Type 2 diabetes and bone

An investigation of composition, morphology, mechanical properties, and microdamage accumulation of human type 2 diabetic bone

This study investigates the biomechanics of type 2 diabetic bone fragility through a multiscale experimental strategy that considers structural, mechanical, and compositional components of ex vivo human trabecular and cortical bone. Human tissue samples were obtained from the femoral heads of patients undergoing total hip replacement. Mechanical testing was carried out on isolated trabecular cores using monotonic and cyclic compression loading and nanoindentation experiments, with bone microdamage analysed using micro-computed tomography (CT) imaging. Bone composition was evaluated using Raman spectroscopy, high-performance liquid chromatography, and fluorometric spectroscopy. It was found that human type 2 diabetic bone had altered mechanical, compositional, and morphological properties compared to non-type 2 diabetic bone. High-resolution micro-CT imaging showed that cores taken from the central trabecular region of the femoral head had higher bone mineral density (BMD), bone volume, trabecular thickness, and reduced trabecular separation. Type 2 diabetic bone also had enhanced macro-mechanical compressive properties under mechanical loading compared to non-diabetic controls, with significantly higher apparent modulus, yield stress, and pre-yield toughness evident, even when properties were normalised against the bone volume. Using nanoindentation, there were no significant differences in the tissue-level mechanical properties of cortical or trabecular bone in type 2 diabetic samples compared to controls. Through compositional analysis, higher levels of furosine were found in type 2 diabetic trabecular bone, and an increase in both furosine and carboxymethyl-lysine (an advanced glycation end-product) was found in cortical bone. Raman spectroscopy showed that type 2 diabetic bone had a higher mineral-to-matrix ratio, carbonate substitution, and reduced crystallinity compared to the controls. Together, this study shows that type 2 diabetes leads to distinct changes in both organic and mineral phases of the bone tissue matrix, but these changes did not coincide with any reduction in the micro- or macro-mechanical properties of the tissue under monotonic or cyclic loading.

Advanced glycation end products mediate biomineralization disorder in diabetic bone disease

Patients with diabetes often experience fragile fractures despite normal or higher bone mineral density (BMD), a phenomenon termed the diabetic bone paradox (DBP). The pathogenesis and therapeutics opinions for diabetic bone disease (DBD) are not fully explored. In this study, we utilize two preclinical diabetic models, the leptin receptor-deficient db/db mice (DB) mouse model and the streptozotocin-induced diabetes (STZ) mouse model. These models demonstrate higher BMD and lower mechanical strength, mirroring clinical observations in diabetic patients. Advanced glycation end products (AGEs) accumulate in diabetic bones, causing higher non-enzymatic crosslinking within collagen fibrils. This inhibits intrafibrillar mineralization and leads to disordered mineral deposition on collagen fibrils, ultimately reducing bone strength. Guanidines, inhibiting AGE formation, significantly improve the microstructure and biomechanical strength of diabetic bone and enhance bone fracture healing. Therefore, targeting AGEs may offer a strategy to regulate bone mineralization and microstructure, potentially preventing the onset of DBD.

Romosozumab rescues impaired bone mass and strength in a murine model of diabetic kidney disease

As international incidence of diabetes and diabetes-driven comorbidities such as chronic kidney disease (CKD) continue to climb, interventions are needed that address the high-risk skeletal fragility of what is a complex disease state. Romosozumab (Romo) is an FDA-approved sclerostin inhibitor that has been shown to increase bone mineral density and decrease fracture rates in osteoporotic patients with mild to severe CKD, but its effect on diabetes-weakened bone is unknown. We aimed to test Romo's performance in a model of combined diabetes and CKD. 6-week old male C57BL/6 mice were randomly divided into control (CON) and disease model (STZ-Ad) groups, using a previously established streptozotocin- and adenine-diet-induced model. After 16 weeks of disease induction, both CON and STZ-Ad groups were subdivided into two treatment groups and given weekly subcutaneous injections of 100 μL vehicle (phosphorus buffered saline, PBS) or 10 mg/kg Romo. Mice were euthanized after 4 weeks of treatment via cardiac exsanguination and cervical dislocation. Hindlimb bones and L4 vertebrae were cleaned of soft tissue, wrapped in PBS-soaked gauze and stored at -20C. Right tibiae, femora, and L4s were scanned via microcomputed tomography; tibiae were then tested to failure in 4-pt bending while L4s were compression tested. Romo treatment significantly increased cortical and trabecular bone mass in both STZ-Ad and CON animals. These morphological improvements created corresponding increases in cortical bending strength and trabecular compression strength, with STZ-Ad treated mice surpassing vehicle CON mice in all trabecular mechanics measures. These results suggest that Romo retains its efficacy at increasing bone mass and strength in diabetic kidney disease.

Characteristics of bone metabolism in the male patients with diabetic neuropathy

BACKGROUND

This study aimed to evaluate the characteristics of bone metabolism and fracture risk in the type 2 diabetes mellitus (T2DM) patients with distal symmetric polyneuropathy (DSPN).

METHODS

A total of 198 T2DM individuals were recruited from January 2017 to December 2020. Patients with DSPN were evaluated by strict clinical and sensory thresholds. Biochemical parameters and bone mineral density (BMD) were measured. The BMD, bone turnover markers, and probability of fracture were compared between two groups, and the factors related to BMD and probability of hip fracture in 10 years were further explored.

RESULTS

Compared with type 2 diabetes mellitus without distal symmetric polyneuropathy (T2DN-) patients, type 2 diabetes mellitus with distal symmetric polyneuropathy (T2DN+) patients had lower level of cross-linked C-telopeptide (CTX) (0.32 ± 0.19 vs 0.38 ± 0.21 ng/mL, p = 0.038) and higher level of bone-specific alkaline phosphatase (BALP) (15.28 ± 5.56 vs 12.58 ± 4.41 μg/mL, p = 0.003). T2DN+ patients had higher BMD of lumbar L1-L4 (1.05 ± 0.19 vs 0.95 ± 0.37, p = 0.027) and higher probability of hip fracture (0.98 ± 0.88 vs 0.68 ± 0.63, p = 0.009) as compared to T2DN- individuals. Univariate correlation analysis showed that BALP level (coefficient (coef) = -0.054, p = 0.038), CTX level (coef = -2.28, p = 0.001), and hip fracture risk (coef = -1.02, p < 0.001) were negatively related to the BMD of L1-L4. As for the risk of hip fracture evaluated by WHO Fracture Risk Assessment Tool (FRAX), age (coef = 0.035, p < 0.001), use of insulin (coef = 0.31, p =0.015), and levels of BALP (coef = 0.031, p = 0.017) and CTX (coef = 0.7, p = 0.047) were positively related to the risk of hip fracture. Multivariate regression analysis showed that CTX level (coef = -1.41, p = 0.043) was still negatively related to BMD at the lumbar spine.

CONCLUSION

This study indicates that T2DM patients with DSPN have special bone metabolism represented by higher BALP level and lower CTX level which may increase BMD at the lumbar spine.

Diabetes-related Screw Loosening: The Distinction of Surgical Sites and the Relationship among Diabetes, Implant Stabilization and Clinical Outcomes

OBJECTIVES

Diabetes mellitus (DM) is correlated with poor clinical outcomes in spinal surgery. However, the effect of it on screw stabilization has not been investigated. The aim of this study was to evaluate the screw loosening rate and postoperative outcomes in diabetic patients and to identify potential risk factors associated with loosening.

METHODS

This was a retrospective study. Two hundred and forty-three patients who received cervical or lumbar internal fixation between 2015 and 2019 were enrolled. Screw loosening was assessed on radiography, and clinical outcomes were evaluated by the improvement of visual analogue scale (VAS), Oswestry disability index (ODI) or Japanese Orthopaedic Association (JOA) scores. The relationship of DM, screw loosening and clinical outcomes were analyzed with chi-square tests and regression analyses.

RESULTS

One hundred and twenty-two patients (50.2%) with diabetes were included in this study. Diabetes led to the increase of the rate of screw loosening in the lumbar spine, while the loosening rate did not vary significantly in the cervical spine. The occurrence of screw loosening in the lumbar spine was more likely to be associated with clinical outcomes for motor performance including walking and sitting. However, no significant effect on JOA and VAS scores in the cervical spine of screw loosening was found. Moreover, the history of DM affected the outcomes of the patients who underwent spinal surgery.

CONCLUSION

DM had an adverse effect on screw stabilization. The impaired improvement of clinical outcomes in diabetics after spinal surgery was related to screw loosening. In addition to the direct effects on operative wounds and neural function, the impact on the screws due to DM was also worth noting.

Degree of Albuminuria is Associated With Increased Risk of Fragility Fractures Independent of Estimated GFR

Introduction

Fragility fractures are common in persons with chronic kidney disease (CKD); however, the association between fragility fractures and albuminuria is not well-studied. The primary objective of this study is to determine the association of albuminuria with incident risk of fragility fractures. The secondary objective is to examine the risk of fragility fracture by estimated glomerular filtration rate (eGFR) and Kidney Disease Improving Global Outcomes (KDIGO) risk categories.

Methods

Community dwelling adults residing in Alberta, Canada who had at least 1 creatinine and albuminuria measurement between April 1, 2008 and March 31, 2019 participated in the study (N = 2.72 million). Incident fragility fractures were identified using Canadian Chronic Disease Surveillance Systems Osteoporosis Working Group algorithms. Albuminuria was categorized as none/mild (albumin-to-creatinine ratio [ACR] <30 mg/g, protein-to-creatinine ratio [PCR] <150 mg/g, trace/negative dipstick); moderate (ACR 30-300 mg/g, PCR 150-500 mg/g, 1+ dipstick) or severe (ACR >300 mg/g, PCR >500 mg/g, ≥2+ dipstick). Multivariable analysis controlled for 42 variables.

Results

Patients with severe albuminuria had an increased risk of hip fracture (odds ratio [OR] = 1.37; 95% confidence interval [CI] 1.28, 1.47]), vertebral fracture (OR = 1.31; 95% CI 1.21, 1.41) and any-type fracture (OR = 1.22; 95% CI 1.17, 1.28) compared with patients with none/mild albuminuria. Patients in the most severe KDIGO risk category had an increased risk of hip fracture (OR = 1.22; 95% CI 1.16, 1.29), vertebral fracture (OR = 1.18; 95% CI 1.09, 1.26) and any type of fracture (OR = 1.25; 95% CI 1.21, 1.30).

Conclusion

This study demonstrates the important role of albuminuria as a risk factor for fragility fractures in CKD and may help inform risk stratification and prevention strategies in this high-risk population category.

Causal relationship between type 2 diabetes mellitus and bone mineral density: a Mendelian randomization study in an East Asian population

It remains unclear whether the relationship between type 2 diabetes mellitus (T2DM) and bone mineral density (BMD) reflects causality in East Asian populations. Herein, a Mendelian randomization study conducted in East Asian population enhances the current clinical cognition that T2DM is not associated with reduction in BMD.

PURPOSE

A Mendelian randomization (MR) approach was utilized to investigate the relationship between type 2 diabetes mellitus (T2DM) and bone mineral density (BMD) in East Asian populations.

METHODS

Genome-wide association study summary data from BioBank Japan were used to identify genetic variants strongly related to T2DM risk (36,614 cases and 155,150 controls) and osteoporosis (7788 cases and 204,665 controls). Heel BMD GWAS data of 1260 East Asian people from ieu open gwas project was considered as a second outcome. Inverse variance-weighted (IVW) analysis was mainly applied; MR-Egger and the weighted median were also used to obtain robust estimates. A series of sensitivity analyses including Cochran's Q test, MR-Egger regression, and leave-one-out analysis were used to detect pleiotropy or heterogeneity.

RESULTS

In the main analysis, IVW estimates indicated that T2DM significantly associated with the risk of osteoporosis (odds ratio = 0.92, 95% CI: 0.86-0.99, p = 0.016) and with higher BMD (OR: 1.25, 95% CI: 1.06-1.46, p = 6.49 × 10-3). Results of comprehensive sensitivity analysis were consistent with the main causality estimate. Horizontal pleiotropy and heterogeneity were absent in our MR study.

CONCLUSIONS

T2DM is not associated with reduction in BMD in terms of genetic polymorphism in East Asian populations.

Anti-inflammatory and pro-regenerative effects of a monoterpene glycoside on experimental periodontitis in a rat model of diabetes

OBJECTIVE

Paeoniflorin (Pae) is a monoterpene glycoside with immune-regulatory effects. Several studies have already demonstrated the impact of Pae on periodontitis, but its effect on diabetic periodontitis is unclear. In this study, our aim was to test the hypothesis that Pae had a strong anti-inflammatory effect that prevented bone loss in diabetic periodontitis.

METHODS

Thirty male Wistar albino rats were randomly divided into control (healthy, n = 10), periodontitis (PD) + diabetes (DM; n = 10), and PD + DM + Pae (n = 10) groups. Ligature-induced periodontitis was created by placing 4-0 silk ligatures around the lower first molars on both sides of the mandibulae. Experimental DM was created via an injection of 50 mg/kg and streptozotocin (STZ). Hyperglycemia was confirmed by the blood glucose levels of rats (>300 mg/dL). The bone mineral density (BMD), trabecular number, trabecular thickness, and bone loss were measured by micro-CT. The expression levels of IL-1β, IL-6, and TNF-α were measured in tissue homogenates by ELISA.

RESULTS

The PD + DM + Pae group had significantly less alveolar crest resorption when compared to the PD + DM group. There was also a significant difference between the PD + DM + Pae group compared to PD + DM group in trabecular thickness, BMD, and the number of trabeculae. Pae application led to a statistically significant decrease in IL-1β, IL-6, and TNF-α levels in diabetic periodontitis.

CONCLUSION

Systemic application of Pae suppressed inflammation caused by PD and DM, leading to reduced bone loss and enhanced bone quality.

Association of hyponatremia with bone mineral density and fractures: a narrative review

Recent studies suggest a possible association of hyponatremia with osteoporosis, falls and bone fractures. The objectives of this narrative review were to further explore this association and the related pathophysiological mechanisms and to suggest a practical approach to patients with osteoporosis or chronic hyponatremia in clinical practice. We conducted an extensive PubMed search until October 2022 with the combination of the following keywords: 'hyponatremia' or 'sodium' or 'SIADH' and 'fractures' or 'bone' or 'osteoporosis', as MeSH Terms. Review of numerous observational studies confirms a significant independent association of, even mild, hyponatremia with two- to three-fold increase in the occurrence of bone fractures. Hyponatremia is a risk factor for osteoporosis with a predilection to affect the hip, while the magnitude of association depends on the severity and chronicity of hyponatremia. Chronic hyponatremia also increases the risk for falls by inducing gait instability and neurocognitive deficits. Besides the detrimental impact of hyponatremia on bone mineral density and risk of falls, it also induces changes in bone quality. Emerging evidence suggests that acute hyponatremia shifts bone turnover dynamics towards less bone formation, while hyponatremia correction increases bone formation. The key unanswered question whether treatment of hyponatremia could improve osteoporosis and lower fracture risk highlights the need for prospective studies, evaluating the impact of sodium normalization on bone metabolism and occurrence of fractures. Recommendations for clinical approach should include measurement of serum sodium in all individuals with fracture or osteoporosis. Also, hyponatremia, as an independent risk factor for fracture, should be taken into consideration when estimating the likelihood for future fragility fracture and in clinical decision-making about pharmacological therapy of osteoporosis. Until it is proven that normalization of sodium can lower fracture occurrence, correcting hyponatremia cannot be universally recommended on this basis, but should be decided on a case-by-case basis.

Protective effects of curcumin against osteoporosis and its molecular mechanisms: a recent review in preclinical trials

Osteoporosis (OP) is one of the most common metabolic skeletal disorders and is commonly seen in the elderly population and postmenopausal women. It is mainly associated with progressive loss of bone mineral density, persistent deterioration of bone microarchitecture, and increased fracture risk. To date, drug therapy is the primary method used to prevent and treat osteoporosis. However, long-term drug therapy inevitably leads to drug resistance and specific side effects. Therefore, researchers are constantly searching for new monomer compounds from natural plants. As a candidate for the treatment of osteoporosis, curcumin (CUR) is a natural phenolic compound with various pharmacological and biological activities, including antioxidant, anti-apoptotic, and anti-inflammatory. This compound has gained research attention for maintaining bone health in various osteoporosis models. We reviewed preclinical and clinical studies of curcumin in preventing and alleviating osteoporosis. These results suggest that if subjected to rigorous pharmacological and clinical trials, naturally-derived curcumin could be used as a complementary and alternative medicine for the treatment of osteoporosis by targeting osteoporosis-related mechanistic pathways. This review summarizes the mechanisms of action and potential therapeutic applications of curcumin in the prevention and mitigation of osteoporosis and provides reference for further research and development of curcumin.

Suppression of TLR4 prevents diabetic bone loss by regulating FTO-mediated m6A modification

Toll-like receptor-4 (TLR4) has been implicated in the development and progression of diabetic osteoporosis. However, the mechanisms underlying TLR4-regulated bone metabolism in diabetes are yet to be fully understood. Epigenetic modifications have been indicated as a possible mechanism leading to increased risk of osteoporosis and bone fracture. As N6-methyladenosine (m6A) is the most common epigenetic modification in eukaryotic mRNAs, we hypothesized that TLR4 regulates m6A modification in bone tissues of diabetic rats, thereby potentially explaining the pathogenesis of diabetic bone loss. m6A sequencing (m6A-seq) was performed in samples of the femur of TLR4-wild type (TLR4WT) and TLR4-knockout (TLR4KO) diabetic rats to identify genes with differential m6A modifications that may be associated with the bone loss phenotype. We found that in TLR4KO rats, the rapid weight loss of diabetic rats was prevented, and bone mineral density (BMD) was significantly increased. m6A-seq and Gene Ontology enrichment analysis revealed that m6A-modified genes in the femur of TLR4KO diabetic rats were associated with regulation of biological processes such as osteoclast differentiation. qRT-PCR analysis on the expression levels of the m6A-modified methyltransferases and demethylases demonstrated that only the m6A demethylase fat mass and obesity-associated protein（FTO）was decreased. Using an osteoclast cell model, we confirmed that TLR4-mediated osteoclast differentiation was induced by glycolipid toxicity via inhibition of FTO expression. Taken together, these results suggest that inhibition of TLR4 may prevent diabetic bone loss via regulation of FTO-mediated m6A modification.

Exploring the Paradox of Bone Mineral Density in Type 2 Diabetes: A Comparative Study Using Opportunistic Chest CT Texture Analysis and DXA

BACKGROUND

This study aimed to validate the application of CT texture analysis in estimating Bone Mineral Density (BMD) in patients with Type 2 Diabetes (T2D) and comparing it with the results of dual-energy X-ray absorptiometry (DXA) in a normative cohort.

METHODS

We analyzed a total of 510 cases (145 T2D patients and 365 normal patients) from a single institution. DXA-derived BMD and CT texture analysis-estimated BMD were compared for each participant. Additionally, we investigated the correlation among 45 different texture features within each group.

RESULTS

The correlation between CT texture analysis-estimated BMD and DXA-derived BMD in T2D patients was consistently high (0.94 or above), whether measured at L1 BMD, L1 BMC, total hip BMD, or total hip BMC. In contrast, the normative cohort showed a modest correlation, ranging from 0.66 to 0.75. Among the 45 texture features, significant differences were found in the Contrast V 64 and Contrast V 128 features in the normal group.

CONCLUSION

In essence, our study emphasizes that the clinical assessment of bone health, particularly in T2D patients, should not merely rely on traditional measures, such as DXA BMD. Rather, it may be beneficial to incorporate other diagnostic tools, such as CT texture analysis, to better comprehend the complex interplay between various factors impacting bone health.

Hip structural analysis, trabecular bone score, and bone mineral density in post-menopausal women with type-2 diabetes mellitus: a multi-center cross-sectional study in the south of Iran

This study aimed to evaluate bone mineral density (BMD), trabecular microarchitecture, and proximal hip geometry in diabetic postmenopausal women, where BMD alone cannot reflect bone strength adequately. We found significantly lower trabecular bone score and BMD at the distal radius and total forearm in diabetic subjects compared to controls.

PURPOSE

The limitations resulting from the exclusive assessment of bone mineral density (BMD) in people with diabetes can lead to underestimation of microarchitectural and geometric changes, both of which play an essential role in the fracture risk. Therefore, we aimed to evaluate BMD, trabecular bone score (TBS), and hip structural analysis (HSA) in diabetic type-2 post-menopausal women and compare them with healthy postmenopausal subjects.

METHODS

BMD was assessed at the lumbar spine, femoral sites, distal radius, and total forearm using dual-energy X-ray absorptiometry (DXA); TBS was measured based on DXA images using the software at the same region of interest as the BMD measurements; geometric assessment at the proximal femur was performed by the HSA program.

RESULTS

A total of 348 ambulatory type-2 diabetic postmenopausal women and 539 healthy postmenopausal women were enrolled. TBS and BMD at the distal radius and total forearm were significantly (P value < 0.05) lower in cases compared to controls after age and body mass index (BMI) adjustment. In addition, degraded bone microarchitecture was significantly (P value < 0.05) more prevalent in diabetic subjects than in non-diabetic controls after adjusting for age and BMI. A number of geometric indices of the proximal hip were significantly lower in the controls than in those with diabetes (P-value < 0.05).

CONCLUSION

This study may highlight the utility of the TBS and BMD at the distal radius and total forearm in subjects with type-2 diabetes mellitus, where the BMD at central sites may not adequately predict fracture risk.

Bone structure and composition in a hyperglycemic, obese, and leptin receptor-deficient rat: Microscale characterization of femur and calvarium

Metabolic abnormalities, such as diabetes mellitus and obesity, can impact bone quantity and/or bone quality. In this work, we characterize bone material properties, in terms of structure and composition, in a novel rat model with congenic leptin receptor (LepR) deficiency, severe obesity, and hyperglycemia (type 2 diabetes-like condition). Femurs and calvaria (parietal region) from 20-week-old male rats are examined to probe bones formed both by endochondral and intramembranous ossification. Compared to the healthy controls, the LepR-deficient animals display significant alterations in femur microarchitecture and in calvarium morphology when analyzed by micro-computed X-ray tomography (micro-CT). In particular, shorter femurs with reduced bone volume, combined with thinner parietal bones and shorter sagittal suture, point towards a delay in the skeletal development of the LepR-deficient rodents. On the other hand, LepR-deficient animals and healthy controls display analogous bone matrix composition, which is assessed in terms of tissue mineral density by micro-CT, degree of mineralization by quantitative backscattered electron imaging, and various metrics extrapolated from Raman hyperspectral images. Some specific microstructural features, i.e., mineralized cartilage islands in the femurs and hyper-mineralized areas in the parietal bones, also show comparable distribution and characteristics in both groups. Overall, the altered bone microarchitecture in the LepR-deficient animals indicates compromised bone quality, despite the normal bone matrix composition. The delayed development is also consistent with observations in humans with congenic Lep/LepR deficiency, making this animal model a suitable candidate for translational research.

Increased fracture risk in Parkinson's disease - An exploration of mechanisms and consequences for fracture prediction with FRAX

The relative contributions of factors such as muscle strength, falls risk and low bone mineral density (BMD) to increased fracture risk in Parkinson's Disease (PD) were examined in an analysis of 5212 community-dwelling women age 75 years or more recruited to a randomised, double-blind, placebo-controlled study of the oral bisphosphonate, clodronate. Similar number of PD and non-PD subjects received treatment. Each participant had measurements of hip and forearm BMD, muscle strength (hand grip strength and maximum isometric quadriceps strength), ability in the sit-to-stand test, and postural stability. Incident radiographic and/or surgically verified fractures, and deaths, were recorded over an average follow-up of 3.8 years. A diagnosis of PD was made if it was self-reported and appropriate medication was recorded at the study entry. 47 of the women (0.9 %) had a diagnosis of PD at baseline. They were of similar age to those without PD, but reported higher disability scores and lower quality of life. While BMD at the forearm and hip regions was lower in PD, this only reached statistical significance at the femoral neck (0.61 ± 0.12 vs 0.65 ± 0.12 g/cm², p = 0.037). Right hand grip strength was non-significantly lower in PD, but maximum right quadriceps strength was much reduced (96.9 ± 49.3 vs 126.3 ± 59.2 N, p = 0.003). Eleven (23.4 %) of the women with PD sustained 12 fractures, while 609 women (11.8 %) without PD sustained 742 osteoporotic fractures. The risk of osteoporotic fracture associated with PD was 2.24-fold higher in women with PD (Cox-regression HR 2.24, 95 % CI 1.23-4.06) and this remained high when adjusted for death as a competing risk (2.17, 95 % CI 1.17-4.01, p = 0.013). Following adjustment for femoral neck BMD, PD remained a significant predictor of fracture (HR 2.04, 1.12-3.70, p = 0.020). Entering PD as a risk variable using the rheumatoid arthritis input as a surrogate resulted in a reduction in PD as a FRAX-independent risk factor, particularly when BMD was included in FRAX (1.65, 95 % CI), but the relationship between PD and fracture risk appears to remain of clinical significance. The study suggests that PD may be an independent input in future iterations of FRAX, possibly due to non-skeletal components of risk such as reduced lower limb muscle strength. Introducing measures of muscle strength and performance in FRAX could also be considered.

Glycemic Control and Bone in Diabetes

PURPOSE OF REVIEW

This review summarizes recent developments on the effects of glycemic control and diabetes on bone health. We discuss the foundational cellular mechanisms through which diabetes and impaired glucose control impact bone biology, and how these processes contribute to bone fragility in diabetes.

RECENT FINDINGS

Glucose is important for osteoblast differentiation and energy consumption of mature osteoblasts. The role of insulin is less clear, but insulin receptor deletion in mouse osteoblasts reduces bone formation. Epidemiologically, type 1 (T1D) and type 2 diabetes (T2D) associate with increased fracture risk, which is greater among people with T1D. Accumulation of cortical bone micro-pores, micro-vascular complications, and AGEs likely contribute to diabetes-related bone fragility. The effects of youth-onset T2D on peak bone mass attainment and subsequent skeletal fragility are of particular concern. Further research is needed to understand the effects of hyperglycemia on skeletal health through the lifecycle, including the related factors of inflammation and microvascular damage.

Diabetes and bone

Globally, one in 11 adults has diabetes mellitus of which 90% have type 2 diabetes. The numbers for osteoporosis are no less staggering: 1 in 3 women has a fracture after menopause, and the same is true for 1 in 5 men after the age of 50 years. Aging is associated with several physiological changes that cause insulin resistance and impaired insulin secretion, which in turn lead to hyperglycemia. The negative balance between bone resorption and formation is a natural process that appears after the fourth decade of life and lasts for the following decades, eroding the bone structure and increasing the risk of fractures. Not incidentally, it has been acknowledged that diabetes mellitus, regardless of whether type 1 or 2, is associated with an increased risk of fracture. The nuances that differentiate bone damage in the two main forms of diabetes are part of the intrinsic heterogeneity of diabetes, which is enhanced when associated with a condition as complex as osteoporosis. This narrative review addresses the main parameters related to the increased risk of fractures in individuals with diabetes, and the mutual factors affecting the treatment of diabetes mellitus and osteoporosis.

Update of the fracture risk prediction tool FRAX: a systematic review of potential cohorts and analysis plan

We describe the collection of cohorts together with the analysis plan for an update of the fracture risk prediction tool FRAX with respect to current and novel risk factors. The resource comprises 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures.

INTRODUCTION

The availability of the fracture risk assessment tool FRAX® has substantially enhanced the targeting of treatment to those at high risk of fracture with FRAX now incorporated into more than 100 clinical osteoporosis guidelines worldwide. The aim of this study is to determine whether the current algorithms can be further optimised with respect to current and novel risk factors.

METHODS

A computerised literature search was performed in PubMed from inception until May 17, 2019, to identify eligible cohorts for updating the FRAX coefficients. Additionally, we searched the abstracts of conference proceedings of the American Society for Bone and Mineral Research, European Calcified Tissue Society and World Congress of Osteoporosis. Prospective cohort studies with data on baseline clinical risk factors and incident fractures were eligible.

RESULTS

Of the 836 records retrieved, 53 were selected for full-text assessment after screening on title and abstract. Twelve cohorts were deemed eligible and of these, 4 novel cohorts were identified. These cohorts, together with 60 previously identified cohorts, will provide the resource for constructing an updated version of FRAX comprising 2,138,428 participants with a follow-up of approximately 20 million person-years and 116,117 documented incident major osteoporotic fractures. For each known and candidate risk factor, multivariate hazard functions for hip fracture, major osteoporotic fracture and death will be tested using extended Poisson regression. Sex- and/or ethnicity-specific differences in the weights of the risk factors will be investigated. After meta-analyses of the cohort-specific beta coefficients for each risk factor, models comprising 10-year probability of hip and major osteoporotic fracture, with or without femoral neck bone mineral density, will be computed.

CONCLUSIONS

These assembled cohorts and described models will provide the framework for an updated FRAX tool enabling enhanced assessment of fracture risk (PROSPERO (CRD42021227266)).

Effects of Resveratrol, Curcumin and Quercetin Supplementation on Bone Metabolism—A Systematic Review

Phenolic compounds are natural phytochemicals that have recently reported numerous health benefits. Resveratrol, curcumin, and quercetin have recently received the most attention among these molecules due to their documented antioxidant effects. The review aims to investigate the effects of these molecules on bone metabolism and their role in several diseases such as osteopenia and osteoporosis, bone tumours, and periodontitis. The PubMed/Medline, Web of Science, Google Scholar, Scopus, Cochrane Library, and Embase electronic databases were searched for papers in line with the study topic. According to an English language restriction, the screening period was from January 2012 to 3 July 2022, with the following Boolean keywords: (“resveratrol” AND “bone”); (“curcumin” AND “bone”); (“quercetin” AND “bone”). A total of 36 papers were identified as relevant to the purpose of our investigation. The studies reported the positive effects of the investigated phenolic compounds on bone metabolism and their potential application as adjuvant treatments for osteoporosis, bone tumours, and periodontitis. Furthermore, their use on the titanium surfaces of orthopaedic prostheses could represent a possible application to improve the osteogenic processes and osseointegration. According to the study findings, resveratrol, curcumin, and quercetin are reported to have a wide variety of beneficial effects as supplement therapies. The investigated phenolic compounds seem to positively mediate bone metabolism and osteoclast-related pathologies.

Associations of visceral adipose tissue with bone mineral density and fracture: observational and Mendelian randomization studies

BACKGROUND

The associations between visceral adipose tissue (VAT) and bone mineral density (BMD) or fracture have been controversial and the causality of the associations remains to be assessed. This study aimed to explore the associations of VAT^ (predicted value of VAT mass) with BMD and fracture risk in men and women, and to examine their potential causation by two-sample Mendelian randomization (MR) analyses.

METHODS

UK Biobank is a large, population-based prospective cohort study that recruited more than 500,000 participants aged 40-69 in the United Kingdom from 2006 to 2010. In this study, we used a validated and reliable prediction model to estimate the VAT amount of the participants. On this basis, linear and nonlinear multivariable statistical models were used to explore the association of VAT^ with BMD and fracture risk in different groups of sex and BMI. In observational analyses, the multivariable linear regression model and Cox proportional-hazards model were used to assess VAT^ association with BMD and fracture risk, respectively. Inverse variance weighting was used as the main result of MR analysis.

RESULTS

In 190,836 men, an inverted U-shaped association was observed between VAT^ and heel BMD (P for nonlinearity < 0.001), with a turning point of VAT^ = 1.25 kg. Per kg increase in VAT^ was associated with a 0.13 standard deviation (SD) increase in heel BMD (P = 1.5 × 10^-16) among men with lower amounts of VAT^, and associated with a 0.05 SD decrease in heel BMD (P = 1.3 × 10^-15) among men with higher amounts of VAT^. In 193,592 women, per kg increase in VAT^ was monotonically associated with a 0.16 SD increase in heel BMD (P = 1.2 × 10^-136, P for VAT^-sex interaction = 8.4 × 10^-51). During a median follow-up of 8.2 years, VAT^ was associated with lower risks of hip fractures in the overall men and women (P for VAT^-sex interaction = 1.9 × 10^-4 for total fractures; 1.5 × 10^-4 for other fractures). There were significant interactions of VAT^ and BMI on heel BMD and fracture risks in men only (P for VAT^-BMI interaction = 5.9 × 10^-31 for heel BMD; 2.7 × 10^-4 for total fractures; 5.7 × 10^-3 for hip fractures; 6.8 × 10^-3 for other fractures). In two-sample MR analyses, evidence of causality was not observed between VAT^ and DXA-derived BMD or fractures.

CONCLUSIONS

These novel findings demonstrated gender-dependent associations of VAT^ with BMD and fracture risk, with the association in men being modified by adiposity. Evidence of causality was not observed, suggesting that the observational association of VAT^ with BMD and fracture risk could be the result of confounding.

Is it time to consider population screening for fracture risk in postmenopausal women? A position paper from the International Osteoporosis Foundation Epidemiology/Quality of Life Working Group

The IOF Epidemiology and Quality of Life Working Group has reviewed the potential role of population screening for high hip fracture risk against well-established criteria. The report concludes that such an approach should strongly be considered in many health care systems to reduce the burden of hip fractures.

INTRODUCTION

The burden of long-term osteoporosis management falls on primary care in most healthcare systems. However, a wide and stable treatment gap exists in many such settings; most of which appears to be secondary to a lack of awareness of fracture risk. Screening is a public health measure for the purpose of identifying individuals who are likely to benefit from further investigations and/or treatment to reduce the risk of a disease or its complications. The purpose of this report was to review the evidence for a potential screening programme to identify postmenopausal women at increased risk of hip fracture.

METHODS

The approach took well-established criteria for the development of a screening program, adapted by the UK National Screening Committee, and sought the opinion of 20 members of the International Osteoporosis Foundation's Working Group on Epidemiology and Quality of Life as to whether each criterion was met (yes, partial or no). For each criterion, the evidence base was then reviewed and summarized.

RESULTS AND CONCLUSION

The report concludes that evidence supports the proposal that screening for high fracture risk in primary care should strongly be considered for incorporation into many health care systems to reduce the burden of fractures, particularly hip fractures. The key remaining hurdles to overcome are engagement with primary care healthcare professionals, and the implementation of systems that facilitate and maintain the screening program.

Performance of the Garvan Fracture Risk Calculator in Individuals with Diabetes: A Registry-Based Cohort Study

Diabetes increases fracture and falls risks. We evaluated the performance of the Garvan fracture risk calculator (FRC) in individuals with versus without diabetes. Using the population-based Manitoba bone mineral density (BMD) registry, we identified individuals aged 50-95 years undergoing baseline BMD assessment from 1 September 2012, onwards with diabetes and self-reported falls in the prior 12 months. Five-year Garvan FRC predictions were generated from clinical risk factors, with and without femoral neck BMD. We identified non-traumatic osteoporotic fractures (OF) and hip fractures (HF) from population-based data to 31 March 2018. Fracture risk stratification was assessed from area under the receiver operating characteristic curves (AUROC). Cox regression analysis was performed to examine the effect of diabetes on fractures, adjusted for Garvan FRC predictions. The study population consisted of 2618 women with and 14,064 without diabetes, and 636 and 2201 men with and without the same, respectively. The Garvan FRC provided significant OF and HF risk stratification in women with diabetes, similar to those without diabetes. Analyses of OF in men were limited by smaller numbers; no significant difference was evident by diabetes status. Cox regression showed that OF risk was 23% greater in women with diabetes adjusted for Garvan FRC including BMD (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.01-1.49), suggesting it slightly underestimated risk; a non-significant increase in diabetes-related HF risk was noted (HR 1.37, 95% CI 0.88-2.15). Garvan FRC shows similar fracture risk stratification in individuals with versus without diabetes, but may underestimate this risk.

UK clinical guideline for the prevention and treatment of osteoporosis

The National Osteoporosis Guideline Group (NOGG) has revised the UK guideline for the assessment and management of osteoporosis and the prevention of fragility fractures in postmenopausal women, and men age 50 years and older. Accredited by NICE, this guideline is relevant for all healthcare professionals involved in osteoporosis management.

INTRODUCTION

The UK National Osteoporosis Guideline Group (NOGG) first produced a guideline on the prevention and treatment of osteoporosis in 2008, with updates in 2013 and 2017. This paper presents a major update of the guideline, the scope of which is to review the assessment and management of osteoporosis and the prevention of fragility fractures in postmenopausal women, and men age 50 years and older.

METHODS

Where available, systematic reviews, meta-analyses and randomised controlled trials were used to provide the evidence base. Conclusions and recommendations were systematically graded according to the strength of the available evidence.

RESULTS

Review of the evidence and recommendations are provided for the diagnosis of osteoporosis, fracture-risk assessment and intervention thresholds, management of vertebral fractures, non-pharmacological and pharmacological treatments, including duration and monitoring of anti-resorptive therapy, glucocorticoid-induced osteoporosis, and models of care for fracture prevention. Recommendations are made for training; service leads and commissioners of healthcare; and for review criteria for audit and quality improvement.

CONCLUSION

The guideline, which has received accreditation from the National Institute of Health and Care Excellence (NICE), provides a comprehensive overview of the assessment and management of osteoporosis for all healthcare professionals involved in its management. This position paper has been endorsed by the International Osteoporosis Foundation and by the European Society for the Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases.

Thyroid and bone turnover markers in type 2 diabetes: results from the METAL study

OBJECTIVE

We aimed to evaluate whether thyroid hormones, autoimmune and thyroid homeostasis status were related to bone turnover in type 2 diabetes.

METHODS

The data were obtained from a cross-sectional study, the METAL study. In this study, 4209 participants (2059 men and 2150 postmenopausal women) with type 2 diabetes were enrolled. Thyroid function, thyroid antibodies and three bone turnover markers (BTMs), including a large N-mid fragment of osteocalcin (N-MID osteocalcin), β-C-terminal cross-linked telopeptides of type I collagen (β-CTX) and procollagen type I N-terminal propeptide (P1NP), were measured. Thyroid homeostasis parameters, including the sum activity of step-up deiodinases (SPINA-GD), thyroid secretory capacity (SPINA-GT), Jostel's TSH index (TSHI) and the thyrotroph thyroid hormone resistance index (TTSI), were calculated. The associations of thyroid parameters with BTMs were analyzed using linear regression.

RESULTS

Free and total triiodothyronine were positively associated with N-MID osteocalcin and P1NP in both sexes and positively associated with β-CTX in postmenopausal women. Thyroid-stimulating hormone was negatively associated with β-CTX in postmenopausal women, and free thyroxine was negatively associated with N-MID osteocalcin and P1NP in men. SPINA-GD was positively associated with N-MID osteocalcin and P1NP in both sexes. There was a positive relationship of SPINA-GT with β-CTX, a negative relationship of TTSI with β-CTX, and a negative relationship of TSHI with β-CTX and P1NP in postmenopausal women.

CONCLUSIONS

Among men and postmenopausal women with type 2 diabetes, significant associations were observed between N-MID osteocalcin, β-CTX and P1NP with thyroid function and thyroid homeostasis. Further prospective studies are warranted to understand the causal relationship and underlying mechanism.

Bone density in youth with prediabetes: results from the National Health and Nutrition Examination Survey, 2005-2006

Youth with type 2 diabetes might have suboptimal peak bone mass, but it is unknown whether similar effects are evident in youth with prediabetes. Results from this study suggest that diabetes-related effects on peak bone mass likely occur before disease onset, and involve the muscle-bone unit.

INTRODUCTION

Type 2 diabetes might adversely influence bone health around the age of peak bone mass, but it is unknown whether diabetes-related effects on areal bone mineral density (aBMD) are evident in youth with prediabetes. We compared age-related trends in aBMD and associations between lean body mass (LBM) and aBMD between children and adolescents with prediabetes vs. normal glucose regulation.

METHODS

Cross-sectional analysis of data from the National Health and Nutrition Examination Survey (2005-2006) in youth ages 12-20 years (49% female, 34% black) with prediabetes (n = 267) and normal glucose regulation (n = 1664). Whole body aBMD and LBM were assessed via DXA. LBM index (LBMI) and Z-scores for aBMD and LBMI were computed.

RESULTS

Unadjusted between-group comparisons revealed greater mean weight and LBMI Z-scores in youth with prediabetes vs. normal glucose regulation, but similar bone Z-scores between the two groups. While accounting for differences in BMI Z-score, there was a significant interaction between prediabetes status and age with respect to whole body aBMD Z-score (P < 0.05), such that children with prediabetes tended to have increased aBMD but adolescents and young adults with prediabetes tended have lower aBMD. Furthermore, the positive association between LBMI and whole body aBMD was moderated in youth with prediabetes (P < 0.001), who had slightly lower whole body aBMD for a given LBMI (P = 0.068). Lumbar spine bone measures did not differ between the two groups.

CONCLUSIONS

Type 2 diabetes-related threats to peak bone mass might occur prior to disease onset, therefore potentially impacting a considerable proportion of US youth.

Disparities in osteoporosis care among postmenopausal women in the United States

Osteoporosis and fragility fractures result in significant morbidity and mortality and contribute to substantial healthcare costs. Despite being a treatable disease, osteoporosis remains both underdiagnosed and undertreated in the US general population, with significant disparities in care between non-White and White women. These disparities are evident from screening to post-fracture treatment. Non-White women are less likely to be screened for osteoporosis, to be prescribed pharmacotherapy, or to receive treatment post-fracture; furthermore, the mortality rate after fracture is higher in non-White women. Given existing diagnostic and treatment disparities, additional studies and interventions are needed to optimize the bone health of Asian, Black, Hispanic, and Native American women, and to reduce morbidity and mortality from osteoporosis and fragility fractures.

Risk Factors for Fracture in Patients with Coexisting Chronic Kidney Disease and Type 2 Diabetes: An Observational Analysis from the CREDENCE Trial

BACKGROUND

The fracture pathophysiology associated with type 2 diabetes and chronic kidney disease (CKD) is incompletely understood. We examined individual fracture predictors and prediction sets based on different pathophysiological hypotheses, testing whether any of the sets improved prediction beyond that based on traditional osteoporotic risk factors.

METHODS

Within the CREDENCE cohort with adjudicated fracture outcomes, we assessed the association of individual factors with fracture using Cox regression models. We used the Akaike information criteria (AIC) and Schwartz Bayes Criterion (SBC) to assess six separate variable sets based on hypothesized associations with fracture, namely, traditional osteoporosis, exploratory general population findings, cardiovascular risk, CKD-mineral and bone disorder, diabetic osteodystrophy, and an all-inclusive set containing all variables.

RESULTS

Fracture occurred in 135 (3.1%) participants over a median 2.35 [1.88-2.93] years. Independent fracture predictors were older age (hazard ratio [HR] 1.04, confidence interval [CI] 1.01-1.06), female sex (HR 2.49, CI 1.70-3.65), previous fracture (HR 2.30, CI 1.58-3.34), Asian race (HR 1.74, CI 1.09-2.78), vitamin D therapy requirement (HR 2.05, CI 1.31-3.21), HbA1c (HR 1.14, CI 1.00-1.32), prior cardiovascular event (HR 1.60, CI 1.10-2.33), and serum albumin (HR 0.41, CI 0.23-0.74) (lower albumin associated with greater risk). The goodness of fit of the various hypothesis sets was similar (AIC range 1870.92-1849.51, SBC range 1875.60-1948.04).

CONCLUSION

Independent predictors of fracture were identified in the CREDENCE participants with type 2 diabetes and CKD. Fracture prediction was not improved by models built on alternative pathophysiology hypotheses compared with traditional osteoporosis predictors.

Calcitriol-enhanced autophagy in gingival epithelium attenuates periodontal inflammation in rats with type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM)-associated periodontitis is a common disease with high prevalence, associated with persistent infection and complicated manifestations. Calcitriol (1 alpha, 25-dihydroxyvitamin D3, 1,25D) is the active form of vitamin D that plays a protective role in immune regulation, bone metabolism, and inflammatory response. In this study, we constructed a T2DM model in rats by combining a high-fat diet with low-dose streptozotocin. The periodontitis model in rats was developed by ligation and Porphyromonas gingivalis (ATCC 33277) inoculation. Rats were randomly divided into five groups: non-diabetic blank, diabetic blank, diabetes with calcitriol treatment, diabetes with 3-methyladenine (3-MA) treatment, or diabetes with calcitriol and 3-MA treatment. The diabetic rats exhibited an intense inflammatory response and decreased autophagy compared with the non-diabetic rats. Intraperitoneal injection of calcitriol and autophagy inhibitor (3-MA) allowed us to explore the effect of calcitriol on inflammation in the gingival epithelium and the role of autophagy in this process. Treatment with calcitriol resulted in the decreased expression of NFκB-p65, p62/SQSTM1 and inflammatory response and increased expression of LC3-II/LC3-I. Application of 3-MA significantly suppressed autophagy, which was apparently retrieved by calcitriol. Antibacterial peptide (LL-37) is the only antimicrobial peptide in the cathelicidin family that is found in the human body, and it exhibits a broad spectrum of antibacterial activity and regulates the immune system. In the present study, our findings indicated that calcitriol-enhanced autophagy may attenuated periodontitis and the decrease of LL-37 was rescued by calcitriol treatment in the gingival epithelial cells of T2DM rats. Our study provides evidence for the application of calcitriol as an adjunctive treatment for T2DM-associated periodontitis.

Differential risk of fracture attributable to type 2 diabetes mellitus according to skeletal site

BACKGROUND

Impaired bone quality, especially related to accumulation of advanced glycation end-products (AGEs) and higher incidence of falls contribute substantially to a higher risk of fracture associated with type 2 diabetes mellitus (T2DM). These factors may predispose to fractures more at skeletal sites where impaired bone toughness and falls play a larger pathogenic role (such as hip fractures) compared to skeletal sites where they are less important (such as vertebral fractures).

OBJECTIVE

To determine if the associations of T2DM with prevalent and incident vertebral fractures are as strong as they are for hip and other non-vertebral fractures.

METHODS

Amongst 80,238 individuals in the Manitoba Bone Density Program database (mean [SD] age 64.4 [11.1] years, 89.8% female, 8676 with diagnosed T2DM) with a baseline BMD test (1996-2016), we estimated hazard ratios (HRs) for incident clinical fracture at different skeletal sites in those with compared to those without T2DM using Cox proportional hazards models over a mean (SD) 9.0 (5.0) year follow-up period. We also estimated odds ratios for prevalent vertebral fracture on VFA images amongst 9594 individuals (mean [SD] 76 [6.8] years, 1185 with T2DM diagnosis at time of DXA-VFA) and for prior clinical fractures at different skeletal sites using logistic regression models.

RESULTS

After multivariable adjustment, T2DM was associated with incident hip (HR 1.63, 95% CI 1.44 to 1.85) and proximal humerus fractures (HR 1.59, 95% CI 1.39 to 1.83), but was not associated with incident forearm fracture (HR 1.00, 95% CI 0.86 to 1.17) and only weakly with incident clinical vertebral fracture (HR 1.16, 95% CI 1.01 to 1.33). Similarly, T2DM was associated with prior hip (OR 1.78, 95% CI 1.21 to 2.61) and prior proximal humerus fracture (OR 1.31, 95% CI 1.02 to 1.68) but not with prior forearm (OR 0.89, 95% CI 0.74 to 1.06) or prevalent vertebral fracture on VFA images (OR 0.91, 95% CI 0.77 to 1.08).

CONCLUSION

T2DM is a stronger risk factor for hip and proximal humerus fractures than for vertebral and wrist fractures. Further research is warranted to determine if the known differences in falls and/or bone quality between T2DM and age-related osteoporosis account for these differential associations.

Comparison of Bone Mineral Density in US Adults With Diabetes, Prediabetes and Normoglycemia From 2005 to 2018

BACKGROUND

Accumulating evidence has shown that diabetes has an impact on bone metabolism with conflicting results. Furthermore, little is known about the relationship of prediabetes with bone mineral density (BMD). Therefore, we explored the association between BMD and glucometabolic status in adults in the US.

METHODS

In this cross-sectional study, we extracted and analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. A total of 14610 subjects aged 40 ≥ years diagnosed with diabetes, prediabetes, or normal glucose regulation (NGR) and had available data on BMD were eligible.

RESULTS

The prevalence of prediabetes and diabetes in US adults aged 40 ≥ years were 39.2% and 26.4%, respectively. After multivariable adjustment, we found an increasing trend of BMD at the total hip, femoral neck, and lumbar spine with glucometabolic conditions from NGR and prediabetes to diabetes in adults aged ≥ 40 years in the US. This trend was more prominent in women than that in men. Fasting plasma glucose (FPG) and HbA1c levels were also positively correlated with BMD.

CONCLUSIONS

Glucometabolic conditions were significantly associated with BMD values in US adults.

Comparison of fracture risk between type 1 and type 2 diabetes: a comprehensive real-world data

Population-based cohort study of 6,548,784 Korean subjects demonstrates that the risk of fracture was higher in patients with diabetes than in nondiabetic subjects. Furthermore, patients with type 1 diabetes were associated with a higher risk of fracture than patients with type 2 diabetes for all measurement sites.

INTRODUCTION

Diabetes mellitus is associated with increased fracture risk. Although the pathophysiologic effect on bone metabolism differs according to the type of diabetes, a higher risk of fracture in patients with diabetes than in nondiabetic patients has been consistently demonstrated. Considering the ever-increasing number of patients with diabetes, we aimed to provide updated information on whether this phenomenon remains valid in real-world settings by using large-scale population datasets.

METHODS

We conducted a retrospective longitudinal study using data from the Korean National Health Insurance Service dataset of preventive health check-ups between January 2009 and December 2016. The hazard ratios were calculated for any fracture, vertebral fracture, and hip fracture and were analyzed according to the presence and type of diabetes. Among 10,585,818 subjects, 6,548,784 were eligible for the analysis (2418 patients with type 1 diabetes mellitus [T1DM] and 506,208 patients with type 2 diabetes mellitus [T2DM]).

RESULTS

The mean follow-up duration (in years) was 7.0 ± 1.3 for subjects without diabetes, 6.4 ± 2.0 for those with T1DM, and 6.7 ± 1.7 for T2DM. Patients with T1DM had a higher incidence rate for all types of fractures per 1000 person-years. The fully adjusted hazard ratios (HRs) for any fracture, vertebral fracture, and hip fracture were higher in T1DM than in T2DM (1.37 [95% confidence interval (CI): 1.23-1.52] for any fracture, 1.33 [95% CI: 1.09-1.63] for vertebral fracture, and 1.99 [95% CI: 1.56-2.53] for hip fracture).

CONCLUSIONS

In this large-scale population analysis, diabetes was associated with a higher risk of all types of fractures. Patients with T1DM had a higher risk of fracture than those with T2DM for all measurement sites, and hip fractures had the highest risk. Therefore, fracture prevention training for patients with diabetes is advisable.

Long-term bisphosphonate therapy and atypical femoral fracture: Can you have too much of a good thing?

The long-term, continuous use of bisphosphonates (beyond 5 years) is not wholly without risk. Atypical femoral fracture is an uncommon but potentially very serious adverse event associated with the long-term use of bisphosphonates. Here we consider the complexities of long-term bisphosphonate prescribing, particularly in those that are low risk of osteoporotic fracture, wherein the duration of therapy should be reviewed regularly with individualised risk assessment to ensure the duration of treatment is appropriate.

Comparative effectiveness and safety of sodium-glucose cotransporter-2 inhibitors versus metformin in patients with type 2 diabetes: An observational study using data from routine care

AIM

To assess the effectiveness and safety of sodium-glucose cotransporter-2 (SGLT2) inhibitors in treatment-naïve patients compared with metformin.

PARTICIPANTS AND METHODS

We conducted a cohort study of US adults with type 2 diabetes mellitus who had not filled a prescription for a diabetes medication in the preceding year. We then identified patients who newly filled a prescription for an SGLT2 inhibitor or metformin between 2013 and 2018. The primary outcome was a composite of heart failure, myocardial infarction or stroke. Safety outcomes included hypoglycaemia, diabetic ketoacidosis, genital infection, lactic acidosis and acute kidney injury. After 1:1 propensity-score (PS) matching, proportional hazards models were fit to estimate hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

We identified 9964 individuals newly prescribed an SGLT2 inhibitor who were PS-matched to 9964 individuals newly prescribed metformin. The mean age was 54 years, 52% were women, and the duration of follow-up was 213 days for metformin and 147 days for SGLT2 inhibitors. The primary outcome occurred in 54 patients (7.2 events per 1000 person-years) who received an SGLT2 inhibitor, compared to 84 patients (8.5 per 1000 person-years) who received metformin (HR  0.82, 95% CI 0.58, 1.15). Similar results (HR 0.87, 95% CI 0.69, 1.09) were observed in an analysis with longer follow-up (ie, approximately 600 days). The rates of genital infection (HR 2.28, 95% CI 1.87, 2.78) and diabetic ketoacidosis (HR 1.58, 95% CI 0.92, 2.70) were higher for patients prescribed an SGLT2 inhibitor compared to metformin, while the rates of acute kidney injury (HR 0.94, 95% CI 0.60, 1.47) or hypoglycaemia (HR 0.83, 95% CI 0.48, 1.42) were not.

CONCLUSIONS

We observed a numerically lower rate of short-/mid-term cardiovascular events for patients newly prescribed an SGLT2 inhibitor compared to metformin, albeit with wide CIs that include the possibility of a null effect. SGLT2 inhibitors were associated with a higher rate of genital infection and diabetic ketoacidosis. Larger cohort studies and long-term clinical trials powered to assess cardiovascular events are necessary to understand the risk-benefit profile of SGLT2 inhibitors as first-line therapy for adults with type 2 diabetes mellitus.

Lower trabecular bone score in type 2 diabetes mellitus: A role for fat mass and insulin resistance beyond hyperglycaemia

AIMS

To examine the clinical and biochemical determinants of trabecular bone score (TBS) in type 2 diabetes mellitus (T2DM) patients.

METHODS

Cross-sectional observational study in 137 T2DM patients (49-85 years). Whole-body fat percentage was estimated using the relative fat mass (RFM) equation. Bone mineral density (BMD) and TBS were assessed using dual-energy X-ray absorptiometry and TBS iNsight Software respectively.

RESULTS

T2DM patients showed significantly lower TBS values (P < 0.001) despite significantly higher lumbar spine BMD (LS-BMD) (P = 0.025) compared to controls. TBS values ​​were negatively correlated with body mass index (BMI) (P < 0.001), waist circumference (P < 0.001), and HOMA-2IR index (P = 0.004) and positively correlated with sex hormone-binding globulin (SHBG) (P = 0.01) and LS-BMD (P = 0.003). RFM was negatively associated with TBS in both males (P < 0.001) and females (P = 0.005). The multivariate analysis showed that RFM, HOMA2-IR (negative), SHBG, and LS-BMD (positive) were the variables independently associated with TBS. ROC analysis revealed RFM as the variable with the highest predictive value for risk of degraded bone microarchitecture.

CONCLUSIONS

The adiposity estimated by RFM may negatively affect TBS and this relationship may be influenced by insulin resistance and SHBG. RFM could act as a key estimator of degraded bone microarchitecture risk in the T2DM population.

Identifying Risk Factors for Diabetic Ketoacidosis Associated with SGLT2 Inhibitors: a Nationwide Cohort Study in the USA

INTRODUCTION

Sodium glucose co-transporter-2 inhibitors (SGLT2) are commonly prescribed to patients with type 2 diabetes mellitus, but can increase the risk of diabetic ketoacidosis. Identifying patients prone to diabetic ketoacidosis may help mitigate this risk.

METHODS

We conducted a population-based cohort study of adults initiating SGLT2 inhibitor use from 2013 through 2017. The primary objective was to identify potential predictors of diabetic ketoacidosis. Two machine-learning methods were applied to model high-dimensional pre-exposure data: gradient boosted trees and least absolute shrinkage and selection operator (LASSO) regression. We rank ordered the variables produced from LASSO by the size of their estimated coefficient (largest to smallest). With gradient boosted trees, a relative importance measure for each variable is provided rather than a coefficient. The "top variables" were identified after reviewing the distributions of the effect estimates from LASSO and gradient boosted trees to identify where there was a substantial decrease in variable importance. The identified predictors were then assessed in a logistic regression model and reported as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

We identified 111,442 adults who started SGLT2 inhibitor use. The mean age was 57 years, 44% were female, the mean hemoglobin A1C was 8.7%, and the mean creatinine was 0.89 mg/dL. During a mean follow-up of 180 days, 192 patients (0.2%, i.e., 2 per 1000) were diagnosed and hospitalized with diabetic ketoacidosis (DKA) and 475 (0.4%, i.e., 4 per 1000) were diagnosed in either an inpatient or outpatient setting. Using gradient boosted trees, the strongest predictors were prior DKA, baseline hemoglobin A1C level, baseline creatinine level, use of medications for dementia, and baseline bicarbonate level. Using LASSO regression not including laboratory test results due to missing data, the strongest predictors were prior DKA, digoxin use, use of medications for dementia, and recent hypoglycemia. The logistic regression model incorporating the variables identified from gradient boosted trees and LASSO regression suggested the following pre-exposure characteristics had the strongest association with a hospitalization for DKA: use of dementia medications (OR = 7.76, 95% CI 2.60, 23.1), prior intracranial hemorrhage (OR = 11.5, 95% CI 1.46, 91.1), a prior diagnosis of hypoglycemia (OR = 5.41, 95% CI 1.92,15.3), prior DKA (OR = 2.45, 95% CI 0.33, 18.0), digoxin use (OR = 4.00, 95% CI 1.21, 13.2), a baseline hemoglobin A1C above 10% (OR = 3.14, 95% CI 1.95, 5.06), and baseline bicarbonate below 18 mmol/L (OR 5.09, 95% CI 1.58, 16.4).

CONCLUSION

Diabetic ketoacidosis affected approximately 2 per 1000 patients starting to use an SGLT2 inhibitor. We identified both anticipated, e.g., low baseline serum bicarbonate, and unanticipated, e.g., digoxin, dementia medications, risk factors for SGLT2 inhibitor-induced DKA.

Undenatured Type II Collagen Relieves Bone Impairment through Improving Inflammation and Oxidative Stress in Ageing db/db Mice

Ageing-related bone impairment due to exposure to hyperglycemic environment is scarcely researched. The aim was to confirm the improvement effects of undenatured type II collagen (UC II) on bone impairment in ageing db/db mice, and the ageing model was established by normal feeding for 48-week-old. Then, the ageing db/db mice were randomly assigned to UC II intervention, the ageing model, and the chondroitin sulfate + glucosamine hydrochloride control groups. After 12 weeks of treatment, femoral microarchitecture and biomechanical parameters were observed, biomarkers including bone metabolism, inflammatory cytokines, and oxidative stress were measured, and the gastrocnemius function and expressions of interleukin (IL) 1β, receptor activator of nuclear factor (NF)-κB ligand (RANKL), and tartrate-resistant acid phosphatase (TRAP) were analyzed. The results showed that the mice in the UC II intervention group showed significantly superior bone and gastrocnemius properties than those in the ageing model group, including bone mineral density (287.65 ± 72.77 vs. 186.97 ± 32.2 mg/cm³), gastrocnemius index (0.46 ± 0.07 vs. 0.18 ± 0.01%), muscle fiber diameter (0.0415 ± 0.005 vs. 0.0330 ± 0.002 mm), and cross-sectional area (0.0011 ± 0.00007 vs. 0.00038 ± 0.00004 mm²). The UC II intervention elevated bone mineralization and formation and decreased bone resorption, inflammatory cytokines, and the oxidative stress. In addition, lower protein expression of IL-1β, RANKL, and TRAP in the UC II intervention group was observed. These findings suggested that UC II improved bones impaired by T2DM during ageing, and the likely mechanism was partly due to inhibition of inflammation and oxidative stress.

Comparison of the Effects of Various Antidiabetic Medication on Bone Mineral Density in Patients with Type 2 Diabetes Mellitus

BACKGROUND

Prospective comparative studies on the effects of various antidiabetic agents on bone metabolism are limited. This study aimed to assess changes in bone mass and biochemical bone markers in postmenopausal patients with type 2 diabetes mellitus (T2DM).

METHODS

This prospective, multicenter, open-label, comparative trial included 264 patients with T2DM. Patients who had received a metformin, or sulfonylurea/metformin combination (Group 1); a thiazolidinedione combination (Group 2); a dipeptidyl peptidase-4 inhibitor (gemigliptin) combination (Group 3); or an sodium-glucose cotransporter 2 inhibitor (empagliflozin) combination (Group 4) were prospectively treated for 12 months; bone mineral density (BMD) and bone turnover marker (BTM) changes were evaluated.

RESULTS

The femoral neck BMD percentage changes were -0.79%±2.86% (Group 1), -2.50%±3.08% (Group 2), -1.05%±2.74% (Group 3), and -1.24%±2.91% (Group 4) (P<0.05). The total hip BMD percentage changes were -0.57%±1.79% (Group 1), -1.74%±1.48% (Group 2), -0.75%±1.87% (Group 3), and -1.27%±1.72% (Group 4) (P<0.05). Mean serum BTM (C-terminal type 1 collagen telopeptide and procollagen type 1 amino-terminal propeptide) levels measured during the study period did not change over time or differ between groups.

CONCLUSION

Significant bone loss in the femoral neck and total hip was associated with thiazolidinedione combination regimens. However, bone loss was not significantly associated with combination regimens including gemigliptin or empagliflozin. Caution should be exercised during treatment with antidiabetic medications that adversely affect the bone in patients with diabetes at a high risk of bone loss.

The effect of diabetes mellitus on the shear bond strength of composite resin to dentin and enamel

Diabetes mellitus might be linked to the deterioration of certain physical properties of dentin and enamel. This study aimed to determine the effect of two types of diabetes on the shear bond strength of enamel and dentin, by using the single bond universal bonding system. Sixty specimens [from 15 teeth; 5 from each group-non-diabetic (ND), Diabetic type I (D1), and Diabetic type II (D2)], were prepared with equal amounts of dentin (n = 5) and enamel (n = 5). Enamel specimens (E20) were etched with 37% phosphoric acid, for 20 s, and dentin specimens (D15) were etched for 15 s. A standard shear bond strength test was performed on all specimens. Their failure modes were also studied under a scanning electron microscope, and the data were analyzed by using ANOVA and Post Hoc Tukey's test (a = 0.050). For the enamel groups, significant differences were only noticed between the ND and D1 (P < 0.050) groups, and between the ND and D2 (P < 0.050) groups. In the dentin groups, there was a significant difference only between the ND and D1 (P < 0.050) groups. The micrographs showed that the ND group had the highest number of specimens with cohesive failure and D1 had the highest number of specimens with adhesive failure. It can be concluded that both types of diabetes reduce the shear bond strength of composite resin on dentin and enamel. However, it seems that the negative effect of diabetes on shear bond strength of dental composite resin is more drastic in individuals with type I diabetes as compared with type II.

Management of bone fragility in type 2 diabetes: Perspective from an interdisciplinary expert panel

AIM

Bone fragility is increasingly recognized as a relevant complication of type 2 diabetes (T2D) and diabetic patients with fragility fractures have higher mortality rates than non diabetic individuals or diabetic patients without fractures. However, current diagnostic approaches for fracture risk stratification, such as bone mineral density measurement or the use of risk assessment algorithms, largely underestimate fracture risk in T2D patients. A multidisciplinary expert panel was established in order to in order to formulate clinical consensus recommendations on bone health assessment and management of fracture risk in patients with T2D.

DATA SYNTHESIS

The following key questions were addressed: a) which are the risk factors for bone fragility in T2D?, b) which diagnostic procedures can be currently used to stratify fracture risk in T2D patients?, c) which are the effects of antidiabetic treatments on bone?, and d) how to prevent and treat bone fragility in T2D patients? Based on the available data members of this panel suggest that the stratification of fracture risk in patients with diabetes should firstly rely on the presence of a previous fragility fracture and on the individual risk profile, with the inclusion of T2D-specific risk factors (namely T2D duration above 10 yrs, presence of chronic T2D complications, use of insulin or thiazolidinediones and persistent HbA1c levels above 8% for at least 1 year). Two independent diagnostic approaches were then suggested in the presence or the absence of a prevalent fragility fracture, respectively.

CONCLUSIONS

Clinical trials in T2D patients at risk for fragility fractures are needed to determine the efficacy and safety of available antiresorptive and anabolic agents in this specific setting.

Fracture behavior of human cortical bone: Role of advanced glycation end-products and microstructural features

Diabetes is associated with increased fracture risk in human bone, especially in the elderly population. In the present study, we investigate how simulated advanced glycation end-products (AGEs) and materials heterogeneity affect crack growth trajectory in human cortical bone. We used a phase field fracture framework on 2D models of cortical microstructure created from human tibias to analyze crack propagation. The increased AGEs level results in a higher rate of crack formation. The simulations also indicate that the mismatch between the fracture properties (e.g., critical energy release rate) of osteons and interstitial tissue can alter the post-yielding behavior. The results show that if the critical energy release rate of cement lines is lower than that of osteons and the surrounding interstitial matrix, cracks can be arrested by cement lines. Additionally, activation of toughening mechanisms such as crack merging and branching depends on bone microstructural morphology (i.e., osteons geometrical parameters, canals, and lacunae porosities). In conclusion, the present findings suggest that materials heterogeneity of microstructural features and the crack-microstructure interactions can play important roles in bone fragility.

Beneficial effects of switching to denosumab from bisphosphonates or selective estrogen receptor modulators in postmenopausal women with type 2 diabetes and osteopenia/osteoporosis

AIMS/INTRODUCTION

Patients with type 2 diabetes mellitus have a higher bone fracture risk than patients without diabetes. Although denosumab (Dmab) is a potent bone resorption inhibitor, its efficacy in patients with type 2 diabetes mellitus has not been elucidated. In this study, we investigated the effects of switching to Dmab from bisphosphonates (BP) or a selective estrogen receptor modulator (SERM) in postmenopausal type 2 diabetes mellitus patients.

MATERIALS AND METHODS

This was a three medical institutions, prospective, observational study for postmenopausal patients with type 2 diabetes mellitus whose T-score of femoral neck or lumbar spine bone mineral density was under -1.0 standard deviation, even after >6 months of BP or SERM administration. After obtaining consent, participants were treated for osteopenia/osteoporosis by either continuing BP (BP-BP group)/SERM (SERM-SERM group), or by switching to Dmab (BP-Dmab or SERM-Dmab groups). Changes in bone mineral density and bone metabolism marker levels were evaluated after 6 months.

RESULTS

A total of 48 patients were included in this study, and each group comprised 12 patients. No significant difference existed in baseline characteristics among the groups. The average age and glycated hemoglobin were 71 ± 8 years and 7.2 ± 0.9%, respectively. In the SERM-Dmab group, lumbar spine bone mineral density was significantly increased by 5.0% compared with the SERM-SERM group (P < 0.04). Serum bone-specific alkaline phosphatase and tartrate-resistant acid phosphatase 5b were significantly decreased in the BP-Dmab and SERM-Dmab groups compared with the BP-BP and SERM-SERM groups, respectively.

CONCLUSIONS

Switching to Dmab from BP or SERM is beneficial to prevent osteoporosis progression in postmenopausal patients with type 2 diabetes mellitus patients.

Comparison of methods to improve fracture risk assessment in chinese diabetic postmenopausal women: a case-control study

PURPOSE

This study evaluated the predictive power of adjusted FRAX and standard FRAX models based on the actual prevalence of osteoporosis in type 2 diabetic (T2DM) postmenopausal women, and to explore the optimal strategy to better predicted fracture risk in postmenopausal women with diabetes in China.

METHODS

We recruited 434 patients from community-medical centers, 217 with T2DM and 217 without T2DM (non-T2DM). All participants completed self-reported questionnaires detailing their characteristics and risk factors. Bone mineral density (BMD) and spinal radiographs were evaluated. The China FRAX model calculated all scores. The area under the receiver operator characteristic curve (ROC-AUC) evaluated the sensitivity, specificity, and accuracy for predicting 10-year risk for major (MOF) and hip (OHF) osteoporotic fractures in T2DM patients.

RESULTS

T2DM patients had higher BMD but lower average FRAX values than non-T2DM patients. The unadjusted FRAX ROC-AUC was 0.774, significantly smaller than that for 0.5-unit femoral neck T-score-adjusted FRAX (0.800; p = 0.004). Rheumatoid arthritis (RA; AUC = 0.810, p = 0.033) and T-score (AUC = 0.816, p = 0.002) adjustments significantly improved fracture prediction in T2DM patients.

CONCLUSIONS

Femoral neck T-score adjustment might be the preferred method for predicting MOF and OHF in Chinese diabetic postmenopausal women, while RA adjustment only effectively predicted HF risk.

Increasing fasting glucose and fasting insulin associated with elevated bone mineral density-evidence from cross-sectional and MR studies

We performed a cross-sectional study using the National Health Examination and Nutrition Survey (NHANES) data and a Mendelian randomisation (MR) study using the GWAS summary statistics from European populations. The T2D-related indices (fasting plasma glucose (FPG), fasting insulin (FI), and insulin resistance (IR)) were found to associate with elevated bone mineral density (BMD).

INTRODUCTION

The known associations amongst FPG, FI, IR, and BMD remain inconsistent. This study aims to explore the abovementioned associations by using cross-sectional and MR designs.

METHODS

Data from adults aged ≥ 20 years (n = 7170) in four rounds of the U.S. NHANES (2005-2010 and 2013-2014) were analysed in this cross-sectional study. Multiple linear and logistic regression models were used for statistical analyses. A two-sample MR study was performed using the genome-wide association study summary statistics obtained from the Meta-analyses of Glucose and Insulin-related traits Consortium (n = 108,557) and Genetic Factors for Osteoporosis Consortium (n = 32,735) to examine the causality of the FI-BMD association.

RESULTS

Multiple linear regression revealed that FPG was positively associated with the BMDs at the hip, femur neck, and 1st lumbar spine (L1). Multiple logistic regressions revealed that FPG levels were associated with elevated BMDs at the hip and L1, and FI and IR levels were associated with elevated BMD at the hip. Patients with type 2 diabetes had higher hip BMD than those without diabetes. In the MR study, the lumbar spine BMD increased by 0.49 g/cm² (95% confidence interval: 0.01, 0.97) in response to per unit increase in log-transformed FI.

CONCLUSION

Findings from our cross-sectional and MR studies revealed the associations between the studied diabetic indices and BMD measurements in the US and European adults.

Alterations of bone markers in obese patients with type 2 diabetes after bariatric surgery: A meta-analysis and systemic review of randomized controlled trials and cohorts

BACKGROUND

The aim of this study is to evaluate the alterations in bone mineral density and other surrogate markers for osteoporosis in obese patients with type 2 diabetes mellitus (T2DM) who received Roux-en-Y gastric bypass (RYGB) versus medical treatment as control.

METHODS

We searched 4 electronic databases and reference lists of relevant studies for eligible research published before December, 2019. After quality assessment, eligible studies were synthesized for relevant outcomes, including lumbar spine bone mineral density (L-spine BMD) change, total hip BMD change, osteocalcin level, C-terminal telopeptide level, and parathyroid hormone level.

RESULTS

Three randomized clinical trials and 2 observational studies concerning 307 total obese T2DM patients were included. Follow-up ranged from 12 to 60 months. Patients underwent RYGB surgery were associated with both higher L-spine BMD loss (mean difference: -2.90, 95% CI: -2.99∼-2.81, P < .00001) and total hip BMD loss (mean difference: -5.81, 95% CI: -9.22∼-2.40, P = .0008). As to biochemical markers of bone metabolism, we found significantly higher osteocalcin level in medical treatment (control) group compared with RYGB group (mean difference: 11.16, 95% CI: 8.57-13.75, P < .00001). However, higher C-terminal telopeptide level and parathyroid hormone level were noted in medical treatment group (control) compared with RYGB group (mean difference: 0.29, 95% CI: 0.11-0.48, P = .002; mean difference: 1.56, 95% CI: 0.84-2.27, P < .0001).

CONCLUSIONS

RYGB surgery is associated with negative impact on bone metabolism and increase the risk of osteoporosis in obese patients with T2DM. We suggest that clinicians acknowledge the adverse effects of surgery and keep monitoring bone mineral components in post-RYGB populations. Further studies regarding the optimal amount of perioperative and postsurgical supplementation should be evaluated.

Sodium-glucose co-transporter-2 inhibitors versus dipeptidyl peptidase-4 inhibitors and the risk of heart failure: A nationwide cohort study of older adults with diabetes mellitus

AIMS

To analyse the rate of heart failure hospitalization for older adults prescribed a sodium-glucose co-transporter-2 (SGLT2) inhibitor.

MATERIALS AND METHODS

The study cohort included adults aged 66 years and older diagnosed with diabetes mellitus in Ontario, Canada, between July 2015 and March 2019, who received either an SGLT2 inhibitor or a dipeptidyl peptidase-4 (DPP-4) inhibitor. The primary outcome was a composite of heart failure hospitalization and all-cause mortality. Secondary outcomes included diabetic ketoacidosis and hypoglycaemia.

RESULTS

A total of 29 916 adults prescribed an SGLT2 inhibitor were compared with 29 916 adults prescribed a DPP-4 inhibitor. The mean age was 72 years, 60% were men, the baseline glycated haemoglobin concentration was 8.2% and the baseline creatinine was 89 μmol/L. The incidence rate of the primary outcome was 19/1000 person-years for adults prescribed an SGLT2 inhibitor compared to 38/1000 person-years in those prescribed a DPP-4 inhibitor. This resulted in a hazard ratio (HR) of 0.49 (95% confidence interval [CI] 0.45, 0.54) and a rate difference (RD) of 19 fewer events per 1000 person-years (RD -19 [95% CI -22, -17]). Patients prescribed an SGLT2 inhibitor also had a lower rate of hypoglycaemia (HR 0.61 [95% CI 0.46, 0.81); RD -1.6 [95% CI -2.4, -0.8]), but a higher rate of diabetic ketoacidosis (HR 1.84 [95% CI 1.26, 2.70]; RD 1.0 [95% CI 0.4, 1.6]).

CONCLUSIONS

Older adults prescribed an SGLT2 inhibitor had a lower rate of heart failure hospitalization or death, and a lower rate of hypoglycaemia, but an increased rate of diabetic ketoacidosis compared to older adults prescribed a DPP-4 inhibitor.

Longitudinal Evolution of Bone Microarchitecture and Bone Strength in Type 2 Diabetic Postmenopausal Women With and Without History of Fragility Fractures-A 5-Year Follow-Up Study Using High Resolution Peripheral Quantitative Computed Tomography

Introduction

Diabetic bone disease is characterized by an increased fracture risk which may be partly attributed to deficits in cortical bone quality such as higher cortical porosity. However, the temporal evolution of bone microarchitecture, strength, and particularly of cortical porosity in diabetic bone disease is still unknown. Here, we aimed to prospectively characterize the 5-year changes in bone microarchitecture, strength, and cortical porosity in type 2 diabetic (T2D) postmenopausal women with (DMFx) and without history of fragility fractures (DM) and to compare those to nondiabetic fracture free controls (Co) using high resolution peripheral quantitative computed tomography (HR-pQCT).

Methods

Thirty-two women underwent baseline HR-pQCT scanning of the ultradistal tibia and radius and a FU-scan 5 years later. Bone microarchitectural parameters, including cortical porosity, and bone strength estimates via µFEA were calculated for each timepoint and annualized. Linear regression models (adjusted for race and change in BMI) were used to compare the annualized percent changes in microarchitectural parameters between groups.

Results

At baseline at the tibia, DMFx subjects exhibited the highest porosity of the three groups (66.3% greater Ct.Po, 71.9% higher Ct.Po.Volume than DM subjects, p < 0.022). Longitudinally, porosity increased significantly over time in all three groups and at similar annual rates, while DMFx exhibited the greatest annual decreases in bone strength indices (compared to DM 4.7× and 6.7× greater decreases in failure load [F] and stiffness [K], p < 0.025; compared to Co 14.1× and 22.2× greater decreases in F and K, p < 0.020).

Conclusion

Our data suggest that despite different baseline levels in cortical porosity, T2D women with and without fractures experienced long-term porosity increases at a rate similar to non-diabetics. However, the annual loss in bone strength was greatest in T2D women with a history of a fragility fractures. This suggests a potentially non-linear course of cortical porosity development in T2D bone disease: major porosity may develop early in the course of disease, followed by a smaller steady annual increase in porosity which in turn can still have a detrimental effect on bone strength-depending on the amount of early cortical pre-damage.