Assessment of alveolar bone mineral density as a predictor of lumbar fracture probability.

INTRODUCTION: Osteoporosis and tooth loss have been linked with advancing age, but no clear relationship between these conditions has been proven. Several studies of bone mineral density measurements of the jaw and spine have shown similarities in their rate of age-related deterioration. Thus, measurements of jawbone density may predict lumbar vertebral bone density. Using jawbone density as a proxy marker would circumvent the need for lumbar bone measurements and facilitate prediction of osteoporotic spinal fracture susceptibility at dental clinics. We aimed to characterize the correlation between bone density in the jaw and spine and the incidence of osteoporotic spinal fractures. METHODS: We used computerized radiogrammetry to measure alveolar bone mineral density (al-BMD) and dual-energy X-ray absorptiometry to measure lumbar bone mineral density (L-BMD). L-BMD and al-BMD in 30 female patients (average age: 59 ± 5 years) were correlated with various patient attributes. Statistical analysis included area under the curve (AUC) and probability of asymptomatic significance (PAS) in a receiver operating characteristic curve. The predictive strength of L-BMD T-scores (L-BMD[T]) and al-BMD measurements for fracture occurrence was then compared using multivariate analysis with category weight scoring. RESULTS: L-BMD and al-BMD were significantly correlated with age, years since menopause, and alveolar bone thickness. Both were also negatively correlated with fracture incidence. Category weight scores were -0.275 for a L-BMD(T) <80%; +0.183 for a L-BMD(T) ≥ 80%; -0.860 for al-BMD <84.9 (brightness); and +0.860 for al-BMD ≥ 84.9. AUC and PAS analyses suggested that al-BMD had a higher association with fracture occurrence than L-BMD. CONCLUSIONS: Our results suggest the possible association between al-BMD and vertebral fracture risk. Assessment of alveolar bone density may be useful in patients receiving routine dental exams to monitor the clinical picture and the potential course of osteoporosis in patients who may be at a higher risk of developing osteoporosis.

Impact of obesity on IgA nephropathy: comparative ultrastructural study between obese and non-obese patients.

BACKGROUND: The pathological role of obesity in the progression of glomerular lesions has rarely been studied in primary glomerular diseases. The purpose of this study is to investigate the influence of non-diabetic obesity on clinicopathological findings in IgA nephropathy. METHODS: 74 patients with biopsy-proven IgA nephropathy were retrospectively divided into two groups according to the criteria for obesity in Japan: non-obese group (group N: n = 50) with BMI <25 kg/m(2), and obese group (group O: n = 24) with BMI > or =25 kg/m(2). Clinical and pathological data at the time of renal biopsy were analyzed. Moreover, the outcome of proteinuria in patients treated with angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin II receptor blockers (ARB) was evaluated in different groups after a 1-year follow-up. RESULTS: Urinary protein excretion was significantly greater in the obese group compared to normal-weight patients (p < 0.05). There was no significant difference in the prevalence of hypertension and hyperlipidemia. By light microscopy, the obese group showed significantly larger glomerular size (p < 0.0001). On the other hand, the severity of mesangial matrix expansion and crescent formation revealed no difference between the two groups. By electron microscopy, glomerular basement membrane (GBM) thickness was significantly increased in obese patients (p < 0.001). Among 61 patients who were followed up for 1 year in our institute, 15 patients were treated with ACE-I or ARB without steroids. ACE-I or ARB treatment without steroids tended to reduce proteinuria in the obese patients, but this change did not achieve statistical significance. CONCLUSIONS: In IgA nephropathy, obesity induces not only glomerular enlargement but also ultrastructural modification of GBM, which would contribute to increase proteinuria.

Clinicopathological influence of obesity in IgA nephropathy: comparative study of 74 patients.

The pathological role of obesity has rarely been studied in primary glomerular diseases. The purpose of this study is to examine the clinicopathological influence of obesity in IgA nephropathy (IgAN). 74 patients with IgA nephropathy in our institution from October 2000 to January 2004 were retrospectively divided into two groups according to body mass index (BMI): the non-obese group (group N) with BMI < 25 kg/m(2), and the obese group (group O) with BMI > or = 25 kg/m(2). There were 50 patients in group N and 24 patients in group O. Clinical analysis showed no significant difference between these two groups in blood pressure, serum cholesterol, creatinine clearances or grade of hematuria. However, urinary protein excretion and serum creatinine were significantly greater in group O than in group N. Although semiquantitative analysis of light-microscopical findings showed no significant differences in the severity of mesangial proliferation, matrix expansion, glomerulosclerosis or crescent formation, image analysis showed that total glomerular area and tuft area were significantly larger in group O. In addition, ultrastructural study revealed significantly higher glomerular basement membrane thickness in group O. 62 patients (46 patients, group N; 16 patients, group O) were followed in our institution for one year. Urinary protein was significantly decreased only in patients who received steroid in both groups. Although administration of ACE inhibitor or ARB tended to decrease urinary protein in group O, the change was not statistically significant. Our findings indicate that obesity may accelerate the increase of proteinuria in IgAN through ultrastructural modification of the glomerular basement membrane.

Effect of low-dose of recombinant human growth hormone on bone metabolism in elderly women with osteoporosis.

BACKGROUND: There has been increasing evidence that the growth hormone (GH)-IGF-I axis plays an important part in the maintenance of bone mass. However, controversy still exists as to the effect of GH treatment on bone mineral density (BMD) in elderly patients with osteoporosis. OBJECTIVE: To investigate the effect of low-dose GH treatment on markers of body composition and bone turnover, serum concentrations of IGF-I and IGF-binding proteins (IGFBPs), and BMD at the radius and lumbar spine in eight elderly Japanese women with osteoporosis. METHODS: Participants were treated with GH as a single daily subcutaneous injection (0.125 IU/kg per week; 0.00595 mg/kg per day) for 48 weeks. RESULTS: Markers of bone formation and bone resorption were both increased up to 24 weeks of GH treatment. The bone formation markers remained increased during GH treatment, whereas the bone resorption markers returned to baseline values after 24 weeks of GH treatment. GH treatment caused a rapid (within 2 weeks) and sustained increase in serum IGF-I concentration. As for IGFBPs, serum concentrations of IGFBPs-2, -3 and -4 did not change significantly during GH treatment. In contrast, GH treatment caused a gradual increase in serum IGFBP-5 concentration, with a significant increase seen 48 weeks after the start of GH treatment. Radial BMD seemed to be increased during the late period of GH treatment, although the change was not significant. Lumbar BMD did not change during GH treatment. GH treatment caused a significant increase in hand grip strength. None of the GH-treated participants had new fractures and side effects such as edema and joint pain. Radial BMD was significantly increased after discontinuation of GH treatment for another 48 weeks and a similar tendency was observed at the lumbar spine (7.1+/-2.3% above pretreatment values for the radius and 3.6+/-2.0% for the lumbar spine). CONCLUSIONS: Low-dose GH treatment attenuated the decrease in muscle strength and bone mass in elderly women without side effects, although changes in nutrition and exercise might affect BMD. The present findings provide useful information regarding the use of low-dose GH treatment in elderly women with osteoporosis.