Fracture risk in patients with newly diagnosed type 2 diabetes: a retrospective database analysis in primary care

Bone Fragility in Diabetes and its Management: A Narrative Review

Bone fragility is a serious yet under-recognised complication of diabetes mellitus (DM) that is associated with significant morbidity and mortality. Multiple complex pathophysiological mechanisms mediating bone fragility amongst DM patients have been proposed and identified. Fracture risk in both type 1 diabetes (T1D) and type 2 diabetes (T2D) continues to be understated and underestimated by conventional risk assessment tools, posing an additional challenge to the identification of at-risk patients who may benefit from earlier intervention or preventive strategies. Over the years, an increasing body of evidence has demonstrated the efficacy of osteo-pharmacological agents in managing skeletal fragility in DM. This review seeks to elaborate on the risk of bone fragility in DM, the underlying pathogenesis and skeletal alterations, the approach to fracture risk assessment in DM, management strategies and therapeutic options.

Lower microhardness along with less heterogeneous mineralization in the femoral neck of individuals with type 2 diabetes mellitus indicates higher fracture risk

There is still limited understanding of the microstructural reasons for the higher susceptibility to fractures in individuals with type 2 diabetes mellitus (T2DM). In this study, we examined bone mineralization, osteocyte lacunar parameters, and microhardness of the femoral neck trabeculae in 18 individuals with T2DM who sustained low-energy fracture (T2DMFx: 78 ± 7 years, 15 women and 3 men) and 20 controls (74 ± 7 years, 16 women and 4 men). Femoral necks of the T2DMFx subjects were obtained at a tertiary orthopedic hospital, while those of the controls were collected at autopsy. T2DMFx individuals had lower trabecular microhardness (P = .023) and mineralization heterogeneity (P = .001), and a tendency to a lower bone area with mineralization above 95th percentile (P = .058) than the controls. There were no significant intergroup differences in the numbers of osteocyte lacunae per bone area, mineralized lacunae per bone area, and total lacunae per bone area (each P > .05). After dividing the T2DMFx group based on the presence of vascular complications (VD) to T2DMFxVD (VD present) and T2DMFxNVD (VD absent), we observed that microhardness was particularly reduced in the T2DMFxVD group (vs. control group, P = .02), while mineralization heterogeneity was significantly reduced in both T2DMFx subgroups (T2DMFxNVD vs. control, P = .002; T2DMFxVD vs. control, P = .038). The observed changes in mineralization and microhardness may contribute to the increased hip fracture susceptibility in individuals with T2DM.

Exploration of the Shared Hub Genes and Biological Mechanism in Osteoporosis and Type 2 Diabetes Mellitus based on Machine Learning

A substantial amount of evidence suggests a close relationship between osteoporosis (OP) and Type 2 Diabetes Mellitus (T2DM), but the mechanisms involved remain unknown. Therefore, we conducted this study with the aim of screening for hub genes common to both diseases and conducting a preliminary exploration of common regulatory mechanisms. In the present study, we first screened genes significantly associated with OP and T2DM by the univariate logistic regression algorithm. And then, based on cross-analysis and random forest algorithm, we obtained three hub genes (ACAA2, GATAD2A, and VPS35) and validated the critical roles and predictive performance of the three genes in both diseases by differential expression analysis, receiver operating characteristic (ROC) curves, and genome wide association study (GWAS) analysis. Finally, based on gene set enrichment analysis (GSEA) and the construction of the miRNA-mRNA regulatory network, we conducted a preliminary exploration of the co-regulatory mechanisms of three hub genes in two diseases. In conclusion, this study provides promising biomarkers for predicting and treating both diseases and offers novel directions for exploring the common regulatory mechanisms of both diseases.

Underlying mechanisms and molecular targets of genistein in the management of type 2 diabetes mellitus and related complications

Diabetes mellitus (DM) is a chronic metabolic disease caused by a complex interaction of genetic and environmental factors and is characterized by persistent hyperglycemia. Long-term hyperglycemia can cause macrovascular and microvascular damage, and compromise the heart, brain, kidney, peripheral nerves, eyes and other organs, leading to serious complications. Genistein, a phytoestrogen derived from soybean, is known for its various biological activities and therapeutic properties. Recent studies found that genistein not only has hypoglycemic activity but can also decrease insulin resistance. In addition, genistein has particular activity in the prevention and treatment of diabetic complications, such as nephropathy, cardiovascular disease, osteoarthrosis, encephalopathy and retinopathy. Therefore, the purpose of this review is to summarize the latest medical research and progress of genistein in DM and related complications and highlights its potential molecular mechanisms and therapeutic targets. Meanwhile, evidence is provided for the development and application of genistein as a potential drug or functional food in the prevention and treatment of diabetes and its related complications.

Icariin promotes the proliferation and osteogenic differentiation of bone-derived mesenchymal stem cells in patients with osteoporosis and T2DM by upregulating GLI-1

BACKGROUND

The function of mesenchymal stem cells (MSCs) from patients with osteoporosis (OP) is impaired and worsens in patients with type 2 diabetes mellitus (T2DM). Icariin (ICA) is the major active flavonoid glucoside isolated from traditional Chinese herbal Epimedium pubescens, and confirmed able to improve bone mass of OP patients.

OBJECTIVE

To investigate the effect of ICA on the proliferation and osteogenic differentiation of bone-derived MSCs (BMSCs) from patients with OP and T2DM and uncover the potential mechanism.

METHODS

BMSCs were treated with ICA, and proliferation and osteogenic potency were evaluated using the 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and detection of osteogenic markers (ALP, RUNX2, SPP1, COL1A1, and mineralized nodules) was performed. RNA sequencing and bioinformatic analysis were performed to identify differentially expressed genes (DEGs) after ICA treatment and screen proliferation- and osteogenic differentiation-related processes. Gene gain and loss were performed to confirm the role of the key candidate gene.

RESULTS

ICA significantly promoted the proliferation and osteogenic differentiation of BMSCs. A total of 173 DEGs were identified after ICA treatment. Six DEGs (GLI-1, IGF2, BMP6, WNT5A, PTHLH, and MAPK14) enriched in both proliferation- and osteogenic differentiation-related processes were screened; GLI-1 had the highest validated |log2FC| value. Overexpression of GLI-1 enhanced the proliferation and osteogenic differentiation of BMSCs, and knockdown of GLI-1 weakened the positive effect of ICA on BMSCs.

CONCLUSION

ICA promoted the proliferation and osteogenic differentiation of impaired BMSCs by upregulating GLI-1.

Automatic severity grade classification of diabetic retinopathy using deformable ladder Bi attention U-net and deep adaptive CNN

Long-term exposure to diabetes mellitus leads to the formation of diabetic retinopathy (DR), which can cause vision loss in working-age adults. Early stage diagnosis of DR is highly essential for preventing vision loss and preserving vision in people with diabetes. The motivation behind the severity grade classification of DR is to develop an automated system that can assist ophthalmologists and healthcare professionals in the diagnosis and management of DR. However, existing methods suffer from variability in image quality, similar structures of the normal and lesion regions, high dimensional features, variability in disease manifestations, small datasets, high training loss, model complexity, and overfitting, which leads to high misclassification errors in the severity grading system. Hence, there is a need to develop an automated system using improved deep learning techniques to provide a reliable and consistent grading of DR severity with high classification accuracy using fundus images. To solve these issues, we proposes a Deformable Ladder Bi attention U-shaped encoder-decoder network and Deep Adaptive Convolutional Neural Network (DLBUnet-DACNN) for accurate severity classification of DR. The DLBUnet performs lesion segmentation that can be divided into three parts: the encoder, the central processing module and the decoder. In the encoder part, deformable convolution is used instead of convolution to learn different shapes of the lesion by understanding the offset location. Afterwards, Ladder Atrous Spatial Pyramidal Pooling (LASPP) using variable dilation rates is introduced in the central processing module. LASPP enhance the tiny lesion features and variable dilation rates avoid gridding effects and can learn better global context information. Then the decoder part uses a bi-attention layer contains spatial and channel attention, which can learn contour and edges of the lesion accurately. Finally, the severity of DR is classified using a DACNN by extracting the discriminative features from the segmentation results. Experiments are conducted on the Messidor-2, Kaggle, and Messidor datasets. Our proposed method DLBUnet-DACNN achieves better results in terms of accuracy of 98.2, recall of 0.987, kappa coefficient of 0.993, precision of 0.98, F1-score of 0.981, Matthews Correlation Coefficient (MCC) of 0.93 and Classification Success Index (CSI) of 0.96 when compared to existing methods.

Iron metabolism and ferroptosis in type 2 diabetes mellitus and complications: mechanisms and therapeutic opportunities

The maintenance of iron homeostasis is essential for proper endocrine function. A growing body of evidence suggests that iron imbalance is a key factor in the development of several endocrine diseases. Nowadays, ferroptosis, an iron-dependent form of regulated cell death, has become increasingly recognized as an important process to mediate the pathogenesis and progression of type 2 diabetes mellitus (T2DM). It has been shown that ferroptosis in pancreas β cells leads to decreased insulin secretion; and ferroptosis in the liver, fat, and muscle induces insulin resistance. Understanding the mechanisms concerning the regulation of iron metabolism and ferroptosis in T2DM may lead to improved disease management. In this review, we summarized the connection between the metabolic pathways and molecular mechanisms of iron metabolism and ferroptosis in T2DM. Additionally, we discuss the potential targets and pathways concerning ferroptosis in treating T2DM and analysis the current limitations and future directions concerning these novel T2DM treatment targets.

Vitamin D ameliorates insulin resistance-induced osteopenia by inactivating the nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome

Objective

Osteoporosis (OP) can be considered a chronic complication of type 2 diabetes mellitus (T2DM). Aberrant activation of the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is associated with the pathogenesis of various inflammation-related diseases, e.g., T2DM and OP. Vitamin D affects the inflammatory pathway and inhibits an excessive inflammatory response. The current study investigated the inter-relationship between vitamin D and inflammasome activation in T2DM.

Method

Hepatocellular carcinoma (HepG2) cells and bone marrow stromal cells (BMSCs) were treated with Conditioned Medium of bone marrow mesenchymal stem cells after VitD treatment (CM-VitD), as well as phosphoinositide 3-kinase (PI3K) specific agonist, 740Y-P, or the PI3K specific inhibitor, LY294002, respectively, or both. 40 Eight-week-old female Sprague Dawley rats were selected and established as a DM model. The rats were injected with CM-VitD, as well as the 740Y-P specific agonist, or the LY294002 inhibitor, respectively, or both. A quantitative reverse transcription polymerase chain reaction and western blotting were conducted to evaluate the expression of messenger ribonucleic acid and protein in the RUX2 gene, alkaline phosphatase (ALP), OsteoPontiN (OPN), peroxisome proliferator-activated receptor gamma (PPARγ), fatty acid-binding protein 4 (FABP4), protein kinase B (AKT), PI3K, NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1, interleukin (IL)-1 beta (β), IL-18, and tumor necrosis factor alpha (TNF-α) in the BMSCs and liver tissue of rats. Enzyme-linked immunosorbent assay was used to detect the concentration of inflammatory factors in the cell supernatant and serum of rats.

Results

An isolated co-culture of HepG2/insulin-resistance cells and BMSCs promoted the adipogenic transformation of the latter and inhibited the transformation of BMSCs into osteogenesis. The PI3K specific agonist, 740Y-P, significantly increased the expression of PI3K, AKT, NLRP3, ASC and Caspase-1 while the PI3K specific inhibitor, LY294002, does the opposite. Additionally, CM-VitD reduced the expression of NLRP3, ASC, caspase-1, IL-1β, and IL-18 in BMSCs and rat liver via the PI3K/AKT pathway.

Conclusion

Vitamin D can inhibit the inflammatory response induced by T2DM and promote the osteogenesis of BMSCs, which may play a key role in the treatment of type 2 diabetes patients with OP.

Risk of fracture in adults with type 2 diabetes in Sweden: A national cohort study

BACKGROUND

Type 2 diabetes mellitus (T2DM) is considered a risk factor for fracture but the evidence regarding the impact of T2DM on fracture risk is conflicting. The objective of the study was to determine if patients with T2DM have increased fracture risk and if T2DM-related risk factors could be identified.

METHODS AND FINDINGS

In this national cohort study in Sweden, we investigated the risk of fracture in 580,127 T2DM patients, identified through the national diabetes register including from both primary care and hospitals, and an equal number of population-based controls without diabetes matched for age, sex, and county from 2007 to 2017. The mean age at entry was 66.7 years and 43.6% were women. During a median follow-up time of 6.6 (interquartile range (IQR) 3.1 to 9.8) years, patients with T2DM had a marginally but significantly increased risk of major osteoporotic fracture (MOF) (hazard ratio (HR) 1.01 (95% confidence interval [CI] 1.00 to 1.03)) and hip fracture (HR 1.06 (95% CI 1.04 to 1.08)) compared to controls, associations that were only minimally affected (HR 1.05 (95% CI 1.03 to 1.06) and HR 1.11 (95% CI 1.09 to 1.14), respectively) by multivariable adjustment (age, sex, marital status, and an additional 20 variables related to general morbidity, cardiovascular status, risk of falls, and fracture). In a multivariable-adjusted Cox model, the proportion of the risk for all fracture outcomes (Heller's R2) explained by T2DM was below 0.1%. Among the T2DM patients, important risk factors for fracture were a low BMI (<25 kg/m2), long diabetes duration (≥15 years), insulin treatment, and low physical activity. In total, 55% of the T2DM patients had none of these risk factors and a significantly lower fracture risk than their respective controls. The relatively short mean duration of T2DM and lack of bone density data, constitute limitations of the analysis.

CONCLUSION

In this study, we observed only a marginally increased fracture risk in T2DM, a condition that explained less than 0.1% of the fracture risk. Consideration of the herein identified T2DM-related risk factors could be used to stratify T2DM patients according to fracture risk.

ATF3 Regulates Osteogenic Function by Mediating Osteoblast Ferroptosis in Type 2 Diabetic Osteoporosis

PURPOSE

Osteoporosis is a complication of type 2 diabetes, and it is characterized by reduced bone mass, augmented bone fragility, and increased risk of fracture, thus reducing patient quality of life, especially in the elderly. Ferroptosis has been implicated in the pathological process of type 2 diabetic osteoporosis (T2DOP), but the specific underlying mechanisms remain largely unknown. This study clarified the role of activating transcription factor 3 (ATF3) in T2DOP and explored its specific regulatory mechanism, providing a new treatment target for T2DOP.

METHODS

We cultured hFob1.19 cells in high glucose (HG, 35 mM) and knocked down ATF3 using short hairpin RNA (shRNA). We then measured cell viability, assessed morphology, quantified the expression of ATF3 and glutathione peroxidase 4 (GPX4), detected the levels of reactive oxygen species (ROS) and lipid peroxides, and determined the osteogenic function of osteoblasts. Cystine/glutamate antiporter (system Xc-) activity was evaluated by determining the expression of SLC7A11 and the levels of glutathione (GSH) and extracellular glutamate. We constructed a T2DOP rat model and observed the effect of ATF3 on ferroptosis and T2DOP by knocking down ATF3 using small interfering RNA (siRNA). Then, we evaluated the levels of iron metabolism, lipid peroxidation, and bone turnover in serum, detected the expression of ATF3, SLC7A11, and GPX4 in bone tissues, and assessed bone microstructure using microcomputed tomography.

RESULTS

ATF3 expression was increased in osteoblasts under HG condition and in T2DOP rats. Inhibiting the function of ATF3 increased GPX4 levels and reduced the accumulation of ROS and lipid peroxides. These changes inhibited the ferroptosis of osteoblasts and improved osteogenic function. In addition, HG induced ATF3 upregulation, resulting in decreased SLC7A11 expression and lower levels of intracellular GSH and extracellular glutamate.

CONCLUSION

Osteoblast ferroptosis under HG conditions is induced by ATF3-mediated inhibition of system Xc- activity, and these events contribute to T2DOP pathogenesis.

Diabetes and Impaired Fracture Healing: A Narrative Review of Recent Literature

PURPOSE OF THE REVIEW

Diabetes mellitus is a chronic metabolic disorder commonly encountered in orthopedic patients. Both type 1 and type 2 diabetes mellitus increase fracture risk and impair fracture healing. This review examines complex etiology of impaired fracture healing in diabetes.

RECENT FINDINGS

Recent findings point to several mechanisms leading to orthopedic complications in diabetes. Hyperglycemia and chronic inflammation lead to increased formation of advanced glycation end products and generation of reactive oxygen species, which in turn contribute to the disruption in osteoblast and osteoclast balance leading to decreased bone formation and heightening the risk of nonunion or delayed union as well as impaired fracture healing. The mechanisms attributing to this imbalance is secondary to an increase in pro-inflammatory mediators leading to premature resorption of callus cartilage and impaired bone formation due to compromised osteoblast differentiation and their apoptosis. Other mechanisms include disruption in the bone's microenvironment supporting different stages of healing process including hematoma and callus formation, and their resolution during bone remodeling phase. Complications of diabetes including peripheral neuropathy and peripheral vascular disease also contribute to the impairment of fracture healing. Certain diabetic drugs may have adverse effects on fracture healing. The pathophysiology of impaired fracture healing in diabetic patients is complex. This review provides an update of the most recent findings on how key mediators of bone healing are affected in diabetes.

A gene expression profile for the lower osteogenic potent of bone-derived MSCs from osteoporosis with T2DM and the potential mechanism

Background

Osteoporosis (OP) patients complicated with type II diabetes mellitus (T2DM) has a higher fracture risk than the non-diabetic patients, and mesenchymal stem cells (MSCs) from T2DM patients also show a weaker osteogenic potent. The present study aimed to provide a gene expression profile in MSCs from diabetic OP and investigated the potential mechanism.

Methods

The bone-derived MSC (BMSC) was isolated from OP patients complicated with or without T2DM (CON-BMSC, T2DM-BMSC). Osteogenic differentiation was evaluated by qPCR analysis of the expression levels of osteogenic markers, ALP activity and mineralization level. The differentially expressed genes (DEGs) in T2DM-BMSC was identified by RNA-sequence, and the biological roles of DEGs was annotated by bioinformatics analyses. The role of silencing the transcription factor (TF), Forkhead box Q1 (FOXQ1), on the osteogenic differentiation of BMSC was also investigated.

Results

T2DM-BMSC showed a significantly reduced osteogenic potent compare to the CON-BMSC. A total of 448 DEGs was screened in T2DM-BMSC, and bioinformatics analyses showed that many TFs and the target genes were enriched in various OP- and diabetes-related biological processes and pathways. FOXQ1 had the highest verified fold change (abs) among the top 8 TFs, and silence of FOXQ1 inhibited the osteogenic differentiation of CON-BMSC.

Conclusions

Our study provided a comprehensive gene expression profile of BMSC in diabetic OP, and found that downregulated FOXQ1 was responsible for the reduced osteogenic potent of T2DM-BSMC. This is of great importance for the special mechanism researches and the treatment of diabetic OP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03291-2.

Incidence and risk factors for early and late reoperation following lumbar fusion surgery

STUDY DESIGN

Retrospective cohort study.

PURPOSE

The aim of our study was to determine the rates and indications of reoperations following primary lumbar fusion, as well as the independent risk factors for early and late reoperation.

METHODS

We retrospectively reviewed patients who underwent lumbar fusion surgery between January 2017 and March 2020. All patients were followed up for more than 2 years. Characteristics, laboratory tests, primary diagnosis and surgery-related variables were compared among the early reoperation (< 3 months), the late reoperation (> 3 months) and the non-reoperation groups. Multivariable logistic regression analysis was used to identify independent risk factors for early and late reoperations.

RESULTS

Of 821 patients included in our studies, 34 patients underwent early reoperation, and 36 patients underwent late reoperation. The cumulative reoperation rate was about 4.1% (95% CI 3.8-4.5%) at 3 months, 6.2% (95% CI 5.9-6.5%) at 1 year and 8.2% (95% CI 8.0-8.5%) at 3 years. Multivariable analysis indicated that osteoporosis (odds ratio [OR] 3.6, 95% CI 1.2-10.5, p = 0.02) and diabetes (OR 2.1, 95% CI 1.1-4.5, p = 0.04) were independently associated with early reoperation and multilevel fusion (OR 2.4, 95% CI 1.1-5.4, p = 0.03) was independently associated with late reoperation.

CONCLUSIONS

The most common reasons for early reoperation and late operation were surgical site infection and adjacent segment diseases, respectively. Osteoporosis and diabetes were independent risk factors for early reoperation, and multilevel fusion was independent risk factor for late reoperation. Surgeons should pay more attention to these patients, and future studies should consider the effects of follow-up periods on results.

Evaluating the performance of the Charlson Comorbidity Index (CCI) in fracture risk prediction and developing a new Charlson Fracture Index (CFI): a register-based cohort study

The Charlson Comorbidity Index (CCI) may be applicable for predicting fracture risk since several diagnoses from the index are predictors of fracture. Main results were that the CCI was updated to predict risk of hip fracture with fair precision and that the index could be useful in detecting high-risk individuals.

PURPOSE

Several of the Charlson Comorbidity Index (CCI) diagnoses are validated predictors of fracture. The purpose of this study was to evaluate the performance of the CCI 1987 by Charlson et al. and of the CCI 2011 by Quan et al. in predicting major osteoporotic fracture (MOF) and hip fracture (HF). Furthermore, it was examined whether the index could be modified to improve fracture risk prediction.

METHODS

The study population included the entire Danish population aged 45 + years as per January 1, 2018. The cohort was split randomly 50/50 into a development and a validation cohort. CCI diagnoses and fracture outcomes were identified from hospital diagnoses. The weighting of diagnoses was updated in a new Charlson Fracture Index (CFI) using multivariable logistic regression. Predictive capabilities of the CCI 1987, the updated CCI 2011 and the new Charlson Fracture index were evaluated in the validation cohort by receiver operating characteristics (ROC) curves and area under the curve (AUC).

RESULTS

In the validation cohort, the 1987 and 2011 CCIs resulted in AUCs below or around 0.7 in prediction of MOF and HF in both sexes. The CFI resulted in AUCs < 0.7 in prediction of MOF in both sexes. In prediction of HF, the CFI resulted in AUC of 0.755 (95% CI 0.749; 0.761) in women and 0.782 (95% CI 0.772; 0.793) in men.

CONCLUSION

The 1987 and 2011 CCIs showed overall poor accuracy in fracture risk prediction. The CFI showed fair accuracy in prediction of HF in women and in men.

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.

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.

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.

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.

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.

Incident Type 2 Diabetes and Risk of Fracture: A Comparative Cohort Analysis Using U.K. Primary Care Records

OBJECTIVE

To estimate risk of fracture in men and women with recent diagnosis of type 2 diabetes compared with individuals without diabetes.

RESEARCH DESIGN AND METHODS

In this cohort study, we used routinely collected U.K. primary care data from The Health Improvement Network. In adults (>35 years) diagnosed with type 2 diabetes between 2004 and 2013, fractures sustained until 2019 were identified and compared with fractures sustained in individuals without diabetes. Multivariable models estimated time to first fracture following diagnosis of diabetes. Annual prevalence rates included at least one fracture in a given year.

RESULTS

Among 174,244 individuals with incident type 2 diabetes and 747,290 without diabetes, there was no increased risk of fracture among males with diabetes (adjusted hazard ratio [aHR] 0.97 [95% CI 0.94, 1.00]) and a small reduced risk among females (aHR 0.94 [95% CI 0.92, 0.96]). In those aged ≥85 years, those in the diabetes cohort were at significantly lower risk of incident fracture (males: aHR 0.85 [95% CI 0.71, 1.00]; females: aHR 0.85 [95% CI 0.78, 0.94]). For those in the most deprived areas, aHRs were 0.90 (95% CI 0.83, 0.98) for males and 0.91 (95% CI 0.85, 0.97) for females. Annual fracture prevalence rates, by sex, were similar for those with and without type 2 diabetes.

CONCLUSIONS

We found no evidence to suggest a higher risk of fracture following diagnosis of type 2 diabetes. After a diagnosis of type 2 diabetes, individuals should be encouraged to make positive lifestyle changes, including undertaking weight-bearing physical activities that improve bone health.

Correlation of Osteoporosis in Patients With Newly Diagnosed Type 2 Diabetes: A Retrospective Study in Chinese Population

This study aimed to explore the risk factors attributed to osteoporosis in newly type 2 diabetes mellitus (T2DM) patients. This study aimed to recruit 244 T2DM patients and 218 non-diabetic controls. We collected demographic characteristics, medical history, bone mineral density and biomarkers including bone specific alkaline phosphatase (BALP), osteocalcin, N-terminal peptide of type I procollagen (P1NP), tartrate-resistant acid phosphatase 5b (TRCAP-5b), β-Cross Laps of type I collagen-containing cross-linked C-telopeptide (β-CTX), 25-hydroxyvitamin D, parathyroid hormone were recorded or detected. Bone mineral density (BMD) was our primary outcome. Based on the result of BMD, we divided both the control group and T2DM group into three subgroups: normal bone mass, osteopenia and osteoporosis. In control group, we found age, sex, menopausal status, BMI, P1NP, BALP, TRACP-5b, osteocalcin, and corrected serum calcium are differential among three subgroups. In T2DM group, we found age, sex, menopausal status, drinking status, BMI, HbA1c, TRACP-5b and OC were differential among three subgroups. In T2DM and control groups, age, female, postmenopausal status, BALP, TRACP-5b and osteocalcin were positively correlated while BMI was negatively correlated with osteoporosis. In control group, β-CTX was positively correlated with osteoporosis. In T2DM group, HbA1c and corrected serum calcium concentration were positively correlated with osteoporosis. After further adjustment of age, BMI in male, TRACP-5b was positively correlated with the risk of osteoporosis in newly diagnosed T2DM. After adjusted of age, BMI and menopausal status in female, OC was positively correlated with the risk of osteoporosis in newly diagnosed T2DM and controls. In female T2DM, BALP and P1NP were positively correlated with the risk of osteoporosis. In conclusion, age, BMI and menopausal status are common risk factors for osteoporosis in diabetic and non-diabetic patients, however TRACP-5b, BALP and osteocalcin are special risk factors for osteoporosis in newly diagnosed T2DM patients but not non-diabetic patients, which may be applied to identify osteoporosis risk in T2DM patients, but this result needs to be proven with fracture data.

Melatonin Suppresses Ferroptosis Induced by High Glucose via Activation of the Nrf2/HO-1 Signaling Pathway in Type 2 Diabetic Osteoporosis

Ferroptosis is recently identified, an iron- and reactive oxygen species- (ROS-) dependent form of regulated cell death. This study was designed to determine the existence of ferroptosis in the pathogenesis of type 2 diabetic osteoporosis and confirm that melatonin can inhibit the ferroptosis of osteoblasts through activating Nrf2/HO-1 signaling pathway to improve bone microstructure in vivo and in vitro. We treated MC3T3-E1 cells with different concentrations of melatonin (1, 10, or 100 μM) and exposed them to high glucose (25.5 mM) for 48 h in vitro. Our data showed that high glucose can induce osteoblast cytotoxicity and the accumulation of lipid peroxide, the mitochondria of osteoblast show the same morphology changes as the erastin treatment group, and the expression of ferroptosis-related proteins glutathione peroxidase 4 (GPX4) and cystine-glutamate antiporter (SLC7A11) is downregulated, but these effects were reversed by ferroptosis inhibitor ferrastatin-1 and iron chelator deferoxamine (DFO). Furthermore, western blot and real-time polymerase chain reaction were used to detect the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1); osteogenic capacity was evaluated by alizarin red S staining and the expression of osteoprotegerin, osteocalcin, and alkaline phosphatase; the results showed that the expression levels of these proteins in osteoblasts with 1, 10, or 100 μM melatonins were significantly higher than the high glucose group, but after using Nrf2-SiRNA interference, the therapeutic effect of melatonin was significantly inhibited. We also performed in vivo experiments in a diabetic rat model treated with two concentrations of melatonin (10, 50 mg/kg). Dynamic bone histomorphometry and micro-CT were used to observe the rat bone microstructure, and the expression of GPX4 and Nrf2 was determined by immunohistochemistry. Here, we first report that high glucose induces ferroptosis via increased ROS/lipid peroxidation/glutathione depletion in type 2 diabetic osteoporosis. More importantly, melatonin significantly reduced the level of ferroptosis and improved the osteogenic capacity of MC3T3-E1 through activating the Nrf2/HO-1 pathway in vivo and in vitro.

Risk of amputation with canagliflozin across categories of age and cardiovascular risk in three US nationwide databases: cohort study

OBJECTIVE

To estimate the rate of lower limb amputation among adults newly prescribed canagliflozin according to age and cardiovascular disease.

DESIGN

Population based, new user, cohort study.

DATA SOURCES

Two commercial and Medicare claims databases, 2013-17.

PARTICIPANTS

Patients newly prescribed canagliflozin were propensity score matched 1:1 with patients newly prescribed a glucagon-like peptide-1 (GLP-1) receptor agonist. Hazard ratios and rate differences per 1000 person years were computed for the rate of lower limb amputation in the following four groups: group 1, patients aged less than 65 years without baseline cardiovascular disease; group 2, patients aged less than 65 with baseline cardiovascular disease; group 3, patients aged 65 or older without baseline cardiovascular disease; group 4, patients aged 65 or older with baseline cardiovascular disease. Within each group, pooled hazard ratio and rate difference per 1000 person years were calculated by meta-analysis.

INTERVENTION

Canagliflozin versus a GLP-1 agonist.

MAIN OUTCOME MEASURES

Lower limb amputation requiring surgery.

RESULTS

Across the three databases, 310 840 propensity score matched adults who started canagliflozin or a GLP-1 agonist were identified. The hazard ratio and rate difference per 1000 person years for amputation in adults receiving canagliflozin compared with a GLP-1 agonist for each group was: group 1, hazard ratio 1.09 (95% confidence interval 0.83 to 1.43), rate difference 0.12 (-0.31 to 0.55); group 2, hazard ratio 1.18 (0.86 to 1.62), rate difference 1.06 (-1.77 to 3.89); group 3, hazard ratio 1.30 (0.52 to 3.26), rate difference 0.47 (-0.73 to 1.67); and group 4, hazard ratio 1.73 (1.30 to 2.29), rate difference 3.66 (1.74 to 5.59).

CONCLUSIONS

The increase in rate of amputation with canagliflozin was small and most apparent on an absolute scale for adults aged 65 or older with baseline cardiovascular disease, resulting in a number needed to treat for an additional harmful outcome of 556 patients at six months (that is, 18 more amputations per 10 000 people who received canagliflozin). These results help to contextualize the risk of amputation with canagliflozin in routine care.

The risk of hip and non-vertebral fractures in type 1 and type 2 diabetes: A systematic review and meta-analysis update

BACKGROUND

Diabetes is associated with increased fracture risk but we do not know what affects this risk. We investigated the risk of hip and non-vertebral fractures in diabetes and whether this risk was affected by age, gender, body mass index, diabetes type and duration, insulin use and diabetic complications.

METHODS

We selected a previously published review to be updated. MEDLINE, Embase and Cochrane databases were searched up to March 2020. We included observational studies with age and gender-adjusted risk of fractures in adults with diabetes compared to adults without diabetes. We extracted data from published reports that we summarised using random effects model.

FINDINGS

From the 3140 records identified, 49 were included, 42 in the hip fracture analysis, reporting data from 17,571,738 participants with 319,652 fractures and 17 in the non-vertebral fracture review, reporting data from 2,978,487 participants with 181,228 fractures. We found an increase in the risk of fracture in diabetes both for hip (RR 4.93, 3.06-7.95, in type 1 diabetes and RR1.33, 1.19-1.49, in type 2 diabetes) and for non-vertebral fractures (RR 1.92, 0.92-3.99, in type 1 and RR 1.19, 1,11-1.28 in type 2). At the hip, the risk was higher in the younger population in both type 1 and type 2 diabetes. In those with type 2 diabetes, longer diabetes duration and insulin use was associated with an increased risk. We did not investigate the effect of bone density, falls, anti-diabetic drugs and hypoglycemia.

CONCLUSION

Diabetes is associated with an increase in both hip and non-vertebral fracture risk.

Incidence of fractures in patients with type 1 diabetes mellitus-a retrospective study with 4420 patients

This retrospective study investigated the incidence of fracture in 4420 type 1 diabetes (T1DM) patients. Our findings indicate that patients with T1DM have an increased incidence of fractures. Further studies and preventive measures are urgently needed.

INTRODUCTION

The aim of this study was to investigate the incidence of fracture in patients with type 1 diabetes mellitus (T1DM).

METHODS

This study is based on the German Disease Analyzer database and included 4258 adult individuals with a T1DM diagnosis documented between January 2000 and December 2015 in 1203 general practices in Germany. Individual matching of T1DM and non-diabetic patients was performed. The cumulative incidence of new fractures was shown for up to 10 years after the index date using Kaplan-Meier curves. Cox proportional hazard models (dependent variable: incident fracture) were used to estimate the effect of T1DM on fracture incidence, as well as the effect of predefined variables on fracture incidence.

RESULTS

After 10 years of follow-up, the cumulative fracture incidence was 18.4% for T1DM patients and 9.9% for non-diabetic patients (p < 0.001). A strong association between T1DM and fractures was found (HR, 2.01 (95% CI, 1.70-2.38) p < 0.001) in both female and male patients. Significant differences between T1DM and non-diabetes patients were found in lower leg/ankle, foot and toe, shoulder/upper arm, and rib(s), sternum and thoracic spine fractures. A significant association between higher age and fracture incidence was observed in T1DM patients.

CONCLUSIONS

In summary, we found that patients with T1DM have a twofold increased fracture rate compared with healthy controls. Furthermore, fractures were associated with increased age and high HbA1c values.

The Impact of Roux-en-Y Gastric Bypass on Bone Remodeling Expressed by the P1NP/βCTX Ratio: a Single-Center Prospective Cohort Study

BACKGROUND

Bariatric surgery seems to decrease bone mineral density and increase the risk of fatigue fractures. P1NP (bone formation) and βCTX (bone resorption) were recently validated as reference bone turnover markers (BTM).

OBJECTIVE

To assess changes in bone remodeling in severely obese patients undergoing Roux-en-Y gastric bypass (RYGB) by using a new composite biomarker, the P1NP/βCTX ratio.

METHODS

We prospectively collected blood samples preoperatively, at 1 month and at 1 year from 114 consecutive RYGB patients from 12/2012 to 04/2014. Repeated measures ANOVA and multiple regression were used for data analysis. Cumulative incidence of fractures was assessed in 06/2018.

RESULTS

The P1NP/βCTX ratio decreased significantly (P < 0.001) from baseline to 1 month and 1 year (180 ± 6.6, 110 ± 4.1, and 132 ± 5.4). The 1-year P1NP/βCTX ratio did not correlate with BMI or ΔBMI, but inversely correlated with age (r = - 0.23, P = 0.014) and with hsCRP (r = - 0.26, P = 0.009), even after adjustment for age, sex, BMI, and lifestyle, and linearly correlated with albumin (r = 0.2, P = 0.037). At baseline, none of these correlations were detectable. Serum for all time-points was available from > 94% of the patients. At a median follow-up of 4.7 years, 8 patients (7.3%) had a bone fracture, all of them traumatic.

CONCLUSION

Following RYGB, bone remodeling increases, with a shift toward degradation. This effect seems to be weight-loss independent and shows a correlation with age, with the level of systemic inflammation, and with nutritional state. The risk of fractures should be assessed systematically in bariatric patients and measures of prevention should be improved accordingly.

Vertebral Fractures in Individuals With Type 2 Diabetes: More Than Skeletal Complications Alone

OBJECTIVE

We aimed to assess whether individuals with type 2 diabetes (T2D) have increased risk of vertebral fractures (VFs) and to estimate nonvertebral fracture and mortality risk among individuals with both prevalent T2D and VFs.

RESEARCH DESIGN AND METHODS

A systematic PubMed search was performed to identify studies that investigated the relationship between T2D and VFs. Cohorts providing individual participant data (IPD) were also included. Estimates from published summary data and IPD cohorts were pooled in a random-effects meta-analysis. Multivariate Cox regression models were used to estimate nonvertebral fracture and mortality risk among individuals with T2D and VFs.

RESULTS

Across 15 studies comprising 852,705 men and women, individuals with T2D had lower risk of prevalent (odds ratio [OR] 0.84 [95% CI 0.74-0.95]; I ² = 0.0%; P _het = 0.54) but increased risk of incident VFs (OR 1.35 [95% CI 1.27-1.44]; I ² = 0.6%; P _het = 0.43). In the IPD cohorts (N = 19,820), risk of nonvertebral fractures was higher in those with both T2D and VFs compared with those without T2D or VFs (hazard ratio [HR] 2.42 [95% CI 1.86-3.15]) or with VFs (HR 1.73 [95% CI 1.32-2.27]) or T2D (HR 1.94 [95% CI 1.46-2.59]) alone. Individuals with both T2D and VFs had increased mortality compared with individuals without T2D and VFs (HR 2.11 [95% CI 1.72-2.59]) or with VFs alone (HR 1.84 [95% CI 1.49-2.28]) and borderline increased compared with individuals with T2D alone (HR 1.23 [95% CI 0.99-1.52]).

CONCLUSIONS

Based on our findings, individuals with T2D should be systematically assessed for presence of VFs, and, as in individuals without T2D, their presence constitutes an indication to start osteoporosis treatment for the prevention of future fractures.

Fracture Risk After Initiation of Use of Canagliflozin: A Cohort Study

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors promote glycosuria, resulting in possible effects on calcium, phosphate, and vitamin D homeostasis. Canagliflozin is associated with decreased bone mineral density and a potential increased risk for fracture.

OBJECTIVE

To estimate risk for nonvertebral fracture among new users of canagliflozin compared with a glucagon-like peptide-1 (GLP-1) agonist.

DESIGN

Population-based new-user cohort study.

SETTING

Two U.S. commercial health care databases providing data on more than 70 million patients from March 2013 to October 2015.

PATIENTS

Persons with type 2 diabetes who initiated use of canagliflozin were propensity score-matched in a 1:1 ratio to those initiating use of a GLP-1 agonist.

MEASUREMENTS

The primary outcome was a composite end point of humerus, forearm, pelvis, or hip fracture requiring intervention. Secondary outcomes included fractures at other sites. A fixed-effects meta-analysis that pooled results from the 2 databases provided an overall hazard ratio (HR).

RESULTS

79 964 patients initiating use of canagliflozin were identified and matched to 79 964 patients initiating use of a GLP-1 agonist. Mean age was 55 years, 48% were female, average baseline hemoglobin A1c level was 8.7%, and 27% were prescribed insulin. The rate of the primary outcome was similar for canagliflozin (2.2 events per 1000 person-years) and GLP-1 agonists (2.3 events per 1000 person-years), with an overall HR of 0.98 (95% CI, 0.75 to 1.26). Risk for pelvic, hip, humerus, radius, ulna, carpal, metacarpal, metatarsal, or ankle fracture was also similar for canagliflozin (14.5 events per 1000 person-years) and GLP-1 agonists (16.1 events per 1000 person-years) (overall HR, 0.92 [CI, 0.83 to 1.02]).

LIMITATION

Unmeasured confounding, measurement error, and low fracture rate.

CONCLUSION

In this study of middle-aged patients with type 2 diabetes and relatively low fracture risk, canagliflozin was not associated with increased risk for fracture compared with GLP-1 agonists.

PRIMARY FUNDING SOURCE

Brigham and Women's Hospital, Division of Pharmacoepidemiology and Pharmacoeconomics.

OSTEOPOROSIS AND FRACTURE RISK IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

Type 2 diabetes mellitus (T2DM) is associated with an increased risk of fragility fractures compared to the general population. The pathogenesis of the elevated fracture risk is multifactorial and still largely elusive. In contrast to primary osteoporosis, in T2DM the bone mineral density (BMD) is increased compared to controls, suggesting that specific alterations in bone quality occur in diabetic patients. Even more, the specific increase in BMD observed in these patients impairs at least in part both the classical diagnosis of osteoporosis by dual-energy X-ray absorptiometry (DXA) and the current fracture risk estimation by FRAX (fracture risk assessment tool). Trabecular bone score (TBS) and TBS-adjusted FRAX could improve fracture risk estimation in patients with T2DM but improved tools are needed in the future as well as specific risk stratification criteria. Decreases in the fracture risk of patients with T2DM can be obtained by optimal diabetes control and standard treatment of osteoporosis (most drugs appear to have similar efficacy in patients with T2DM and primary osteoporosis).

Alterations of Bone Metabolism in Patients with Diabetes Mellitus

AIM

The study aims to develop a practical model for screening bone turnover state in patients with diabetes and evaluate its clinical usefulness to identify diabetic osteopathy.

MATERIALS

The study was conducted in 2015-2017 in the Endocrinology Department of the Therapeutic Clinic of AM University. A total of 235 patients were assessed in the study (98 with T1DM and 137 with T2DM). 89 nondiabetic subjects served as controls. Bone mineral density (BMD) [by dual energy X-ray absorptiometry (DXA)] and serum markers of bone remodeling [aminoterminal propeptide of procollagen type I (P1NP) and c-terminal telopeptide of type I collagen (CTX)], parathyrin, and 25(OH)D were measured in all 235 patients.

RESULTS

Our results show that patients with T2DM have lower b-CTx values and relatively higher levels of P1NP, reflecting less pronounced changes in bone metabolism compared to patients with T1DM, regardless of age or duration of the disease. Osteoporosis was detected in 50% of patients with T1DM, compared to 13% of patients with T2DM.

CONCLUSION

In some cases, bone remodeling markers are useful for improving the assessment of the state of bone tissue in early stages of diabetes, while alterations in bone microarchitecture may not always be captured by bone mineral density measurements.

Risk of hip fractures in patients with depressive disorders: A nationwide, population-based, retrospective, cohort study

Background

Some studies have suggested that depressive disorders may play a vital role in the incidence of hip fractures. However, nationwide data are lacking regarding the association between depressive disorders and hip fractures.

Objective

We aimed to explore the association between depressive disorders and new-onset hip fractures.

Methods

We conducted a retrospective study of 11,207 patients with depressive disorders and 11,207 control patients using Taiwan’s National Health Insurance Research Database. A Cox regression model was used to evaluate the risk of hip fractures in patients with depressive disorders.

Results

The incidence rate ratio of hip fractures between patients with depressive disorders and controls was 1.6 (95% confidence interval [CI] = 1.29–1.99, P < .001). After adjustment for potential confounders in multivariate analysis using the Cox regression model, patients with depressive disorders were found to have 1.34 times higher risk of hip fractures than controls (95% CI = 1.08–1.66, P = .008). Furthermore, age (hazard ratio [HR] = 7.43, 95% CI = 4.94–11.19, P < .001), hypertension (HR = 1.63, 95% CI = 1.17–2.28, P = .004), diabetes mellitus (HR = 1.47, 95% CI = 1.08–1.99, P = .014), cerebrovascular disease (HR = 1.76, 95% CI = 1.31–2.35, P < .001), living in rural areas (HR = 1.88, 95% CI = 1.30–2.70, P = .001), and low monthly income (NT$0–NT$19,000: HR = 4.08, 95% CI = 1.79–9.29, P = .001 and NT$19,100–NT$42,000: HR = 4.09, 95% CI = 1.76–9.49, P = .001) were independent risk factors for new-onset hip fractures in patients with depressive disorders.

Conclusion

Depressive disorders might increase the risk of new-onset hip fractures, particularly in older patients and patients with hypertension, diabetes mellitus, cerebrovascular disease, or low socioeconomic status.

Fracture risk in women with type II diabetes. Results from a historical cohort with fracture follow-up

PURPOSE

To examine the independent association between type II diabetes and fracture risk in a population of predominantly postmenopausal women referred to a specialist clinic for osteoporosis evaluation.

METHODS

Type II diabetes associated fracture risk were evaluated among to 229 patients with type II diabetes in a cohort of 6285 women followed on average (until major osteoporotic fracture (MOF), death or end of study) for 5.8 years. Information of fracture risk factors was obtained from a clinical database and from national registries.

RESULTS

An elevated fracture risk was present. Prevalent fractures (43.7 vs. 33.2%, p = 0.0010) and prevalent MOF (26.2 vs. 20.5% p = 0.038) were more common among patients with type II diabetes. The unadjusted incident fracture risk was increased with a higher relative risk of 42%. An elevated MOF hazard ratio was present (HR = 1.726, p = 0.0006). Adjustment for prevalent osteoporosis and other possible confounders did not change this finding (HR = 1.558, p = 0.0207).

CONCLUSIONS

An association between type II diabetes and an increased risk of MOF primarily driven by an increased hip fracture risk was documented. This finding was independent of the presence of osteoporosis. Clinicians need to be aware of and adjust for these findings when evaluating patients with diabetes. Additional research examining pathophysiological mechanisms are needed.

Vertebral fractures assessed with dual-energy X-ray absorptiometry in patients with Addison's disease on glucocorticoid and mineralocorticoid replacement therapy

PURPOSE

to assess bone damage and metabolic abnormalities in patients with Addison's disease given replacement doses of glucocorticoids and mineralocorticoids.

METHODS

A total of 87 patients and 81 age-matched and sex-matched healthy controls were studied. The following parameters were measured: urinary cortisol, serum calcium, phosphorus, creatinine, 24-h urinary calcium excretion, bone alkaline phosphatase, parathyroid hormone, serum CrossLaps, 25 hydroxyvitamin D, and 1,25 dihydroxyvitamin D. Clear vertebral images were obtained with dual-energy X-ray absorptiometry in 61 Addison's disease patients and 47 controls and assessed using Genant's classification.

RESULTS

Nineteen Addison's disease patients (31.1%) had at least one morphometric vertebral fracture, as opposed to six controls (12.8%, odds ratio 3.09, 95% confidence interval 1.12-8.52). There were no significant differences in bone mineral density parameters at any site between patients and controls. In Addison's disease patients, there was a positive correlation between urinary cortisol and urinary calcium excretion. Patients with fractures had a longer history of disease than those without fractures. Patients taking fludrocortisone had a higher bone mineral density than untreated patients at all sites except the lumbar spine.

CONCLUSIONS

Addison's disease patients have more fragile bones irrespective of any decrease in bone mineral density. Supra-physiological doses of glucocorticoids and longer-standing disease (with a consequently higher glucocorticoid intake) might be the main causes behind patients' increased bone fragility. Associated mineralocorticoid treatment seems to have a protective effect on bone mineral density.

Prescription Patterns and Disease Control in Type 2 Diabetes Mellitus Patients in Nursing Home and Home Care Settings: A Retrospective Analysis in Germany

AIM

The aim of this study was to analyze prescription patterns and disease control in patients with type 2 diabetes mellitus (T2DM) in nursing home and home care settings in Germany.

METHODS

The present study is based on data from the Disease Analyzer database (QuintilesIMS). Patients with an initial diagnosis of T2DM and documented HbA1c values between January 2011 and December 2015 were included in the analysis. The index date corresponded to the last documented HbA1c value. Patients in nursing homes were matched (1:1) with patients living at home based on age, gender, and dementia diagnosis. The first outcome of the study was the share of use of several antidiabetic drugs in the two different settings. The second outcome was the mean HbA1c value and the proportion of patients with HbA1c values lower than 7% in the two different groups.

RESULTS

In this study, 4925 individuals lived in nursing homes and 4925 individuals lived at home. The mean age was 80.7 years (SD = 7.7). Prescription patterns differed significantly between nursing home and home care settings: insulin (57.9% vs 41.1%), metformin (46.6% vs 60.5%), sulfonylurea (24.9% vs 34.2%), DPP4 inhibitors (13.4% vs 19.8%), and other antihyperglycemic drugs (7.8% vs 12.1%). In contrast, mean HbA1c values (nursing home: 7.2%; home: 7.2%) and the share of patients with Hb1Ac values lower than 7% (nursing home: 49.1%; home: 50.9%) did not differ significantly between the two groups.

CONCLUSION

Overall, the differences in prescription patterns between nursing homes and home care were not associated with significant differences in the management of T2DM.

Oral contraceptive use and fracture risk-a retrospective study of 12,970 women in the UK

In the present retrospective case-control study, we compared 6485 women with fractures and 6485 women without fractures from 135 general practitioner offices in the UK. Women without bone fractures were statistically more likely to have been exposed to oral contraception, depending on their age and therapy duration.

INTRODUCTION

The aim of this analysis was to compare the risk of bone fracture in women using hormonal contraception with that in women who have never used hormonal contraception.

METHODS

A total of 6485 women (mean age 37.8 years) with an initial diagnosis of fracture between January 2010 and December 2015 were identified in 135 doctors' offices in the UK Disease Analyzer database. In this nested case-control study, each case with a fracture was matched (1:1) to a control without a fracture for age, index year, and follow-up time. In total, 12,970 individuals were available for analysis. The main outcome of the study was the risk of fracture as a function of combined oral contraceptive (OC) therapy. Multivariate logistic regression models were used to determine the effect of OC therapy and its duration on the risk of fracture in the entire population and in four age-specific subgroups.

RESULTS

Women without bone fractures were significantly more likely to have used oral contraception (OR 0.81). The usage of oral contraception was associated with a significantly lower risk of bone fracture (OR 0.81, 95% CI 0.74-0.90). This effect was strongest in the age groups 18-25 and 26-35 and in patients with an OC treatment duration of more than 1 year.

CONCLUSIONS

The present study revealed that women without bone fractures were significantly more likely to have had exposure to combined oral contraception, especially where the duration of intake was at least 5 years.

Use of dipeptidyl peptidase-4 inhibitors and risk of bone fracture in patients with type 2 diabetes in Germany-A retrospective analysis of real-world data

In type 2 diabetes patients treated in German primary care practices, the use of dipeptidyl peptidase-4 inhibitor (DPP4i) in combination with metformin was associated with a significant decrease in the risk of developing bone fractures compared to metformin monotherapy.

INTRODUCTION

The goal of this study was to analyze the impact of dipeptidyl peptidase-4 inhibitor (DPP4i) use on the risk of bone fracture in patients diagnosed with type 2 diabetes mellitus (T2DM) in Germany.

METHODS

Patients with an initial prescription of metformin between 2008 and 2014 from 1262 German general practitioner practices were selected. We matched 4160 DPP4i ever users to never users (1:1) based on age, sex, diabetes duration, body mass index, index year, and physician type. The primary outcome measure was the rate of bone fractures within five years of the start of metformin or DPP-4i therapy. Time-dependent Cox regression models were used to estimate hazard ratios (HRs) for fractures as a function of the DPP4i therapy.

RESULTS

The mean age among the patients was 61.6 years (SD = 11.1 years), 59.6% were men, and 3.1% were followed in diabetologist practices. The mean diabetes duration was 1.5 years (SD = 2.4 years), HbA1c levels were 7.1% in DPP4i users and 6.6% in non-users, and body mass index was 31.5 kg/m² (SD = 5.0 kg/m²). Within five years of the index date, 6.4% of users and 8.3% of non-users developed bone fractures (log-rank p-value < 0.001). Within five years of the index date, 7.4% of female and 4.7% of male users and 13.3% of female and 8.8% of male non-users were diagnosed with bone fractures (both log-rank p-values < 0.001). The use of DPP4i was associated with a significant decrease in the risk of developing bone fractures (all patients HR = 0.67, 95% CI 0.54-0.84; women HR = 0.72, 95% CI 0.54-0.97; men HR = 0.62, 95% CI 0.44-0.88).

CONCLUSION

DPP4i use was associated with a decrease in the risk of bone fracture.

Fracture Risk Assessment in Patients With Diabetes Mellitus

Diabetes mellitus, both type 1 and type 2 (T2DM), is associated with decreased bone strength as well as increased fracture risk. Bone mineral density is decreased in type 1 diabetes but increased in T2DM, compared with controls. This suggests alterations in bone quality are a major player in the pathogenesis of fragility fractures in patients with diabetes. The link between diabetes and bone appears to be mediated by complex pathways, including the insulin-insulin growth factors system, accumulation of advanced glycation end-products in bone collagen, microangiopathy, and increased bone marrow fat content. Bone fragility in T2DM, which is not reflected by bone mineral density and bone mass reduction, depends on deterioration of bone quality. Also, at least in T2DM, the classical diagnosis of osteoporosis by dual-energy X-ray absorptiometry and the fracture risk estimation by FRAX (fracture risk assessment tool) are only partially useful in assessing fracture risk. Trabecular bone score and trabecular bone score-adjusted FRAX offer an enhanced estimation of fracture risk in these patients. Specific risk stratification criteria are needed in the future. The development of improved methods to assess the material properties of bone to better characterize fracture risk is also a priority. Adequate glycemic control is generally associated with decreased fracture risk, with the exception of specific antidiabetics (thiazolidinediones, canagliflozin) that have been shown to have a detrimental effect. Most currently used antiosteoporotic treatments seem equally effective in diabetic patients as compared with patients without diabetes, but clinical data regarding the reduction in fracture risk specifically in patients with diabetes mellitus are lacking.

Pharmacological efficacy of FGF21 analogue, liraglutide and insulin glargine in treatment of type 2 diabetes

Fibroblast growth factor 21 (FGF21) is a promising regulator of glucose and lipid metabolism with multiple beneficial effects including hypoglycemic and lipid-lowering. Previous studies have reported that FGF21 is expected to become a new drug for treatment of diabetes. Liraglutide and insulin glargine are the two representative anti-diabetic biological drugs. In the current study, we aim to compare the long-term pharmacological efficacy of mFGF21 (an FGF21 analogue), liraglutide and insulin glargine in type 2 diabetic db/db mice. Db/db mice were initially treated with three kinds of proteins (25nmol/kg/day) by subcutaneous injection once a day for 4weeks, then subsequently be treated with once every two days for next 4weeks. After 8weeks of treatments, the blood glucose levels, body weights, glycosylated hemoglobin levels, fasting insulin levels, serum lipid profiles, hepatic biochemical parameters, oral glucose tolerance tests and hepatic mRNA expression levels of several proteins (GK, G6P, GLUT-1 and GLUT-4) associated with glucose metabolism of the experimental mice were detected. Results demonstrated that three proteins could significantly decrease the fed blood glucose levels of db/db mice. After treatment for 1week, the fed blood glucose levels of db/db mice in liraglutide group were significantly lower than those in mFGF21 and insulin glargine groups. However, after 2weeks of administration, the long-lasting hypoglycemic effect of mFGF21 was superior to liraglutide and insulin glargine up to the end of the experiments. Compared with liraglutide and insulin glargine, mFGF21 significantly reduced the glycosylated hemoglobin levels and improved the ability on glycemic control, insulin resistance, serum lipid and liver function states in db/db mice after 8weeks treatments. In addition, mFGF21 regulated glucose metabolism through increasing the mRNA expression levels of GK and GLUT-1, and decreasing the mRNA expression level of G6P. But liraglutide and insulin glargine could only up-regulate the mRNA expression of GLUT-4. In summary, as a hypoglycemic drug for long-term treatment, mFGF21 has the potential to be an ideal drug candidate for the therapy of type 2 diabetes.

Lack of evidence for a harmful effect of sodium-glucose co-transporter 2 (SGLT2) inhibitors on fracture risk among type 2 diabetes patients: a network and cumulative meta-analysis of randomized controlled trials

AIM

To evaluate the comparative effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on risk of bone fracture in patients with type 2 diabetes mellitus (T2DM).

METHODS

PubMed, EMBASE, CENTRAL and ClinicalTrials.gov were systematically searched from inception to 27 January 2016 to identify randomized controlled trials (RCTs) reporting the outcome of fracture in patients with T2DM treated with SGLT2 inhibitors. Pairwise and network meta-analyses, as well as a cumulative meta-analysis, were performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

A total of 38 eligible RCTs (10 canagliflozin, 15 dapagliflozin and 13 empagliflozin) involving 30 384 patients, with follow-ups ranging from 24 to 160 weeks, were included. The fracture event rates were 1.59% in the SGLT2 inhibitor groups and 1.56% in the control groups. The incidence of fracture events was similar among these three SGLT2 inhibitor groups. Compared with placebo, canagliflozin (OR 1.15; 95% CI 0.71-1.88), dapagliflozin (OR 0.68; 95% CI 0.37-1.25) and empagliflozin (OR 0.93; 95% CI 0.74-1.18) were not significantly associated with an increased risk of fracture. Our cumulative meta-analysis indicated the robustness of the null findings with regard to SGLT2 inhibitors.

CONCLUSIONS

Our meta-analysis based on available RCT data does not support the harmful effect of SGLT2 inhibitors on fractures, although future safety monitoring from RCTs and real-world data with detailed information on bone health is warranted.

Bone mineral density and intervertebral disc height in type 2 diabetes

BACKGROUND

Studies of the effect of type 2 diabetes (T2D) on bone mineral density (BMD have produced conflicting results, possibly due to failure to adjust for potential confounding factors. Nonetheless, T2D has consistently been associated with increased fracture risk, suggesting that other factors might play a role.

OBJECTIVE

This study assesses the relationship between T2D and BMD at the femoral neck and spine in diabetic and non-diabetic subjects, after adjusting for multiple covariates which may affect BMD. Intervertebral disc height was also investigated in view of its possible relation to fracture risk.

METHODS

A cross-sectional study of 100 patients with T2DM of at least 5 years duration and 86 non-diabetic subjects was carried out.

RESULTS

There were no significant differences in T scores in either the spine or femoral neck after adjustment for potential confounding variables between T2D subjects and controls. Diabetic patients had a statistically lower intervertebral disc height between the 2nd and 3rd lumbar vertebrae (D3) after adjustment for potential confounders (p=0.004). Urinary albumin:creatinine ratio, total cholesterol, LDL-cholesterol and cigarette smoking were independently associated with lower height of D3 in diabetic subjects.

CONCLUSIONS

There is no significant independent association between T2D and BMD. However we found a novel association of significantly lower disc height in patients with T2D. This may contribute to the increased vertebral fracture risk in subjects with T2D. Further studies are needed to investigate the relationship of disc height, T2D and fracture risk.

The Effect of Polymorphisms in SPP1 on Risk of Fracture: A Case-Control Study

Background

The purpose of the study was to investigate the correlation between rs4754 and rs6840362 polymorphisms of secreted phosphoprotein 1 (SPP1) gene and fracture risk.

Material/Methods

rs4754 and rs6840362 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 130 patients with fracture and 107 healthy controls matched with the former by age and sex. Hardy-Weinberg equilibrium (HWE) was assessed in the control group based on the genotype distributions of SSP1 poylmorphisms. The differences in genotype, allele, and haplotype frequencies between cases and controls were detected by the chi-square test, and the relative risk of fracture is expressed by odds ratio (OR) and 95% confidence interval (CI). The linkage disequilibrium (LD) and haplotype analyses were conducted with HaploView software.

Results

The TT genotype in rs4754 had significant difference in patients with fracture and controls (10.77% and 4.59%, P=0.04) and the results showed that people carrying TT genotype of rs4754 were more susceptible to fractures than CC genotype carriers (OR=3.00, 95%CI=1.02–8.89). The T allele also had 1.54 times higher risk of fractures (OR=1.54, 95%CI=1.04–2.30), but this was not true for the rs6840362 polymorphism. LD between the 2 polymorphisms and haplotype C-T (rs6840362-rs4754) increased the susceptibility to fracture (OR=2.01, 95%CI=1.23–3.28).

Conclusions

SPP1 rs4754 polymorphism may be related to risk of fracture, but not rs6840362.

Diabetes and bone: biological and environmental factors

PURPOSE OF REVIEW

Type 1 and type 2 diabetes mellitus are known to increase fracture risk. It is known that type 1 diabetes mellitus is associated with lower bone mineral density, but for type 2 diabetes mellitus, the real risk of increasing osteoporotic fractures is not explained by bone mineral density, which was found to be normal or paradoxically higher than controls in several studies, thus claiming for further investigations. This review summarizes some of the newest findings about factors that contribute to bone alterations in diabetic patients.

RECENT FINDINGS

Most recent evidences showed that bone of diabetic patients presents a cortical porosity which is not captured by the bidimensional densitometric measurements as performed by dual energy X-ray absorptiometry. Other studies investigated bone matrix searching for molecular mechanisms underlying the reduced bone strength in diabetic patients. The loss of bone biomechanical properties in diabetes has been associated to the glycated collagen matrix induced by hyperglycemia. Other studies analyzed the effect on bone microarchitecture of the most common antidiabetic drugs.

SUMMARY

Disease management of fracture risk in diabetic patients needs new methodologies of assessment that also take into account bone quality and evaluation of clinical risk factors, including balance, visual, and neurological impairments.