-fines a normal BMD T-score as >=−1. Osteopenia (low bone mass) is defined as a T-score between −1 and −2.5. Osteo-porosis is defined as a T-score ≤−2.5. Because of variance in the measurements obtained by the different commer-cial devices and at different sites, T- and Z-scores cannot be used as true screening tests, but they are good predic-tors of the risk of fracture. This information can be used to guide decisions about interventions including lifestyle changes and medical therapy to prevent or slow bone loss.

ACOG recommends bone mineral density testing for all post-menopausal women starting at age 65. Bone mineral density test-ing should also be performed in younger postmenopausal women who have at least one risk factor for osteoporosis (Box 2.4). Inaddition, postmenopausal women who experience a frac-ture should have bone mineral density testing to ascertain if they are osteoporotic; if so, treatment for osteoporosis is added to the therapy for the fracture. Certain diseases or medical conditions (e.g., Cushing disease, hyperpara-thyroidism, hypophosphatasia, inflammatory bowel disease, lymphoma, and leukemia) and certain drugs (e.g., phenobar-bital, phenytoin, corticosteroids, lithium, and tamoxifen) are associated with bone loss. Women with these conditions or taking these drugs may need to be tested more frequently.

Women should be counseled on the risks of osteo-porosis and related fractures and the following preventive measures:

·      Adequate calcium consumption (at least 1000 to 1500 mg/d) using dietary supplements if dietary sources are not adequate

·      Adequate vitamin D consumption (400 to 800 inter-national units daily) and exposure to the natural sources of this nutrient

·      Regular weight-bearing and muscle-strengthening exer-cises to reduce falls and prevent fractures

·      Smoking cessation

·      Moderation of alcohol intake

·      Fall prevention strategies

Diabetes Mellitus

Diabetes mellitus is a group of disorders that share hyper-glycemia as a common feature. Even when symptoms are not present, the disease can cause long-term complica-tions. Ideally, it should be detected and treated in its early stages. A screening fasting blood glucose test is recommendedfor women beginning at age 45 and every 3 years thereafter. Screening should begin at a younger age or more fre-quently in individuals with risk factors, which include being overweight (body mass index >=25), a family history of diabetes mellitus, habitual physical inactivity, having given birth to a newborn weighing more than 9 pounds, history of gestational diabetes, and hypertension.

Thyroid Disease

Thyroid disease is often asymptomatic and if untreatedcan lead to serious medical conditions. Thyroid-stimulatinghormone levels should be tested every 5 years starting at the age of 50.

Hypertension

It is estimated that approximately 30% of adults aged 20 and older have hypertension, which is defined as a systolic blood pressure of ≥140 mm Hg or a diastolic blood pres-sure of >=90 mm Hg. Hypertension is one of the most im-portant risk factors for heart disease and cerebrovascular accidents (CVAs), two of the three leading causes for mor-tality among women. Hypertension is also a leading cause of mortality. About a third of those with hypertension do not know they have it. Screening for hypertension is recom-mended for women and girls 13 years of age and older. Screen-ing may be repeated every 2 years in persons with normal blood pressure or annually with higher levels.

Lipid Disorders

Coronary heart disease (CHD) is a leading cause of death for both men and women in the United States and accounts for approximately 500,000 deaths each year. Abnormal cholesterol levels have been linked to atherosclerosis and cardiovascular and cerebrovascular disease. Clinical tri-als have shown that a 1% reduction in serum cholesterol levels results in a 2% reduction in CHD rates. Lipid lev-els are assessed with regard to low-density lipoprotein(LDL), high-density lipoprotein (HDL), and triglyc-erides. About one in five adult Americans has a high totalcholesterol level (>=240 mg/dL).

Current guidelines recommend that women without risk factors have a lipid profile assessment every 5 years, beginning at age 45 years. Earlier screening may be appropriate inwomen with risk factors. Risk factors for high cholesterol are a family history of familial hyperlipidemia, family his-tology of premature (age younger than 50 years for men and younger than 60 years for women) cardiovascular dis-ease, diabetes mellitus, and multiple coronary heart dis-ease risk factors (e.g., tobacco use, hypertension).

Obesity

Obesity is associated with increased risk for heart disease,type 2 diabetes, hypertension, some types of cancer (endo-metrial, colon, breast), sleep apnea, osteoarthritis, gall-bladder disease, and depression. Measurement of height andweight and the calculation of a BMI are recommended as part of the periodic assessment (Box 2.5). Obese people with a bodymass index (BMI) of 30 or more have up to twofold in-creased risk of death.