Alterations in bone turnover in HIV-positive patients.
ABSTRACT Changes in mineral metabolism have recently been described in AIDS patients. To determine whether such changes affect bone turnover and bone mass, we studied 16 HIV-seropositive patients, classified according to Centers for Disease Control criteria, and 27 healthy controls. Biochemical markers of bone turnover and bone mineral density were analyzed. Serum concentrations of osteocalcin were abnormally low (0.5 +/- 1.3 ng/ml) in HIV-seropositive patients, in comparison with the control group (2.98 +/- 1.6 ng/ml) (p < 0.05). Urinary calcium/creatinine ratio was also decreased in HIV-positive patients (0.10 +/- 0.09 vs 0.14 +/- 0.09) (p < 0.05). In addition, bone mass was slightly lower in HIV-seropositive patients, although the difference was not statistically significant. The pathogenic mechanism of these alterations and their clinical relevance still remain unclear, and several factors may be implicated.
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ABSTRACT: Background: Osteoporosis commonly affects older men and women. Frequently, it is caused or exacerbated by a disease or treatment (termed secondary osteoporosis). The aim of this thesis is to explore aspects of the pathogenesis and treatment of three conditions that may cause or contribute to osteoporosis: human immunodeficiency virus (HIV) infection, primary hyperparathyroidism (PHPT), and vitamin D insufficiency. Each of these conditions is potentially linked to bone metabolism via associations with nutritional status, which in turn is a key regulator of bone mass and fracture risk. Methods: Eight studies were performed: 1. Cross-sectional comparison of bone mineral density (BMD) in HIV-infected men and age-matched controls. 2. Two-year randomised controlled trial of the effects of annual zoledronate on BMD in HIV-infected men. 3. Longitudinal comparison of the change in BMD over two years in HIV-infected men not receiving skeletal therapy and controls. 4. Meta-analysis of body weight in patients with PHPT. 5. Cross-sectional analysis of the relationship between parathyroid hormone and body weight in post-menopausal women. 6. Cross-sectional analysis of the determinants of 25-hydroxyvitamin D (25OHD) in post-menopausal women and middle-aged and older men. 7. Cross-sectional analysis of the effects of fat mass and seasonal variation on diagnosis of vitamin D sufficiency. 8. Cross-sectional analysis of the relationship between vitamin D binding protein and body weight in older men and women. Results: 1. HIV-infected men were 6.3 kg lighter than controls, and after adjustment for this weight difference, did not have lower BMD than controls. 2. Annual intravenous zoledronate caused substantial increases in BMD in HIV-infected men over two years. 3. HIV-infected men did not have accelerated bone loss over time compared to controls. 4. Patients with PHPT are on average 3.1-3.3 kg heavier than age-matched controls. 5. Fat mass is an important determinant of parathyroid hormone levels. 6. The major determinants of 25OHD levels in men and women are surrogate measures of ultraviolet-B exposure, and fat mass, but men have higher 25OHD levels throughout the year than women. 7. Thresholds for diagnosis of vitamin D sufficiency vary by season and amount of fat mass. 8. Vitamin D binding protein does not mediate the relationships between 25OHD and age, gender or weight. Conclusions: Uncomplicated HIV infection is not associated with low BMD at baseline or accelerated bone loss over time. There are important relationships between body weight and PHPT, and among fat mass, parathyroid hormone and 25OHD that have significance both for the pathogenesis of PHPT and vitamin D sufficiency, and for the clinical diagnosis and treatment of these conditions.
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ABSTRACT: Recently, a high incidence of osteopenia and osteoporosis has been observed in HIV-infected individuals. This problem seems to be more frequent in patients receiving potent antiretroviral therapy, although a specific contribution (if any) of the drugs used in combination regimens has yet to be established. There have also been several reports of other bone-related complications in HIV-infected individuals including avascular necrosis of the hip and compression fracture of the lumbar spine. People living with HIV have significant alterations in bone metabolism regardless of whether or not they are receiving potent antiretroviral therapy. The underlying mechanisms to account for these observations remain unknown, although studies are underway to examine the relationship between the bone abnormalities and other complications associated with HIV and antiretroviral therapy. HIV-infected patients with osteopenia or osteoporosis should be treated similarly to seronegative patients with appropriate use of nutritional supplements (Calcium and Vitamin D) and exercise. Hormone replacement and anti-resorptive therapies might be also indicated.
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ABSTRACT: The aim of this study was to identify and describe possible alterations of bone histomorphometry in patients with human immunodeficiency virus (HIV-1) infection and to assess the relation between these alterations and disease severity. Forty-four HIV-1-infected patients seen successively at our hospital were evaluated for the study. In an attempt to avoid confounding factors as far as possible, we excluded patients who fulfilled any of the following criteria: age less than 18 or greater than 40 years; recent history of extended bed rest; previous diagnosis of metabolic bone disease, renal insufficiency, or hepatic failure; clinical or echographic signs of liver cirrhosis; diabetes mellitus or previous diagnosis of other endocrine diseases; drug therapy that could act on bone metabolism; and/or moderate to severe nutritional alteration. Twenty-two patients (13 men, 9 women; age: 27.9 +/- 4.1 years, mean +/- standard deviation) were included in the study. Plasma and urine biochemistry and calcium-regulating hormones were determined. Bone mineral content was measured on vertebrae L2 to L4 and on the neck and intertrochanteric areas of the femur by dual-photon absorptiometry. A transiliac bone biopsy was performed after double-tetracycline labelling, with histomorphometric study of undecalcified bone. Serum osteocalcin was found to be lower in patients who, according to the Centers for Disease Control (CDC) classification, had greater disease severity, and showed a positive correlation with the number of CD4+ T lymphocytes. No alterations in bone densitometry were observed.(ABSTRACT TRUNCATED AT 250 WORDS)Bone 03/1995; 16(2):185-91. DOI:10.1016/8756-3282(94)00028-X · 4.46 Impact Factor