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Elderly men and women with HIV have lower bone mass than HIV negative controls. Decreased body mass index was the most important risk factor associated with decreased BMD. Bone demineralization was observed among HIV-infected subjects receiving either tenofovir or a protease inhibitor.

We describe the effects of the overexpression of noggin, a bone morphogenetic protein (BMP) inhibitor, on osteoblast differentiation and bone formation. Cells of the osteoblast and chondrocyte lineages, as well as bone marrow macrophages, showed intense β-gal histo- or cytostaining in adult noggin+/– mice that had a LacZ transgene inserted at the site of noggin deletion. Despite identical BMP levels, however, osteoblasts of 20-month-old C57BL/6J and 4-month-old senescence-accelerated mice (SAM-P6 mice) had noggin expression levels that were approximately fourfold higher than those of 4-month-old C57BL/6J and SAM-R1 (control) mice, respectively. U-33 preosteoblastic cells overexpressing the noggin gene showed defective maturation and, in parallel, a decreased expression of Runx-2, bone sialoprotein, osteocalcin, and RANK-L. Noggin did not inhibit the ligandless signaling and pro-differentiation action of the constitutively activated BMP receptor type 1A, ca-ALK-3. Transgenic mice overexpressing noggin in mature osteocalcin-positive osteoblasts showed dramatic decreases in bone mineral density and bone formation rates with histological evidence of decreased trabecular bone and CFU-osteoblast colonies at 4 and 8 months. Together, the results provide compelling evidence that noggin, expressed in mature osteoblasts, inhibits osteoblast differentiation and bone formation. Thus, the overproduction of noggin during biological aging may result in impaired osteoblast formation and function and hence, net bone loss

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We determined the relationship between patients' socioeconomic status and discussions with their primary care physicians about hormone replacement therapy (HRT) among women facing a decision about HRT within the prior year. The study included telephone interviews and medical record reviews. The setting was a general medicine practice of an urban teaching hospital in Boston, Mass. Women ages 50-65 visiting an academic teaching practice over a 3-month period were selected randomly. Of the 198 potential subjects, 118 (60%) agreed to participate in the survey. We examined discussions of HRT by women who had faced the decision to initiate HRT within the previous year. Women who were not on HRT or had been on therapy for less than 1 year were asked if they had discussed HRT with their physician in the past year. Socioeconomic factors and comorbidities were elicited during the survey and abstracted by chart review. The mean age of the 118 participants was 57; 36% were black, 54% were white, 10% were other race, 17% had less than a high school education, 14% had diabetes, 31% had had a hysterectomy, and 7% had a history of breast cancer. Of the 80 women who did not use HRT or had used it for less than 1 year, 49 (61%) reported a discussion of HRT. In bivariable analysis, patients of white race were more likely to report a discussion than black patients (72% versus 43%, odds ratio [OR] 3.6, 95% confidence interval [CI] 1.3-9.7). After adjustment for history of osteoporosis and age, white patients were more likely to report a discussion (adjusted OR 3.3, 95% CI 1.1-9.8). Further adjustment for the presence of 2 or more cardiac risk factors did not change the result. Neither level of education nor family income were significantly associated with HRT discussion. Compared with white women, the African-American women we studied were less likely to discuss HRT with their physicians. Further study is needed to determine whether the failure to discuss HRT is due to failure to initiate a discussion on the part of patients, physicians, or both.

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