Bone mineral density Osteoporosis

Alendronate, etidronate, and risedronate act primarily on the bone by inhibiting normal and abnormal bone resorption. This results in increased bone mineral density, reversing the progression of osteoporosis. 

It has been shown that in postmenopausal women habitually high intakes of dietary isoflavones are associated with higher bone mineral density (BMD) values at both the spine and hip region (Mei et al, 2001). It is conceivable that an isoflavone-rich diet may help to reverse the state of secondary hyperparathyroidism associated with estrogen withdrawal and hence lower the rate of bone turnover in postmenopausal women, thus reducing the risk of osteoporosis (Valtuena et al, 2003). Phytoestrogens could be used as natural SERMs (Brzezinski and Debi, 1999) and some studies (Setchell, 2001 and refs therein) support such an idea since the molecular targets of... 

One chronic adverse effect that is of concern is osteoporosis.32,33 Carbamazepine, phenytoin, phenobarbital, oxcarbazepine, and valproate have all been shown to decrease bone mineral density, even after only 6 months of treatment. Data on the relationship between other AEDs and osteoporosis are not currently available. Multiple studies have shown the risk of osteoporosis due to chronic AED use to be similar to the risk with chronic use of corticosteroids. Patients taking carbamazepine, phenytoin, phenobarbital, or valproate for longer than 6 months should take supplemental calcium and vitamin D. Additionally routine monitoring for osteoporosis should be performed every 2 years, and patients should be instructed on ways to protect themselves from fractures. 

The prolonged suppression of estrogen in pre-menopausal women with hyperprolactinemia leads to decreases in bone mineral density and significant risk for the development of osteoporosis. 

Osteoporosis Oral calcium supplementation (1000-5000 mg/day) Oral vitamin D Calcifediol (1000 lU/day) Calcitriol (0.5 mcg/day) Hormone-replacement therapy Calcitonin or oral bisphosphonates If daily intake less than 1000 mg elemental calcium Documented deficiency If kidney functioning If kidney not functioning Post-menopausal women without contraindications Documented loss in bone mineral density greater than 3% Data lacking for bisphosphonates in patients with Rl... 

All postmenopausal women with a personal history of osteoporotic fracture and/or low bone mineral density with risk factors for osteoporosis should receive treatment for osteoporosis. 

Many of the risk factors for osteoporosis and osteoporotic fractures are predictors of low bone mineral density, such as age and ethnicity (Table 53-1). The most important risk factors for fracture are low bone mineral density, personal history of adult fracture, age, and family history of osteoporotic fracture. Other important risk factors for osteoporosis and osteoporotic fractures include menopausal status, smoking status, and low body weight. As bone mineral density decreases, the risk of fracture increases. However, the threshold at which individual patients develop a fracture varies, and other factors may play a role in fracture susceptibility. One such factor that can influence the development of fracture is falling. 

Once the bone mineral density report is available, T-scores and Z-scores are useful tools in interpreting the data. The T-score is the number of standard deviations from the mean bone mineral density in healthy young white women. Osteoporosis is defined as a T-score at least -2.5 standard deviations below the mean (Table 53-3). Osteopenia, or low bone mass that eventually may lead to osteoporosis, is defined as a T-score between -2.5 and -1.0 standard deviations below the mean. The International Society for Clinical Densitometry recommends use of the WHO definition and T-scores for diagnosis of osteoporosis in postmenopausal women and men... 

Thiazide diuretics decrease urinary calcium excretion and may decrease bone turnover. However, their effects on bone mineral density and fracture rates have not been studied in controlled trials. Thiazide diuretics are not recommended solely for potential beneficial effects in osteoporosis. 

Although most fragility fractures in women occur after age 50, certain groups of premenopausal women are at high risk for osteoporosis. The NOF recommends measuring bone mineral density in premenopausal women with risk factors in addition to sex and race, in whom treatment would be considered.1 Premenopausal women at risk for osteoporosis should follow all nonpharmacologic recommendations for exercise and adequate calcium and vitamin D intake. Currently, no good data... 

Osteoporosis associated with RA follows a multifaceted pathogenesis, but the primary mechanism likely is mediated by osteoclast activity.12 The cytokines involved in the inflammatory process directly stimulate osteoclast and inhibit osteoblast activity. Additionally, arthritis medications can lead to increased bone loss. Bone mineral density should be evaluated at baseline and routinely using dual-energy x-ray absorptiometry.11,12... 

Osteoporosis Encourage patients to ingest adequate amounts of calcium and vitamin D, encourage smokers to discontinue tobacco use, and consider initiation of medications for osteoporosis (e.g., bisphosphonates, calcitonin, and parathyroid hormone) if the patient is taking glucocorticoids for an extended period of time or if the patient has evidence of low bone mineral density.15,41... 

Osteoporosis affects some 75 million people in Europe, Japan and the USA combined. The condition is characterized by progressive thinning of the bones, leading to bone fragility and increased risk of fracture. Treatment with Forsteo increases bone mineral density and generally entails daily s.c. injection for several months at dosage levels of 20 pg active/dose. 

DMPA has been associated with a reduction in bone mineral density (BMD), but it has not been associated with the development of osteoporosis or fractures. Recent evidence suggests that BMD loss may slow after 1 to 2 years of DMPA use. 

Bone mineral density should be measured in women older than 65 years and in women younger than 65 years with risk factors for osteoporosis. Repeat testing should be done as clinically indicated. 

Liu J, Zhu H, Huang Q, Zhang Z, Li H, Qin Y, Zhang Y, Wei D, Lu J, Liu H, Xen X, Liu Y, Ekangaki A, Zheng Y, Diez-Perez A, Harper K (2004) Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in Chinese postmenopausal women with osteoporosis a multi-center, randomized, placebo-controlled clinical trial. Chin Med J 117 1029-1035 (in English)... 

All women included in MORE met criteria for osteoporosis defined as a lumbar spine or femoral neck bone mineral density (BMD) T score equal to or less than 2.5 or as the presence of a radiographic vertebral fracture. These women are considered to be at lower risk for breast cancer than women with normal BMD since this parameter could partially reflect a woman s lifetime exposure to estrogens (Zhang et al. 1997). After the start of MORE, NHANES III criteria standardizing total hip BMD measurements became available allowing part of... 

The past 3 years have seen tremendous advances in both the design of Cat K inhibitors and in our understanding of the effect of Cat K inhibition on bone remodeling. The structural diversity of Cat K inhibitors has expanded considerably from simple peptidomimetics to non-peptidic derivatives and even non-covalent inhibitors. The potency, selectivity and pharmacokinetic properties of key compounds are very attractive and seem well-suited to further development. The disclosure of clinical validation of the effect of Cat K inhibition on bone mineral density, plus the provocative data suggesting a decoupling of bone resorption and bone formation provides a compelling framework for further development of Cat K inhibitors for the treatment of osteoporosis. 

Osteoporosis, a condition in which bone becomes porous and weak (potentially leading to fractures), is a far more prevalent disease than osteomalacia. While modest levels of serum 25-hydroxyvitamin D will prevent osteomalacia, these levels may not be sufficient to minimize the risk of osteoporosis. Clinical studies have demonstrated that bone mineral density is directly related to serum 25-hydroxyvitamin D levels up to 40 ng/ml. It has also been demonstrated that in elderly women given unusually high doses of calcium and vitamin D3 the risk of both hip and vertebral fractures is substantially reduced. Optimizing bone health in both young and old may require higher levels of vitamin D activity than are typically achieved at recommended doses. This story will play out over time. 

At menopause, the production of estrogens in females is markedly reduced. This leads to a number of unpleasant effects, including hot flashes and night sweats. More important for long-term health, the estrogen decrease is associated with an increased risk of cardiovascular disease and osteoporosis. The action of estrogens decreases plasma cholesterol and helps maintain good bone mineral density. 

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