BACKGROUND: Cystinuria is a rare genetic disease characterized by impaired tubular transport of cystine. Clinical features of cystinuria mainly include nephrolithiasis and its complications, although cystinuric patients may present with other comorbidities. There are currently no data on bone features of patients with cystinuria. Our aim is to characterize bone mineral density (BMD) in cystinuria.
METHODS: Our study included adult cystinuric patients with estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m2 followed at 3 specialized outpatient clinics in Italy (Rome, Naples and Verona). Markers of bone turnover were analyzed in a centralized laboratory. Clinical, biochemical and dual-energy X-ray absorptiometry (DEXA) data were collected from September 2021 to December 2022. Linear regression models were used to evaluate statistically significant deviations from zero of Z-scores.
RESULTS: Twenty-seven patients were included in the study. Mean (SD) age was 37 (15) years, 41% were women. Mean estimated glomerular filtration rate was 99 mL/min/1.73 m2. Serum parameters associated with bone turnover (parathyroid hormone, FGF23, calcium and phosphate) were all in the normal range, with only 4 patients showing mild hypophosphatemia. Prevalence of low bone mineral density, defined as Z-score ≤  - 2 at any site, was 15%. Average Z-scores were negative across most sites.
CONCLUSIONS: Our study suggests that cystinuric patients have lower bone mineral density compared with individuals of the same sex and age, even when their kidney function is normal.

This study examined low bone mineral density (BMD) prevalence and associated factors among Chinese people living with HIV (PLWH), uncovering a persistent high BMD risk in older individuals, even after adjusting for age and body mass index (BMI). Notably, lopinavir/ritonavir (LPV/r) therapy was linked to reduced BMD, highlighting the imperative need for regular BMD monitoring and interventions in older PLWH.
OBJECTIVE: HIV infection and antiretroviral therapy (ART) have been shown to contribute to lower BMD, resulting in an increased susceptibility to osteopenia and osteoporosis. However, there is limited knowledge about the prevalence of reduced BMD and its associated factors among Chinese PLWH. In this cross-sectional study, we aimed to investigate the prevalence and factors associated with low BMD among PLWH in China.
METHODS: We retrospectively enrolled PLWH and non-HIV volunteers who underwent dual-energy X-ray absorptiometry (DXA) scans to measure bone density. Demographic information, laboratory test results, ART regimens, and treatment duration were collected. Univariate and multiple regression analyses were performed to identify factors influencing abnormal bone mass in PLWH.
RESULTS: A total of 829 individuals were included in this study, comprising the HIV group (n = 706) and the non-HIV group (n = 123). The prevalence of low BMD among all PLWH was found to be 13.88% (98 out of 706). However, among PLWH aged 50 years and above, the prevalence increased to 65.32% (81 out of 124). In contrast, control subjects in the same age group had a prevalence of 38.21% (47 out of 123). After adjusting for age and BMI, older PLWH still demonstrated a higher prevalence of low BMD compared to the non-HIV group (68.24% vs 34.94%, P < 0.001). Multivariate analysis revealed that older age was strongly associated with a higher risk of low BMD among PLWH, with an odds ratio (OR) of 6.28 for every 10-year increase in age in the ART-naïve population (95% confidence intervals [CIs], 3.12-12.65; P < 0.001) and OR of 4.83 in the ART-experienced population (3.20-7.29, P < 0.001). Within the ART-experienced group, current LPV/r treatment was associated with an increased risk of low BMD (OR = 3.55, 1.24-10.14, P < 0.05), along with lower BMI (OR = 0.84, 0.75-0.95, P < 0.05), and elevated alkaline phosphatase (OR = 1.02, 1.01-1.03, P < 0.01).
CONCLUSIONS: The prevalence of low BMD is higher among PLWH aged 50 years and above compared to non-HIV individuals. The use of LPV/r for ART is associated with reduced BMD. These findings emphasize the importance of regular monitoring of BMD in older PLWH and the need for appropriate interventions to mitigate the risks of osteopenia and osteoporosis in this population.

Raloxifene increases lumbar spine bone mineral density (BMD) and lowers vertebral fracture risk in patients with osteoporosis. However, few prospective clinical trials have studied its efficacy in postmenopausal women with osteopenia. This study investigated the efficacy of raloxifene in postmenopausal women with osteopenia. An investigator-initiated, randomized, open-label, prospective, single-center trial was conducted in 112 postmenopausal women with osteopenia. Osteopenia was defined based on the lowest BMD T-score in the lumbar spine, femoral neck, or total hip (-2.5 < lowest T-score < -1.0). Participants were randomly assigned to receive raloxifene 60 mg/day plus cholecalciferol 800 IU/day (RalD) or cholecalciferol 800 IU/day (VitD) for 48 wk. At baseline, mean age (63.1 ± 6.8 yr) did not differ between the two groups. However, in the RalD group, mean body mass index (BMI) and baseline T-score were lower, while 25-hydroxyvitamin D level was higher. At 48 wk, the RalD group showed a greater increase in lumbar spine BMD (RalD vs. VitD; 2.6% vs. -0.6%, P =.005) and attenuated the total hip BMD loss (-0.3% vs. -2.9%, P = .003). The effect of raloxifene on the lumbar spine remained significant after adjustment for age, BMI, baseline BMD T-score, and other covariates (adjusted β: +3.05 vs. VitD, P =.015). In subgroup analysis, the difference in lumbar spine BMD between the RalD and VitD groups was robust in those with severe osteopenia group (lowest T-score ≤ -2.0). Raloxifene plus cholecalciferol significantly improved lumbar spine BMD and attenuated total hip BMD loss compared with cholecalciferol alone, with a more robust effect in severe osteopenia. Clinical trial registration: The trial was registered with ClinicalTrials.gov (NCT05386784).

Nutritional secondary hyperparathyroidism (NSH) in dogs is a condition that develops in response to a vitamin D deficiency or an imbalanced calcium-to-phosphorus ratio in dog food. Puppies of large-breed dogs exclusively fed a non-supplemented, boneless raw meat diet are especially susceptible to developing NSH due to their elevated calcium requirement. Reports on NSH in companion animals have been sparse in the last decades due to dog owners having easy access to commercially balanced dog foods. However, with the rising popularity of meat-based raw feeding, this condition has re-emerged. In this case series, four large-breed puppies fed exclusively non-supplemented, boneless raw meat diets presented with complaints of acute onset of pain and paresis. Radiographs and/or computed tomography (CT) scans showed reduced radio density of the skeleton in all four puppies. Two of the dogs had pathological fractures, and these two puppies were euthanized. One was subjected to a post mortem examination, which revealed cortical bone resorption and hypertrophy of the parathyroid glands. The remaining two puppies rapidly improved after receiving pain medication and a commercial, balanced diet. This case series demonstrates a risk of young dogs developing severe neurological deficits when fed a non-supplemented, boneless raw meat diet.

BACKGROUND: Osteopenia reflects frailty and has been shown to be associated with outcomes in cancer patients. This study was undertaken to examine whether osteopenia is an independent prognostic factor in patients with esophageal cancer after resection.
METHODS: A total of 214 patients who underwent surgery for esophageal cancer were analyzed retrospectively. Bone mineral density (BMD) of the 11th thoracic vertebra was measured by computed tomography scan, and patients classified into osteopenia and normal BMD groups with BMD <160 Hounsfield units as the cutoff. Clinicopathological data and prognosis were analyzed.
RESULTS: The 5-year survival rate was 55.4% for the osteopenia group and 74.7% for the normal BMD group with a significantly worse prognosis in the osteopenia group (p = 0.0080). In multivariable analysis, osteopenia was a significant independent risk factor associated with overall survival (hazard ratio [HR] 1.90, 95% confidence interval [CI] 1.27-3.34, and p = 0.0151) along with R1/2 resection (HR 3.02, 95% CI 1.71-5.18, and p = 0.0002).
CONCLUSIONS: In patients with esophageal cancer undergoing resection, osteopenia may be a surrogate marker for frailty and an independent predictor of prognosis.

UNASSIGNED: The growing prevalence of vegetarianism determines the need for comprehensive study of the impact of these diets on health and particularly on bone metabolism. We hypothesized that significant dietary differences between vegans, lacto-ovo-vegetarians, and omnivores also cause significant differences in their nutrient status, which may affect bone health.
UNASSIGNED: The study assessed dual-energy X-ray absorptiometry parameters in lumbar spine and femoral neck, average nutrient intake, serum nutrient concentrations, serum PTH levels, and urinary pH among 46 vegans, 38 lacto-ovo-vegetarians, and 44 omnivores.
UNASSIGNED: There were no differences in bone mineral density (BMD) between the groups. However, the parathyroid hormone (PTH) levels were still higher in vegans compared to omnivores, despite the same prevalence of hyperparathyroidism in all groups. These findings may probably be explained by the fact that each group had its own \"strengths and weaknesses.\" Thus, vegans and, to a lesser extent, lacto-ovo-vegetarians consumed much more potassium, magnesium, copper, manganese, and vitamins B6, B9, and C. At the same time, the diet of omnivores contained more protein and vitamins D and B12. All the subjects consumed less vitamin D than recommended. More than half of vegans and omnivores had insufficiency or even deficiency of vitamin D in the blood. Low serum concentrations of manganese with its quite adequate intake are also noteworthy: its deficiency was observed in 57% of vegans, 79% of lacto-ovo-vegetarians, and 63% of omnivores.
UNASSIGNED: Currently, it is no longer possible to conclude that lacto-ovo-vegetarians have lower BMD than omnivores, as our research supported. Vegans in our study also did not demonstrate lower BMD values, only higher PTH blood concentrations, compared to omnivores, however, a large number of studies, including recent, show the opposite view. In this regard, further large-scale research is required. Vegans and lacto-ovo-vegetarians now have a variety of foods fortified with vitamins D and B12, as well as calcium. There is also a great diversity of ethically sourced dietary supplements. The found low concentrations of manganese require further investigation.

OBJECTIVE: Different ART (antiretroviral therapy) options may affect the risk of osteopenia/osteoporosis in people living with HIV (PLWH) having increased life expectancy. Current guidelines recommend bone mineral density (BMD) measurement only in patients at risk. In our study, we investigated the prevalence of osteopenia/osteoporosis and associated risk factors in naive patients not receiving ART.
METHODS: This study included 116 newly diagnosed, ART naive HIV-positive patients who were studied retrospectively. Vitamin D level, BMD measurement, CD4 and CD8 count, CD4/CD8 ratio, HIV RNA level, body mass index and other risk parameters of ART naive patients were included in our study.
RESULTS: Of 116 patients, 103 were male and 13 female. 47.4% (osteoporosis in 4.3%, osteopenia in 43.1%) of patients had osteopenia/osteoporosis. The patients with osteopenia/osteoporosis had older age (39.2±11.0 vs 32.0±8.6, p=0.0001), lower vitamin D levels (16.0±5.0 vs 24.4±6.3, p=0.0001), lower BMI (body mass index) (23.0±4.0 vs 24.6±4.6 p<0.05), lower CD4 and CD8 counts (405.1±885.0 vs 467.3± 695.1; 849.9570.4 vs 1012.0±629.4 respectively, p<0.05). 41.8% had CD4 count ≤200/μL (vs 18.0%, p=0.005). No statistically significant differences were observed in terms of gender distribution, smoking, alcohol and drug use, comorbidities and, additional drug use and HIV RNA >100 000 copies/ml. In multivariate analysis, age and vitamin D level were significant and independent (p<0.05) risk factors with osteoporosis/osteopenia.
CONCLUSIONS: Being over 40 years of age, CD4 count ≤200/μL, vitamin D level <20 ng/mL and low BMI are the most important risk factors for osteopenia/osteoporosis in ART naive patients. Among these parameters, age and vitamin D level were significant and independent risk factors. These factors may guide the determination of the need for dual-energy x-ray absorptiometry (DXA) testing in ART naive patients and drug choices in the treatment plan.

BACKGROUND: The associations between serum uric acid and osteoporosis or osteopenia remain controversial, and few studies have explored whether BMI acts as a mediators in the association between the SUA and OP/ osteopenia.
OBJECTIVE: To explore the relationship between serum uric acid and osteoporosis or osteopenia among US adults.
METHODS: A cross-sectional study was conducted to examine the association between serum uric acid and osteoporosis or osteopenia from four cycles of NHANES. Binary logistic regression models and restricted cubic spline models were used to evaluate the association between serum uric acid and osteoporosis or osteopenia, and interaction analysis was used to test the differences between subgroups. Mediation analysis was utilized to investigate whether BMI acts as a mediator in the association between SUA and OP/ osteopenia.
RESULTS: 12581 participants aged ≥ 18 years were included. A U-shape nonlinear relationship between SUA and osteoporosis or osteopenia in all people was found (P < 0.0001, P for nonlinear = 0.0287). There were significant interactions in age subgroups (P for interaction = 0.044), sex subgroups (P for interaction = 0.005), and BMI subgroups (P for interaction = 0.017). We further assessed the subgroups and found the optimal range of serum uric acid levels with a lower risk of osteoporosis or osteopenia was 357-535 µmol/L in males, 327-417 µmol/L in people aged ≥ 50 years, above 309 µmol/L in people aged < 50 years, 344-445 µmol/L in people with BMI ≥ 30, and above 308 µmol/L in people with BMI < 30. BMI fully mediated the association of SUA and OP/osteopenia, with a value of -0.0024(-0.0026--0.0021). These results were robust in sensitivity analyses.
CONCLUSIONS: A complicated relationship between SUA and bone health in different populations was observed. Maintaining SUA within a specific range may be beneficial to bone health. In addition, BMI may play an important role in the association between SUA and bone health, but considering the limitations of this study, further prospective research is required.

BACKGROUND: Osteopenia, caused by estrogen deficiency in postmenopausal women (PMW), lowers Bone Mineral Density (BMD) and increases bone fragility. It affects about half of older women\'s social and physical health. PMW experience pain and disability, impacting their health-related Quality of Life (QoL) and function. This study aimed to determine the effects of Kinect-based Virtual Reality Training (VRT) on physical performance and QoL in PMW with osteopenia.
METHODS: The study was a prospective, two-arm, parallel-design, randomized controlled trial. Fifty-two participants were recruited in the trial, with 26 randomly assigned to each group. The experimental group received Kinect-based VRT thrice a week for 24 weeks, each lasting 45 min. Both groups were directed to participate in a 30-min walk outside every day. Physical performance was measured by the Time Up and Go Test (TUG), Functional Reach Test (FRT), Five Times Sit to Stand Test (FTSST), Modified Sit and Reach Test (MSRT), Dynamic Hand Grip Strength (DHGS), Non-Dynamic Hand Grip Strength (NDHGS), BORG Score and Dyspnea Index. Escala de Calidad de vida Osteoporosis (ECOS-16) questionnaire measured QoL. Both physical performance and QoL measures were assessed at baseline, after 12 weeks, and after 24 weeks. Data were analyzed on SPSS 25.
RESULTS: The mean age of the PMW participants was 58.00 ± 5.52 years. In within-group comparison, all outcome variables (TUG, FRT, FTSST, MSRT, DHGS, NDHGS, BORG Score, Dyspnea, and ECOS-16) showed significant improvements (p < 0.001) from baseline at both the 12th and 24th weeks and between baseline and the 24th week in the experimental group. In the control group, all outcome variables except FRT (12th week to 24th week) showed statistically significant improvements (p < 0.001) from baseline at both the 12th and 24th weeks and between baseline and the 24th week. In between-group comparison, the experimental group demonstrated more significant improvements in most outcome variables at all points than the control group (p < 0.001), indicating the positive additional effects of Kinect-based VRT.
CONCLUSIONS: The study concludes that physical performance and QoL measures were improved in both the experimental and control groups. However, in the group comparison, these variables showed better results in the experimental group. Thus, Kinect-based VRT is an alternative and feasible intervention to improve physical performance and QoL in PMW with osteopenia. This novel approach may be widely applicable in upcoming studies, considering the increasing interest in virtual reality-based therapy for rehabilitation.

BACKGROUND: Osteopenia is a well-known risk factor for survival in patients with hepatocellular carcinoma; however, it is unclear whether osteopenia can apply to both genders and how osteopenia is associated with cancer progression. The aim of this study was to elucidate whether osteopenia predicts reduced survival in regression models in both genders and whether osteopenia is associated with the pathological factors associated with reduced survival.
METHODS: This study included 188 consecutive patients who underwent hepatectomy. Bone mineral density was assessed using computed tomography (CT) scan images taken within 3 months before surgery. Non-contrast CT scan images at the level of the 11th thoracic vertebra were used. The cutoff value of osteopenia was calculated using a threshold value of 160 Hounsfield units. Overall survival (OS) curves and recurrence-free survival (RFS) were constructed using the Kaplan-Meier method, as was a log-rank test for survival. The hazard ratio and 95% confidence interval for overall survival were calculated using Cox\'s proportional hazard model.
RESULTS: In the regression analysis, age predicted bone mineral density. The association in females was greater than that in males. The OS and RFS of osteopenia patients were shorter than those for non-osteopenia patients. According to univariate and multivariate analyses, osteopenia was an independent risk factor for OS and RFS. The sole pathological factor associated with osteopenia was microvascular portal vein invasion.
CONCLUSIONS: Models suggest that osteopenia may predict decreased OS and RFS in patients undergoing resection of hepatocellular carcinoma due to the mechanisms mediated via microvascular portal vein invasion.