Osteopenia Osteoporosis

Osteoporosis, the second most important threat to postmenopausal women, cannot be restricted to a have or have not condition. Bone health must rather be perceived as a continuum from normal bone to clinical fracture through osteopenia, osteoporosis, and subclinical fracture. Bone loss is the consequence of an increase in bone turnover, which is regulated by estrogens. Hypoestro-... 

Several investigators have diagnosed bone mineral loss, with features of osteopenia/osteoporosis on radiography, quantitative computed tomography, or absorptiometry, in patients receiving long-term G-CSF for severe congenital... 

In another child, who had osteoporotic vertebral collapse, extensive investigations showed reduced bone mineral content, reduced concentrations of osteocalcin, and features of osteoporosis on bone biopsy (SEDA-19, 344). The role of G-CSF was unclear, because bone mineral loss is a possible complication of the underlying disease. Indeed, improvement or stabilization during G-CSF treatment was noted in several patients (6). Furthermore, there was no apparent effect on height, head circumference, or weight in patients under 18 years of age (6). In another study, there was bone mineral loss with features of osteopenia/osteoporosis in 15 of 30 patients treated with G-CSF for a mean of 5.8 years for severe chronic neutropenia (65). However, six of nine patients investigated before G-CSF treatment had evidence of osteopenia/osteoporosis. 

Falls SSRIs and serotonin and noradrenalin reuptake inhibitors (SNRIs) have long been linked with an increased risk of osteopenia/osteoporosis potentiating falls and fractures, especially in tiie elderly. A biological mechanism for these risks associated with SSRIs has been idenhfied. Studies have demonstrated a reduction in osteoblast proliferation and activity following treatment with SSRIs, the magnitude of such effects being linked to affinity to the serotonin transporter. In addition, recent research examining serotonin receptor expression in human osteoblasts and osteoclasts has found that SSRIs differentially inhibit bone cells via apoptosis [10 ]. 

This association between SSRIs and an increased risk of osteopenia/osteoporosis and falls/fractures has received considerable recent attention with the publication of three meta-analytic and four large-scale population-based studies with case control or cohort designs. 

Patients with IBD, particularly those with CD, are also at risk for bone loss. This may be a function of malabsorption or an effect of repeated courses of corticosteroids. Patients with IBD should receive a baseline bone density measurement prior to receiving corticosteroids. Vitamin D and calcium supplementation should be used in all patients receiving long-term corticosteroids. Oral bisphosphonate therapy may also be considered in patients receiving prolonged courses of corticosteroids or in those with osteopenia or osteoporosis. 

Osteopenia (80%) and osteoporosis, usually affecting trabecular bone... 

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... 

The diagnosis of osteoporosis based on a low-trauma fracture or central hip and/or spine DXA using World Health Organization T-score thresholds. Normal bone mass is a T-score greater than -1, osteopenia is a T-score of-1 to -2.4, and osteoporosis is a T-score at or below -2.5. 

Once osteopenia or osteoporosis develops, the objective is to stabilize or improve bone mass and strength and prevent fractures. 

Kanis JA, Johnell O, Black DM, Downs RW Jr, Sarkar S, Fuerst T, et al. (2003) Effect of raloxifene on the risk of new vertebral fracture in postmenopausal women with osteopenia or osteoporosis a reanalysis of the Multiple Outcomes of Raloxifene Evaluation trial. Bone 33 293-300... 

Effect of Raloxifene on Invasive Breast Cancer Incidence by ER Status Postmenopausal Women with Osteopenia or Osteoporosis... 

Fig. 10.13. Effect of raloxifene on invasive breast cancer incidence by ER status in postmenopausal women with osteopenia or osteoporosis. Reproduced with permission from Delmas et al. (2005)...

Delmas P, Cauley JA, Burshell AL et al. (2005) Breast cancer risk reduction over 8 years in postmenopausal women with osteopenia or osteoporosis receiving raloxifene. Bone 36 S436-7... 

Women with osteoporosis, either densitometric or established, and some cases of osteopenia with increased fracture risk require pharmacological intervention. Any intervention for osteoporosis is expected to be long lasting. Thus it is difficult to expect that interventions in young postmenopausal women could be maintained for the remainder of one s fife. The susceptibility to side effects changes either with the process of aging or the repeated use of a given product. Sequential treatment schedules, adapted to the risk profile of each period, would probably be more suitable. 

Osteoporosis is defined as a generalized decrease in bone mass (osteopenia) that affects bone matrix and mineral content equally, giving rise to fractures of vertebral bodies with bone pain, kyphosis, and shortening of the torso. Fractures of the hip and the distal radius are also commoa The underlying process is a disequilibrium between bone formation by osteoblasts and bone resorption by osteoclasts. 

Spontaneous reports of osteoporosis, osteopenia, bone fractures, and delayed healing of bone fractures have been seen in the isotretinoin population. While causality to isotretinoin has not been established, an effect cannot be ruled out. Physicians should use caution when prescribing isotretinoin to patients with a genetic predisposition for age-related osteoporosis, a history of childhood osteoporosis conditions, osteomalacia, or other disorders of bone metabolism. This would include patients diagnosed with anorexia nervosa and those who are on chronic drug therapy that causes drug-induced osteoporosis/osteomalacia and/or affects vitamin D metabolism, such as systemic corticosteroids and any anticonvulsants. 

Osteoporosis is a metabolic bone disease characterized by low bone mass and micro-architectural deterioration of bone tissue. This will lead to bone fragility and consequent increase in bone fracture risk. Mean bone mineral density (BMD) is measured with dual X-ray absorptiometry (DEXA) and expressed in Tsc (Tscore). WHO standards are a Tsc that is 1 standard deviation (SD) below mean BMD is graded as normal bone, Tsc between 1 and 1.5 SD below mean BMD is graded as osteopenia and a Tsc of more than 2.5 SD below mean BMD is graded as osteoporosis. When the Tsc is below 1.5 SD mean BMD prevention of osteoporosis must be initiated. Primary osteoporosis is caused mainly by hormone deflciency in both women and men. Secondary osteoporosis may result from endocrine, metabolic, nutritional and autoimmune causes or from immobility because of trauma. Also the use of medicaments such as corticosteroids may be contributing. 

Human rPTH (1-34) has been produced by recombinant technologies, is now approved, and will soon be available for the treatment of osteoporosis. It is given subcutaneously, 25 Jig/day cyclically for 12 to 18 months, to increase bone density in individuals with a history of fractures, severe osteopenia, or osteoporosis. PTHrP (1-36) has also been synthesized and is in early clinical trials. 

A 48-year-old white man is noted to have osteopenia on a routine LS spine film while being evaluated for back pain. His bone density reveals osteoporosis of both his hip and LS spine. All of the choices are possible EXCEPT... 

Of 25 girls with idiopathic precocious puberty, 11 had not been treated and 14 had received leuprolide acetate monthly for at least 1 year they were compared with 19 healthy controls (55). There was no significant difference between the groups. There was no osteopenia or osteoporosis after therapy. 

Anticonvulsant treatment Fibrogenes imperfecta ossium Osteitis fibrosa cystica Osteomalacia Osteoporosis Osteopenia Osteosclerosis Renal osteodystrophy Rickets... 

Bone mineral density (BMD) is measured using dual energy X-ray absorptiometry (DEXA) usually at the neck of femur (on the hip). The World Health Organization defines a diagnosis of osteoporosis if the BMD is 2.5 standard deviations or more below the young adult female mean value. This difference is known as the T-score. Patients are considered to have osteopenia if the T-score is between -1 and -2.5. 

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