Calcaneal quantitative ultrasound and phalangeal radiographic absorptiometry alone or in combination in a triage approach for assessment of osteoporosis: a study of older women with a high prevalence of falls

Osteoporosis and bone metabolism in patients with Klinefelter syndrome

Low bone mass is common in men with Klinefelter syndrome (KS), with a prevalence of 6-15% of osteoporosis and of 25-48% of osteopenia. Reduced bone mass has been described since adolescence and it might be related to both reduced bone formation and higher bone resorption. Although reduced testosterone levels are clearly involved in the pathogenesis, this relation is not always evident. Importantly, fracture risk is increased independently from bone mineral density (BMD) and testosterone levels. Here we discuss the pathogenesis of osteoporosis in patients with KS, with a particular focus on the role of testosterone and testis function. In fact, other hormonal mechanisms, such as global Leydig cell dysfunction, causing reduced insulin-like factor 3 and 25-OH vitamin D levels, and high follicle-stimulating hormone and estradiol levels, might be involved. Furthermore, genetic aspects related to the supernumerary X chromosome might be involved, as well as androgen receptor expression and function. Notably, body composition, skeletal mass and strength, and age at diagnosis are other important aspects. Although dual-energy x-ray absorptiometry is recommended in the clinical workflow for patients with KS to measure BMD, recent evidence suggests that alterations in the microarchitecture of the bones and vertebral fractures might be present even in subjects with normal BMD. Therefore, analysis of trabecular bone score, high-resolution peripheral quantitative computed tomography and vertebral morphometry seem promising tools to better estimate the fracture risk of patients with KS. This review also summarizes the evidence on the best available treatments for osteoporosis in men with KS, with or without hypogonadism.

The Assessment of the Osteoporosis Self-Assessment Tool for Asians and Calcaneal Quantitative Ultrasound in Identifying Osteoporotic Fractures and Falls Among Chinese People

The lack of DXA has made the diagnosis and treatment of osteoporosis extremely difficult in the vast rural areas of China, which has the largest population with high risks of osteoporosis. The aims of this cross-sectional study were to evaluate the association between the osteoporosis self-assessment tool for Asians (OSTA) and calcaneus quantitative ultrasound (QUS) in populations residing in Shanghai, China, and their assessment in predicting osteoporotic fractures and falls. A population of 12,033 participants, including 1272 males (average age 68.3 ± 9.8 years, range 28-100 years) and 10,761 females (average 56.8 ± 11.4 years, range 23-99 years), was gathered. OSTA and calcaneus QUS (Sonost 2000, OsteoSys) values were measured. Spearman's correlation and Cohen's kappa were used to determine the association and agreement between the OSTA and QUS. Receiver operating characteristic (ROC) curves were adapted to assess the performance and optimal cutoff values for the OSTA and QUS in osteoporotic fracture and fall screening. In total, the prevalence of osteoporotic fractures (low-trauma fractures including fractures of the spine, hip, forearm, humerus and ribs) was 15.2% in women, and 17.7% reported a history of falls (falling from standing height more than once in the past year). The percentages of men with the same history were 8.4% and 11.7%, respectively. The association between the OSTA and QUS was found to be r_s = 0.393, κ = 0.137, p < 0.001. The OSTA (cutoff < -1) revealed an area under ROC curve (AUC) of 0.590 in identifying female individuals with moderate or high risk of osteoporosis defined by QUS (T-score < -1). The QUS T-score lower than -1.55 or -1.40 in postmenopausal women may lead to an increased risk of falls or osteoporotic fractures, respectively. The agreement between QUS and the OSTA seemed to be limited in determining individuals at risk of osteoporosis. Measuring bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) may still be necessary in the clinical diagnosis of osteoporosis. OSTA and QUS T-scores less than the respective cutoff values may indicate an increased risk of osteoporotic fractures and falls that individual should be further treated and screened by DXA.

Clinical Conformity Between Heel Ultrasound and Densitometry in Postmenopausal Women: A Systematic Review

OBJECTIVES

To assess the conformity between heel ultrasound and densitometry, and the clinical application of densitometry T-score "gold standard" in quantitative ultrasound as a method of osteoporosis diagnosis in postmenopausal women.

METHODS

The study is a systematic review of studies published in the last 17 years in PubMed, NLM Gateway, Medline, Embase, and Cochrane Library. Calcaneal quantitative ultrasound sensitivity and specificity were analyzed with regard to densitometry measurements in postmenopausal women. In addition, we summarized the values of ultrasound T-scores, for which their accuracy in osteoporosis diagnosis is the highest.

RESULTS

The inclusion criteria met 15 research studies conducted on postmenopausal women. In 11 of them, the authors concluded that clinical conformity between heel ultrasound and densitometry is good. The recommended quantitative ultrasound T-score for osteoporosis diagnosis ranged between -1 and -3.65.

CONCLUSIONS

Heel ultrasound should be considered to be as accurate as densitometry in diagnosing osteoporosis. Nevertheless, it needs to have separate T-score ranges determined, because those used in densitometry are not adequate.